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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]

In the process of wheat storage, rice weevil is a kind of extremely harmful moth-eaten pest, which belongs to the hidden pest that eats inside the grain, and in the growth and development process of rice weevil ( egg stage, larva stage, pupa stage, adult stage), there are different degrees of damage to wheat until the adult stage is drilled out. In severe cases, wheat grains can be eaten into empty shells, and the excrement is left inside the grains, which seriously damages the protein quality of wheat and affects the quality of flour. In order to explore the effects of rice weevil infection on wheat protein quality at different stages. In this paper, the crude protein, uric acid, protein components, wet gluten, gluten water absorption, lactic acid solvent retention capacity (SRC), sucrose SRC, sulfhydryl (-SH), disulfide bond (-S-S-), protein secondary structure, gluten protein microstructure of the wheat infected by rice weevil and the color and texture characteristics of the corresponding whole wheat noodles were measured and analyzed. The results showed that the growth and development of rice weevil in wheat and the damage of wheat would cause a series of changes in wheat protein, which was manifested in the deterioration of physical and chemical properties and morphological structure. With the growth and development of rice weevil inside the wheat kernels, the content of crude protein in wheat grains increased significantly, the content of wet gluten, gluten water absorption, lactic acid solvent retention SRC, sucrose SRC, -SH and-SS-decreased, The proportion of wheat protein components and secondary structures, which are very important for wheat, also changed significantly ( P<0.05 ), and the edible quality and nutritional value of wheat also decreased. The microstructure of gluten protein showed that with the growth and development of rice weevil in wheat grains, the surface roughness of gluten increased, and the fracture surface and burr increased. After reaching the adult stage, some gluten structures had been seriously broken and could not be identified. After making whole wheat noodles, the color of noodles deepened, L* value and cooking loss rate increased, a* value, b* value, hardness, adhesion, elasticity, cohesiveness, chewiness and resilience decreased. The experimental results further elucidated the deterioration mechanism of wheat damaged by rice weevil, and provided a theoretical basis for the quality improvement of wheat during storage and the insect infected wheat. [ABSTRACT FROM AUTHOR]

[Objective] The present paper aimed to explore the grain production pattern and influencing factors in the major production areas, provided a certain basis for stabilizing the overall situation of national food security and formulating differentiated grain policies. [Method] By means of concentration degree, gini coefficient, logarithmic mean divisia index and cultivated land pressure index, quantitatively analyzed the factors influencing the increase of grain production in major grain producing areas from 2000 to 2020, such as the change of grain production center, variety structure, contribution to increase production, resource bearing capacity and production cost. [ Result] ( i) From the change of grain production center, more than 95 % of the grain increment came from the major grain producing areas, and the major producing areas in the north contributed more to the increase, especially Shandong, Henan and Heilongjiang, which occupied the top three areas of grain output and sown area for a long time. (ii) In terms of the production centers of different food crops, the production centers of wheat, com and beans were stable in the major grain producing areas in the north for a long time, while the production centers of rice and potato were mainly concentrated in the major grain producing areas in the south, but the production centers of rice gradually showed a trend of northward deviation. (iii) From the perspective of contributing factors, the grain increase in the major grain producing areas mainly depended on the increase of yield per unit area, and the contribution rate of yield per unit area to grain increase reached 61. 16%. The grain increase in the major grain producing areas in the north was due to the combined effect of cultivated land area, multiple cropping index, grain crop proportion and yield per unit area. Due to the decrease of cultivated land area in the major grain producing areas in the south had a negative effect on grain increase, the grain yield increase was more dependent on unit yield increase and multiple cropping index. (iv) From the perspective of resource carrying capacity of grain production, the dilemma of uneven distribution of water and soil resources has not been improved for a long time. The constraints of water resources in the major grain producing areas in the north were increasingly strengthened, while the pressure of cultivated land resources in the major grain producing areas in the south was continuously high. ( v) From the change and structure of grain production cost, the average grain production cost in the major grain producing areas was rising continuously. The land cost in the major grain producing areas in the north was higher, and the labor cost in the major grain producing areas in the south was higher. The grain production cost in the major grain producing areas in the north was higher than the whole country and the major grain producing areas in the south for a long time, and the rising rate was slightly faster than that in the major grain producing areas in the south. [Conclusion] Establishing the food security responsibility mechanism shared by the producing and marketing areas, constructing the differentiated compensation mechanism; Strictly observing the grain sown area, adjusting the structure of regional grain varieties; Consolidating scientific and technological support for grain increase, promoting coordinated development of water and soil resources and grain production; Taking multiple measures to improve grain production efficiency, and enhancing the enthusiasm of various subjects to grow grain. [ABSTRACT FROM AUTHOR]

Water is the lifeblood of agriculture. Different from land resources, water resources can flow across regions. Based on the perspective of ‘physical water and virtual water’ flow and using the panel data of 31 provinces (autonomous regions and municipalities) in China from 2004 to 2020, this paper used the dynamic spatial Durbin model to estimate the impact of regional grain trade on the pro⁃ portion of grain planting and that of rice, wheat, and corn in the context of inter-basin water transfer. The results showed that: ① For grain output areas, the impact of ‘physical water and virtual water’ flow decreased, the overall proportion of grain planting increased, and the proportion of corn planting among the grains decreased. It showed that the increase of water resource pressure in grain output areas played a greater role in promoting the induced technological change of grain production and strengthening the regional production division than limiting them, and there was a ‘paradox of irrigation efficiency’, that is, the progress of water-saving technology led to the increase of high water consumption crops. ② For grain input areas, the impact of ‘physical water and virtual water’ flow increased, the proportion of grain planting decreased, the proportion of short-term rice and corn planting increased, the proportion of rice (high water consumption crop) planting increased more, the proportion of long-term rice and corn planting decreased, and the proportion of corn (low water consumption crop) planting decreased more. It showed that the regional division of labor and strengthening of grain production reduced the proportion of grain planting in grain input areas, but the internal structure of grain was developing in the direction of more water consumption. ③ Under the current ‘physical water and virtual water’ flow, the grain input areas had a negative spatial spill⁃ over effect on the grain planting proportion in the output areas and the corn planting proportion among the grains, which showed that the reduction of water resource pressure in the grain input areas had a negative impact on the grain production in the grain output areas, and intensified the phenomenon of ‘paradox of irrigation efficiency’ in the internal structure of grain. The grain output areas had no significant impact on the grain planting proportion in the grain input areas. In the short term, the planting proportion of rice and corn was reduced, and the planting proportion of rice, a high water consuming crop, was reduced more, the planting proportion of rice and corn increased in the long term, and the planting proportion of corn, a low water consuming crop, increased more, indicating that the grain out⁃ put areas promoted the development of the internal structure of grain in the grain input areas in the direction of water saving. Finally, this paper puts forward the policy implications of implementing the overall management of ‘physical water and virtual water’, vigorously promoting the development of water-saving agriculture in grain output areas, and establishing regional grain virtual water compensation systems. [ABSTRACT FROM AUTHOR]

【Objective】This paper explored the temporal and spatial expansion characteristics and industrial operation mode of farmers’ cooperatives in different topographical areas of Chongqing, mastered the development law of farmers’ cooperatives in Chongqing and analyzed the differences in the selection of different industrial modes, in order to provide data support for promoting the classified cultivation of cooperatives and the formulation of differentiated support policies.【Method】This paper used 2528 farmers’ cooperatives in Chongqing as a sample, comprehensively used terrain distribution index, standard deviation ellipse and other methods to analyze the temporal and spatial patterns and expansion characteristics of cooperatives of different industrial types in four types of terrain. And combined with the questionnaire survey, combed and refined the cooperative operation mode. 【Result】（i） The development of farmers’ cooperatives in Chongqing showed four growth stages in general, with slow growth from 2002 to 2006, rapid growth from 2007 to 2010, the growth rate slowed down from 2011 to 2014, and the growth rate from 2015 to 2018 has dropped significantly. From the perspective of topographical area, the growth rate of Area Ⅳ is the fastest, followed by Area Ⅱ and Area Ⅰ, and Area Ⅲ had the slowest growth rate.（ii） The growth advantages of cooperatives in different industries vary significantly. The growth advantage zone of livestock and poultry industry was Area Ⅳ. The growth advantage zone of the fruit and vegetable, grain and oil, and comprehensive industries were Area Ⅰ and Area Ⅱ. The growth advantage zone of the flower, tree, tea, and peppercorn industries are Area Ⅱ, the tobacco and Chinese medicinal materials industries are Area Ⅲ and Area Ⅳ.（iii） Except for the grain and oil industry cooperatives in the southeast-northwest direction from 2002 to 2006, the rest of the industrial cooperatives had a southwest-northeast distribution at various stages.（iv） There were six main modes of cooperative industrial operation, the livestock, poultry, fruit and vegetable, flower and tree and grain and oil industries use the ‘company + farmers’ cooperative + base + farmer’ model. The ‘company + farmers’ cooperative + farmer’ model was used by fruits and vegetables, flower and tree, grain and oil industries. The industries that use the ‘farmers’ cooperative + base + farmer’ model include fruit and vegetable, flower and tree industries, and the industries that use the ‘Internet+ farmers’ cooperative + farmer’model include livestock, poultry and other industries. The industries of the ‘farmers’ cooperative + farmer household’ model include fruit and vegetable, grain and oil industries, and livestock industry using the model of ‘company + farmers’ cooperative + base + family farm’. 【Conclusion】The number of farmers’ cooperatives in Chongqing is growing, and the advantageous area of different industries has a difference, and it has evolved in the northeast direction, and the operation mode of each industry is diverse. According to the spatio-temporal expansion characteristics of the cooperative and the local conditions, we should accurately find the mode of industrial operation and promote the steady development of cooperatives. [ABSTRACT FROM AUTHOR]

The aims of this paper is to illustrate the importance of grain production in China's food security strategy based on the three Northeastern provinces (NEP) in the new period, which quantitative assessment of climate change under the background of the loss caused by meteorological disasters of regional food production is clarify. In this paper, using grain planting area, yield and agricultural disaster statistics from 1981 to 2020, comparison analysis grain production and disaster characteristics between NEP and the whole country respectively. The disaster-yield assessment model was used to estimate the disaster-yield loss and final yield of the NEP by inputting disaster data in recent 10 years, and the sensitivity and stability of the disaster-yield assessment model were re-tested. The results showed that :(1) from 1981 to 2020, the grain planting area and total output in NEP increased significantly, and the proportion of the total output of NEP increased steadily, and the proportion of the total output of the three northeast provinces reached 1/5 of the total output of the whole country by 2020. (2) The disaster situation in NEP showed a significant trend of first increasing and then decreasing. The incrasing of average grain yield during the past 40 years was 65.96kg⋅ha-1 and 252.5kg⋅ha-1 per year for NEP and the whole country, while the incrasing of average grain yield during the past 10 years was 52.6kg⋅ha-1 per year for NEP significantly. (3) From 2011 to 2020, the average affected area and affected area in China were 23704.5x10³ha and 11204.7x10³ha, respectively, and 3899.1x10³disasters of the whole country and the three northeastern provinces were significantly lower than those of the previous three years, making it the decade with the least severe disasters in 40 years. (4) The simulation accuracy of the disaster-yield assessment model was high. The linear regression coefficients (R²) of simulated grain yield and measured grain yield in Heilongjiang, Jilin and Liaoning provinces were 0.98, 0.90 and 0.88, respectively. The slopes were 1.05, 1.02 and 0.98 (P < 0.01), respectively. The loss rate of grain yield due to agro-disaster was 10.4%, 17.9% and 18.0% respectively in the three province, while which was more than 8.0%, 17.0% and 16.0% for 20a.years. (5) The model slightly overestimated the grain yield of Jilin and Liaoning in recent 10 years due to the overall light disaster situation. Based on the data from 1981 to 2010, the regional grain disaster loss assessment model was proved to be able to evaluate the loss of grain yield caused by meteorological disasters well, and had the performance of predicting grain yield, and has the feasibility of operational application. The impact of meteorological disasters on the grain output in northeast China is higher than the average level of disasters in the whole country. Considering that the grain output in Northeast China accounts for a high proportion of the national grain output, preventing the risk of agro-meteorological disasters in Northeast China in the new period is of great importance to guarantee the national food security. [ABSTRACT FROM AUTHOR]

【Objective】 The study on the change characteristics of cultivated land area and its influence on grain production pattern in key watersheds aims to provide reference for promoting the sustainable use of cultivated land and coordinating the relationship between food security and economic development. 【Method】 Taking 82 counties in key watersheds of Sichuan Province as the research unit, using mathematical quantization model and GIS spatial analysis method, this paper explores the spatiotemporal evolution characteristics of cultivated land area and its influence on the change of grain production pattern in the study area in recent 20 years. 【Result】 (1) From 2001 to 2020, the cultivated land area in the key watersheds of Sichuan Province increased by 915,700 hm², with an increase rate of 37.39%, but showed a changing trend of “increase→ basically unchanged→ decrease→ basically unchanged” in different economic development periods. (2) The change of cultivated land area showed a spatial agglomeration state of “high-value cluster area” and “low-value cluster area” in the key watersheds of Sichuan Province, and the changes in quantity of these areas showed an inverted “N” type fluctuation trend in different economic development periods. (3) The spatial transfer types of grain production (grain production transfer out area, grain production transfer into area and grain production stability area) in the key watersheds of Sichuan Province showed a fluctuating trend of increase and decrease in quantity. In general, the area of grain production transferred out and transferred into increased by 13.42% and 13.41%, respectively, and the change trend was basically unchanged. However, the grain production stability area decreased significantly, down by 26.83%, and there was regional degradation in grain production. (4) The change of cultivated land area is an important cause of the spatial transfer of grain production in the key watersheds of Sichuan Province, and the counties that are sensitive to the change of cultivated land area show the characteristics of centralized and multi-point distribution. 【Conclusion】 The change of cultivated land area and its impact on grain production pattern in the key watersheds of Sichuan Province from 2001 to 2020 fluctuated significantly in different periods of economic development. Therefore, countermeasures and suggestions are put forward to strictly implement the cultivated land use control system, strengthen the cooperative management of regional competent departments, establish the long-term benefit compensation mechanism of cultivated land conservation, and construct the cultivated land security early warning and control mechanism. [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]

The aim of this paper is to assess the loss of grain production caused by agrometeorological disasters in the Inner Mongolia Autonomous Region (IMAR), which is an important grain production base of China. The disaster-yield assessment model was formed and verified using grain production, yield, planting area and agrometeorological disaster conditions data of the IMAR from 1981 to 2020, and the loss of grain yield caused by meteorological disasters was assessed by this model. The results showed that grain production, yield and planting area observed an escalating trend from 1981 to 2020, and the rate of increase was 78.85×104t·y-1, 100.97kg·ha-1·y-1 and 74.48×10³ha-1·y-1. The covered and affected area of agrometeorological disasters for the IMAR and National both increased and then decreased during the 1981-2020 period. Drought was the most important agrometeorological disaster in the IMAR, and the covered and affected area was 64.10% and 62.45%, respectively, accounting the total covered and affected area of all kinds of disasters in 1981-2020. The grey correlation analysis showed that drought had the highest correlation with grain yield at the level of disaster covered and affected rate, and hail had the highest correlation with grain yield at the level of disaster destory rate. The disaster-yield assessment model constructed by this study was of high simulation accuracy, and the linear regression coefficients (R²) and the slop between the simulated and measured grain yield was 0.99 and 0.98, respectively (P < 0.01). The average relative simulation yield was 0.20% and relative simulation error of the following year grain yield was 2.49%. Grain yield loss rate due to disaster in the IMAR decreased (R²=0.77，P<0.01) from 1981 to 2020 with a rate of 0.48 percentage points·y-1, and average grain yield loss rate was 14.79% and there were 68.42% of years which grain yield loss rate above 10%. The disaster-yield assessment model of the IMAR formulated in this study can simulate and predict grain yield, and assess the loss of grain yield due to disasters, which can meet the needs of agrometeorological services. [ABSTRACT FROM AUTHOR]

[Objective] The extraction and change monitoring of cultivated land information is one of the hotspots of remote sensing application research. Northern Guangdong is the main grain base of Guangdong Province, and is the key area of cultivated land change monitoring by business management departments.[Method] In the present paper, using GF-2 and Sentinel-2 remote sensing images, combined with the phenological period of late rice in the study area, the vegetation index, humidity index, brightness index, color index and texture features were extracted for multi-scale segmentation, and the multi-scale image of paddy field extraction was constructed. The index difference image and time series multi feature difference image were classified to extract the paddy field area and evaluate the results.[Result]（i) The highest extraction accuracy of paddy field in time series multi feature difference image was 0.98,and the minimum difference between paddy field area and late rice sowing area was 240.05 hm2,and the best paddy field extraction effect was based on time series multi feature difference image;（ii）The difference of index feature needed to use the key phenological characteristics of crops and combine with multi-scale segmentation of image to improve the accuracy of paddy field extraction;（iii）The machine forest method has faster operation speed and higher classification accuracy in data classification with high dimensional features. [Conclusion] The research of the paper is to explore the method of high-resolution remote sensing in rapid and accurate updating of cultivated land information, which can provide support for the application of cultivated land management business. [ABSTRACT FROM AUTHOR]

[Objectives] In order to analyze the influence of different three-dimensional(3D) point cloud density on the measurement accuracy of grain volume with the size of scraper,the optimal point cloud density for small volume measurement of grain was obtained. [Methods] In this paper,a grain volume measurement device based on laser triangulation was designed by using a line laser sensor under laboratory conditions. LabVIEW software programming was used to achieve motor motion control,image acquisition and processing in the camera,3D coordinate extraction of grain surface point cloud,data storage,volume calculation of grain and 3D point cloud visualization,etc.,focusing on the laser center line coordinate extraction method and point cloud interpolation processing method. Based on the verification of the measurement system performance,the optimal point cloud density of rice was obtained by synthetically analyzing the mean relative error and maximum relative error of the number and volume measurement of grain point clouds under 14 different point cloud densities. [Results] In the performance verification of the system,the average relative error and the minimum relative error of the measurement results were 0.44% and 0.28%,respectively. Considering the number of point clouds,accuracy and stability of grain volume measurement,the optimal density of three-dimensional point clouds for rice volume measurement was 11 mm×11 mm. [Conclusions] The laser triangulation in this paper can accurately measure the grain mass,and the optimal point cloud density of the grain volume with the size of the scraper was obtained. [ABSTRACT FROM AUTHOR]

Although scarcity of irrigation water restricts grain production, it can promote agricultural technology progress to increase supply elasticities of grain. To shed light on the comprehensive effect of irrigation water pressure on grain production structure, this paper explores the effects of irrigation water pressure, grain price changes and their interaction on the yields of different crops based on heterogeneous coefficient Nerlove model and panel data of 27 provinces from 2002 to 2017. The results show that: (1) The direct effect of irrigation water pressure on grain production structure is increasing proportion of corn yield and reducing proportions of other crops yields. Specifically, the magnitude of that impact is in a descending order from rice, potatoes, beans and wheat. (2) The indirect effect of irrigation water pressure on grain production structure is decreasing supply elasticities of wheat, beans and potatoes while making supply elasticities of rice and maize even larger, which contributes to the increase of proportions of rice yield and corn yield. (3) With growth of irrigation water pressure from 2002 to 2017, its comprehensive effect on grain production structure makes a significant increase in proportion of corn yield and a significant decrease in proportions of beans yield and potatoes yield. Regional analysis reveals an increase in yield proportions of maize and rice in main grain production areas of Northern China, leading to more irrigation water consumption in this region where scarcity of water is severer. And this finding of our paper is a support for "the paradox of irrigation efficiency". [ABSTRACT FROM AUTHOR]

[Objective] The present paper aimed to explore the suitable straw returning methods for grain production in the Zitong River Basin. [Method] The impacts of straw non-returning (BR), straw mulching (FR), straw burying (MR) and straw heap back to field (DR) on soil fertility and grain production were investigated. [Result] Total nitrogen, available phosphorous and organic matter contents treated with FR, MR and DR increased by 18. 6 -38. 2 mg/kg, 5. 6 - 6 . 5 mg/kg, 0. 6 -2. 3 g/kg compared to BR treatment, respectively. The yield of rice, wheat, reap and corn increased by (1. 1 - 1. 3) x 10³, (0. 7 - 0. 8) x 10³, (0. 3 - 0. 5) x 10³, (0. 7 - 1. 0) x 10³ kg/hm², respectively. Returning straw to the field has significant effects on soil nutrients and grain yield. The contents of total nitrogen, available phosphorous and organic matter in DR treatment were significantly higher than FR and MR treatment, and the yield was slightly higher than FR and MR treatment. Rice, rape and corn all achieved the greatest economic benefits under DR treatment, with an average increase of 15. 6%, 27. 2%, 32. 1% compared with FR and MR, respectively. That of wheat on FR and FR was the same, 26. 7% higher than MR treatment. [Conclusion] Comprehensive analysis of the effect of soil fertility in the cultivated, grain yield and economic benefits, heap back to field is more conducive to the fertilization and grain production of the rice, rape and corn fields in the Zitong River Basin, and the straw mulching and heap back to field are both beneficial to the small grain production in the wheat field. [ABSTRACT FROM AUTHOR]

Wheat is one of the most important grain crops in the world. The stability of wheat yield is crucial to global food security. The final yield of wheat can be calculated by the number of ears per unit area. Using deep learning technology to accurately and automatically count the number of wheat ears can save a lot of manpower and material resources. The images of wheat ears from four different wheat varieties during grain filling period were collected, and 296 images with a total of 14 964 ears of wheat were selected to construct the WEE data set. The method of point labeling was used to label the wheat ears in the images. In order to quickly and accurately count the number of wheat ears in complex crowded scenes, a method of estimating the density map and counting the number of wheat ears in field wheat images was proposed. Firstly, histogram equalization and threshold segmentation were used to preprocess the collected field wheat images to reduce the influence of light and some complex backgrounds on counting. Then, according to the characteristics of dense wheat growth at grain filling period, the Congested Scene Recognition Network (CSRNet) was introduced to construct the wheat ear density map estimation model. The CSRNet network was composed of front-end and a back-end networks. The front-end network uses the pre-training model VGG16 to extract the features of the wheat images, and the back-end network uses the dilation convolution to generate the distribution density map while expanding the receptive field. In order to improve the accuracy of the model in the training process, the transfer learning method was used to pre-train the model by using the public wheat image data set, and the collected wheat image data set was used to adjust and optimize the model parameters. The trained model was used to generate the wheat ear density map of a single wheat image, and the wheat ears were counted according to the sum of all density values in the density map. Finally, according to the test data of a single wheat ear image, a wheat ear counting function was constructed to estimate the number of wheat ears in the field. Experiments were conducted on a total of 296 wheat images collected from four varieties (Annong170, Sumai 188, Lemai 608 and Ningmai 24). The Mean Absolute Error (MAE) and Root Mean Square Error (RMSE) were 16.44 and 17.89, respectively. The correlation coefficient R² between the ear count values and the true values of the four varieties of wheat was about 0.9, indicating that the method in this paper has a higher accuracy for counting wheat ears in a single image. In addition, the experiment of estimating the number of wheat ears in the field showed that the error of estimation of wheat ears was smaller with the increase of area. The results of this study can provide the possibility of automatic estimation of the number of wheat ears in practical application process, and also provide a reference for wheat yield estimation. [ABSTRACT FROM AUTHOR]

This paper aims to investigate the spatial distribution, temporal change and policy proposal of the cultivated land pressure in China. Considering the relationship between the quantity of cultivated land and population, the model of cultivated land pressure index put forward by Professor Cai Yunlong, can quantitatively measure the tension of cultivated land resources in a region. But the difference of cultivated land quality and utilization in different regions was not considered in this model. Therefore, this paper adopted the quality coefficient to expand the cultivated land pressure index, which can reflect both the quantity and quality of cultivated land. Moreover, most of the existing relating studies focused on shorter time series or smaller research fields, few studies have been conducted with long time series data like the years of 1978-2015 in this paper, and little research about spatial-temporal change of cultivated land pressure has been done at different scales across the whole China. So, this paper used the modified model to calculate the cultivated land pressure index at different levels i.e. the whole country, 4 major economic regions and 31 provincial administrative regions from 1978 to 2015. And based on the above-mentioned research data, by using the methods of comparative analysis, clustering analysis and barycenter analysis, this paper analyzed the temporal changes and spatial distribution differences of cultivated land pressure index at the 3 spatial scales and put forward some proposals for cultivated land protection. The study showed that: 1) The changing trend of the cultivated land pressure index in China can be approximately divided into 4 stages: fluctuant declining period from 1978 to 1984, relatively stable period from 1985 to 1997, rapidly rising period from 1998 to 2003 and rapidly declining period from 2004 to 2015. 2) The regional difference of cultivated land pressure is very obvious. In more detail, the cultivated land pressure in the eastern region of China increases gradually, and in the western region of China, the cultivated land pressure is always high, while it is basically stable at a safe state in the middle and northeastern regions of China. 3) The barycenter of cultivated land pressure in China gradually moves to the southeast over time. 4) Thirty-one provincial administrative regions can be divided into 4 types by using the hierarchical clustering method, namely high-pressure type, medium-pressure type, low-pressure type and non-pressure type. 5) Finally, aiming at different types or degrees of cultivated land pressure, suitable countermeasures should be taken to alleviate the cultivated land pressure effectively so as to guarantee the grain supply in all regions of China, such as purchasing the indicators of cultivated land compensation in other provinces or controlling the population inflow moderately for economically developed provinces of high pressure, carrying out land consolidation and rehabilitation actively or increasing agricultural investment for ecologically fragile provinces of high or medium pressure, improving farmland infrastructure or transporting grain to the food shortage areas or offering the indicators of cultivated land compensation to other provinces with insufficient cultivated land reserve resources for low-pressure or non-pressure provinces located in major grain producing areas, and so on. [ABSTRACT FROM AUTHOR]

【Objective】The agro-pastoral ecotone at Inner Mongolia and Liaoning border is an important part of the farming-pastoral ecotone in northern China, and it is also the ecological barrier of the commodity grain base and heavy industry production base in Liaoning. 【Method】Maize was the main crop in this area and play an important role in grain production. In this paper, the maize in the agro-pastoral ecotone at Inner Mongolia and Liaoning border was used as the research object, and the differences of C and N contents in various organs of maize under the two methods of irrigating and mulching were analyzed. 【Result】Under the two planting methods, the C content of the stem was the highest and the C content of the root was the lowest; The N content of leaves and ears was higher, the N content of roots was lower; the C/N of roots and stems was higher, and the C/N of leaves was lower. Compared the two planting methods: The C content of leaf in the irrigated land was significantly higher than that in the mulched land; the N content of the stem was significantly lower than that in the mulched land; The C/N of stem and leaf was significantly higher than that in the mulched land; The soil organic matter was significantly lower than that in the mulched land. 【Conclusion】Comparing with irrigated land, the mulching method can more effectively maintain soil nutrients, reduce water waste and also improve maize quality and yield. [ABSTRACT FROM AUTHOR]

Common buckwheat, a traditional edible and medical plant, which grain is an important storage organ. However, types of husk-cracking of commom buckwheat and it's germination effects is a scientific and technological problem to be solved. In the present study, five samples of common buckwheat were used as materials. The grain model of common buckwheat was established and the types of pericarp cracking were classified; at the same time, through the paper bed germination method, testing the seed germination rate, the radicle and hypocotyl length. The results were as follows:(1)There are five kinds of cracking types in the grain of common buckwheat, which are longitudinal complete dehiscence type(LCD), semi-dehiscent micropyle(SDM), semi-dehiscent mid-ridge(SDMR), semi-dehiscent hilum(SDH)and transverse cracking type(TC);(2)Five test common buckwheat pericarp cracked type germinates about 12 hours earlier than the pericarp intact type;(3)The early germination rate of common buckwheat varieties with pericarp cracking was higher than that of the corresponding pericarp intact type, however, 48 h later, the germination rate of seeds with intact pericarp continued to increase, and exceeded that of all pericarp cracked types;(4)On the extension characteristics of radicle and hypocotyl, although the growth rate of radicle and hypocotyl of pericarp cracking type were faster than that of intact type of pericarp, the ratio of radicle to hypocotyl of intact pericarp type was higher than that of pericarp cracking type;(5)Different type of pericarp cracking had different effects on seed germination, from big to small, which is SDM, SDH, LCD, SDMR and TC, respectively. Different type of pericarp cracking had different mildew rate, from big to small, which is SDH, LCD, SDMR, SDM and TC. There are five common cracking types in common buckwheat grain pericarp; although pericarp cracking can improve the early germination rate of common buckwheat seeds and promote the early extension rate of radicle and hypocotyl, it can reduce the germination rate and the ratio of radicle to hypocotyl growth of common buckwheat as a whole, it may not be conducive to the formation of strong seedlings and whole seedlings in the field. [ABSTRACT FROM AUTHOR]

In China, ultra-small-scale agricultural production remains low agricultural income which cannot afford adequate livelihood and as well meet their basic needs of rural households. Smallholder production systems have seriously hindered the sustainable development of China’s agriculture. Family farms with a moderate land scale is a way to develop China's agriculture. Moderate land scale of China's agriculture is affected by multiple factors like average social income level, grain production income, etc. So moderate land scale is a dynamic value. This paper aimed to assess moderate land scales of grain family farms at the municipal level in China based on the method of income equalization. The research findings are as follows. The moderate land scale of grain family farms was 13-14 hm2 in 2016-2017, equivalent to the local household contracted area of 30 times. According to the policy formulated by China’s central government in 2014, the moderate scale of one family farm should be 10-15 times of average household contracted area. That is, the current standard of moderate scale is low. Mainland China can be divided into 9 districts and 38 sub districts according to the different types of land scale management. The moderate scale of the Northeast Region and the Inner Mongolia Plateau Region are 15-17 hm2, the North China Plain Region is about 10 hm2, the Lower Yangtze River Region and the Southeast Coastal Region are 7-9 hm2, the Southwest Mountainous Region is 6 hm2, the Loess Plateau Region is 18 hm2, and the Northwest Arid Region is 25 hm2 . The scale of the Qinghai-Tibet Plateau Region is the highest, 30 hm2 . The ratio of the moderate scale to the average cultivated land area per household in the Inner Mongolia Plateau Region is 8, and the ratio in the North China Plain Region and the Lower Yangtze River Region is about 35. It is difficult for China to achieve scale management on the whole, and the difficulty gradually decreases from the southeast coast to the northwest inland. The boundary line extends from Beijing to Nujiang Lisu Nationality Autonomous region, Yunnan. The moderate scales of grain family farms in the southeast region of the line are mostly 6-10 hm2, and it is difficult to achieve. In contrast, the moderate scales in the northwest region of the line are mostly above 15 hm2, and it is easy to achieve. China's scale management reform is at the initial stage. The promotion speed of scale management should not be fast to avoid social unrest. It is recommended to raise the standard of moderate management scale to the range of 15-20 times, and the standard can be adjusted according to the actual situation in different regions. The government should also promote institutional innovation to reduce high land transfer transaction costs. System reform can be carried out in three aspects. Firstly, the government should promote farmers who do not rely on agriculture to actively release land resources; Secondly, the local governments should actively play a coordinating role to promote land centralization and scale management; Finally, a unified and perfect land circulation market should be established [ABSTRACT FROM AUTHOR]

In the recommendation system, this paper proposed an XGBoost recommendation algorithm to integrate collaborative filtering based on the cold-start problem of users. Firstly, it used coarse grain to recall according to the collaborative filtering recommendation algorithm based on user similarity, and got a recall set of some users. Then it used XGBoost algorithm to predict the items in the recall set. Secondly, for users with cold-start problems, it could directly use XC Boost algorithm to predict the items in the candidate set. Finally, the algorithm used the online evaluation data set of CCIR2018 personalized recommendation evaluation, and put the recommendation results on the online platform provided by Zhihu for evaluation. The evaluation results show that the proposed algorithm can solve the cold-start problem of users with high efficiency and accuracy. It achieves remarkable recommendation effect in the online evaluation platform. [ABSTRACT FROM AUTHOR]

Accurate detection of historical status of granary is helpful for its management. Based on statistical analysis of grain temperature in granary, this paper presents a method to detect the storage status of the granary in attempts to resolve the problem of time-consuming and tediousness faced by inventory inspection. Warehouse with state of being empty, filled with fresh grain and ventilation was used as an example. Analysis of the distribution of statistical characteristics of historical grain temperature showed that the empty warehouse could be detected using the difference in temperature between the upper and lower adjacent layers of the grain bulk as well as the variation of the grain temperature; the fresh grain could be detected by the difference in temperature between adjacent layers and the difference in standard deviation of the grain temperature; the ventilation could be detected by the change in the grain temperature and the standard deviation difference of the grain temperature. The threshold intervals of the characteristic parameters of the three states were set preliminarily from analysis of the statistical characteristics of the grain temperature. Based on the threshold intervals, three optimal levels were selected and the orthogonal experiments of two-factors and three-levels were designed. In the same grain depot with 11 granaries, new and ventilated granaries were chosen for the orthogonal experiments. The optimal threshold range of the statistical characteristic parameters were determined by analyzing the statistical characteristics of the historical grain temperature changes in the 11 granaries. Multi-variable decision tree for inventory status detection was designed and the optimal threshold of the characteristic parameters of the multi-variable decision tree were as follows. The temperature difference between adjacent layers for empty granary status detection was [-0.12, 0.12] ℃. The temperature difference between adjacent layers was more than 0.02 (or 0.03) ℃, and the standard deviation was less than 2.0 (or 2.1) ℃. The average temperature change rate in the parameters for detecting the ventilation characteristics was [-0.5, 0.5] ℃/d and the standard deviation change rate was [-0.21, 0.21] ℃/d . Finally, seven granaries in different provinces were selected to test the detection method. The results showed that the accuracy and recall rates were 78% and 82% respectively for the empty granary state, and 74% and 70% respectively for new grain state, and 91% and 88% respectively for ventilated state. The test results showed that the proposed method detected granary at empty and ventilated state more accurate than at new grain state. [ABSTRACT FROM AUTHOR]

[Objective]The purpose of this paper is to study the effect of grain size and weight on the total anthocyanin content(TAC) of ‘ Yungu No. 1 ’ . [ Method] Anthocyanins from black rice were extracted by extraction method, and the absorbance value of solution was determined by pH differential method. Date analysis was carried out by statistical method. [ Result] There were significantly positive correlations between TAC of black rice and grain size and weight (P<0.001). Grain thickness had the highest correlations with TAC, followed by grain weight, width and finally the length. The difference of TAC was not obvious when grain thickness exceeded 1.80 mm, and there was an intermediate transition state which the thickness between 1.70 to 1.80 mm. A new comprehensive variable was extracted by the Partial Least Squares (PLS) analysis, which explained 96.3 % of the x-variability and 78.8 % of the y-variance, respectively, and the prediction rate for TAC was 77. 1 %. [ Conclusion] Grain size and weight not only affect the appearance quality and physical properties of rice, but are also closely related to some nutrient contents. [ABSTRACT FROM AUTHOR]

[Objective]This paper aimed to explore the effects of fertilization on the growth and development of spring maize and the absorption and utilization of its nutrient elements. [Method] A field experiment was designed to study the effects of different fertilization patterns on the growth characteristic and nitrogen use efficiency of corn for continuous three years. [Result] With the growing period, the contents of chlorophyll, carbohydrate and protein in the leaves of corn by fertilization and CK showed a similar increasing trend, ordered as FP > OTP > CK in the same period. The plant height, stem diameter, leaf area index, 100 grain weight, panicle grain number and panicle grain weight of corn at mature stage all showed FP > OTP > CK. Further, superoxide dismutase (SOD) , catalase, peroxidase activity of corn showed a similar increasing trend, while the leaf malondialdehyde content decreased with the fertilizer, and the difference between fertilizer and CK gradually expended with the growing period, suggesting that fertilization promoted the synthesis of spring maize growth and leaf physiological characteristics, especially in the mature period of performance. The accumulation of nitrate nitrogen in soil under energy application was mainly concentrated in the 0 - 10 cm soil layer, and the nitrate nitrogen content in the 0 - 10 cm soil layer accounted for 15.32 % -35. 64 % in soil (0 -30 cm soil layer) , supporting the surface-aggregation. Total nitrogen uptake under fertilization treatment showed FP > OTP>CK, with significant differences (PcO.05). Compared with CK, the total nitrogen uptake of spring corn under FP and OTP treatment increased by 58. 9 and 82. 9 kg/hm2 , respectively, and the nitrogen utilization rate was higher under FP treatment. [Conclusion] Altogether, it was considered that the fertilization mode significantly increased the grain weight and grain number per ear of spring corn at the ma-ture stage, indicating that fertilization promoted the increase of grain number per ear of spring corn to some extent and thus increased the yield of spring corn. [ABSTRACT FROM AUTHOR]

China achieved ten-year consecutive grain production increase which had never appeared in history no matter in China or in the world during 2003-2013. Till 2015, twelve-year consecutive grain output increase has been achieved. The purpose of this paper is to detect the spatiotemporal patterns and the main investigated contributions of grain output increase at the county level during 2003-2013. Based on factor contribution analysis and GIS, this paper analyzed the spatiotemporal patterns of grain output increase at the county level, taking use of planted area output and yield per unit area. The results showed that: 1) the grain output increase had appeared in more than 75% of the counties in China, most of these counties located in the major grain-producing regions in Northeast Plain and the Huang-Huai-Hai Plain. At the scope of grain output increase accumulation, half of national grain output increase concentrated in the top 198 counties (which accounted for 8.49% of counties in China), and 80% of national grain output increase concentrated in the top 550 counties (which accounted for 23.60% of counties in China); 2) the polarization of grain output increase at the county level was significant: the counties in hysteretic growth and overspeed growth occupied 33.98% and 33.15% of counties respectively, in which the overspeed counties mostly concentrated in Songnen Plain, Sanjiang Plain, the Huang-Huai-Hai Plain, Jianghan Plain, Poyang Lake Plain, Loess Plateau, and Xinjiang Uygur Autonomous Region; 3) as for most counties whose grain output increased during 2003-2013, the expansion of planted area and the promotion of yield per unit area were both important reasons. There are 893 counties where the former played more important role, mainly located in Northeast Plain, the west of Inner-Mongolia Plateau, Hexi Corridor, Jianghan Plain, Dongting Lake Plain and Xinjiang Uygur Autonomous Region. There are 877 counties where the latter played more important role, mainly located in the Huang-Huai-Hai Plain, Loess Plateau, and the southeast of Qinghai-Tibet Plateau. In general, major grain-producing counties were big contributors to the ten-year consecutive grain output increase from 2003 to 2013. Fiscal support for major grain-producing counties was needed to keep the grain production capacity. Only in this way, the national grain security will be ensured. [ABSTRACT FROM AUTHOR]

Precise seeding on point is a wheat seeding method which can control the spatial distribution of seeds in the soil effectively and strive to achieve equal seeding amount, grain spacing and seeding depth, so as to further improve the seeding quality of wheat. In order to achieve this goal, the organic combination of precision seeding and accurate seed casting was put forward. The functions of quantitative seed separation and stable seed transportation of seeder were integrated into the seed casting device to change the form of seed transportation, so as to realize the precision fixed seeding of single grain of wheat. This paper put forward a method based on seed adsorption, point perforation and precision seeding. According to this method, the pinhole-tube wheat precision seeding device was designed. The main working principle is as follows: The outer wall of the seeding wheel is pressed on the soil, and the pinhole seed suction tube is inserted into the soil. When the seeding wheel rolls, the pinhole seed suction tube is driven to rotate. The pneumatic distribution mechanism is connected with the fan that is divided into negative pressure area and positive pressure area to provide pressure for the pinhole seed suction tube in the position of seeding and throwing. The pinhole seed suction tube with negative pressure picks up the seeds in the seed box, and transports the seeds to the soil with the rotation of the seeding wheel. When the pinhole seed suction tube reaches the designated seed drop point, it is in the positive pressure area of the pneumatic distribution mechanism. The seed suction hole changes from negative pressure to positive pressure, and seeds are blown into the soil to complete the sowing. According to the number of basic seedlings required by precision seeding method, the planting frequency was calculated to determine the plant spacing. The appropriate directional planting distance was 2.73 cm and the spacing angle in seeding wheel of pinhole seed suction tube was 15.65°. When the pinhole seed suction tube was inserted into the soil, the rotation of seeding wheel and other factors would produce displacement in the soil. The stirring distance in the soil was 7.86 cm by calculating, which was greater than the plant spacing. 3 rows should be arranged because of the less the row number of pinhole seed suction tube, the greater the absolute distance between 2 plants. The seed suction hole diameter had a great influence on seed suction effect by studying the principle of pinhole seed suction tube to absorb seed. The mechanical model of seed suction was established when seed suction holes were arranged in different positions of pinhole seed suction tube. The factors arranged from largest to smallest by the seed suction force requirement was reverse side of contact soil surface, top surface and contact soil surface. It was concluded that it would have a great influence on seed suction by analyzing the seed suction surface shape of pinhole seed suction tube. Therefore, the above 3 factors were taken as influencing factors, and the orthogonal test was conducted with the parameters of leakage seed index, multiple seed index and single seed index. The optimum combination was obtained as follows: the seed suction hole position was in the top surface, the seed suction hole diameter was 2 mm, and the seed suction surface shape was convex. Under the condition of optimal parameter combination, the experimental results showed that the leakage seed index was 4.1%, the multiple seed index was 7.3%, and the single seed index was 88.6%, which met the design requirements. By analyzing the experimental data, it was concluded that the 3 factors had significant influence on the experimental results. The reliability of the theoretical analysis results was verified by comparing with the experimental results. The rationality analysis of the differences between the results and analysis is carried out to lay a foundation for further research. It provides a reference for the design and performance improvement of precision seeding machinery and promotes the development of precise seeding on point of wheat. [ABSTRACT FROM AUTHOR]

The grain production transformation is the core content of the evolution of the rural production system. The breakthrough of grain production transformation research can clearly reflect the evolution of regional rural man-land interactions, and provide a new perspective for deepening urban- rural integration and rural transformation. Based on the analysis of grain production transformation since China's reform and opening- up, this paper attempts to construct an analytical framework for China's grain production transformation. We identified four stages in transformation process of grain production, namely, grain as the key link, gricultural restructuring, comprehensive transformation and urban-rural integration. Using GLRL model, the analytical framework of China's grain production transformation was constructed. It was found that the grain production evolved from "Green Loop" stage to "Red Loop" stage, which was gradually integrated from rural local production network into urbanrural production network. In addition, the disturbance factors driving the grain production transformation have multiple spatial-temporal features and cross-scale effects. Factors such as urban-rural integration development, rural vitalization strategy, rural man-land interactions, and globalization will have an important impact on future grain production transformation. Furthermore, optimizing the relationship between grain production and rural transformation provides guarantees for safeguarding the orderly transformation of grain production, and improving the conditions for creating the rural production system. [ABSTRACT FROM AUTHOR]

Energy feedstuffs, the most important and indispensable components in the pelleted complete feeds, provide energy in the form of soluble carbohydrate, oil and fat. Energy feedstuffs mainly includes cereals, cereal brans, molasses, oil, tuber and tuberous root, among which corn, wheat, barley, sorghum, wheat/rice bran, pelleted cassava residue and beet pulp are widely utilized in diets for livestock and poultry. Knowledge of the thermal properties of different feedstuffs is required for designing and parameter optimization of thermal process such as conditioning and pelleting processing, especially when energy costs, pellet quality and uniformity are the main consideration. The specific heat, thermal conductivity and thermal diffusivity are the most important thermal properties. In this paper, eight energy feed ingredients (4 cereal grains: corn, wheat, barley, sorghum; 4 processed by-products: wheat bran, pelleted cassava residue, pelleted beet pulp, rice bran) were obtained from a feed mill in the suburb of Beijing, and ground in a mini-mill equipped with screens having a aperture size of 1.5, 2.0 or 2.5 mm to obtain feed meals with three particle sizes (except rice bran, which could pass through the 1.5 mm screen completely without being ground). The moisture content of all feed meal samples was conditioned to 12% wet basis in order to eliminate the effect of moisture content difference on thermal properties. The specific heat, thermal conductivity of feed meals at the temperature range of 25-100 °C were determined by DSC (differential scanning calorimetry) and KD2 Pro (thermal properties analyzer), respectively. Thermal diffusivity of feed meals was calculated using measured thermal conductivity, specific heat, and bulk density. Based on the experimental data, prediction models of three thermal properties as a function of temperature were established. The effects of particle size on thermal properties of feedstuffs were analyzed. The particle size of eight feedstuffs grinding through screens with aperture size of 1.5, 2.0 and 2.5 mm ranged from 257.61 to 511.79 μm, 325.65 to 594.83 μm and 335.28 to 671.05 μm, respectively, which increased significantly with the increase in mesh size. There were significant differences between the values of particle size of 8 feedstuffs through the same mesh size. The values of specific heat of 4 grain meals (passing a screen with aperture size of 1.5 mm) increased with temperature (25-100 °C) and ranged from 1.678 to 2.421, 1.644 to 2.402, 1.642 to 2.385, and 1.649 to 2.441 kJ/(kg·K), respectively. For wheat bran, cassava residue and beet pulp, the values were found to range from 1.621 to 2.540, 1.580 to 2.195, 1.746 to 2.351 kJ/(kg·K). The specific heat of rice bran raised from 1.966 kJ/(kg·K) at 25 °C to 1.985 kJ/(kg·K) at peak temperature (28.0 °C), then declined to 1.868 kJ/(kg·K) at end-set temperature (33.5 °C), and finally increased to 2.671 kJ/(kg·K) at 100 °C. There was no significant effect of particle size on the specific heat of all feedstuffs (P>0.05). The specific heat followed linear relationships with temperature at the range of 25-100 °C for 4 grains, and cubic polynomial relationships for wheat bran, cassava residue and rice bran, and a second order polynomial relationship for beet pulp. The values of thermal conductivity of 4 grain meals (passing a 1.5 mm screen) increased nonlinearly with temperature (25-100 °C) and varied from 0.089 to 0.299, 0.078 to 0.336, 0.088 to 0.276 and 0.082 to 0.288 W/(m·K), respectively. For 4 processed by-products, the thermal conductivity was found to raise from 0.054 to 0.190, 0.092 to 0.362, 0.085 to 0.263, and 0.064 to 0.202 W/(m·K), respectively. Significant differences were observed between the thermal conductivity of 8 feed mills (passing a 1.5 mm screen) at a higher temperature (85 or 100 °C), and the thermal conductivity of cassava residue was the highest, followed by wheat, wheat bran with the lowest value. For the same feedstuffs, the thermal conductivity of feed mills, at the same temperature, decreased generally with the increase in particle size, and the higher temperature, the stronger decrease. Cubic polynomial relationships of thermal conductivity with temperature (25-100 °C) were established for 4 grains and beet pulp with different particle sizes, and quadratic polynomial relationships were obtained for wheat bran, cassava residue and rice bran. The values of thermal diffusivity of 4 grain meals (passing a 1.5 mm screen) varied from 7.459×10-8 to 17.320×10-8, 6.694×10-8 to 19.195×10-8, 7.878×10-8 to 17.045×10-8, and 6.857×10-8 to 16.109 ×10-8 m2/s at temperature range of 25-100 °C, respectively. The values was observed to ascend from 9.543×10-8 to 20.892×10-8, 8.217×10-8 to 23.254×10-8, 7.258×10-8 to 16.646×10-8 and 8.092×10-8 to 18.718 ×10-8 m2/s for 4 processed by-products, respectively. In general, the thermal diffusivity of the 8 energy feedstuffs had a slow increase with temperature at the range of 25-55 °C, and a sharply raise with temperature at the range of 55-100 °C. The thermal diffusivity of all 8 feedstuffs tended to decline with increasing particle size. The thermal diffusivity displayed second order polynomial relationship with temperature at the range of 25-100 °C for wheat bran and rice bran, and cubic polynomial relationships for the other 6 feedstuffs. [ABSTRACT FROM AUTHOR]

Silo is widely used in grain, logistics, electric power, metallurgy and other industries. Therefore, the reasonable design of silo structure is the key. China is a large country of grain production, with application of the modern granary environmental protection, energy saving, green and other concepts, the cylinder wall is higher, and larger diameter, occupies less land, saves resources of the silo and is more and more in line with the future development trend of granary, and with the trend of rapid development around the world. With the increasing height and diameter of silo, the problem of failure in silo discharging is becoming more prominent. The dynamic lateral pressure of grain silo during discharging is the major cause of silo failure. In this paper, based on the indoor grain silo discharging model test, the whole process of the silo center emptying was recorded with high-speed camera, the flow pattern of grain was analyzed with image processing technology, and the dynamic pressure generated during the discharge process was measured. Based on this test, the particle flow code (PFC3D) was used to carry out numerical simulation to track the movement of specific particles in the test. By comparing the results of the experiment and the numerical simulation, the mechanism of overpressure in the discharge of the silo was explored. Through this study, in the process of discharging in the center, there were two kinds of flow states, the mass flow and the tubular flow. At the beginning of the discharge, the stored material flowed as mass flow. After a period of time, the upper part of the material flowed as mass flow, the bottom of the storage was a tubular flow, and the mass flow was in the high diameter ratio close to 1 of the height position to convert to tubular flow. When the discharging height reached 1.1m, the stored material flowed in tubular flow until the discharge was completed. Both the dynamic lateral pressure and the static lateral pressure increased with the depth of the measuring point, and the dynamic lateral pressure was greater than the static lateral pressure. At the beginning of the discharge, the dynamic lateral pressure measured by the silo suddenly increased, and then the dynamic lateral pressure value decreased with the continuous reduction of the storage height. The overpressure coefficient measured by the three groups of sensors was larger in the height range of the high diameter ratio close to 1, and the overpressure phenomenon was obvious. In the process of silo discharging, the speed of tubular flow of the bottom stored material was greater than the speed of the mass flow of the middle and upper stored material. There was a pressure arch at the junction of the two flow states, and the existence of the pressurized arch hindered the normal flow of the upper stored material, which led to the self-weight of the stored material and the additional force caused by the change of momentum was almost entirely by the arch, resulting in the increase of the dynamic lateral pressure and a significant overpressure phenomenon. [ABSTRACT FROM AUTHOR]

Agricultural land consolidation is one of the largest human activities in China with lots of impacts on ecological environment. Ecosystem services are the basis for human survival and development. It is of great significance to explore the impacts of agricultural land consolidation on regional ecosystem services. This study would promote the balance, efficiency and stability of the ecosystem services in the agricultural land consolidation area. This research took Jianxi River Basin which in Fujian province as case study area. The data used in this paper were remote sensing data, the agricultural land consolidation project data, land use data, soil type map and so on. Carbon storage ecosystem services in the Jianxi River Basin were estimated by using the multi-source model of carbon storage. And crop production ecosystem services in the Jianxi River Basin were estimated by using the potential productivity model of cultivated land. Based on the comparative analysis, the effects of agricultural land consolidation on two ecosystem services were studied. The research showed that compared with 2010, total carbon storage decreased by 38.28×106t in 2016. The total carbon storage in 2016 was 369.29×106 t. The area of agricultural land consolidation project accounted for 1.41% of the area of the Jianxi River Basin. And the project area contributed 1.70% to the decrease in carbon storage. This indicated that agricultural land consolidation has negative effects on carbon storage services in the ecosystem of Jianxi River Basin. The carbon effect produced by agricultural land consolidation should not be neglected. Compared with 2010, the total crop production service in Jianxi River Basin increased by 10.83×104t in 2016, reached to 124.46 ×104t. The area of agricultural land consolidation project accounted for 14.61% of cultivated land area of the Jianxi River Basin. And the project area contributed 20.87% to the increase in crop output. This indicated that agricultural land consolidation has effectively improved the crop production services of cultivated land in the Jianxi River Basin. It is necessary to pay attention to the application of ecological measures in agricultural land consolidation. According to the research results that carbon storage services will be reduced by agricultural land consolidation, and three suggestions are put forward. 1) If the agricultural land consolidation measures would do great damage to the cultivated soil, measures such as topsoil stripping and backfill and guest soil should be adopted to protect the carbon sequestration capacity of the soil. Planting green manure and returning straw to field is also an effective biological measure to increase soil carbon sequestration. 2) Attention should be paid to the construction of ecotype ditches and field roads, and new environment friendly materials such as environment friendly field sand stone pavement additive, soft slope protection material, heavy metal passivating agent, water retaining and fertilizer agent and so on are used to reduce the loss of organic carbon storage caused by pavement hardening and excessive coagulation. 3) Strengthen the management and protection of agricultural land consolidation. Intercropping rotation system and farm manure should be used to increase the carbon storage of cultivated land through later management and protection. [ABSTRACT FROM AUTHOR]

The environmental effect of grain production never fails to attract high attention of researchers and policy makers, especially in the main grain production area in China. The grey water footprint (GWF), as an indicator of aquatic pollution, is defined as the volume of freshwater required to assimilate the load of pollutants based on existing ambient water quality standards. The theories and methods of the GWF provide a new sight to evaluate environmental effects of grain production on water pollution level. By using the statistics methods, this study presented the past and the future changes of GWFs related to total nitrogen (TN), total phosphorus (TP) and pesticide inputs of grain production at the regional scale. Evaluation method of environmental sustainability of grain production for the ambient water quality under annual average discharge scenario was proposed using regional water environment pressure (WEP) and the discrete grey model DGM(1, 1). To test the approach, The Dongting Lake area was chosen as the case study area. As the main grain production area in China, high inputs of nitrogen fertilizer, phosphate fertilizer and pesticide have been broadly adopted to increase grain yield in this area, and caused serious agricultural non-point source pollution which has been recognized as a major contributor to water quality degradation. In this area excessive nitrogen and phosphorus have become important risk factors. The GWFs of the grain production showed a large variation among different counties from 1994 to 2012. Regional annual average GWF of grain production industry was 1.19-23.61 x 108 m³ at the county level, and the minimum and maximum GWF occurred in Xiangtan City and Xiangtan County, respectively. The GWF of grain production was 1.06-5.58 m³/kg in the period from 1994 to 2012. The counties which had medium value of the GWF were mostly located around the Dongting Lake. The annual total grey water volume for grain production industry was 273.00-438.08 x 108 m³ from 1994 to 2012, and the average value was 347.65 x 108 m³. The GWF trends of grain production industry were declined first, and then increased during 1994-2012. For analyzing the future trends, 2015 and 2020 were selected as the predicted years. The results showed that the grain production industry's GWFs were 431.16 x 108 and 498.54 x 108 m³, respectively, in 2015 and 2020. We illustrated spatial trends for WEP in 2015 and 2020 under annual average discharge scenario. Compared with the period from 1994 to 2012, the value of WEP of grain production industry increased from 0.60 to 0.76 in 2015 (the ratio that evaluation units whose water quality deteriorated accounted for the total units increased to 37.14%) and 0.87 in 2020 (increased to 42.86%). Although the WEPs in some counties were over 1 during 1994-2012, the evaluation results suggested that the level of WEP will show an increase trend in the future, which meant the negative environmental effect of grain production would increase continuously. From the spatial aspect, the counties with high WEPs were distributed near the Dongting Lake, for TN or TP. The results indicated that many counties' water resources would be polluted by TN or TP in the future. In addition, the TP has become a major type of agricultural non-point source pollution in the Dongting Lake area. Overall, the GWF as a useful indicator for water environmental quality assessment has been proved, and the managers are facing great challenges of environmental sustainability of grain production. However, the GWF also needs to be further discussed. For example, the calculation model of the GWF should take the effects of water quality, water quantity and time into consideration to assess environmental effects more accurately. In conclusion, the method in the paper can be employed as a novel approach to evaluate environmental effects of grain production on water pollution level. This paper provides a reference for other regions to assess the environmental risk of grain production, and the results also provide good suggests for sustainable agricultural planning and agricultural policy making. [ABSTRACT FROM AUTHOR]

Corn production occupies an extremely important strategic position in grain production and grain security. Seeds are the most basic means of production in crop production, and the quality of seeds directly affects the subsequent crop cultivation, harvest yield and quality of grain. Moreover, directional seeding of corn can effectively improve the yield of corn, and it is necessary to select seeds before planting. Certainly, to choose good corn ears for threshing can get better corn seeds, which can lighten the workload of subsequent seeds selection and also improve efficiency. So, this study designed the scheme of corn ears selection device based on machine vision, and developed the selection algorithm for corn ears on the dynamic assembly line, which could complete the detection of the corn ears. First, the binary image of the corn ear to be detected was gained according to Otsu method, and after tracking the whole corn ear's contour, the length ratio between the long axis and short axis of the corn ear's contour was calculated. Then, by using the formula, R plus G minus B times 2, the area with yellow characteristics was strengthened and was even extracted after histogram threshold segmentation, and so the plumpness of the corn ear was detected by calculating the ratio of the extracted area and the whole area of the corn ear. Further, based on the characteristics of X cumulative distribution diagram, the middle ear row was extracted by tracking the seams' edge between ear rows. Also, based on the characteristics of ear row's Y cumulative distribution diagram, every seed in the middle ear row was extracted by using the method of threshold segmentation, and then the length-width ratio of their end-face was calculated by tracking their contour. And the flatness of the seeds was acquired. For the corn ears' video file acquired on the dynamic assembly line, only when the vertical coordinate of corn ear's center is located in image's central region, do the relevant frame image is tested. According to the characteristic parameter, the length ratio between the long axis and short axis of corn ears, the small corn ears were eliminated. The plumpness of corn ears, the corn ears which were mildewed or seriously lacked seeds were eliminated by the characteristic parameter, and, the flatness of corn ears, the corn ears in which the end-face of corn seeds were mostly round were eliminated by those parameters. This corn ears selection algorithm can rapidly and accurately detect the various characteristic parameters of corn ears, and finally determines their eligibility. In the experiment, 50 random samples of corn ears were detected, and the results showed that the determination accuracy of dynamic location was 100%, the recognition accuracy of identical corn ears was 100%, the detection accuracy of morphological characteristics was 100%, the detection accuracy of corn ears' plumpness (on the other hand, the degree of seed lack or mildew) was 96%, the detection accuracy of rectangular degree of seeds' end-face in corn ears is 98%, and the overall detection accuracy was 94%. This paper provides reference for the research on corn ears selection as well as corn seeds selection which is served for directional seeding. This paper provides reference for the research on corn ears selection early in corn seeds selection which is served for directional seeding. [ABSTRACT FROM AUTHOR]

Grain drying operation is an important part of food safe storage. In recent years, many scholars and engineers have done a lot of work on grain drying technology aiming to reduce energy consumption and realize automatic control of drying devices, but online moisture accurate detection in the grain drying that is core technique is still application difficulty to be solved, which restricts the development of grain drying system. Based on the analysis of the advantages and disadvantages of the technical principle of current online grain moisture meters, this paper presented a continuous single grain online moisture meter based on the water detection principle of resistance method. Physical dimensions of main varieties in main paddy, wheat and barley producing areas in China were measured, statistics of grain equivalent diameter were made, and pitch diameter and helix angle of stainless-steel incongruous sine screw rod were calculated by applying static sliding friction angle between single grain and metal surface. Therefore, the grain sampling device of moisture tester was designed, which was composed of a double-screw rod and a split grain knife. The grain sampling device screened out sundries and excess grain, and ensured single grain and continuity at the same time when sampling. According to the results of the experiment and simulation, 3 kinds of knurling forms with 0.4 mm modulus were chosen, including straight lines, oblique lines and net-mesh lines, and net-mesh lines had the optimal rolling smoothness among them, followed by straight lines knurling and oblique lines knurling. Considering the removal effect of adhesion on roller, the brushing effect of oblique lines knurling was the best, so the roller surface chose oblique lines form. Yangjing 239, Huaimai 33, and Yangnongpi 4 were chosen respectively as the test samples of paddy, wheat and barley, prepared as multiple samples with different moisture content. Meanwhile, when 105 ℃ drying method was adopted to test moisture content of each sample in the laboratory, the direct-current (DC) resistance of single grain with different moisture content compacted by the roller was measured by using universal electronic testing machine, programmable DC power supply with high precision, digital multimeter and other equipment; the steady resistance value was taken when the distance between the 2 rollers was 0.4 mm, and average resistance value was obtained after testing 100 samples for the samples with the same moisture content. Regression curves between the grain moisture content and single grain resistance of paddy, wheat and barley were built according to the experimental data. The calculation function expression of grain moisture content was obtained through polynomial regression on curve. Multiplex proportional circuit was designed, providing possibility to solve precise detection of extremely wide resistance of specific volume ranging from 10-2 to 1010 Ω·cm. Second order voltage-controlled active low-pass filter based on four-channel amplifier AD8643, and 50 Hz band-stop filter circuit consisting of operational amplifier LM358 were designed to meet the electromagnetic compatibility requirements for on-line grain moisture tester detection. Hardware and software platforms of ARM CortexTM-M3 core’s low power 32-bit microprocessor STM32L151CBQ6 were applied to finish both the sampling of grain moisture and the design of processing program. Online detection comparison tests on site showed that, when the drying temperature ranged from -5 to 55 ℃ and the moisture content ranged from 10% to 35% for paddy, wheat and barley, the online moisture measurement accuracy of the tester was less than ±0.5%, which satisfied online moisture detection requirements for the drying of the 3 kinds of grains. The design method can provide a reference for the online detection of water in the drying process of grain. [ABSTRACT FROM AUTHOR]

Crop yield information is the precondition for the implementation of precision agriculture, and it is the key to organize farmland production and achieve decision-making for agricultural management. Aiming at collecting yield data by the grain yield measurement and control system in harvest field and transmitting the collected data to the yield server in real time, and meanwhile meeting the demands of data access to all kinds of terminals, a data collection and service platform for monitoring grain yield was developed. It is helpful to achieve data real-time interacting among the on-site yield monitoring system, the mobile terminals and the remote yield server. Socket and SOAP (simple object access protocol) technologies are used to implement data exchanging between the remote server and various heterogeneous platforms. A grain yield data collecting system was developed and embedded in the IPC (industrial personal computer) mounted on the combine harvester to collect yield data in real time, and its modules included device setting, data collecting, data parsing and data uploading. The yield data are composed of the information input by user (farm and plot identification, which are input once for each plot), the global position system (GPS) data (longitude, latitude, altitude and time), the data (harvester speed, harvester cutter width, impulse voltage, grain moisture and grain temperature) from the sensors mounted in the harvester and the CAN (controller area network) bus. The collected yield data are packaged every 1 second and transferred to the yield server through Socket via GPRS (general packet radio service), and then they are parsed according to the yield data exchanging protocol and stored into the yield database established in the server. Then the yield data can be calculated, processed and visualized according to various modules embedded in the yield data collection and service system which is developed using Hadoop and Web GIS (web geographic information system) technologies. And the modules include user management, news management, bulletin management, document management, farm management, plot management, yield data management, harvester tracing and Web GIS service, and the grain yield data collecting system is connected with the remote data access terminals through the data collection module and data service module which are embedded in the yield data management. Yield data service is implemented using Web Service based on SOAP for data sharing for various terminals (such as mobile, tablet PC (personal computer), PDA (personal digital assistant), and desktop) with different operating systems (such as Windows, Macintosh, Linux or Android). A grain yield querying system was established for testing the yield data service XML (extensive makeup language) interface provided by the yield data collection and service system, the information including farm, plot and yield could be accessed smoothly, and the yield data visualization could be achieved accordingly. For improving the yield data transmission efficiency, GZIP (GNUzip) is used to compress SOAP messages and reduce bandwidth consumption. In addition, the digital signatures and encryption technology are used to guarantee the security of data transmission via internet. The system experiments were carried out, and the results showed that the grain yield data collecting system worked well on-site and the yield data could be collected and uploaded every 1 minute; the data collection and service system could receive, calculate, process and visualize the real-time yield data efficiently; and the Web Service interface could push the yield data querying results quickly according to client requests. The study indicates that the yield data interaction and sharing between heterogeneous platforms can be achieved by using the yield data collection and service platform proposed in this paper. [ABSTRACT FROM AUTHOR]

Maize planting in northern region of China plays a vital role in the crop production in China, and it occupies a large proportion in total grain production and planting area in China. Meanwhile, northern region of China is prone to drought and the drought normalization happens in this area seriously, which restricts the steady development of maize. The data used in this paper included daily weather data of 217 meteorological stations in the 14 provinces (municipalities, or autonomous regions) in northern region of China from 1961 to 2010 and crop, soil, field management data of spring maize. Based on the total precipitation during the growing season of spring maize we divided the study area into 6 precipitation zones (I -VI) with the interval of 100 mm, and then analyzed the effects of drought of different grades occurring in main growing stage on grain yield of spring maize in northern region of China by using the crop water deficit index as the agricultural drought index and the agriculture production systems simulator (APSIM) as the research method. The results showed that the yield reduction of spring maize caused by drought in northern region of China had a decreasing trend from west to east, and the precipitation distribution led to the differences of damage degree in each area directly. The precipitation during growing season of spring maize in Zone I located in western region (including Xinjiang, western Inner Mongolia and northern Gansu) was below 100 mm, and the natural precipitation couldn't meet the need of growth and development of spring maize, so the drought risk of planting spring maize under rainfed conditions in western oasis irrigated agricultural area was great, and it needed to energetically develop water-efficient irrigation in this area. While the precipitation during growing season of spring maize in Zone VI located in southeastern region (including Southern Jilin, eastern Liaoning, southern Henan and southern Shaanxi) was above 500 mm, and the natural precipitation could meet the requirements of spring maize growth and development basically, so production in eastern rainfed agricultural area would be less affected by drought, and it was difficult to reflect the influence of drought grade difference on production accurately. In addition, the ratio of the station with yield reduction had a decreasing trend with the increasing of yield loss degree; from jointing to tasselling stage, the yield reduction in northern region of China was between 0 and 50%, and there were 37.3% of stations with the yield reduction of between 0 and 10%, and only 4.1% of stations with the yield reduction of between 40% and 50%. Drought happening from jointing to tasselling stage of spring maize will cause serious influence on grain yield, and the yield reduction in this stage is higher than that from tasselling to maturity stage. Besides, the discrete degree of yield reduction in this stage is also higher than that from tasselling to maturity stage. The influence degree of drought of each grade on crop production is different; from jointing to tasselling stage, the interquartile ranges of yield reduction caused by drought are extreme drought (20.1%-33.6%), severe drought (12.0%- 20.3%), moderate drought (6.3%-15.2%) and light drought (4.7%-11.6%), respectively. [ABSTRACT FROM AUTHOR]

There is an important significance for China's food security to explore the fluctuation characteristics and influence factors of grain output per sown area (hereinafter referred to as grain yield), and then to take corresponding measures to stabilize and improve the grain yield level. In this paper, the time-series yields of grain and main crops (rice, wheat and maize) from 1978 to 2012 in China were decomposed using empirical mode decomposition (EMD) method, and then multi-scale fluctuation characteristics and its main influence factors of grain yield were analyzed. The results showed: 1) the time series of grain yield could be decomposed into two intrinsic mode functions (IMF) and a residual item. The residual item denotes a slow and steady rising trend in grain yield which is dominated by the technological progress. The IMF1 and IMF2 represent a short-term fluctuation in about 4-yr cycle and a medium-term fluctuation in about 9-yr cycle, which respectively reflect the influence of meteorological and policy factors on grain yields according to the analysis of grain production system. The variance contribution rate of the residual item was greatly larger than that of the IMFs, which means the upward trend in grain yield was more pronounced than fluctuations. 2) Fluctuation of trend yield of grain was distinct before and after 1997: fast rise with an average annual growth rate of 2.28% before 1997 and slow rise with an average annual growth rate of only 0.69% after 1997. The change of trend yield was similar between rice and grain, but the former seemed to rise more slowly after 1997. For wheat and maize, the trend yield was still increased obviously although the growing rate had been significantly slowing down after 1997. 3) The IMF2 included 3 complete cycles (1979-1988, 1989-1993, and 1994-2002) and an ongoing cycle (2003 to present) which coincided with adjustment of Chinese agricultural policy. In general, the impact of policy and market factors on fluctuation of grain yield is greater than that of climate factors, but responses of different crops to different policies varied: policies on land, tax, subsidies, incentives and insurance had positive or negative effect on medium-term fluctuation of main crops synchronously, but price policies was not the case for main crops especially for maize. Medium-term fluctuation rate of grain yield was 2.94%, and that of wheat was 3.83%, significantly higher than that of maize (2.38%) and rice (2.18%). It suggested wheat's vulnerability to policies. 4) The short-term fluctuation rate of grain yield was 1.80%, and that of maize, wheat, and rice was 3.38%, 2.55%, and 1.06%, respectively. It indicated that Chinese grain production system had a strong ability to resist against meteorological disaster. The disaster prevention capabilities of different crops was not the same, and maize was more easily affected by meteorological disasters than wheat and rice. 5) Both considering the short-term and medium-term fluctuation rates, rice was the most stable crop in yield. The main problem of rice production was the slow growth of yield trend after 1998, while maize was strongly influenced by meteorological disaster, and fluctuation of wheat was significantly affected by policy cycles. At present, China's agriculture production has entered a new development stage. It is necessary to adjust the agricultural policy in order to adapt to the new situation. The results here can help with decision-making and adjustment of agricultural policies. [ABSTRACT FROM AUTHOR]

Grain storage has very important effects on national security and has been given increasing attentions at past several decades. Condensation is one of the main dangers to the grain storage safety. Temperature, moisture and warehouse type are the three most important factors to form condensation. However, it is very difficult to study the effects of temperature and moisture on the grain storage safety in the actual granary due to the huge cost. So, it is a good choice by building models to forecast the changes of temperature or humidity in the granary by experiments. At present, the studies were still at the middle-small experimental stages in the domestic and overseas. Due to the differences of climate, long storage period and warehouse types at different regions, it is more difficult to build the universal temperature or humidity models in China than other nations. To explore the condensation processes, wheat were storage in steel squat silo and horizontal bin located in Tianjin District respectively, which were used widely to store grain in China. The changes of temperature and water vapor pressure of the wheat in spring, summer and winter were researched in the paper. The grain temperature data in different seasons was obtained by sensors array. Second Newton interpolation method was used to obtain the fitting algorithm of temperature. The data of wheat water vapor pressure was figured out by WU model. The temperature fields and the water vapor pressure field of the wheat in two researched storehouse were reproduced by MATLAB software, respectively. Then, the cloud maps were analyzed according to the coupling principle of temperature and water vapor pressure fields and WU model. The results showed that a large cold area existed in the wheat in the steel squat silo or the horizontal bin in summer, which could be the main reason of non-dewfall and resulted in a storage safety. A multi-level water vapor pressure zone, which was defined as the low-water vapor pressure area and high-ones alternately appeared in the stored wheat, all was observed in the wheat in the steel squat silo and the horizontal bin during late winter to early spring. More significant multi-level water vapor pressure zone (which suggested a larger gradient of grain temperature and water vapor pressure) and more moisture absorbed rate of the surface grain than that of the horizontal bin resulted in the condensation on the surface occurred more easily in the steel squat silo in early spring, which suggested a storage risk of the wheat in spring. The isotherm was different remarkably between the two warehouses. In the steel squat silo, the isotherm was closed, but it presented non-closed in the horizontal bin. Based on the change direction of isothermal curve, it could deduce that there was another horizontal bin bordered. Additionally, the isotherms of the two horizontal bins could close well from the temperature field cloud maps, which suggested grain stored in the bordered horizontal bin. The results were in consistent with the actual. They provided not only new thought of forecasting condensation, but also new perspective of making inventories of warehouses. [ABSTRACT FROM AUTHOR]

In this paper, taken ‘Gangyou725' as a control, the field experiments were conducted to study the effects of different combination of plant density, N rate and N application pattern on grain yield and rice quality of high-quality hybrid rice ‘Yixiang4245'. The results showed that the grain yield and rice quality of hybrid mid-season rice was not significantly affected by N application patterns. The chalky grain rate, chalkiness and amylase of ‘Yixiang4245' were significantly lower than that of ‘Gangyou725', while the differences between 'Yixiang4245' and ‘Gangyou725' in grain yield, brown rice percentage, milled rice percentage and head rice percentage were relatively small, and the gel consistency of ‘Yixiang4245' was significantly higher than that of ‘Gangyou725'. Significant differences of grain yields of ‘Yixiang4245' were observed among different combinations of plant densities and N application rates，of which the highest yield of ‘Yixiang4245' was observed in combination of mid-density and mid-N rate, with average of 7. 96 t・hm-2, 5.2% higher than that of combination of high-density and low-N rate and 6.9% than that of combination of low-density and high-N rate. The rice quality of ‘Yixiang4245' was not significantly affected by combinations of plant density and N rate. In a word, it was concluded that increasing grain yield and rice quality of ‘Yixiang4245' could be achieved under the combination of mid-density and mid-N rate. [ABSTRACT FROM AUTHOR]