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Rice straw is an important renewable resource. Under the circumstance of global resource shortage and energy shortage, it is of great significance to vigorously develop comprehensive utilization of straw. It is not only an important way to realize agricultural circular economy and low-carbon economy, but also involves sustainable development issues such as soil fertility, environmental security and efficient utilization of renewable resources in the entire agricultural ecosystem. Straw fiber ecological blanket has a good function of air permeability and water permeability, and has a significant positive effect on the ecological protection of soil surface microenvironment. Mechanical kneading is the key technology for the dismantling and optimization of agricultural waste straw fiber. In this study, the optimal process input is the spindle speed, hammer tooth clearance and material water content, and the output is the straw silk rate and calibrated unit productivity. An intelligent model was developed using Box-Behnken response surface method (RSM) to determine the functional relationship between input and output parameters. The three evaluation index models all have high reliability, and the determination coefficients are R 2 > 0.95 and R 2 > 0.94, respectively. The variance analysis of RSM regression model clarified that the influence of various factors on straw silk ratio was in the order of spindle speed > water content > hammer tooth clearance, and the linear relationship between spindle speed and straw silk ratio was increasing. The significant influence on the calibrated unit power productivity of the kneading machine is in the order of hammer tooth clearance > spindle speed > moisture content. When the hammer tooth clearance is constant, it decreases first and then increases with the spindle speed and straw moisture content. The results of factor interaction analysis showed that when the water content of straw was 40%, the spindle speed was 2 500 r/min, and the hammer tooth clearance was 13 mm, the silk ratio of rice straw was 96.75%. When the straw moisture content is 60%, the spindle speed is 2 300 r/min, and the hammer tooth clearance is 11.08 mm, the maximum calibrated unit power productivity is 29.96 kg/(kW·h). Mathematical model process parameters optimization: straw moisture content is 41.2%, spindle speed is 2 498 r/min, hammer tooth clearance is 12.84 mm. Under the combination of these parameters, the rice straw silk ratio is 96.93%, and the calibrated unit power productivity is 29.33 kg/(kW·h). Under optimized conditions, the proportion of fibers with length of 40～70 mm and > 70 mm showed an increasing trend, especially the fiber with length of > 70 mm increased by 120.55%. The proportion of fiber length-to-width ratio > 50～80 and > 80 increased from 17.39% and 6.52% to 38.64% and 16.01%, respectively. Ultra depth of field microscopy showed that the self-interweaving formability of kneaded straw fiber was significantly improved. The optimized mechanical kneading cost of straw fiber can be reduced by 27.50 yuan/t. The mechanical kneading technology strategy of the RSM model developed in this paper is effective for improving the decomposition rate of biomass straw and reducing the consumption of biomass straw, and can be widely used in the production of high-value agricultural products based on large fiber bundles of straw. The mechanical kneading technique strategy of the RSM model developed in this paper is effective for improving the decomposing silk rate and reducing the consumption of biomass straw, and can be widely used in the production of large-size fiber bundle straw based high-value agricultural products. [ABSTRACT FROM AUTHOR]

Sericulture has a pivotal position in the agricultural production of China. The number of silkworms is one of the key indicators in the process of silkworm breeding, which is crucial to the feeding and healthy growth of silkworms. Accurate detection of the number of silkworms can ensure the quality of sericulture products. However, manual counting has not fully met the needs of large-scale production in recent years. There is a high demand to combine AI technology for silkworm counting. In this study, silkworm detection and counting were studied from the perspective of deep learning. Several challenges were solved in the detection of silkworms. Since the silkworms belonged to the small targets, it was difficult to detect the fewer features; When the number of silkworms was high, serious masking occurred to cause interference in the detection of densely distributed silkworms; It was difficult to ensure that the clear images of silkworms were captured from the actual production. The blur images were easy to deteriorate the accuracy of detection. Two tasks were covered as follows. 1) The image dataset of silkworms was constructed; 2) MAM-YOLO, a silkworm detection and counting model was proposed using multi-dimensional perception. The pictures of silkworms were first taken from the Guangxi Sericulture Technology Promotion Station. These pictures of silkworms were preliminarily processed. The polygon annotation was then selected, according to the body and distribution of silkworms. The pictures of silkworms were annotated with the open-source tool (Labelme). Finally, the dataset was expanded using image transformation and noise addition. The silkworm picture dataset was obtained for the subsequent training, verification, and testing. An improved YOLOv8 (MAM-YOLO) was proposed to detect the silkworm, in order to realize the accurate detection and counting. A silkworm detection and counting model was proposed using space-to-depth transformation and image deblurring. The fine-grained detection performance of blurred images was improved in the MAMYOLO model. The space-to-depth transformed convolution was utilized instead of stride convolution for the pooling layer in the feature extraction. The fine-grained features were extracted from the images, in order to further improve the detection of the low-resolution and small targets. In addition, the impact of blurred images on the detection performance was reduced by introducing a deblurring module into the model. RCS-OSA module was added to the YOLOv8 model. The network feature extraction was improved to integrate the information of different sizes in the receptive fields. The detection head of the original network was improved into the multi-dimensional sensing head. The three-dimensional features of size, space, and channel were aggregated to enhance the detection of silkworm targets. The loss function was replaced with the EIOU loss function. The regression accuracy of the detection frame was improved to reduce the object occlusion. Experimental results show that the MAM-YOLO more accurately detected the silkworm targets. The detection speed of mAP@0.5:0.95 reached 74.8% and 22.2 frames per second, indicating the better functions of silkworm detection and counting with high precision and high rate. The detection requirements were fully met in the actual work of the Guangxi sericulture station. The results show that the silkworm detection and counting system of the technical indicators met the application requirements. The finding can provide the detection services for the actual production work of the silkworm breeding station. In the end, a generalization experiment was conducted on the Global Wheat Challenge 2021 dataset. It was found that the MAM-YOLO was also achieved in the better detection performance of wheat ears, particularly on the small targets similar to dense occlusion.Sericulture has a pivotal position in China's agricultural production. The number of silkworms is a key indicator in the process of silkworm breeding, which is crucial to the feeding and healthy growth of silkworms, and accurate detection of the number of silkworms can ensure the quality of sericulture products. The traditional way of counting silkworms manually is inefficient, and it needs to be combined with technology to intelligently complete this kind of heavy work. In this thesis, from the perspective of deep learning, a silkworm detection and counting method is studied, and several problems in silkworm detection are solved: silkworms belong to small targets, which have fewer features so that they are not easy to detect; silkworms are densely distributed, and when the number of silkworms is high, serious masking phenomenon occurs which causes interference in the detection; it is difficult to ensure that the images of silkworms obtained in the actual production are clear, and blur images will make the detection affected. The main research content of this thesis is as follows: This chapter completed two main tasks: 1) Completed the production of silkworm image data set; 2) MAM-YOLO, a silkworm detection and counting model based on multi-dimensional perception, was proposed.In this paper, pictures of silkworms were taken by workers from Guangxi Sericulture Technology Promotion Station. First, these pictures of silkworms were preliminically processed. Then, according to the characteristics of the body and distribution of silkworms, the polygon annotation method was selected, and the pictures of silkworms were annotated with the open-source tool Labelme. Finally, the data set is expanded by means of image transformation and noise addition, and finally the silkworm picture data set is obtained for subsequent training, verification and testing.This chapter proposes an improved silkworm detection method based on YOLOv8, MAM-YOLO, which realizes accurate detection and counting of silkworm. Secondly, aiming at the problems of loss of fine-grained information and poor detection performance of blurred images in the MAM-YOLO model, a silkworm detection and counting model based on spaceto-depth transformation and image deblurring is proposed. The model utilizes space-to-depth transformed convolution instead of stride convolution and pooling layer in the feature extraction process, so that fine-grained features in the image can be extracted, which further improves the detection capability for low-resolution and small targets. In addition, the impact of blurred images on the detection performance is reduced by introducing a deblurring module into the model. By adding RCSOSA module to YOLOv8 model, the capability of network feature extraction is improved, and the information of different size receptive fields is integrated. The detection head of the original network is improved into multi-dimensional sensing head, and the three-dimensional characteristics of size, space and channel are aggregated to enhance the detection ability of silkworm targets. By replacing the loss function with EIOU loss function, the regression accuracy of detection frame is improved and the problem caused by object occlusion is reduced. Experiments show that MAM-YOLO can more accurately detect silkworm targets, and the detection speed of mAP@0.5:0.95 reaches 74.8% and 22.2 frames per second, which realizes the functions of silkworm detection and counting with high precision and high rate, and can meet the detection requirements in the actual work of Guangxi sericulture station. results show that the silkworm detection and counting system of the technical indicators have met the application requirements, and can provide detection services for the actual production work of silkworm breeding station.In the end, a generalization experiment was conducted on the Global Wheat Challenge 2021 data set, and it was found that MAM-YOLO also showed a high improvement in the detection performance of wheat ears, proving that the proposed method can generalize to other small targets similar to dense occlusion. [ABSTRACT FROM AUTHOR]

With the active promotion of the concept of common prosperity, farmland has once again become the focus of attention in political and academic circles, and many scholars have advocated the further visualization of the property value of farmland elements to increase farmers' income. To promote the coordinated development of China's food security and common prosperity strategies, this paper attempts to reveal the dilemma facing farmland capitalization. Theoretically, based on the factor allocation decision logic of full-time and part-time farmers, this paper proposed the dilemma of farmland capitalization between increasing food production and farm household income. We empirically constructed a model to measure farmland capitalization and characterized its degree in 27 provinces in China's mainland from 2004 to 2020. The study also provided empirical support for the theoretical analysis by using a threshold regression model and a mediating effect model based on 790 microsamples from typical provinces. The results found that: ① Farmland capitalization showed a trend of increasing year by year nationwide, with a spatial distribution pattern of spreading from the center to the surrounding areas, and the provinces with a higher degree of farmland capitalization were concentrated in the main grain-producing areas. ② The impact of farmland transfer prices on grain production had structural effects depending on the degree of farmland capitalization: In the moderate capitalization scenario (farmland capitalization≤1.011), farmland price increases promoted the expansion of food crop acreage; in the excessive capitalization scenario (farmland capitalization≥1.154), farmland price increases suppressed food crop acreage. ③ Farmland capitalization helped to meet farmers' psychological expectations on the value of farmland assets, and significantly increased farmers' income by promoting two paths: the outflow of farmland and off-farm employment. ④ Farmland capitalization in China was facing a dilemma between increasing food production and increasing farmers' income, which posed an important potential problem for national food security. The capitalization of farmland can not only improve the problem of insufficient property income in the income structure of farm households, but also promote the non-farm transfer of rural labor, but behind it is the fact that a large amount of farmland is 'nongrain.' In the future, the Chinese government should emphasize the production factor attributes of farmland, use policy tools to guide the rational return of farmland prices, improve the market for productive agricultural services, and prevent the risk of farmland over-capitalization. [ABSTRACT FROM AUTHOR]

Conservation tillage is an important way to ensure the sustainable utilization of cultivated land and a key measure to speed up the implementation of a food crop production strategy based on farmland management and technological application. Its economic effects have attracted more and more attention from all walks of life. Based on the micro-survey data from 2 127 grain growers in the main grain-producing areas, this paper applied the stochastic frontier production model to estimate the grain production efficiency of adopters and non-adopters. The Tobit model and propensity score matching method were implemented to examine the impact of the adoption of conservation tillage technology on grain production and environmental efficiency. The main results showed that: (J) The adoption of conservation tillage technology had the effect of ' increasing efficiency and reducing emissions' in grain production, and the conclusion was still valid after alleviating possible endogenous problems and a series of robustness tests. © In terms of scale, small-scale farmers adopted conservation tillage technology 'only to increase efficiency, not to reduce emissions,' medium-scale farmers adopted the technology ' only to reduce emissions, not to increase efficiency,' and large-scale farmers adopted the technology ' to increase efficiency and reduce emissions.' © In terms of production efficiency, the adoption of conservation tillage technology by farmers with high production efficiency ' not only increased efficiency but also reduced emissions.' The effects of ' increasing efficiency' and ' reducing emissions' adopted by farmers with medium or lower production efficiency were not verified. ® In terms of technology combination, adopting conservation tillage technology in combination focused on improving efficiency. The adoption of the combination of ' straw returning to field+subsoiling,' ' straw returning to field+no-tillage direct seeding,' and ' subsoiling+no-tillage direct seeding+straw returning to field ' significantly improved grain production efficiency but did not play its due positive role in environmental efficiency compared to non-adopters. Based on the conclusion of the empirical research, we should attach great importance to the popular application of conservation tillage technology and guide and support farmers to actively and consciously adopt this technology. On the other hand, it is necessary to combine the resource endowment and actual production demand of different types of farmers and selectively formulate the popularization scheme of conservation tillage technology. [ABSTRACT FROM AUTHOR]

During the War of Resistance Against Japanese Aggression, Guangxi, an important region for agricultural production of the national government and the new Gui Clique, formulated the Outline of the Implementation Plan for Grain Production Increase from 1938 to 1943 in order to expand grain production, ensure army provision supply and sustain people's livelihood. Through analysis of the outline, this paper discussed diffusion environment, spatial variation and technical measures taken to boost grain yield. During the implementation of the plan, Guangxi was damaged to some extent by two invasions of the Japanese army, and this paper made rather objective evaluation of the implementation and effects of the Outline of the Implementation Plan for Grain Production Increase. [ABSTRACT FROM AUTHOR]

Ethoxyquin (EQ) is one of the antioxidants widely used in the global feed industry. Due to its advantages of wide application, good function and low cost, EQ have been intensively used in agricultural production for a long time. In 2017, the European Union issued a moratorium on the use of EQ in the feed industry, making its safety become the focus of attention. The issue of EQ safety was once again brought into focus by the publication of regulations in 2022 concerning the non-approval of EQ as feed additive belonging to the functional group of antioxidants. In order to fully understand the application and safety of EQ in feed industry, the production process optimization, the application history of EQ used in feed industry, product quality and performance research, application and safety evaluation of EQ, and possible risks and problems of EQ in the application of feed industry were reviewed in this paper. This review provides reference for the scientific application and safety evaluation system construction of antioxidants in China feed industry. [ABSTRACT FROM AUTHOR]

The digital economy is gradually becoming a powerful engine for high-quality economic development in China and plays an important role in the construction of digital villages and the integrated development of rural industries. Starting from the mechanism of reducing transaction costs in the digital economy, it is a feasible perspective to analyze the role of the digital economy in promoting the integration and development of rural industries in China. This paper evaluates the impact of the digital economy on the development of rural industries in China, analyzes the current situation and problems in the construction of digital villages in China, and uses transaction cost theory to analyze the role of digital technology applications in reducing transaction costs in agricultural production, sales, and financial services. It finds out various rural industrial integration modes formed in the process of digital rural construction, and proposes policy suggestions to promote the integrated development of digital economy and rural industries in China. [ABSTRACT FROM AUTHOR]

Accurate monitoring of crop spatial distribution in topographically complex areas is of great significance for guiding agricultural management production and reasonable allocation of resources. However, scattered crop distribution and high spatial heterogeneity pose challenges for precise classification. The objective of this study was to explore a method for simultaneous precise identification of multiple crops with multi-temporal high-resolution satellite data under complex terrain conditions, thus further providing a theoretical and practical basis for crop identification in Chongqing city area and the complex low hills area in southwest China. The western Chongqing was selected as the study area. First, a multi-scale segmentation algorithm was adopted to construct homogeneous units from fields of the same feature type. This approach helped to achieve high accuracy classification by avoiding overly fragmented classification results based on pixel classification. Secondly, the multi-temporal Sentinel-2/MSI remote sensing images were used to explore the weathering patterns and characteristic parameters during the fertility period of major food crops. The spectral indices, such as NDVI, RVI and NDWI, were constructed to compare the differences in remote sensing spectral information of different crop types at various fertility periods based on ground sample points. Such information was then combined with the topographic features to determine the optimal combination for crop identification. Finally, an object-oriented decision tree logical classification rule set was established to extract major grain crop growing areas. The results showed that, (1) the multi-scale segmentation method was an effective approach that can make crop identification on a field basis. In addition, the vegetation edge segmentation was optimal at a segmentation scale of 30 and a compactness and shape factor of 0.5. (2) The target feature discrimination threshold was established by combining the spectral feature indices of NDWI in April, RVI in June, NDVI in August and NDVI in August with the topographic features such as altitude and slope. The overall accuracy of the classification reached 90.8%, being 85.7%, 83.3% and 80.7%, for paddy rice, maize, and sweet potato, respectively. This paper showed that the crop planting area identification method based on multiple spectral indices combined with topographic features can achieve high recognition accuracy and has practical significance. [ABSTRACT FROM AUTHOR]

The synthesis methods of isothiazolinone compounds, the modification methods of each site and the application progress in the fields of industry, agriculture and medicine are reviewed. The kind of compound has a wide range of biological activities, such as high efficiency, low toxicity and broad spectrum. It is mainly used in sterilization, algae killing, anticorrosion, antifouling and so on. It is a hot spot in the field of chemical research in recent years. At present, there are commercial products such as Kathon and Sea- Nine 211 (DCOIT). Isothiazolinone compounds play an important role in industrial and agricultural production and life. The application and research progress of isothiazolinone and its derivatives in medicine, pesticide, coating, textile, papermaking, leather making and other fields in recent years were discussed. Finally, the development direction and application prospect of isothiazolinone compounds were prospected. [ABSTRACT FROM AUTHOR]

Dunhuang is not only one of the important agricultural regions in China, but also has formed a unique food custom through the integration of diverse cultures along the Silk Road, becoming a grain production base in the Western Regions. Ancient Dunhuang people explored the path of agricultural development in the long-term production practices, actively promoting agricultural production in the region, and transforming the agricultural production structure, leading to a shift in the mode of production. This paper aims to correctly understand the agricultural production characteristics and patterns of ancient Dunhuang and explore the impact of Dunhuang’s agricultural development on local culinary customs, providing an insight into the overall picture of ancient Dunhuang’s agricultural production and lifestyle. [ABSTRACT FROM AUTHOR]

Carbon emission from crop production is one of the important sources of greenhouse gas emission in China, and it is a hot issue on agricultural ecological environment in recent years. Based on the statistical data of agricultural production input, crop yield, cultivated land area and crop sowing area in Hebei province from 2010 to 2018, this paper studied the dynamic changes of carbon emission of crop production inputs, and analyzed the proportion of carbon emission for each different crop production inputs, so as to provide a theoretical basis for energy conservation and emission reduction in agricultural production, and in the end to realize the low-carbon agriculture. The results showed that from 2010 to 2018, the carbon emission from crop production in Hebei province took 2015 as the turning point, showing a trend of increasing first and then decreasing. From 2010 to 2018, the total carbon emissions from crop production, carbon emissions per unit yield and carbon emissions per unit cultivated land area in Hebei province were 22.19-104-26.74x104tCO2 eq, 0.21-0.30tCO2eq·t-1 and 3.40-4.10tCO2eq·ha-1, respectively. The total carbon emission of crop production, carbon emission per unit yield and carbon emission per unit cultivated land area in 2018 were the lowest, decreasing by 17.0%, 30.0% and 17.0% respectively compared with the highest value. The 9-year average carbon emission of chemical fertilizer, pesticide, agricultural film, diesel fuel and irrigation electricity accounted for 38.6%, 2.1%, 11.5%, 34.7% and 13.1%, respectively. Chemical fertilizer and diesel fuel were the main sources of agricultural carbon emission, accounting for more than 30%. The dynamic change of carbon emission of crop production inputs was obviously affected by the national policies. It is suggested that the carbon emissions from agricultural production should be guided by national policies, and measures such as formulating mature agricultural management system, strengthening agricultural technology training and promoting the application of advanced cultivation techniques should be taken to reduce the carbon emissions from agricultural sources, so as to promote the green development of agriculture. [ABSTRACT FROM AUTHOR]

Agricultural carbon productivity has the dual attributes of 'guaranteeing growth' and 'promoting emission reduction.' It is the core content of green agriculture development in the new era, and also an important aspect of achieving China' s goals of reaching peak carbon emissions and carbon neutrality. Based on new geographic economics, this paper established a spatial panel model and used panel data from 31 provinces (excluding Taiwan, Hong Kong, and Macao) and municipalities in China from 2005 to 2019 to empiri⁃ cally study the agglomeration effects of agricultural industries on agricultural carbon productivity and investigated the moderating effect of fiscal decentralization on the above effects. The main findings were as follows: ① The agricultural carbon productivity of China as a whole and that of the four major regions were increasing year by year, and there was a certain spatial correlation. ② When the control variables were not considered, the agglomeration of agricultural industries had a significant U-shaped effect on the carbon productivity of local agriculture, but it was not conducive to the agricultural carbon productivity of surrounding areas. When the control variables were considered, the agglomeration of agricultural industries had no significant effect on the carbon productivity of local agriculture. However, it had a significant inverted U-shaped effect on agricultural carbon productivity in surrounding areas. ③ The effects of agricul⁃ tural industry agglomeration on agricultural carbon productivity were significant in the four major regions, regions of different agricultur⁃ al development levels, and regions with different agricultural industry agglomeration levels, and heterogeneity existed in these places. ④ Fiscal decentralization would weaken the impact of agricultural industrial agglomeration on agricultural carbon productivity at the national level and would have a heterogeneous moderating effect in low agricultural industrial agglomeration regions (eastern and cen⁃ tral regions) and high agricultural industrial agglomeration regions (western and northeastern regions). Therefore, it is necessary to pro⁃ mote the transformation of agricultural industrial agglomeration from 'quantity increase' to 'quality improvement,' and to give full play to the role of agricultural industrial agglomeration in promoting agricultural carbon productivity. At the same time, we should: establish a dynamic adjustment mechanism for central and local fiscal revenues and expenditures; appropriately increase the proportion of fiscal support to agriculture; use financial resources and means to promote the rational agglomeration of the agricultural industry; and improve agricultural carbon productivity to achieve high-quality agricultural development. [ABSTRACT FROM AUTHOR]

Whether farmland transfer can produce farmers’ income growth is an issue that has been widely concerned by society. However, previous empirical studies are quite different. This paper believes that the neglect of the heterogeneity of the impact of farmland transfer has led to these different conclusions. Thus, using the China Family Panel Survey (CFPS) data during 2010-2018, this paper analyzed the impact of farmland transfer on different types of farmers and different sources of income. The basic empirical results showed that: Firstly, farmland transfer did increase the income of farmers, but it was mainly on transfer‑out farmers, and the impact on the net income of transfer ‑in farmers was not obvious. Secondly, the impact of farmland transfer on different sources of income of the transfer‑in farmers and transfer‑out farmers was inconsistent. The growth rate of wage income of transfer‑out households was much higher than the decline rate in operating income. And wage income contributed 80% of the growth in net income of transfer‑out households; as for transfer ‑in households, the growth in operating income could not compensate for the decline in wage income, which eventually could not increase their total income obviously. The above empirical results did not change after a series of model sensitivity analyses such as the difference‑in‑differences model and the treatment effect model, indicating that the basic conclusions were robust. Furthermore, we analyzed the reasons for income heterogeneity and found that the key mechanism was on the labor resource allocation decision. Actually, for transfer‑out households, farmland transfer could increase the probability of migrant work and business opportunities, as well as the labor input for non‑agricultural production. On the other hand, for transfer‑in households, they would invest more labor in agricultural production and increase agricultural inputs. Further policy discussions also found that due to the weak dependence of transfer‑out farmers on technological improvement, the transfer‑out farmers only needed to ensure that they could find alternative jobs to obtain a higher income; but for the transfer ‑in farmers, due to lack of sufficient technical assistance, their land production improvement was limited. Thus, it was difficult to produce the optimization of resource allocation mentioned in the theory of land retention, which might limit the further expansion of the farmland transfer market. In summary, the research in this paper provides certain theoretical and empirical evidence for optimizing the land transfer policy, increasing the participation rate of land transfer, and finally realizing the improvement of the social welfare of farmers. [ABSTRACT FROM AUTHOR]

As one of the most important staple crops in China,wheat production target both high yield and high quality is very essential to simultaneously meeting the demands for food security and life quality. It has been found that both contents of key chemicals and processing quality vary greatly within different layers of wheat kernels. This provides a potential approach to achieve both high-yield and high-quality of wheat. In this paper,we detailly reviewed the spatial distributions of protein and its components,starch,dietary fiber and microelements. We further discussed the underlying mechanisms on the formation of protein and starch spatial distribution in the views of supply of substrate and synthetic capacity of protein and starch. The paper also summarized the regulation effects of cultivation practices on quality spatial distribution. Finally,we proposed the breakthrough solutions for exploring the underlying mechanisms on quality spatial distribution. This paper will provide research views for achieving the production of wheat with both high yield and high quality. [ABSTRACT FROM AUTHOR]

Gibberellic acid (GA) is a widely-used hormone that governs plant growth. At present, GA used in agricultural production is mainly from the liquid fermentation of the fungus Gibberella fujikuroi, but the yield is far from meeting the market demand. Metabonomics, as an important branch of system biology, has attracted extensive attention and made significant progress in the field of microbiology in recent years. This paper reviews the research progress at home and abroad in the fields of the type, production, application, and research process of GA, the concept, advantage, research technique, determination of GA on metabonomics, and the effect of genetic modification, abiotic stress, precursors on the biosynthesis of GA. The combined application of multiple omics related to the efficient synthesis of GA has also been prospected. It provides ideas for the further improvement of GA production in industrial production. [ABSTRACT FROM AUTHOR]

【Objective】The present paper aimed to deeply analyze the influence of the migration and transformation efficiency of available Se in the ‘soil-plant’ system under different forms and compositions, as well as the antagonistic or synergistic effect between Se-Cd.【Method】Through the investigation of crops and soils in the selenium-enriched soil area in Enshi prefecture, the bioavailability of Se in soil was studied by analyzing the correlation between potato Se-Cd content and available Se-Cd in soil. The coupling effect of Se-Cd was revealed from the perspective of effective state of Se and Cd.【Result】The key factor that determined the level of Se in the food chain was the available Se content in soil rather than the total Se content. The level of available Se content determined the level of Se content in potatoes, and Cd in the soil-potato system behaved a similar trend. The bioavailability of Se in soil was closely related to its existing form. The available Se in potato root soil was mainly organic Se and Se4+, and organic Se was most easily absorbed by potatoes. In terms of the Se-Cd coupling effect, as the molar ratio of available Se-Cd in soil increased, the Cd content in potato showed a downward trend, and the increase of available Se content in soil inhibited the potato’s absorption of Cd in soil. There was an antagonistic effect of Se-Cd, and was the strongest when the molar ratio of available Se-Cd in the soil reached 0.199.【Conclusion】The study can provide reference and theoretical basis for local selenium-enriched crops production, and provide evidence for improving the effectiveness of Se in soil, thus improve the added value of agricultural products and realize the efficient development and utilization of Se resources. The antagonistic effect of available Se in the soil on the formation of Cd absorption by plants should be included in the scope of soil environmental quality standard evaluation, so as to form a more scientific and comprehensive new system and new standard for soil environmental quality evaluation. [ABSTRACT FROM AUTHOR]

Different from traditional explanations arguing that population pressure led to the cultivation of maize, this paper believes that maize in the Qing dynasty planted by traditional slash and burn farming method of Xiangxi took the place of some conventional crops and became a new coarse cereal, which was caused by multiple factors such as national policy, market and eco-utilization. Emperor Yongzheng’s policy of the bureaucratization of native officers formed a unified market network and attracted external population to western Hunan, boosting tung oil industry and creating some areas of western Hunan with concentrated maize. Besides, emperor Jiaqing’s policy of agricultural collective production helped further expand the planting scale of tung trees and enabled the Miao-populated area to become the concentrated production region of maize. [ABSTRACT FROM AUTHOR]

It is needed to solve the problems such as relatively low input-output ratio and environmental pollution for Chinese agriculture, with the large amount of agricultural production and consumption. In the background of changing international situation and frequent natural disasters, transforming traditional agricultural production methods in China is an urgent. Driven by emerging technologies such as artificial intelligence, internet of things, cloud platform, automatic control, and new generation communication and so on, precision agriculture came out and was undoubtedly an effective way. Precision agriculture has become a common choice for developing sustainable and high-yield agriculture around the world. In order to obtain the development orientation of precision agriculture and successful practices in the world, this paper reviews the studies on precision agriculture developing status. The aim of this paper is to refine the experiences of precision agriculture developing in the main developed countries and regions and take a look at the precision agriculture development in China. Adopting the method of systematic literature analyzing and summary, Section 1 studies the development status of precision agriculture in the main developed countries and regions, such as America, Japan, European Union and Israel. The idea of precision agriculture was first proposed in America. Until today, America has developed mature precision agriculture system, which benefits from the highly developed technologies. Considering the serious contradiction between large population and less farmland, during 1970s, Japan took measures of consolidating farmland on a large scale and building farmland infrastructure and so on to improve the agricultural production conditions. The agricultural community was also formed to operate collaboratively the agricultural production. The development of precision agriculture in European Union is driving by digital technologies. The water-saving agriculture represented by drip-irrigation and sprinkler-irrigation has made remarkable results in Israel. The development experiences of precision agriculture in the main developed countries and regions enlighten us that: 1) the leading by government is the key; 2) the informatization construction is the foundation; 3) the advanced technology is the core; 4) the cultivation of new type of farmers is the guarantee. Section 2 analyzed the basements and weaknesses for developing precision agriculture in China. The weaknesses are the emphasis in this section. First, the farmland in China is scattered and the infrastructure is not perfect. Taking the informatization perspective, even though number of agriculture related information systems exist, the data and information are not interoperable between these systems. Second, at the present stage, we cannot acquire the temporal and spatial continuous agricultural information due to the rarity domestic satellite data and ground sensors for agriculture monitoring. Third, automatic variable operating system and equipment are lacking since the technology integration of information technology, communication and agricultural machine has not been achieved. Fourth, insufficient high-quality agricultural talents. Facing these weakness and Chinese conditions, Section 3 provided five suggestions to develop precision agriculture in China. Firstly, our government should overall plan and give guarantee in police making, infrastructure construction and financial support, etc. Secondly, we should improve the agricultural production condition through expanding moderately the operating scale of farmland and constructing the field infrastructure net and the national agricultural information platform. Thirdly, the key technology research, such as the information retrieval using remote sensing and technology integration of communication, automatic controlling, spatial information and smart machinery must be focused. Fourthly, the new type of personnel in agricultural field can be cultivated. Fifthly, pilot demonstration can be carried out according to the regional difference. [ABSTRACT FROM AUTHOR]

Pesticides play an active role in modern agricultural production. However, irrational application of pesticides may cause a negative impact on important pollinating bees. This paper mainly reviewed the research progress on the acute toxicity of pesticides to bees, the sub-lethal effects of pesticides on the growth, development, and behavior of bees, the combined effect of pesticides on bees, as well as the interaction between neonicotinoid insecticides and nicotinic acetylcholine receptors of bees, mechanisms of differential toxicity of pesticide to bees, effects of pesticides on detoxificationrelated enzyme activity and other physiological and biochemical indexes of bees, and the role of phytochemicals in regulating the tolerance of bees to pesticides. The main purpose of this review is to provide a reference for the rational use of pesticides and improve the safety of pesticides to bees. [ABSTRACT FROM AUTHOR]

As the final use form of pesticides, the quality and performance of pesticide formulations play a crucial role in the efficacy and efficient utilization of pesticides. In recent years, the innovation of pesticide formulations in China has been promoted with the improvement of people's awareness of environmental protection and the development of scientific and technological levels, and the constant changes in the types and occurrence regulation of harmful organisms, planting structure, plant protection strategy, land intensification and labor structure. Some new theories, formulations, processing technologies, characterization methods and application methods have emerged one after another, the refinement, functionalization and efficient utilization have become the main development directions of pesticide formulation. In this paper, we have made a comprehensive introduction to the development of pesticide formulation in our country from the aspects of refined development and functional development of pesticide formulation processing, and the promotion of pesticide formulation innovation by agricultural production needs. And we analyzed the problems to be solved and the future development direction, which provided a reference for the development of green and efficient functionalized pesticide formulations. [ABSTRACT FROM AUTHOR]

Soilless culture is the most advanced technology in modern agriculture, with nearly 180 years’ history. It breaks through the limitation that agricultural production depends on soil, and starts a new agricultural mode of offering an unlimited possibility in terms of time, space, yield and quality of agricultural production, which will play an important role in solving three key problems of human survival such as resourses, environments and foods. At present, soilless cultivation has been transferred from stage of experimental research to a stage of production and application, its key technology is becoming more and more mature, its production system is gradually improving, and its industrial scale is rapidly expanding. In this paper, the developmental status of soilless culture in the world was analyzed, and its technical progresses was introduced from three aspects such as nutrient solution, cultivation medium, cultivation system and its supporting equipment. Then we put forward some key research and development tasks, such as theoretical research, technical standards, supporting technologies, simplified technology integrating, nutrient solution recycling, and intelligent technology of soilless cultivation. The application prospect of soilless cultivation technology was analyzed from the aspects of green, environmental protection, water saving, high efficiency, high quality, modern agricultural production, and the development of urban and non-cultivated land agriculture. [ABSTRACT FROM AUTHOR]

Crop model remote sensing and play important roles in agricultural production monitoring, evaluation, and future prediction with their unique advantages. The integration technologies of crop model and remote sensing information have obvious application advantages and broad development prospects in monitoring, evaluation and prediction of large-scale and high-precision agricultural production. In order to promote the wider applications of these technologies in crop yield prediction, impact assessments of agrometeorological disaster, and agricultural decision-making to deal with climate change on a regional scale, the method of literature review were adopted in this paper. The development and application of crop models in Europe, United States, Australia and China were systematically summarized. The principle, characteristics and shortcomings of the current mainstream data integration methods were concluded. The practical applications of integration technologies of crop model and remote sensing information were summarized. The existing problems in improving the accuracy of data integration were discussed, and the future research direction was prospected. The results showed that the research and application of crop model and its integration with remote sensing data were extensive and intensive at home and abroad. The assimilation method could effectively improve the simulation accuracies of crop model, providing technical support for crop growth and yield evaluation on regional scales, impacts of climate change on yield, farmland management decision-making, etc. The uncertainties from crop model simulation results and remote sensing inversion data, diversities of data assimilation strategies, and scale effects were the limiting factors to further improve the accuracy and efficiency of integrated systems. Therefore, multi-source fusion of remote sensing data, multivariable cooperation in assimilation process, multi-type coupling of crop models, and high-performance parallel computing of data were the development trends of integrating crop models and remote sensing research in the future. [ABSTRACT FROM AUTHOR]

Soilless culture is the most advanced technology in modern agriculture, with nearly 180 years’ history. It breaks through the limitation that agricultural production depends on soil, and starts a new agricultural mode of offering an unlimited possibility in terms of time, space, yield and quality of agricultural production, which will play an important role in solving three key problems of human survival such as resourses, environments and foods. At present, soilless cultivation has been transferred from stage of experimental research to a stage of production and application, its key technology is becoming more and more mature, its production system is gradually improving, and its industrial scale is rapidly expanding. In this paper, the developmental status of soilless culture in the world was analyzed, and its technical progresses was introduced from three aspects such as nutrient solution, cultivation medium, cultivation system and its supporting equipment. Then we put forward some key research and development tasks, such as theoretical research, technical standards, supporting technologies, simplified technology integrating, nutrient solution recycling, and intelligent technology of soilless cultivation. The application prospect of soilless cultivation technology was analyzed from the aspects of green, environmental protection, water saving, high efficiency, high quality, modern agricultural production, and the development of urban and non-cultivated land agriculture. [ABSTRACT FROM AUTHOR]

The park-level agricultural energy internet has been constructed based on the characteristics of the modern agricultural industrial park. The key problems of park-level agricultural energy internet can be in three aspects: 1) Environment-energy-food synergy security. One of bottleneck problems can be industrial barriers between energy and agriculture. 2) The driving force of agricultural production. Inadequate investment in fixed assets and high energy costs are hindering large-scale agriculture. 3) Intensive and large-scale agricultural production. Cluster agriculture depends on the level of informatization and automation. In the development trends, the park-level agricultural energy internet will gradually realize the deep-level coupling and optimization of heterogeneous energy and agricultural production, while the synergy of agriculture and energy, to promote the development of clean energy but reduce environmental pollution. It is necessary to integrate new energy sources and modern agriculture, to enhance the large-scale operation of agricultural production using new industrial models. The integration of agricultural internet of things (IoTs) and the ubiquitous power IoTs, to shape the intelligent and clustered development of agricultural production. This paper analyzed the development status of park-level agricultural energy internet according to the key problems mentioned before. Then, three typical cases were introduced: One is the use of park-level biomass to achieve the co-production of gas, heat, electricity, and fertilizer; The second is a “complementary of fishery and photovoltaic” industrial model; The third is to achieve intelligent agricultural production through the agricultural Iots. This paper also proposes two key technologies and one operation mode: 1) Agriculture-energy coupling optimization technology. The physical system of park-level agricultural energy internet can be constructed in the way of deep coupling of energy and agriculture, to form the energy structure of “source-net-storage-load”. 2) The intelligent technology of agriculture. To form the interaction of ubiquitous power and agricultural Iots, and the information structure of the “perception layer-network layer-platform layer-application layer”. 3) Cross-border fusion mode of operation. There is a separation barrier in the mode of the traditional agriculture and energy operation, which can be break via the park-level agriculture energy internet with the cooperation management operation mode, to elevate the agriculture and energy domain trans-boundary fusion. Three features are information sharing, deep coupling, and complementation of production and consumption, with an emphasis on the coupling optimization of multi-energy heterogeneity and agricultural production behavior about industry barriers, meteorological disasters, industrial coupling, cutting-edge technology, and economic cost issues. Finally, the issue has been addressed on the implementation and practice of the framework for the park-level agricultural energy internet. [ABSTRACT FROM AUTHOR]

Rational construction of a well-facilitated farmland become necessary for food security and modern agriculture in China. In farmland construction, the automatic management of spatial data can benefit to accurately distinguish well-facilitated farmland from the various land types. Various discriminating ways of well-facilitated farmland are adopted due to the different influence factors of agricultural production in in different regions, where the spatial distribution and structural features of well-facilitated farmland are quite different from place to place across the country. Most of the previous studies focus mainly on policies, benefit evaluation, preliminary planning and design in the well-facilitated farmland construction. There is still lacking on the studies of the discrimination and analysis for the regional structural features of the well-facilitated farmland. In this paper, a framework of an index system was constructed to identify the spatial distribution and structural features of the well-facilitated farmland using the law of spatial differentiation together with the related national standards and strategic planning, ranging from the scale and shape of farmlands, irrigation and drainage facilities, traffic accessibility, and farmland protection ratio. The identifying system was designed on the basis of the index framework with C#. NET and Arc Object. Subsequently, the proposed system was verified for its availability by taking a case study of a Loess Plateau and a southern mountainous region. The results were as follows: (1) In the Loess Plateau area, the standard rate of the farmland scale, farmland shape, irrigation and drainage facilities, traffic accessibility was 87.01%, 83.12%, 80.52%, 90.91% and 83.12%, respectively. The well-facilitated farmland area can be identified by the system was 38.33 hm² with the total discriminating precision was 94.38%. There were some farmlands that did not meet the requirements of the well-facilitated farmland, such as incomplete irrigation and drainage facilities, the irregular shapes of the fields that distributed in the branch furrow and furrow head around the farmland. (2) In the southern mountainous area, the standard rate of all spatial features was 100%. The well-facilitated farmland area that identified by the system was 30.07 hm², which was 10.34 hm² higher than that of the state-approved well-facilitated farmland. The high identified areas can be because some fields that meet the requirements of well-facilitated farmland have not been classed as the permanent basic farmland in some administrative regions. When regardless of this classification, the total discrimination precision was 100%. This index system can be used in different scenarios, such as macro monitoring and evaluation, project design and inspection of the well-facilitated farmland. This system was also applied for the Northeast Plain, North China Plain, Loess Plateau and southern mountainous regions, while the key elements of the spatial features of well-facilitated farmland construction can be detected with a reliable discriminant resolution. When combining with the remote sensing technology, the index system can help automatic management to know the real-time spatial data of well-facilitated farmland construction. Therefore, the developed system can be successfully applied to identify the extract well-facilitated farmland in the construction area, and then to analyze the obtained spatial data in real time, finally to implement automatic management for well-facilitated farmland construction. Furthermore, the proposed system in this paper can offer a promising reference to the current comprehensive supervision platform, and improve the management effectiveness of well-facilitated farmland construction in modern agriculture. [ABSTRACT FROM AUTHOR]

Dividing farmland into different zones for facilitating management (management zone) at regional scales can help improve agricultural production in reforming agricultural technology implementation in China. Improving detailed prescription of the management zone division can provide guidance to farming and service optimization at regional scale.Appropriately selecting indexes in management zones can reduce the required data and can thus subsequently improve management.Available index selection usually relies on empirical knowledge of experts and /or multivariate statistical analysis. However, expert evaluation method could be bias, while the multivariate statistical analysis method cannot reduce the number of indexes compared to the original index set and thus need to supervise the data. In addition, most existing work on fragmentation of management zones focused on zone-dividing method rather than from index selection by removing indexes that lead to fragmentation. This paper aims to resolve these limitations with a proposed unsupervised filtering index selection method, based on the index correlation clustering (FSCC) using the concept of feature selection. FSCC reduces the original index set to obtain a subset called FSCC set. FSCC applies the correlation matrix of all indexes to cluster the original indexes set. It then selects all cluster centers as a representatives to form a new index subset as the FSCC set. The quantity of the indexes in the FSCC set was reduced,compared to the original index set, and the redundancy of the indices set was descended. To improve practical operability of the management zones, we applied the index optimization algorithm developed based on the consistency and integrity (CIO) to the FSCC set to remove indices which resulted in fragmentation. CIO couples Kappa Coefficient with fragmentation index to generate an optimization strategy for the FSCC sets. CIO screens the indices which lead to the fragmentation while, in the meantime, considering the consistency of the management zone results prior to and after the optimization. We applied the method to winter wheat in China, with factors that affect wheat growth, including meteorology, soil and topography, being divided at four regional scales. We first used the FSCC and the two traditional filter feature selection methods, Variance and Laplacian Score, to select index subsets for the four scales, and compared the resultant management zones produced from them. The CIO was then applied to the four scales produced by the FSCC. The results showed that the FSCC method preserves the diversity of the features in the original index set. It significantly removed the redundant indices and had a better performance in the management zones. The best performance shows that in Rugao 2.5 km Grain, FSCC less than 52.44%, 49.52%, 49.45% both of Variance and Laplacian Score in FPI, MPE, NCE. The CIO improved the management zones effect of the FSCC index set, which reduced the number of indexes and effectively removed the indexes that led to a number of isolated units or patches. Compare to FSCC, except Nantong 10km, CIO has an average decrease in FPI, MPE, NCE of 0.061, 0.078, 0.082. Usingthe four regional scales, FSCC and CIO presented in this paper were effective in selecting indices and have potential application in management zone division. [ABSTRACT FROM AUTHOR]

【Objective】The present paper aimed to explain the changes of hydrothermal resources in the growth period of foxtail millet and maize in Heilongjiang region, and to provide theoretical basis for crop safety production.【Method】Based on the daily weather data from 1957 to 2013 in Raoyang County and Penman-Monteith formula, precipitation anomaly percentage and growth length day（GDD）, this paper analyzed the changes of hydrothermal resources in Raoyang County from June to September.【Result】（i） The size of ET0 was June > July > August > September, and the climatic tendency rates were-5.85,-1.96,-2.59 and-1.46 mm 10 a-1, respectively. The decrease of ET0 in different months was affected by different ten days, June was mainly affected by mid-late days, July was affected by mid-late days, August and September were affected by early and mid-late days, respectively.（ii） The frequency of drought from June to September was 33.33 %, 19.30 %, 31.58 % and 38.6 % respectively. Light drought was dominant in June and July, light drought was dominant in August and moderate drought was dominant in September.（iii）From June to September, the growth degree days were 459.58, 516.49, 470.40 and 301.64 ℃·d, respectively. The climatic tendency rates were 1.19, 3.28, 0.46 and 3.10 ℃·10 a-1, respectively. The increase of growth duration in June and August was affected by the first and middle ten days, July by the first and second ten days, and September by all stages, with the greatest increase in the latter ten days. 【Conclusion】In the future interannual changes, for crops such as millet and maize growing in Heilonggang from June to September, the heat resources were abundant and increasing, but the drought risk will increase in July and August. Therefore, in agricultural production, we should improve the irrigation system in July and August, and strengthen the measures of water conservation and drought resistance in this stage. [ABSTRACT FROM AUTHOR]

In recent years, China's pig industry has gradually shifted to the northeast. Compared with the rich feed resources and land resources in Northeast China, the cold environment reduces the feed conversion efficiency and the production performance of pigs. In the winter of northern China, pig producers often face a huge problem of heat preservation when they control the environment of piggery. The aim of this study is to explore the heat preservation of piggeries in Northeast China. According to the investigation, there were four types of piggeries in Jilin Province, which were brick wall piggery, concrete wall piggery, color steel wall piggery and greenhouse piggery. The simulated piggeries with brick wall, concrete wall and color steel wall were based on the experimental piggery of Jilin Agricultural University, the simulated piggery with greenhouse was based on a piggery in a pig farm, and the simulated pig farm area was based on a pig farm area. Based on Ecotect software, this paper took a typical piggery in a large pig farm in Jilin Province as an object, and studied the light and heat environment of piggery, and the light environment of pig farm production area. The daylight factor of different heights in the piggery and the lighting situation in the production area of the pig farm were studied. The thermal insulation performances of 4 kinds of piggeries with different walls were analyzed. The results were as follows: The daylight factor of each research height of the experimental piggery was higher than 2%, which met the green building standard. The production area of the pig farm had good daylight, and the solar radiation in Great Cold Day could reach 5.38 MJ/(m²·d), and the sunshine was sufficient. The building spacing of the pig farm met the epidemic prevention standard, and there was no shelter problem. By comparing the monthly energy consumption values of 4 kinds of piggeries with different building materials, the best insulation performance of piggeries was as follow: Clay porous brick piggery, foam concrete pig piggery, color steel piggery with phenolic sandwich board, low density polyethylene film greenhouse piggery. After considering the cost, it was recommended to use cinder brick masonry piggery, fly ash aerated block piggery, polyphenylene sandwich board color steel piggery and low density polyethylene film greenhouse piggery. The daily energy consumption of empty piggery in December was tested and verified. The relative error range was 0.74%-8.62% after data comparison, which verified the reliability of the model. The simulation values of energy consumption were in good agreement with the measured values. On the one hand, it verified the correctness and rationality of setting parameters in the software. On the other hand, it showed that Ecotect software was feasible in piggery building. This paper can provide theoretical basis for exploring the light and heat environment of the northern piggery, and provide more ideas for architects to optimize the design before the implementation of the plan. [ABSTRACT FROM AUTHOR]

At present, when constructing basic farmland protection zone in China, they always pay more attention to the functional quality of basic farmland itself, while ignoring the relationship between basic farmland and supporting infrastructure and ecological land, and lack of awareness of “co-governing, co-construction, and management”. There is an increasingly intensified contradiction between the agricultural production and the development of construction land.The quantity,landscape and ecological systerm of basic farmland protection zone have been affected. In order to solve this main contradiction, this paper analyzes the theoretical framework system of the basic farmland protection community, and builds the basic farmland protection zone community vitality evaluation index system, taking Quzhou county, a typical agricultural county in the Huanghuaihai Plain, as the case zone.According to the research path of the basic farmland protection zone community “factor status analysis-community vitality assessment-damaged living body identification-comprehensive management and protection recommendations”, the community has conducted a more deep research in the three basic time points of 2009, 2013 and 2017. On this basis, the main conclusions of this paper are as follows:1）In view of the problems existing in the current basic farmland protection, on the basis of domestic and foreign research, the meaning of the basic farmland protectionzone community is defined as a community of life for mutual protection includes basic farmland, basic supporting facilities and small ecological space; 2）Based on the theory of life community, the indicators in the evaluation index system of the basic farmland protection community are divided into four aspects: survivability, development, stability and environmental pressure.Then the analytic hierarchy process is used to determine the level of the indicator system weights; 3）The basic farmland protection zone community is relatively stable and fluctuates between Level II and Level III. In 2009, the evaluation level of Quzhou county basic farmland protection zone community vitality was in the state of Grade III. Except Quzhou Town was in Grade II state, and the rest of the towns and villages were in Grade III state. In 2013, the evaluation of Quzhou county basic farmland protection zone community vitality is in the state of II, Quzhou town, Houcun town, Yanqiao township and Dahedao township are in grade II state, and the remaining townships are in Grade III state; in 2017, the evaluation of Quzhou county basic farmland protection zone community vitality is in Level III, except Quzhou town and Dahedao township are in the second-level state, and the rest of the townships are in the state of Grade III; 4)From the perspective of the spatial distribution of towns and villages, the trend of the level of vitality first rises and then declines during the inter-annual period. In 2013, the level of vitality evaluation was the highest in the township level II, and the distribution pattern of townships along the road network with higher vitality level was presented. The research results can provide a strong basis for strengthening the construction of the basic farmland life community knowledge system and comprehensive land improvement. [ABSTRACT FROM AUTHOR]

China′ s agriculture needs to feed 1.4 billion people and excessive fertilizer use has caused agricultural non-point source pollution. It is urgent to control agricultural non-point source pollution while ensuring food security. In this paper, we reviewed the development of agricultural productivity and productive relations in China since 1949. Smallholders face problems of the overuse of fertilizer, labor aging and hollow villages in China. Appropriate large-scale farming could alleviate these problems and lead to green development. Urbanization could promote large-scale farming in China and rebuilding the linkage between livestock and cropland is also needed. Where there is not suitable for large-scale farming, extension of industrial chain could revitalize agriculture via the integration of different industries. In the future, government and market should work together to guide rural-to-urban immigration to promote large-scale farming, encourage alternative farming models and finally promote agricultural modernization. [ABSTRACT FROM AUTHOR]

Global food security has aroused great concerns in developing areas. In most developing countries, triple burdens of hunger, under- nutrition (inadequate intake of macroand micronutrients), and over- nourishment (in the form of overweight and obesity malnutrition) coexist. There is a long way to achieve the dual goals of food security and nutrition security. By tracing 95 literatures, this paper aims to figure out the concept development and evolution of food security and nutrition security, and put forward the research priorities of future food and nutrition security. The article explores the evolution of the concept of food security and nutrition security and narrates the evolutionary characteristics, and finds that the concept of food security evolves from adequate supply of cereals to all foods, then to foods quality and nutritional security and sustainable development, with the dimensions of food security extending from a single availability dimension to multiple dimensions of availability, accessibility, utilization, stability, and sustainability. Subsequently, we review the research on food and nutrition demand analysis and forecasting, the capacity of food production, and import impacts; furthermore, we review the impact of income, market, urbanization and farmers' agricultural production on food consumption and nutrition security at the family and individual levels. To achieve the goal of the balanced development of nutrition for urban and rural residents, the paper provides an outlook for future food and nutrition research and brings out four important fields deeply touched to extend study scope and depth for food and nutrition security research in China. This review work reveals that it is of great significance to conduct research on agricultural production diversity, crop planting structure adjustment and crop nutrition enhancement, the impacts of urbanization and market development, and the vulnerable residents' welfare on the nutrition enhancement. [ABSTRACT FROM AUTHOR]

In view of the fact that the farmer faces the problem of difficult choice of agricultural joining mode, this paper investigates an agricultural products supply chain consisting of an agribusiness firm and a farmer for the production and supply of agricultural products by taking into account the uncertainty of market price and market demand. This paper also compares and analyzes the optimal decision-making behavior of farmers in the two agricultural joining modes of "protection price" and "land dividends". The study found that when the market size is large, farmers should choose "land dividends" mode; When the market size is small, the selection of farmers' agricultural joining mode is related to the uncertainty of market demand and the factors such as the contract price, the basic salary and the proportion of land dividend. [ABSTRACT FROM AUTHOR]

Water resources management in irrigation districts is important to ensure food security. The current water resources management in China focuses on underground water and surface water (i.e. blue water), and precipitation (green water). However, most studies are on large scale such as global or basin scales and few are on irrigation district scale. The aim of this paper was to quantify and evaluate the consumption of different types of water resources in the irrigation district by the concept of water footprint (WF). The maize and wheat production in the Baojixia Irrigation District of Shaanxi in China from 2008 to 2017 were selected as the case study. One hydrological station and two weather stations were included in the study area. Data of runoff, precipitation irrigation and soil-related physical properties were collected. A regional distributed hydrological model (Soil and Water Assessment Tool, SWAT) based on the hydrological cycle was established. The model was constructed by coupling with the soil water balance model and considering the water delivery losses of the irrigation canals. The blue and green water resources and WFs of crop production were quantified. The variability of the annual WFs of crops during the study period was analyzed, and the WFs of crops on daily and monthly scales were also analyzed in three typical years (dry, normal, wet). The runoff data was used to validate the SWAT model, and the MOD16A2GF Version 6 Evapotranspiration product (MOD 16) at a 500 m pixel resolution was used to verify the evapotranspiration simulation results. Then, the change of WF was analyzed. The results showed that the model could simulate well the runoff with the values of R 2 of 0.74, Nash Efficiency Coefficient (NSE) of 0.69 during the calibration period. By validation, the model was still well and both the values of R 2 and NSE were 0.51. It indicates that the model established in this study could accurately simulate the hydrological process in irrigation districts. During the period from 2008 to 2017, the blue and green water resources in Baojixia Irrigation District increased on the whole. The multi-year average blue water resources in Yangling was the highest but the multi-year average green water resources in Jingyang was the lowest. The multi-year average total WF values of maize and wheat (including the blue WF of irrigation delivery losses) were 573 and 779 m3 /t, respectively, showing an overall rising trend. The fluctuations of total WFs were mostly affected by the green WF. The green WF of crop production was higher at the jointing and filling stages and lower at the maturing stage. The WFs of crop production were fluctuated the most on the daily scale and the fluctuation decreased gradually from month scale to annual scale. The fluctuations of the green and blue WFs of wheat were the largest in the dry year. Although the irrigation water in the dry year was lower than the normal and wet years, the unit maize yield and the unit wheat yield were the highest and the total WF values of maize and wheat were the lowest. This study can provide valuable information for crop production and management in irrigation districts.. [ABSTRACT FROM AUTHOR]

Since 2004, with the rapid rise of labor prices, the application of agricultural machinery in China’s agricultural production has increased and the process of agricultural mechanization has been rapidly advancing in the “golden decade”. It is a research subject with both theoretical significance and policy reference value to explore the substitution of labor by agricultural machinery during this period, and to study the phased characteristics and continuity of factor substitution. Based on the provincial panel data from 2004 to 2016, this paper uses the translog cost function to calculate the substitution elasticity between machinery and labor in the production of 3 major grain crops i.e. wheat, maize and rice, focusing on the difference between crops and between regions, and their spatial and temporal variations. The data used in this paper come from National Agricultural Product Cost And Income Data Compilation, and China Statistical Yearbook (2002—2017). The results showed that: 1) The development of China’s agricultural mechanization experiences a “golden decade”, mainly due to the widespread, effective, and sustained replacement of labor by agricultural machinery, the substitution elasticity between agricultural machinery and labor for wheat, maize and rice was 0.581、1.324 and 1.153, respectively, and the mechanization of maize and rice at key production link is remarkable. 2) The substitution elasticity of wheat was stable at around 0.6 during 2004-2016, while the substitution elasticity of maize and rice showed a long-term downward trend, which decreased from 1.545 and 1.224 to 1.225 and 1.152 respectively. It means that when agricultural mechanization reached a higher level, the difficulty of factor substitution gradually increased and the substitution elasticity tended to decline, and it is much more difficult to increase the mechanization level of grain crops in the future. 3) Affected by factors such as the topography of operations, the development of agricultural mechanization in various provinces is at different stages, and there is a clear difference of the substitution elasticity between agricultural machinery and labor in grain production. The substitution elasticity of the southern low-lying hilly region, and the hilly and mountainous area in the southwest is generally higher than that in other regions, and there is a large space to increase the agricultural mechanization level in these regions, which might keep a remarkable increase. 4) With the general increase of mechanization level, the substitution elasticity shows the characteristics of temporal and spatial convergence, and the regional differences are gradually reduced and the whole tends to be stable. This can be used to explain the slowdown of the speed of China’s agricultural mechanization, and it also means that relying solely on the mechanization of food crops to stimulate the overall level of agriculture mechanization has become a thing of the past. In the future, the rapid growth of agricultural mechanization in China is faced with unprecedented difficulties and challenges, and it needs 5 aspects of measures to deal with this situation, such as enhancing the mechanization level of hilly and mountainous areas, promoting the mechanization toward whole and entire development, promoting the using of new multi-machinery and information-based smart machinery through machinery purchase subsidy policy, and reducing operational links and labor force participation directly. [ABSTRACT FROM AUTHOR]

As a consequence of population aging and shrinkage in China, the trend of labor shortage for agricultural production has grown and will continue in future. Acceleration of agricultural mechanization has been proposed as a developmental strategy in support of steady and sustainable development of agriculture in China. In alignment with this national developmental plan, the use of unmanned aerial vehicle (UAV) for pesticide application contributes to the advancement of plant protection mechanization by providing improved ability to apply pesticide in a time sensitive manner with enhanced safety and efficiency. The flight parameter of UAV was one kind of the most important indices affecting the quality of aerial pesticide application. To explore the distribution characteristics of pesticide spraying droplets deposition of UAV and the effect of flight parameters (flight altitude and velocity) and parameter accuracy on the deposition distribution characteristics, the spraying droplets depositions of 4 models of typical Chinese domestic UAVs (3WQF120-12, Mercury Ⅰ, 3WCJ8-10 and 3WQFTX-10) were tested in the wheat field in Xinxiang City, Henan Province in April, 2017. The high-precision Beidou navigation satellite system was used for recording the accurate working altitude, velocity and track of UAV, and the tartrazine tracer water solution of 0.5% was adopted to replace pesticide liquid for spraying. The filter paper with the diameter of 7 mm was used for collecting spraying droplets from UAV at the height of 0.7 m on the top of the wheat canopy, and the sensor of Zeno-3200 weather station was set at the height of 6 m to record the environmental parameters at test site. The size of the testing field was 50 m × 100 m and there were 15 sampling points in a straight line with 3 duplications for longitudinal droplet deposition distribution and 11 sampling points also with 3 duplications for crosswise one. During every test, the operator controlled the UAV remotely to take off, when the UAV reached the required height, then open the spraying system and make the unmanned aircraft fly over the experimental area according to the planned flight. After tests, the eluent from the filter paper was used to measure the absorbance of the tracer tartrazine by the 722 type spectrophotometer and the droplet deposition in every test was figured out. Combining the flight parameters with their coefficient of variation (CV) and root mean square error (RMSE), the impact factors on deposition distribution characteristics were studied and the results were analyzed by significance and regression analysis via SPSS 20 software. The results showed: The deposition in the area of both ends of flight route varied violently (30%＜CV＜70%) and there were the maximal values, while the deposition in the area of the middle of route was relatively steady (CV＜20%); the main factor impacting the crosswise deposition distribution was the overlap ratio of droplets of adjacent nozzles and spraying swath, and too high or too low overlap ratio both led to the poor uniformity of droplets distribution; with regard to pesticide application operation of single-rotor UAV, at the altitude of 1.1-1.2 m, and the velocity of 4.2-4.9 m/s, there was a high significant positive correlation between average droplets deposition and the RMSE of flight velocity (P＜0.01，r=0.952) and between the CV of the longitudinal droplets deposition and the CV of flight velocity (P＜0.01，r=0.963), and the CV of the total deposition was significantly negatively correlated with the average flight altitude (P＜0.01，r=-0.888). So, the method that the droplets deposition and distribution uniformity were analyzed and predicted by the flight parameters and their accuracy, such as the RMSE and CV of flight velocity and flight altitude, was reasonable, effective and feasible. The results of this study provide some theory reference for the determination of the ideal spraying parameters of UAV pesticide application work, the choice of environmental conditions of UAV operation and the formulation of standard working practice of UAV aerial spraying. [ABSTRACT FROM AUTHOR]

[Objective] Urbanization is currently one of the most significant features in China. In the progress of urbanization, some lands in the newly-built city that not developed currently are left for planting crops, while the change of land use poses new threat for farming, especially the soil heavy metal (SHM) pollution. In the present paper, taking Chenggong New District, Kunming as an example, we investigated the status of SHM pollution across 28 farmlands in Chenggong. [Method] The contents of soil Cu, Ni, Pb, and Zn were analyzed. Single factor pollution index (Cu, Ni, Pb, Zn), Nemerow integrated pollution index and Hankanson potential ecological risk index for each farmland were calculated. Spatial autocorrelation for each heavy metal was investigated based on Moran' s I. [Result] N emerow integrated pollution index ranged from 1. 39 - 3. 43, indicated the different extent of SHM pollution. The potential ecological risk index was small due to the low toxicological factors across the investigated heavy metals. The average Cu content was 2. 8 times for the background value and 1. 68 times for the national soil quality standard (II), besides, strong spatial autocorrelation and variation across the samples indicated the possible human influence. [Conclusion]These types of farmlands should be regulated and some heavy polluted lands should be prohibited for agricultural production to ensure the quality and safety of agricultural products. [ABSTRACT FROM AUTHOR]

[ Objective] The present paper aimed to reasonably use local agricultural climate resources and scientifically carry out maize planting. [ Method] According to climate data (1961 -2017) of 124 meteorological stations and long-term records (1981 - 2017) of maize phenology from 15 agricultural stations of Sichuan, the temporal and spatial distribution of light resources, temperature resources and precipitation during key maize phenological stages were analyzed in Sichuan Province. [Result] The total radiation during the whole growing period and different growth stages of maize both showed decreased trends. The higher radiation resources distributed to the southwestern of the basin and the southern of the Panxi agricultural area. The heat resources during maize growth period showed an increasing trend. Diurnal temperature range of Panxi agricultural area is obviously higher than the basin area. The reference evapotranspiration during each maize growth stages decreased. Water resources shortage occurred in most Panxi agricultural area and the old arid areas in the basin. [ Conclusion ] All regions should make rational use of light, temperature and water resources to provide scientific basis for relevant departments to formulate agricultural production measures and ensure the development of high yield and high quality of corn. [ABSTRACT FROM AUTHOR]

Rural territorial multifunction is essential to the sustainable development of a rural system. It is an important way to effectively identify the spatial pattern and obstacle functions in a rural territorial system, in order to optimize the allocation of rural elements and promote the rural revitalization. In theory, the effective identification of multifunction can provide scientific reference for the regional development orientation, spatial division, and mechanism innovation of rural revitalization. In practice, a useful guideline can be available for the functional orientation of rural areas, development plans, implementation of rural management policies and transformation. Taking Shandong Province as a research object, this paper aims to analyze the interaction between elements, structure and function in the rural regional system. According to the aspects of living, production, and ecology, six sub-functions were divided, including living and inhabitancy, life security, agricultural production, non-agricultural production, ecological conservation, and environmental maintenance. Firstly, a multifunction evaluation index system was established to calculate the indicator of rural territorial multifunction, together with the internal operation mechanism of structure and elements in the rural man-earth areal system. Secondly, an OpenGeoda software was selected to evaluate the multifunction global spatial autocorrelation of rural areas, and then an ArcGIS10.3 hotspot analysis tool was used to identify the local spatial autocorrelation. Finally, the control measures were proposed after a spatial partition type was constructed, where an obstacle function was used to clarify the obstacle diagnosis model, according to the multifunctional integration and coordination degree of rural areas. The results show: 1) The mean values of rural living function, production function and ecological function in Shandong Province were 0.429 8, 0.463 5, and 0.574 2, respectively. The comprehensiveness and coordination were between 0.28-0.76 and 0.51-0.99, indicating the spatial characteristics of “weak living function, medium production function and strong ecological function”; 2) The multifunctional Moran's I index in rural territorial system was all higher than 0.4 in Shandong Province. The spatial distribution features were positively correlated, particularly concentrated on the low functional values. Three regions, from the hot spot area to the cold spot area, the transition from Jiaodong Peninsula to central Shandong, and west Shandong, were in the form of spot patch, encircling strip block, segmented surface, and irregular mosaic surface, respectively; 3) According to the coupling relationship between comprehensive and coordination degrees, the rural territorial system was divided into five zones, including priority promotion area, key promotion area, potential promotion area, collaborative optimization area, and moderate optimization area. However, the obstacle function of each region has the double attribute of identity and difference. Specifically, the living function of population was the common obstacle of each region, whereas, the obstacle degree varied in non-agricultural production function and environmental maintenance function; 4) Some suggestions can be gained during this time. The regulation and control of rural territorial multifunction in Shandong Province can take “double high” as the goal, according to the policy of “finding the short board and developing together”, while strengthen the local key promotion and the optimization of rural functional areas based on local conditions, thereby to provide a promising potential to the rural high-quality development in the new era. [ABSTRACT FROM AUTHOR]

[Objective] The objective of the paper is to provide the scientific basis for rational fertilization in Jianhe County of Guizhou Province and similar areas. [Method] The effects of soil nutrient indexes(total N .organic matter, available N .available K, available P, total P and total K)on soil fertility are explored by using variation coefficient method, correlation coefficient method and weighted mean method, and then the soil fertility in paddy field and dry' land is evaluated by using improved Nemerow comprehensive evaluation method combined with the weight coefficient mean value of the three methods. [Result] The soil available k in paddy field and total P in dry land were at a lower level, while other nutrient indexes were at a medium-high, high and higher level. The soil available N content in six dry' land sampling sites with different plants was high. Soil total P and available k fluctuate greatly among sampling sites, while organic matter content fluctuates less. The soil available P in fertility factor weighted coefficient of paddy field and dry land was the highest, respectively 0. 2710 and 0. 2358 comparing the mean value of the three weighted method weighted coefficient. The available P is the main factor influencing soil fertility in paddy field and dry' land and soil fertility indexes is 1.52 and 1.63 separately. The soil comprehensive fertility was at a fertile level. [Conclusion] The soil fertility of paddy field and dry land in Jianhe County is at a fertile level, and available P is the main factor influencing soil fertility in paddy field and dry land. The soil N content in paddy field and dry land is high, which can meet the demand of crop production. Therefore, N fertilization should be reduced in production. The soil K content in paddy field is low, and the corresponding fertilization measures should be taken to improve K supply level in paddy field. [ABSTRACT FROM AUTHOR]

[Objective] The aim of this paper is to provide reference for local cultivated land quality protection, wheat safety production and agricultural planting structure adjustment. [Method] Wheat seeds and root soil samples were collected to investigate contents and occurrence forms of heavy metals in root soil and enrichment characteristics in wheat. [Result] The content of heavy metals in wheat seeds and root soil were lower than the safety values of food and soil referred in relative national standards. In root soil, most of As and Pb fractionated in residual fraction, while Hg concentrated in humic acrid bounded fraction, residual fraction and strong organic matter bounded fraction. Moreover, In soil the content of Pb in Fe-Mn oxides bounded fraction and residual fraction, Hg in humic acid bounded fraction and residual fraction, As in residual fraction and Cd in Fe-Mn oxides bounded fraction were positive with the total content of these corresponding elements. The content of Pb in exchangeable fration, Hg in strong organic matter bounded fraction and As in humic acid bounded fraction were passive with the pH value of soil, whereas the content of As in exchangeable fraction and Cd in carbonate bounded fraction were posetive with the pH value of soil. Additionally, the accumulation factors essential distinguished among each other in wheat seeds, where Zn was the most strong one. The content of Zn in wheat seeds was significantly restricted by the total content of Zn in soil, whilst Cd was obviously controled by both of the pH value of soil and the available content of Cd in soil, Hg and Cr were strongly limited by the content of organic matter in soil. [Conclusion] The content of heavy metals in wheat seeds and root soil in the studied area were lower than the safety values of food and soil. As and Pb were predominately appeared in residual fraction, while Hg fractionated in humic acid bounded fraction, residual fraction and strong organic bouded fraction in soil. However, the bioavailability and potential ecological hazards were greatest for Cd. Therefore, the pH value of soil, organic matter and the total content were regarded as the main factors controled the content of heavy metals in different fraction. The ability of wheat seeds accumulated heavy metals from soil were significant different. The biggest accumulation factor was observed for Zn which was intensely influenced by the total content in soil. [ABSTRACT FROM AUTHOR]

Fertilizer is an important condition for the crops growth and yield. In recent years, the use of agricultural fertilizer in China has increased significantly, which has brought a lot of environmental pollution and resource waste. Therefore, rational fertilization is one of the urgent problems in agricultural production. In order to solve the problems of unreasonable fertilizer distribution and low efficiency in banana fertilization operations by hands, this paper designed a variable rate fertilizer applicator based on the distribution characteristics of the banana roots. The distribution characteristics of banana roots at different growth stages were analyzed statistically, and the theory of variable rate fertilization was constructed. The fertilization decisions based on the distribution characteristics of banana roots were obtained, and the variable rate fertilizer applicator was designed, the prototype experiments were carried out. The results showed that the length of fertilization at the banana seedling stage was not more than 22 cm, the amount of total fertilization was not more than 0.150 kg, the ratio of fertilizer amount sowed in the primary and secondary fertilization areas was about 5:8:5 and the fertilization length ratio was about 1:2:1. The fertilization length at the vegetative growth stage was not more that 42 cm, the amount of total fertilization was not more that 0.200 kg, the ratio of fertilizer amount sowed in the primary and secondary fertilization areas was about 1:2:1 and the fertilization length ratio was about 1:5:1. The length of fertilization at the reproductive developmental stage was not more that 84 cm, the amount of total fertilization was not more that 0.300 kg, the ratio of fertilizer amount sowed in the primary and secondary fertilization areas was about 5:11:5 and the fertilization length ratio was about 1:3:1. The field tests results showed that when the forward speed of the fertilizer applicator was 0.38 m/s, the rotation speed of the fertilizer plate was 22 r/min, and the central angle of the leaking hole was 120°, the average relative error between the theoretical value and the actual value of the fertilization amount was 5.74%, the qualified rate of fertilizer application was 93%, which meet the requirements of banana fertilization operation. The growth of banana plants fertilized by variable rate fertilizer applicator was better than that of the conventional artificial drill fertilization. [ABSTRACT FROM AUTHOR]

To understand the agricultural production dynamics and sustainability in the hilly areas of southeast China, this paper took Dehua county, a typical mountainous area in Fujian province, as an example to quantitatively analyze the changes of input, output, environmental load and sustainability of farmland-livestock systems from 2007 to 2016, and constructed the indicators of waste emergy ratio and environmental pollution emergy negative output. The results showed that the input of the farmland- livestock system in the study area was mainly based on the purchasing emergy, accounting for 68%-79% of the total emergy input, and the emergy of water resources accounted for 21%-31%. The emergy output of livestock systems accounted for more than 72% of the total output. And the emergy density fluctuated between 2.68×1012 and 3.33×1012 sej·m-2, and emergy per person increased from 1.23×1016 sej to 1.72× 1016 sej. The net emergy yield ratio decreased by 40%, and the environmental load increased significantly, which could have been maintained since 2015. The emergy sustainability index fell rapidly from 1.14 to 0.42 after a brief rise in 2007-2010. From the indicators of construction, the proportion of system waste emergy decreased, and environmental pollution emergy output decreased by about 22%. In terms of comprehensive economic benefits and waste utilization, the sustainable development of Dehua county has gradually improved in recent years. Dehua county is currently adjusting its output structure of farmland- livestock system. It should increase the amount of feedback emergy in the system, control fertilizer and feed input, and improve waste utilization to achieve sustainable development. [ABSTRACT FROM AUTHOR]

Land use changes can affect the ecosystem services. Since the implementation of reform and opening- up policy in 1978, the transformation and development of society and economy has led to the land use transition, and furthermore led to the "ecosystem services transition". Based on the data of LUCC, net primary productivity (NPP) and statistics in 1980, 2000 and 2015, this paper analyzed the changes and spatial patterns of two types of ecosystem service, e.g., food production, carbon sequestration and oxygen release, in the Beijing-Tianjin- Hebei region by using the methods of GIS and ecosystem service values calculation, and revealed the reasons for the "ecosystem services transition". The results show that: (1) In the past 35 years, the land use changes in the study region was mainly characterized by the expansion of construction land and the decrease of cultivated land. The phenomenon of conversion of cultivated land to construction land was particularly prominent in this region. Between 1980- 2000 and 2000- 2015, the cultivated land in mountainous areas changed from decrease to increase and the forest land changed from decrease to increase. The cultivated land in dam areas continued to increase and the forest land changed from decrease to increase. Both the cultivated land and forest land in plain area continued to decrease. In 1980 and 2000, areas with high values of NPP were mainly located in mountainous areas, and in 2015, they were mainly found in plain areas. (2) From 1980 to 2000, the ecosystem services in the study area were mainly reflected by the increase of food production service and the decrease of carbon sequestration and oxygen production service. From 2000 to 2015, the ecosystem services in the region were mainly featured by the simultaneous increase of food production function and carbon sequestration and oxygen production function. The pattern of "ecosystem service transition" was "food production + carbon sequestration and oxygen production - " → "food production + carbon sequestration and oxygen production + ". (3) The main reasons for "ecosystem services transition" were the improvement of agricultural productivity, the increase of area and quality of forest land, and the increase of the quality of cultivated land and grassland. In general, the "ecosystem services transition" in the Beijing-Tianjin- Hebei region has a positive impact on food security. It is particularly necessary to pay attention to areas where both food production function and ecological function declined. Policies aimed at improving agricultural productivity should be formulated, while policies for supporting ecological restoration should be continued. [ABSTRACT FROM AUTHOR]

The mechanized seeding operation is an important part in modern agricultural production, and the net operating time utilization rate of the seeder is an important indicator to impact the efficiency of seeder unit. According to machinery unit application principle, the new term of seasonal net time utilization rate was determined in this paper, each consumed time items of seeder unit was distinguished and relevant mathematic models were established based on mechanized seeding practice and sufficient survey, such as net operating time, turning time and time of adding fertilizer and seeds and so on. Based on this, three mathematical models of net operating time utilization rate of seeding machinery units were established according to different adding fertilizer and seed ways. The experiment scheme was designed, which uses the method of multi-point synchronous tracking measurement to test the time items in the seeding process without disturbing the normal seeding process. Data of each time items of 4 typical seeding machinery units were obtained during the experiments. The statistic principle of 3ᓂ was used to distinguish and eliminate invalid experiment data. Based on the models established and effective tested data, Matlab 2012b was used to analysis the net operating time utilization rate of the 4 seeding machinery units changing with plot length and area under 3 different ways to add fertilizer and seed, the test results were expressed using Sigmaplot 12.5 software, and th quantitative correspondence between the different typical seeding machinery units and suitable operating plot area and length under the aimed net operating time utilization rate were determined. The results showed that when the aimed net operating time utilization rate of seeding machinery units is greater than 0.6, the John Deere 7 830 unit is suitable for the plots with areas no less than 6 hm² and the plot length is 1 200-1 400 m. The Valtra 171 unit is suitable for the plots with area no less than 6 hm² and the plot length is 1 000-1 200 m. The suitable plots for Changfa 504 unit are that area is no less than 1 hm²and the plot length is 500-1 500 m. The plots with area no less than 0.3 hm² and the plot length is 200-1 500 m are suitable for Huanghai 254 unit. The results can provide scientific accordance to select seeding machinery units for different plots. [ABSTRACT FROM AUTHOR]

Plastic pollution has become a global environmental concern and residual plastic films resulted from agricultural production played a significant part in it. Xinjiang in China is a region of 160 million hectares and its agricultural production is mainly in the proximal areas of the Taklamakan desert - the second largest desert in the world. Rainfall in Xinjiang is scanty but sunshine is abundant. For reducing evaporation, therefore, approximately 3.478 million hm² of croplands in Xinjiang is mulched annually by over 200,000 tons of plastic films, making Xinjiang the most contaminated region by residual plastic films in China. In this paper, we analyzed the distribution of residual plastic films in croplands in Xinjiang based on literature review, consulting and field surveys. The results showed that the residual plastic films in soil were found mainly in three layers: soil surface, 0-12 cm and 12-30 cm layers, among which 6%-8.33% was on the soil surface, 53.99%-68% in 0-12 cm layer and 26%-37.68% in 12-30 cm layer. We also analyzed the reasons behind residual film pollution, including costs of the mulch film, its mechanical properties and factors affecting its recovery. Comprehensive technologies for alleviating residual film pollution in Xinjiang were evaluated, which include improving agronomic control, using degradable films and improving film recycling. We also discussed the difficulties faced by implementation of these technologies, especially in integrating agricultural machinery and agronomical technology, mechanical recovery of the films, and systems to monitor and evaluate the residual film pollution. To ameliorate the film contamination, legal regulation for improving treatment of residual film pollution should be mandatory and new technique of integrating agricultural machinery-agronomy-agricultural film should be developed. In addition to these, methods such as boosting residual film degradation in soil, developing new plastic film, and innovating strategies to prevent and control residual film pollution, should be sought. Currently, PE mulch is still the main application in agricultural production and future research should focus on developing new degradable mulch to replace the PE mulch. In summary, mitigating residual film pollution in croplands in Xinjiang should follow 1) “restraining the increase in film production, and reducing the film stock”, 2) increasing mechanical recovery, standardizing film, optimizing cropping systems, and establishing recycling systems. [ABSTRACT FROM AUTHOR]

China is a big agricultural country, and modern agricultural production can not do well without agricultural chemicals. After nearly 70 years of development, China's pesticide industry has gradually developed from imitation of foreign varieties to combination of imitation and independent innovation. On the occasion of the 70th anniversary of the founding of China, this paper briefly summarizes the development history of agrochemicals discovery in China, and the structure, performance, discovery process, mode of action, patent and registration, and further prospect of most pesticides discovered and developed in China are also introduced. [ABSTRACT FROM AUTHOR]

With the rapid development of industrialization and urbanization as well as enhancement of geographic differentiation and diversity of man-earth areal system, functions and regional development orientations in metropolitan suburbs have shown an increasingly strong trend towards diversification. It is one of the keys to draw up the Rural Revitalization policy objectively to evaluate the multi-functional system and then sum up pattern of metropolitan suburbs. The multi-functional evaluation method of metropolitan suburbs was constructed. The multi-source spatial data, statistical data and survey data were used to evaluate the multi-functional values of the 89 towns in Shanghai. The results showed that: (1) There were significant differences in the development of multifunction among 89 towns in Shanghai. The order of mean values is listed as ecological environment function (0.7674) > economic development function (0.6054) > agricultural production function (0.5882) > life guarantee function (0.5238) > leisure culture function (0.2525). (2) The high value areas of the ecological environment were mainly distributed in Chongming Island, Western Qingpu and Southern Fengxian. The high value areas of agricultural production were mainly located in Southern Pudong, Fengxian, Jinshan, Southern Chongming and Qingpu. The high value areas of economic development was mainly located in the vicinity of central city. The low value areas of life security were mainly located in the towns close to the central city and the most remote towns. The high value area of leisure culture was mainly located in Songjiang, Qingpu and Jinshan, which are the most remote from the central city. (3) A total of 89 towns could be divided into 4 types: balanced, mixed, compound and dominant. Among the 8 subdivision patterns, only 10 towns like Pujiang town were multi-functional and presented a highly balanced development pattern, accounting for 11.24%. Thus, the final but main part of this paper envisions the innovative policies and practices in metropolitan suburbs including the diversified rural renewal, homestead regulation, and low efficiency industrial land reduction. [ABSTRACT FROM AUTHOR]

In recent years, the unreasonable use of cultivated land in China has caused a series of serious problems. Therefore, the state has put forward an important measure of "Exploring Pilot Program of Farmland Rotation and Fallow System ". Labor force is one of the main factors of agricultural production. Therefore, it is of strategic significance to further promote the national rotation fallow policy, modernization and urbanization to sum up the situation of farmer's rotation fallow land and labor force transfer and grasp the effect of fallow area on labor force transfer. Based on this, this paper uses the relevant survey data of 1542 households in six counties of Hebei, Gansu and Yunnan provinces to analyze the situation of farmer's rotation fallow land and labor transfer, and uses Tobit regression model to quantitatively analyze the impact of fallow area on labor transfer. The results show that: (1) There is a difference between the ratio of fallow households and fallow area per household in the study area, and the order of which is both Gansu > Yunnan > Hebei; (2) 62.97% of the households in the study area have the phenomenon of labor transfer, and the number of labor transfer of fallow households far exceeds that of non-fallow households; (3) The core variable, fallow area, has a significant positive impact on labor transfer; the control variable, the total household population, gender of householder, labor education level, medical expenditure, the distance from residence to highway and average wage per labor force have a significant positive impact on labor transfer, while the dependency ratio has a significant negative impact on labor transfer. [ABSTRACT FROM AUTHOR]

As a large agricultural country, there are still more than 40% of people in China engaging in agricultural production activities. In recent years, the soil erosion and desertification have been in serious state, and the arable land has decreased year by year, which means that it is very necessary to develop agricultural technology to improve crop yield per unit area. Therefore, in recent years, China has vigorously developed agricultural greenhouse cultivation which has characteristics of high input, high technology and high yield. Agricultural greenhouse cultivation is an important part of China’s agricultural production. In 2014, the area of greenhouse in China was up to 4.109 million hm2. With the promotion of precision agriculture, the technology of modern agricultural greenhouse cultivation is developing towards precision. Precision fertilization is one of the important parts of precision agriculture operation system. Due to that the structure of modern agricultural greenhouse is closed, and the planting area is limited in China, the large agricultural machinery cannot be applied to greenhouse operations, leading to that the mechanization level in greenhouse production is lower than other developed countries in the world. At present, the fertilization in greenhouse in China is still mainly relying on manpower. Because of the increasing labor cost and decreasing yield in greenhouse production, the profits of greenhouse is reduced. In the pursuit of more profit, people’s requirements of precision fertilization in greenhouse are increasingly urgent. This paper mainly introduced a small, precise and practical fertilizing machine. This machine was mainly used in greenhouse and it was intelligent and automatic. The fertilization machine used ARM9 S3C2440 microprocessor as the core of circuit control module. It was equipped with a fertilizer level monitoring alarm device, and would alarm automatically when the fertilizer level was less than 15 cm, so that the staff could add fertilizer in time. The machine used the Geneva mechanism as fertilizer metering mechanism. By controlling the pulse frequency of the stepping motor, the amount of fertilization could be controlled so as to achieve quantitative precision fertilization. The three-dimensional model of the fertilization machine was built by the SolidWorks. The intensity check was performed for its main parts of the force with simulation. All those verified that the structure could meet the requirements of hardness and intensity. The fertilization effect was simulated by the EDEM (enhanced discrete element method), a general CAE (computer-aided engineering) software applied to the discrete element method. In the simulation, the speed of the sheave was set to 10 r/min, the output time step was 0.05 s, and the total simulation time was 5 s. It was found that there weren't flying particles during the process of simulation, which showed that the selected rotational speed of the sheave and the parameter of the simulation time step were reasonable. The sheave grooves in the process of simulation were almost filled with the fertilizer particles, which proved that the device could get a good effect of fertilization and the parameter of the sheave was reasonable. The brush structure in the fertilization device could effectively get rid of the extra fertilizer particles and supplement fertilizer particles for other incompletely filled groove in order to make sure every groove could discharge a certain amount of fertilizer. The simulation results showed that the fertilization device could discharge the fertilizer particles evenly, stably and continuously. By properly controlling the rotation speed of the drive shaft, the fertilization machine could achieve the goal of precise fertilization. The results show that maximum error of fertilizer test actual value and the theoretical value is 2.42%, less than 3% under four kinds rotational speed (5, 10, 15, 20 r/min). Therefore, the machine designed in this paper could greatly improve the automation level for greenhouse production and reduce the labor intensity of fertilization in greenhouse. It has broad applicability and popularity in our facility greenhouse production. [ABSTRACT FROM AUTHOR]

The construction of the territorial spatial planning system has been fully carried out. The clear and detailed status map and data are an important basis for understanding the natural resources, and also an important support for the preparation of territorial spatial planning. However, the current land classification standards, data accuracy and application targets of the current territorial spatial data are not uniform. Based on remote sensing images, geographic conditions and Internet POI data, this paper studies one map of land and space status, synthesizes existing land classification standards and data accuracy, and constructs one map of territorial spatial planning status of Qingdao city. On this basis, the application direction of one map of territorial spatial planning is discussed, including the preliminary delimitation of "Production- Living- Ecological Space" in Qingdao city. The suitability of urban construction, the importance of ecological service function and the suitability of agricultural production were analyzed. The construction of one map of the status of territorial spatial planning plays an important role in defining the resource utilization cap and the environmental quality bottom line, standardizing the territorial spatial planning data, and supporting the preparation and management of territorial spatial planning. [ABSTRACT FROM AUTHOR]