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Meat goose can represent one of the most significant economic waterfowl in China. An excessively high stocking density can reduce the production performance and welfare of geese. Moreover, the light-emitting diode (LED) green light can play a pivotal role in regulating the growth and development of embryos and offspring in chickens. This study aims to determine the optimal regimen of LED green light in the high-density rearing mode of goslings. According to the actual production, a two-factor experiment was designed with the incubation light (dark and LED green) and growth light (LED white and LED green). A systematic analysis was made to explore the effects of LED green light on growth performance, intestinal development, blood hormones, feather quality, and pecking behaviors of geese in high-stocking density. The results show that the light intensities were 30–40 and 30–35 lx during the incubation and brooding period, respectively, with a light cycle of L:D = 24:0. The growth performance of geese was significantly improved by LED green light during the gosling brooding period. The LED green light during the growing period was found to significantly increase the body weight of geese at 14 days, as well as the daily gain and feed intake of geese for 1 to 14 days (P < 0.05). Furthermore, there was a significant decrease in the ratio of feed to gain of geese for 1 to 14 days (P < 0.05). A significant reduction was found in the concentration of serotonin and corticosterone in the blood, as well as the duodenal crypt depth of the geese at 14 days in the green light group during the growth period (P < 0.05), compared with the white light group. Furthermore, the LED green light irradiation during the growing period was observed to significantly increase the length of the chest and abdomen feathers of geese at 14 days post-hatching (P < 0.05), whereas, the back bare score of geese was reduced at 14 days post-hatching (P < 0.01), and the average pecking time and frequency of geese was reduced for 1 to 14 days post-hatching (P < 0.001). Thus, the green light environment during the growing period was significantly beneficial to the quality of the feathers and the development of geese plumage. The LED green light during the embryonic period was found to significantly reduce the average pecking time and frequency (P < 0.05) for better feather pecking behavior in geese. Moreover, the hatching procedure of green light outstandingly reduced the duodenal crypt depth (P < 0.01), where there was an increase in the jejunal villus height of geese at 14 days (P < 0.05), compared with the control group. The adverse effects of intensive farming were reduced on the intestinal development of geese. Moreover, there was no significant interaction to identify between the incubation and brood lights, in terms of the regulation of growth performance, intestinal development, blood hormones, feather quality (feather length, cleanliness, and damage degree), and feather pecking behavior of geese. Therefore, the LED green light shared the positive regulations on the negative effects of high-density rearing of goslings. Moreover, the LED green light during the growing period of goslings yielded superior outcomes. It is thus recommended that green light irradiation can be employed at the brood stage of goslings in actual production, in order to mitigate the adverse effects of modern intensive farming on goslings. The findings can provide a theoretical basis for the efficient production of geese. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Irrigation & Drainage is the property of Journal of Irrigation & Drainage Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

To achieve energy conservation, emission reduction, and sustainable development in aquaculture, characterized by low carbon efficiency, it is essential to address the issue of freshwater pond aquaculture tailwater treatment. This paper summarizes the treatment methods and technical characteristics of freshwater pond aquaculture tailwater both domestically and internationally according to the characteristics of pollutants in typical pond aquaculture tailwater; compares the typical pond culture tailwater treatment modes such as “three ponds and two dams” “container + ecological pond” “ecological wetland”, etc.. The physical purification technologies such as vertical flow sedimentation, cyclone separation, filtration screen, air flotation, etc., and the chemical and biological purification technologies such as ozone-micro-nano flotation, flocculation, microbial preparation, activated sludge, new biofilm reactor filtration, aquatic plant etc., were discussed. The hot research directions and key technical problems in this field were pointed out, including the development of "energy-saving, emission reduction, ecological and efficient" intensive pond farming mode, the research and development of special treatment equipment for aquaculture wastewater, and the improvement of purification efficiency and floor space, etc., which can offer theoretical guidance for the development of integrated and rapid pond aquaculture wastewater treatment technologies and equipment. [ABSTRACT FROM AUTHOR]

The decline in agricultural biodiversity and the imbalance and degradation of ecological functions within farmland systems triggered by agricultural intensification pose significant threats to the green, high-quality, and sustainable development of agriculture. Addressing the challenges inherent in intensified farmland systems has become a focal point of research both domestically and internationally, and is pivotal for the timely realization of agricultural modernization in China. This article analyzes the current status and existing issues of biodiversity conservation in intensive farmland from three aspects：the weakening of ecological functions in intensive farmland systems, the maintenance of biodiversity for farmland ecosystem functions, and the lack of awareness in biodiversity conservation in intensive farmland, based on the tasks of agricultural modernization in China and the development trends of agricultural ecological science and technology. Four action recommendations are proposed to address the current unsustainable issues in intensified farmland systems. We aim to contribute insights and recommendations for shaping a new paradigm of intensified ecological farmland construction with Chinese characteristics in the new stage, offering China ′s wisdom and solutions based on the conservation of agricultural biodiversity for sustainable green development in intensified agriculture to the world. [ABSTRACT FROM AUTHOR]

Vegetation is a key component of the complex coupled human- nature system, and there is a prominent greening trend in the Yellow River basin (YRB). We used the NOAA Climate Data Record ( CDR) of AVHRR Normalized Difference Vegetation Index (NDVI) daily dataset from 1982 to 2020 and applied a land surface phenology method to investigate the differentiation of the human- nature relationship in the YRB from a vegetation perspective. To extract vegetation intra- annual indices, we applied a land surface phenology method that integrates the SavitzkyGolay filter and double logistic fitting, in addition to the traditional annual vegetation index based on annual NDVI series. We analyzed the trend of the inter- annual and intra- annual vegetation indices and summarized the typical types of vegetation changes using k-means clustering. We also conducted an analysis of the driving factors behind the different vegetation changes. Our results demonstrated that the integrated intra- annual indices extraction method is suitable for various vegetation types in the YRB, achieving a high recognition rate of 98% . The spatial and temporal variations in the extracted intra-annual indices revealed differences in ecological engineering and agricultural activities under distinct climatic conditions. We identified five types of ecological engineering- dominated vegetation changes and two types of agricultural- dominated vegetation changes, and found that the significance of agricultural vegetation changes was comparable to that of ecological engineering. Agricultural intensification is a critical factor that cannot be ignored in vegetation research of the YRB. Given the tense relationship between humans and nature, and the severe water-food- ecological contradictions in the YRB, it is crucial to optimize agricultural water use and ensure food security. [ABSTRACT FROM AUTHOR]

Copyright of Agricultural Outlook (1673-3908) is the property of Institute of Agricultural Information, Chinese Academy of Agricultural Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The study was to improve the supply chain management level of feed enterprises and promote the modernization of feed industry supply chain. Based on the perspective of Chinese modernization, based on three transformation directions of feed enterprise supply chain management technology digitization, planning intensification and organization coordination, the supply chain management mode of feed enterprise was constructed from the aspects of demand management, relationship management, order management and service feedback management, and the specific implementation path was put forward. The results showed that the constructed supply chain management mode features data collaboration, precise management and emphasis on experience, which was helpful to optimize the management system of feed enterprises and improve the overall operation efficiency of the supply chain. The research shows that the supply chain management model of feed enterprises has management flexibility, which has a certain value of promotion and practice. [ABSTRACT FROM AUTHOR]

In order to study the influence of different coverings on wind velocity distribution in forest and windbreak effect, we examined 4 shelterbelt models which were different covering models. These models were used for a wind tunnel simulation under wind speed to evaluate the effects of coverings on the wind field and the protective effects of the shelterbelt. The results showed that within the height range of shelterbelt in the forest network, the coverings had a significant impact on the wind speed field before and after the forest belt, especially for the tall fruit crops. Under the wind speed of 8 m·s-1 the order of the average wind speed in each model forest network was Walnut + wheat mode < Apple + wheat mode < jujube + wheat mode < pure wheat mode < CK. The analysis of average control efficiency at 1 cm and 2 cm height in forest net showed that the windbreak efficiency of three fruit tree models was the best. Although the control effect of pure wheat model was weaker than that of fruit tree model, it still had a certain control effect. The results showed that the windbreak efficiency of the forest belt was significantly enhanced by the mulch in the forest net, especially the fruit crops. Therefore, with the advance of intensification and precision of agriculture, we should consider the wind proof effect of the crops especially a tall crops in the forest network when the shelterbelt is set. In order to improve economic benefits, the size of forest network should be adjusted properly and the structure of forest belt should be allocated reasonably. [ABSTRACT FROM AUTHOR]

Pig posture recognition can greatly contribute to the early warning of pig health under the complex scenes in swine farms, even to reduce economic loss. However, it is still challenging in posture recognition, due to the mutual occlusion and adhesion of group-housed pigs in the group house. In this study, a two-stage group-housed pigs pose recognition was proposed using the combination of Instance Segmentation and Classification identification. Firstly, the instance segmentation data set was used as the input, Cascade Mask R-CNN was used as the reference network, and the HrNetV2 network was as the feature extraction network of Cascade Mask R-CNN. High-precision segmentation was carried out on the pig images in different scenes. The multi-resolution image processing in the HrNetV2 was realized to reduce the loss of spatial details of the images, in order to improve the representation of the segmentation target by the model. The FPN module was also introduced to construct the HrNetV2+FPN composite structure. The pig bodies of different sizes were mapped to the feature maps of different levels, and then to achieve the effective fusion of features of different scales. The overlapping and adhesion between pig bodies were reduced for the subsequent recognition of pig body posture. Secondly, the CA coordinate attention mechanism was introduced to design the CA-MobilenetV3 lightweight pig body pose recognition network. The pig individual pose was extracted to build the data set after the segmentation. The interference of the background region was reduced to enhance the feature learning in the key parts of the pig body. CAM visualization was used to display the extracted part of the pig body pose feature, in order to realize the accurate and rapid recognition of individual pig posture. Finally, the improved model was effectively segmented and detected the pig body, indicating the more accurate segmentation edge of the pig body. There was a rough segmentation of the conventional MS R-CNN and Mask R-CNN. By contrast, the improved Cascade Mask R-CNN model was achieved 96.9%, 96.3%, 85.2%, and 89.4% for the AP0.50, AP0.75, AP0.50:0.95, and AP0.50:0.95-large, respectively. Therefore, the improved model performed better than the Mask R-CNN and MS R-CNN networks, in terms of detection and segmentation. In terms of pig posture recognition, the recall and F1 value of the CA-MobileNetV3 model increased by 10.8%, 13.1%, respectively, compared with the rest. Furthermore, the performance of the CA-MobileNetV3 network was significantly improved to identify the sitting and lying posture class. All evaluation indexes achieved an accuracy rate of 96.5%, 99.3%, 98.5%, and 98.7%, respectively, in the kneeling, standing, lying, and sitting posture class. The performance was much better than the MobileNetV3, ResNet50, DenseNet121, and VGG16 networks of the same type. In conclusion, the improved model was superior to the current popular networks, in the aspects of pig individual segmentation and pig pose recognition. The non-contact and low-cost recognition can be expected to realize the pig attitude under different scenarios, such as deep separation, mutual adhesion, and debris shielding. The finding can also provide the model support for the practical management of pig-intensive farming. [ABSTRACT FROM AUTHOR]

Black soil can be one of the most fertile soil groups with relatively high carbon stocks and production capacity. The black soil region can also play an important role in national food security and sustainable development in China. However, overexploitation and utilization have caused serious soil erosion in the black soil region of northeast China in recent years. There is a direct impact of the difference in tillage pattern on the soil erosion characteristics of sloping farmland. Fortunately, ridge farming can be commonly used in the tillage pattern. Furthermore, the ridge-furrow intervals with less amount of soil movement can also be used without occupying the farmland in this region. Therefore, it is of great significance to accurately evaluate the suitable measures of soil and water conservation. In this study, a systematic review was proposed to clarify the effects of ridge direction, ridge size, and ridge-furrow intervals on the soil erosion characteristics of sloping farmland in the Chinese black soil region. Furthermore, the relationship among the ridge patterns, the ridge-furrow intervals, and soil erosion was then established to determine the key fields to be strengthened in future studies for the major challenges. The results indicated that the pattern of longitudinal ridge-tillage was still the most common-used tillage pattern. The soil erosion gradually deteriorated to shift the soil erosion types from sheet to rill erosion, leading to less soil quality and crop yield. A better way was found to control soil erosion in the general patterns of contour ridge-tillage and sloping ridge-tillage, which was closely related to ridge failure. Among them, the pattern of sloping ridge-tillage was more likely to occur the ridge failure. Once the ridge failure occurred, the soil erosion increased significantly, even much more than that of the pattern of contour ridge-tillage. Thus, the pattern of contour ridge-tillage can be expected to effectively decrease the soil erosion at the sloping farmland in the black soil region. Furthermore, the pattern of the narrow ridge is also commonly used in the black soil region of northeast China in the long term. Therefore, it is very necessary to determine the effects of narrow ridges and their operation patterns on soil erosion. The pattern of the wide ridge is widely used in large-scale intensive farms and rural cooperatives, rather than individual farms, due to the outstanding control effect on the soil erosion for the high crop yield. Thus, it is a high demand for wide ridges among the individual farms in the future, in order to protect the precious black soil resources. The control effect of the ridge-furrow intervals pattern on the soil erosion depended mainly on the rainfall amount, rainfall intensity, slope gradient, ridge size, and the spacing of the ridge-furrow intervals. Therefore, it is suggested that the pattern of ridge-furrow intervals is gradually applied to the sloping farmland in the black soil region, in order to separate the layout, and then cooperate with the wide ridge, slope terrace, plant hedge, subsoiling, and straw return. The optimal allocation mode can be further improved the better measures of the composite soil and water conservation for less soil erosion. Much effort was also made into the effects of tillage patterns on the soil erosion of sloping farmland in the black soil region. Nevertheless, the technical conditions can still be limited to systematic research in this field. As such, the future directions can be proposed to analyze the influencing mechanism of ridge patterns, the coupling relationship between ridge direction and ridge size, the ridge design for the pattern of ridge-furrow intervals, and the comprehensive factors analysis of the effect of ridge pattern on the soil erosion in the sloping farmland. In conclusion, the systematic research is very necessary to focus on the effects of ridge patterns and ridge-furrow intervals on soil erosion at the sloping farmland in the black soil region. [ABSTRACT FROM AUTHOR]

Apples are produced in the large quantities each year, particularly for as the largest economic fruit in China. It is highly required for the rapid picking within the harvesting period. Therefore, the automatic apple picking is essential to the apple harvesting in intensive farming. An accurate and rapid identification of fruit can be fundamental for the automatic picking. However, some environmental factors surrounding the fruit can pose a great interference in the fruit identification under the natural, complex, and variable backgrounds, such as the light intensity, occlusion, and overlap of the fruit. In this study, an apple recognition was proposed using two-level segmentation and region-marked Hough transform. Experimental results show that the robust and practical performance was achieved for the apple recognition under different illumination, branch and leaf occlusion, as well as the fruit overlap. Specific steps were as follows. Firstly, the front camera (NikonD90) of the information acquisition robot was used to capture from 600-800 mm away from the fruit tree under the conditions of nature natural light and backlight, respectively. The brightness adaptive correction algorithm was then used to correct the brightness of apple images with the uneven distribution of surface brightness, in order to enhance the image details. The Cr component images of YCbCr color space were extracted as the preprocessing samples to combine with the feature of the color of the apple. Secondly, the improved Otsu algorithm was utilized to obtain the binary image of the apple target for the initial segmentation, in order to accurately extract the contour of the target fruit under different growth states (mainly including single and double fruits with the overlap and occlusion). A morphological open-close reconstruction filter was also introduced to the Otsu algorithm to remove the background noise. The traversal range of the gray level was reduced to shorten the complexity and running time of the algorithm for the high segmentation rate. Thirdly, the watershed algorithm was combined to perform the secondary segmentation of the segmented fruit region using distance transformation. The conglutinated and overlapping apples were separated to effectively extract the apple target contour. Finally, the gradient Hough circle transformation was selected to identify the number of apples. But the algorithm traveled through the whole image for the computational complexity, time time-consuming, and easy to produce the false identification. Therefore, the minimum circumscribed rectangle outside the contour was set as the effective area for the gradient Hough circle transform in the effective area, particularly for the recognition speed and accuracy. The experimental results show that: 1) The improved Otsu algorithm was achieved in the higher segmentation accuracy of fruit targets, especially with the less segmentation time. The improved algorithm was also filled the tiny holes in the apple to suppress the noise in the background branches and leaves, further to more clearly segment the target region more than before. The average segmentation time was 1.458 s, which was 0.643 and 1.060 s shorter than the Otsu and K-means algorithm before the improvement. In the adhesion of partial apple regions in the binary images, a watershed segmentation with the distance transformation was used for the quadratic segmentation to effectively separate the sticky apples for the full apple target boundary. 2) The gradient Hough circle transform was used to recognize the 200 apple images under different lighting conditions, where the recognition accuracy was 90.75% in the nature natural light and 89.79% in the backlight, which were improved by 15.03 and 16.41 percentage points, respectively, compared with the traditional. The average recognition time was 0.665 and 0.693 s, which was 0.664 and 0.643 s shorter than before. Therefore, the proposed algorithm can meet the requirements of apple-picking robots, in terms of recognition speed and accuracy. The findings can provide a strong reference for the fast recognition of spherical fruits, such as apples. [ABSTRACT FROM AUTHOR]

Plant protection spraying has been the main way to prevent crops from pests and diseases at present. However, the average utilization rate of pesticides is only 20% to 30% in manual sprayers and large-capacity rain spraying, particularly with water consumption of 600-1 200 L/hm2 . The current pesticide spraying cannot fully meet the requirement of intensive agriculture in recent years. Among them, a large number of droplets with small particle sizes are susceptible to drifting by ambient wind. In this study, the mesh atomization of droplets was applied to reduce the wind drift for the high utilization rate of pesticides in the process of plant protection spraying. A systematic optimization was also made to investigate the secondary atomization characteristics of the droplets and the deposition effect of the droplets after the spray hits the mesh. The experimental variables were set as the pore size and the distance between the nozzle and the mesh. Phase Doppler Anemometry (PDA) was used to measure the velocity and particle size distribution of droplets after secondary atomization. A high-speed camera was selected to capture the spray angle. A 0.5 g/L methyl orange aqueous solution was prepared as a spray solution. The water-sensitive and filter tests were carried out to determine the droplet coverage and deposition amount, in order to evaluate the droplet deposition characteristics of the mesh atomization. The test results showed that: 1) the mesh effectively reduced the speed of the droplets. The average velocities of the measurement points were 1.80, 2.02, and 1.67 m/s under the mesh with pore sizes of 461, 350, and 227 μm, respectively. There were 23.40%, 13.90%, and 29.00% lower than those without the mesh (2.35 m/s). 2) The mesh reduced the particle size of the droplets. The maximum average particle sizes of the measurement points were 155.0, 165.6, and 173.3μm under the mesh with the pore size of 461, 350, and 227 μm, respectively, which were 19.5%, 14%, and 10% lower than those without the mesh (192.5 μm). 3) The spray angle of the droplet was varied in the pore size of the mesh and the distance between the nozzle and the mesh. Specifically, the maximum spray angle was 84.179° for the secondary atomized droplets at the pore size of 461 μm and the 10cm distance between the nozzle and the mesh, which was 20.366° larger than that without the mesh. 4) There was a great influence of pore size on the uniformity and penetration of the droplet deposition. The coefficient of variation of the deposition rate was between 33.51% and 88.08% at the sampling point of the mesh with the pore size of 350 and 227 μm, respectively, indicating similar deposition uniformity. By contrast, the maximum coefficient of variation of the deposition rate was 162.98% at the sampling points in each mesh layer with a pore size of 461 μm, indicating relatively less deposition uniformity. The better penetration of droplets was achieved in the mesh with the pore size of 350 μm, where the coefficient of variation of deposition between layers was between 0.8 % and 10.08 %. The better deposition was obtained in the mesh with the pore size of 461 μm in this case, compared with the pore size of 461 and 227 μm. There was no significant effect of the distance between the nozzle and the grid on the droplet coverage and deposition volume. In terms of the grids and large spraying droplets, the average droplet drift in the non-target area was 7.58 % of the deposition in the target area, indicating better performance after optimization. This finding can provide a strong reference to select the spraying and mesh parameters for the combination of plant protection UAV spray and mesh atomization. [ABSTRACT FROM AUTHOR]

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Copyright of Chinese Journal of Preventive Veterinary Medicine / Zhongguo Yufang Shouyi Xuebao is the property of Chinese Journal of Preventive Veterinary Medicine Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Irrigation & Drainage is the property of Journal of Irrigation & Drainage Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Poyang Lake is the property of Journal of Poyang Lake Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In intensive farming, the health of fish may be affected by many factors, especially when fish are exposed to a continuously deteriorating water environment and will face problems from various diseases. Vibrio disease is one of the most common bacterial diseases that can negatively impact shrimp, marine and freshwater fish farming, resulting in increased case fatality rates and serious economic losses. Probiotics, prebiotics and synbiotics have unique application effects in aquaculture, which can enhance the immune response of body and improve the resistance of fish to disease. The article reviews the types of common vibrosis in fish farming and the application of probiotics, prebiotics and synbiotics in preventing fish vibrosis, discusses its possible mechanism of action, to provide reference for the further application and research of probiotics, prebiotics and synbiotics to prevent fish vibrosis. [ABSTRACT FROM AUTHOR]

Multi-machine harvesting has been the popular form to improve the operation efficiency of the combine harvester, particularly with agricultural intensification, scale, and industrialization. The demand can also be required for the Internet of Things (IoT) and wireless communication of the combine harvester group. However, the current communication technologies of the IoT cannot fully meet the unstructured and large-scale agricultural scenarios, due mainly to the industrial design with the relatively short communication distance, low reliability, and high cost. Fortunately, the LoRa technology has unique advantages in the transmission distance, transmission rate, node capacity, and deployment mode. Moreover, the lower cost is suitable for the large-scale deployment of agricultural vehicles. At the same time, the parameters of LoRa technology can fully meet the needs of wireless communication in the operation scenario of combine harvester group. In addition, the 2.4 GHz band can further improve the performance of LoRa technology and regional universality. Therefore, wireless communication can be expected to apply to the scenario of combine harvester group. In this study, a communication network structure was proposed for the working mode of combine harvester group using the 2.4 GHz LoRa technology. Firstly, the LoRa network structure was constructed for the joint harvester cluster in the form of host and slave. The working mode of each node was then set using the cooperative operation scenario of the harvesters group. A radio frequency chip model (SX1280) was selected to simulate the transceiver mode, according to the application scenario. The optimal path attenuation model was chosen for the maximum communication distance between the master and slave. Secondly, a simulation model was established to optimize the application parameters of LoRa using NS-3 network platform, including the bandwidth, coding rate, spreading factor, transmission power, and frequency. The static and moving state of network nodes were used for the simulation scenarios of combine harvester communication network. Once the network nodes were fixed, a circular area with a radius of 3 km was selected as the deployment range of all network nodes. All network nodes were deployed in the circular range, according to the law of uniform distribution. The allocation scheme of spread spectrum factor was selected to accommodate the number of nodes and the minimum transmission interval in the simulated communication scenario of combine harvester cluster. Finally, the hardware and software were designed for the hardware terminal in the communication protocol of the combine harvester group. Both simulation and field experiments were conducted to comprehensively evaluate the effectiveness of the new LoRa for the combine harvesters group. The simulation results show that the spread spectrum factor with the specific proportion improved the network communication performance in the application scenario. When more than 90% of the reception success rate was guaranteed, the 1 625 kHz bandwidth supported by the 25 nodes to communicate at a 1 s transmission interval in a static scenario. In the dynamic scenario, the communication delay was less than 10 ms under 1 625 kHz bandwidth. The field test results show that the overall success rates of communication were 99.3%, and 92.5% under the “Report” and “Request” modes, respectively. The average response time was 123.07 ms. Consequently, the LoRa technology was applied for wireless communication between the combine harvesters, which can fully meet the requirements of joint harvester cluster communication for the number of accommodated devices and transmission interval. The number of nodes in the cluster can also be adjusted appropriately, according to the requirements for the communication interval. The Report mode supported the higher communication frequencies suitable for the reporting data from the combined harvesters, while the Request mode was suitable for the lower frequency, and responsive communications. The finding can provide a feasible solution to the mutual communication of the combine harvester clusters during cooperative operation. [ABSTRACT FROM AUTHOR]

With the gradual intensification of global warming, the impact of climate change on food security has attracted widespread concerns. Based on the panel data of 31 provinces from 1990 to 2020, the article analyzed the development trends of climate change and food security based on the analysis of the relationship between climate change and food security. This article constructed a food security index system from four dimensions of food availability, accessibility, utilization, and stability, using methods of range standardization, weighing of variation coefficients, and the radar-area model analysis to calculate the food security index, and empirically verified the impact mechanism of climate change on food security. The study found that: ① Two major climatic factors, namely accumulated temperature and precipitation, had inhibitory effects on food security. Accumulated temperature had a negative impact on food security at the 1% significance level, and precipitation had an adverse effect on food security at the 5% significance level. ② The regulating effect of agricultural technology was mainly reflected in that it weakened the inhibitory effect of accumulated temperature on food security, but the moderating effect in the process during which precipitation affected food security was not obvious. ③ In terms of sub-regions, climate change had the greatest negative impact on food security in areas with balanced grain production and marketing, while the inhibitory effect on food security in main grain producing areas and main grain marketing areas was not obvious; agricultural technology played the strongest regulatory role in main grain producing areas, and the moderating effect in main grain marketing areas and areas with balanced grain production and marketing was not obvious. To ensure food security, it is necessary to strengthen the ability to deal with climate change, gradually improve the management mechanism of grain reserves, implement the policy of ‘food crop production strategy based on technological application,’ adjust the grain farming system and planting structure according to local conditions, cultivate excellent crop varieties, and promote the transformation and popularization of modern agricultural technology. In the meanwhile, different functional areas of grain production should give full play to their regional advantages: main grain producing areas should promote the optimization of grain production and operations and improve the comprehensive capacity of grain production; main grain marketing areas should give full play to their economic and technological advantages and develop intensive and modern agriculture to increase the self-sufficiency rate of grain; areas with balanced grain production and marketing need to focus on improving the farmers’ ability to resist risks and motivate them to engage in grain production so as to maintain the balance between regional production and marketing. [ABSTRACT FROM AUTHOR]

Copyright of Asian Journals of Ecotoxicology is the property of Gai Kan Bian Wei Hui and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Science & Technology of Cereals, Oils & Foods is the property of Science & Technology of Cereals, Oils & Foods Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Chinese Journal of Preventive Veterinary Medicine / Zhongguo Yufang Shouyi Xuebao is the property of Chinese Journal of Preventive Veterinary Medicine Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Central China Normal University is the property of Huazhong Normal University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Agro-Environment Science is the property of Journal of Agro-Environment Science Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Agriculture is directly related to food security, which is highly dependent on and significantly impacts resources and the environment. Sustainable agriculture development is key to achieving the sustainable development goals. Frontiers, hot topics, and trends of sustainable agriculture development were summarized for scientific research and decision-making by CiteSpace based on 1 174 papers published in the Web of Science and 1 043 papers published in China National Knowledge Infrastructure from 2000 to 2019. Results showed that the frontiers were mainly focused on“food system resilience and food security”,“ecological intensification and sustainable intensification”,“agricultural muti-functionality and urban agriculture”, and“trade-offs and synergies of ecosystem services in agroecosystem”. Hotspots included how climate change impacts agricultural systems and its adaptive management, ecosystem services management in agro-ecosystems, and the environmental impact assessment of agricultural activities and integrated sustainability assessment of an agricultural system. It is suggested that the coupling mechanism of the“climate-land-water-energy-food”nexus should be further analyzed, and“influencing factors-action mechanisms-regulation methods”of agro-ecosystem should be systematically studied in the future. [ABSTRACT FROM AUTHOR]

With the rapid development of China's economy, the large-scale breeding industry has developed rapidly. Due to the heavy metal elements added to feed, the manure produced by intensive farming exerts huge environmental pressure on the farmland soil. Composting is an effective treatment measure to passivate heavy metals in manure. Adding inorganic, organic, and biological passivators to compost can fix heavy metals and reduce their biological effectiveness. The mechanism of the passivation materials used in the current research needs to be explored deeply, and the process of heavy metal migration and transformation and the interaction with the soil after passivation compost is applied to the soil is still unclear. This should be an important research topic in the future. Based on the presence of heavy metals in manure, the transformation of heavy metal during composting, and the passivation mechanism of passivators, we discussed the transformation mechanism of manure-passivated heavy metals in soil, and then provided scientific analysis for the safe application of manure. [ABSTRACT FROM AUTHOR]

Consumption of petroleum resource has risen sharply in recent years with the increase in fuel vehicles and heavy machinery in mechanized intensive agriculture. A large amount of emitted pollution has posed a serious threat to the atmospheric environment, even to body health in human survival. Water-in-oil (W/O) emulsified diesel fuel has received widespread attention for its ability to simultaneously remove nitrogen oxides and particulate matter. The micro-explosive characteristics of W/O fuel depend strongly on the diameter of the water core. But a systematic solution is still lacking in the preparation of W/O emulsified fuel for the target diameter of the water core at the constant component content. In this study, an image recognition system was first developed suitable for the microstructure of the water core in the W/O emulsified fuel using the Chan–Vese (CV) model. A log-normal function was proposed to fit the diameter distribution of the water core in the W/O emulsified fuel, thereby obtaining a new combination of characteristic parameters. An orthogonal test was selected to explore the influence of emulsification parameters on the diameter of the water core, including the emulsification time, emulsification power, and frequency parameters. The optimal parameters were achieved to fabricate the W/O emulsion with the target diameter of the water core. The results show that the CV model better identified the discrete boundary of the water core with smaller error, compared with manual recognition. The characteristics parameters from the lognormal function fitting can describe more accurately the diameter distribution of the water core in the W/O emulsified fuel, compared with the Sauter Mean Diameter (SMD). The maximum diameter of the water core and the standard deviation of diameter distribution gradually decreased, while the ultrasonic frequency imposed a relatively weak influence on the W/O emulsified fuel, as the emulsification time and power increased. When the diameter of the water core and the distribution reached a critical value, there was much more effect of emulsification power on the diameter of water core and the distribution, compared with the emulsification time with the same energy. In addition, there was no change in the maximum diameter of the water core. The ratios of three preparation factors (ultrasonic frequency, emulsification power, and emulsification time) to the maximum fitting diameter were 0.744, 2.88, and 1.038, respectively. The standard deviations of distribution were 0.028, 0.120, and 0.034, respectively. The priority of three parameters was ranked in order: emulsification power > emulsification time > ultrasonic frequency. [ABSTRACT FROM AUTHOR]

BACKGROUND: With the advancement of agricultural intensification and urbanization, pesticide residues in a large numbers of water environments in the world have exceeded the prescribed limit. The issue of pesticide pollution in the water environment has received extensive attention from all sectors of society. As the largest pesticide producer and user country in the world, the amount of pesticide residues in the water environment in China is much higher than other developed countries. Available studies have detected 19 pesticides in seven typical river basins in China (the Yangtze River, Taihu Lake, Yellow River, Songhua River, Heilongjiang, Grand Canal and Dongjiang), with an average concentration ranging from 0. 02 to 332. 75ng/L. Pesticides and their transformation products pose potential threats to the ecological environment and human health. Research on pesticide residues in the water environment is an indispensable part of water quality assessment. However, targeted screening is difficult to detect unknown pesticides and their transformation products. Therefore, the non - targeted screening of pesticide residues and their transformation products in the environment needs to be improved. OBJECTIVES: To understand the pesticide pollution analysis techniques for environmental water samples. METHODS: According to the analysis process of non - targeted screening of pesticide components, the targeted and non - targeted screening methods for pesticide residues in water quality samples in the past 5 years were reviewed, and the regulations and standards for pesticide residue limits and non - targeted screening of pesticides in water quality were summarized. The research progress of pesticide residue analysis methods in water environment in recent years was summarized. RESULTS: The characteristics of liquid - liquid extraction ( LLE), solid - phase extraction ( SPE), solid - phase microextraction ( SPME) and other pre - treatment methods were reviewed. Among them, solid - phase extraction was the main pre - treatment method for non - targeted pesticide screening and had good applications prospects. The development trend of analytical instruments from chromatography to chromatography mass spectrometry was discussed, and the production of a variety of high - resolution mass spectrometry provided multi - level analysis requirements for non - targeted pesticide screening. Finally, the guidelines, mass spectrometry database and various identification methods related to pesticide screening confirmation in recent years were summarized, and the development trend of pesticide pollution analysis technology in the water environment was prospected. CONCLUSIONS: High resolution mass spectrometry technology poses a challenge to the sample pretreatment and purification process. The combination of multiple technologies in the water sample pretreatment process is the future development trend. Research on non - targeted pesticide screening based on high - resolution mass spectrometry is widely studied in the field of food testing although it has low priority in the environmental field. Relevant organizations at home and abroad have not yet issued relevant standards for screening and confirmation of unknown substances. Currently, the confirmation of unknown screening requires manual data analysis, which cannot be fully automated. [ABSTRACT FROM AUTHOR]

Crop straw is a valuable biomass energy resource and raw material for livestock forage, organic fertilizer and industrial use. However, the comprehensive utilization level of straw resources in China is not high due to various reasons including agricultural intensification, capital shortage and farmers’ cognition. Regional, seasonal and structural surplus of crop straw is common in China and a lot of straw is discarded and burned casually, especially in rural areas. It is not only a huge waste of resources, but also leads to serious atmosphere and soil environment pollutions. Thus, it is of great importance to improve the straw utilization rate. That take regional planning as a whole and realize full utilization of the regional total straw resources is a good strategy. Assessment of regional straw resources’ quantity, type, and distribution pattern is the prerequisite to achieve regional straw resources full utilization. In addition, the utilization modes and levels of straw resources are also restricted by many other factors including the social and economic development status. Thus, to make better use of straw resources and optimize utilization structure, it is necessary to take all the above factors into comprehensive consideration, carrying out scientific layout and rational planning. Hunan province is an important agricultural province and also a main producing area of double cropping rice in China. The present study estimated the straw quantity and amount per capita of the main crops in Hunan province. The spatial distribution patterns of straw resources in Hunan province were also analyzed. In addition, the paper also analyzed the potential of full utilization of the total straw resources in the province through comparing the current straw utilization structure and quantities with their corresponding competitive straw demands. The results showed that the theoretical and collectable amount of the main crop straw resources in Hunan province in 2018 were 4 021.7× 104 t and 3 039.1×104 t, respectively. The mean amount per capita of straw resource is only 0.68 t, which is much lower than the national average level. The straw of rice, rape, maize and vegetables accounted for 64.7%, 16.0%, 6.1% and 7.5% of the total straw resources of the Province, respectively. The various types of crop straws exhibited different spatial distribution patterns. The amount of rice, rape and vegetable straw increased from west to east and south to north in the province, whereas corn straw displayed an opposite distribution trend. Through estimating the potential utilization ways of straw resources, the competitive demand of straw in Hunan province included 887.3×104 t for fertilizer, 885.1×104 t for fodder, 65.7×104 t for raw material and 83.2×104 t for stroma material. The remaining amount of straw for potential energy utilization was 1 117.9×104 t. Considering the current straw utilization structure and the results as above, the overall trend of realizing full utilization in the province should be to improve the ratio of fodder and energy utilization and slightly reduce fertilizer utilization on the basis of maintaining the amount for stroma and raw material utilization. [ABSTRACT FROM AUTHOR]

Urbanization in current China has brought profound changes in every phase of social life and modern agriculture. Specifically, the rural labor migration to cities and towns has posed a significant challenge on the contract management between household and cultivated land during agricultural modernization. The transfer of rural contracted land-use rights is gradually becoming a heat dispute in the basic rural management system. The stable land contract relationships need to be maintained in the countryside over the long term, while it also needs to strengthen supervision of and services related to the exit of rural contracted land-use rights for the standardized and intensive agriculture. During this time, the withdrawal rights of farmers' land contract can be a major management measure in China's rural land reform, in order to promote the moderate urbanization of rural land on a larger scale. In this study, seven exit modes in scenario simulations were established to analyze the exit decision-making of farmers under different conditions based on the exit policies that have been implemented in some typical pilot areas in the country. Survey questionnaires from 279 field farmers were made to clarify the influencing factors of farmers’ exit decisions on different modes under scenario simulation. A single factor analysis was used to analyze the 16 potential influencing factors from the four feature dimensions in turn, where a Chi-square test was utilized to evaluate the significant level of the variables for the selection of the single factor analysis in the multiple order. A Logistic regression was used to reveal the factors that influence farmers' decision-making on the withdrawal of land contractual management rights. The results show that: 1) Under different scenarios, the interviewed farmers have various willingness to accept the exit mode. In the exit modes that implemented in Neijiang, Sichuan and Chengdu, Sichuan, farmers expressed their willingness to accept accounted for 63.08% (Neijiang mode) and 53.05% (Chengdu mode) of the total sample. The acceptance rate of farmers was similar in Pingluo mode of 16.49% and in Meitan mode of 18.28%. There was a lowest acceptance rate of farmers in the Jinhu mode. A conservative attitude can occur in the farmers' exit decisions under various scenarios. The withdrawal decision of land tenure was mainly focused on the single-item exit and long-term exit of land contractual management rights, while the exit mode of “three rights withdrawal” was more cautious for the farms. 2) The regression results show that there are various influencing factors of farmers’ decision-making on exiting from different scenarios. The variable expected risk level has a significant impact on the exit decisions in the seven scenarios. If farmers feel that the expected risk level is relatively low, they are generally more inclined to withdraw from land contractual management rights. The ability of risk avoidance was stronger in other scenarios than that in the Wenjiang mode. If farmers think that they cannot afford the risk of exit completely, they usually choose not to quit the right of contract land. The type of household has a positive impact on the exit decisions in the Neijiang, Wenjiang and Chengdu modes, whereas, the quit willingness was even strong in the non-farm households. Whether there was abandonment or idleness in the contracted land has a significant impact on the Liangping, Meitan and Jinhu modes. Specifically, farmers with abandonment or idleness land were more willing to withdraw from land contractual management rights. This finding can provide policy implications for the establishment of diversified exit modes to clarify withdrawal mechanism of land contraction management right. [ABSTRACT FROM AUTHOR]

There has a drastic change in structures of agricultural production and rural economy in China over the recent years. Pollution induced by agrochemical applications, livestock and poultry breeding, straw incineration in agricultural production has been increasing, and agricultural pollution has overtaken industrial pollution becoming the main water pollution source in China. However, efforts to ameliorate these pollutions are difficult to implement because of a lack of understanding of their associated costs. This is one reason why agricultural pollution control is still regulation-based rather than market-based as has been widely used in controlling industrial pollution. Shadow price of agricultural pollutant is a key to help policy-make strategies to remediate agricultural pollutants. The purpose of this paper is to address this issue by taking agricultural data measured from 1978 to 2017 at provincial scale in China as an example. We estimated the quadratic directional distance function, revenue function and the costs of pollution in agricultural production. The results showed that the shadow prices of total nitrogen (TN), total phosphorus (TP) and COD had reduced by 26.8%, 35.9% and 59.7%, respectively, from 1978 to 2017, having undergone through free development stage, reform promotion stage, market regulation stage and policy incentive stage. Because of the difference in natural and socio-economic conditions between the provinces, there was a noticeable spatial variation in shadow prices of agricultural pollutants in them. In the northwest China, the shadow price of TN was the lowest, while in the southwest China, the shadow price of TN and TP was the highest and the price of COD was the lowest. In east China the shadow price of TP was the lowest and the price of COD was the highest. The average annual costs of pollution in agricultural production was 76.06 billion Yuan per year, accounting for 10.8% of the value of the total agricultural production. In particular, the costs of pollution in Ningxia, Guizhou, Hebei, and Shandong accounted for more than 14% of the value of their total annual agricultural production. The long-term change in shadow price of agricultural pollutants and the costs of agricultural pollution in China indicated that agricultural production was complex and affected by individual and combined natural, social-economic and political factors. Agricultural policies should be made based on the requirement of the "two-oriented agriculture" development by reforming agricultural supply structure to improve quality and efficiency of the agricultural supply to avoid falling into the "profit pursuing policy" trap. Transformation of agricultural production should focus on improving land productivity and resource and labor use efficiency, along with reducing dependence on petrochemicals and remediating non-point agricultural pollutant. It also needs to consider resource conservation and environmental protection by developing circular, and ecological-friendly intensive agriculture. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Southern Agriculture is the property of Journal of Southern Agriculture and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Agro-Environment Science is the property of Journal of Agro-Environment Science Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)