C. Hay, B. Reinhart, J. Frankenberger, M. Helmers, X. Jia, K. Nelson, M. Youssef
HighlightsDrainage water recycling captures and stores agricultural drainage water for reuse as supplemental irrigation.Drainage water recycling can both increase crop production and benefit downstream water quality.Depending on management, drainage water recycling can also provide other complementary benefits.Research needs to advance drainage water recycling are presented and discussed. Keywords: Drainage water quality, Drainage water reuse, Subsurface drainage, Supplemental irrigation, Agricultural resiliency.
{"title":"Frontier: Drainage Water Recycling in the Humid Regions of the U.S.: Challenges and Opportunities","authors":"C. Hay, B. Reinhart, J. Frankenberger, M. Helmers, X. Jia, K. Nelson, M. Youssef","doi":"10.13031/trans.14207","DOIUrl":"https://doi.org/10.13031/trans.14207","url":null,"abstract":"HighlightsDrainage water recycling captures and stores agricultural drainage water for reuse as supplemental irrigation.Drainage water recycling can both increase crop production and benefit downstream water quality.Depending on management, drainage water recycling can also provide other complementary benefits.Research needs to advance drainage water recycling are presented and discussed. Keywords: Drainage water quality, Drainage water reuse, Subsurface drainage, Supplemental irrigation, Agricultural resiliency.","PeriodicalId":23120,"journal":{"name":"Transactions of the ASABE","volume":"43 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82787014","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Dujin Wang, Yizhong Wang, Ming Li, Xinting Yang, Jianwei Wu, Wenyong Li
Highlights The proposed method detected thrips and whitefly more accurately than previous methods. The proposed method demonstrated good robustness to illumination reflections and different pest densities. Small pest detection is improved by adding large-scale feature maps and more residual units to a shallow network. Machine vision and deep learning create an end-to-end model to detect smallsmall pests on sticky traps in field conditions. Abstract. Pest detection is the basis of precise control in vegetable greenhouses. To improve the detection accuracy and robustness of two common small pests in greenhouses, whitefly and thrips, this study proposes a novel small object detection approach based on the YOLOv4 model. Yellow sticky trap (YST) images at the original resolution (2560x1920 pixels) were collected using a pest monitoring equipment in a greenhouse. They were then cropped and labeled to create the sub-images (416x416 pixels) to construct an experimental dataset. The labeled images of this study (900 training, 100 validation, and 200 test) are available for comparative studies. To enhance the model‘s ability to detect small pests, the feature map at the 8-fold downsampling layer in the backbone network was merged with the feature map at the 4-fold downsampling layer to generate a new layer and output a feature map with a size of 104x104 pixels. Furthermore, the residual units in the first two residual blocks are enlarged by four times to extract more shallow image features and the location information of target pests to withstand image degradation in the field. The experimental results show that the detection mAP of whitefly and thrips using the proposed approach is improved by 8.2% and 3.4% compared with the YOLOv3 and YOLOv4 models, respectively. The detection performance slightly decreases as the pest densities increase in the YST image, but the mAP value was still 92.7% in the high-density dataset, which indicates that the proposed model has good robustness over a range of pest densities. Compared with some previous similar studies, the proposed method has better potential to monitor whitefly and thrips using YSTs in field conditions.
{"title":"Using an Improved YOLOv4 Deep Learning Network for Accurate Detection of Whitefly and Thrips on Sticky Trap Images","authors":"Dujin Wang, Yizhong Wang, Ming Li, Xinting Yang, Jianwei Wu, Wenyong Li","doi":"10.13031/TRANS.14394","DOIUrl":"https://doi.org/10.13031/TRANS.14394","url":null,"abstract":"Highlights The proposed method detected thrips and whitefly more accurately than previous methods. The proposed method demonstrated good robustness to illumination reflections and different pest densities. Small pest detection is improved by adding large-scale feature maps and more residual units to a shallow network. Machine vision and deep learning create an end-to-end model to detect smallsmall pests on sticky traps in field conditions. Abstract. Pest detection is the basis of precise control in vegetable greenhouses. To improve the detection accuracy and robustness of two common small pests in greenhouses, whitefly and thrips, this study proposes a novel small object detection approach based on the YOLOv4 model. Yellow sticky trap (YST) images at the original resolution (2560x1920 pixels) were collected using a pest monitoring equipment in a greenhouse. They were then cropped and labeled to create the sub-images (416x416 pixels) to construct an experimental dataset. The labeled images of this study (900 training, 100 validation, and 200 test) are available for comparative studies. To enhance the model‘s ability to detect small pests, the feature map at the 8-fold downsampling layer in the backbone network was merged with the feature map at the 4-fold downsampling layer to generate a new layer and output a feature map with a size of 104x104 pixels. Furthermore, the residual units in the first two residual blocks are enlarged by four times to extract more shallow image features and the location information of target pests to withstand image degradation in the field. The experimental results show that the detection mAP of whitefly and thrips using the proposed approach is improved by 8.2% and 3.4% compared with the YOLOv3 and YOLOv4 models, respectively. The detection performance slightly decreases as the pest densities increase in the YST image, but the mAP value was still 92.7% in the high-density dataset, which indicates that the proposed model has good robustness over a range of pest densities. Compared with some previous similar studies, the proposed method has better potential to monitor whitefly and thrips using YSTs in field conditions.","PeriodicalId":23120,"journal":{"name":"Transactions of the ASABE","volume":"7 1","pages":"0"},"PeriodicalIF":1.5,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91309553","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
HighlightsWe developed and evaluated a variable-rate irrigation (VRI) management method for five crop years in the Mississippi Delta.VRI management significantly reduced irrigation water use in comparison with uniform-rate irrigation (URI). There was no significant difference in grain yield and irrigation water productivity between VRI and URI management.Soil apparent electrical conductivity (ECa) was used to delineate irrigation management zones and generate VRI prescriptions.Sensor-measured soil water content was used in irrigation scheduling.Abstract. Variable-rate irrigation (VRI) allows producers to site-specifically apply irrigation water at variable rates within a field to account for the temporal and spatial variability in soil and plant characteristics. Developing practical VRI methods and documenting the benefits of VRI application are critical to accelerate the adoption of VRI technologies. Using apparent soil electrical conductivity (ECa) and soil moisture sensors, a VRI method was developed and evaluated with corn and soybean for five crop years in the Mississippi Delta. Soil ECa of the study fields was mapped and used to delineate VRI management zones and create VRI prescriptions. Irrigation was scheduled using soil volumetric water content measured by soil moisture sensors. A center pivot VRI system was employed to deliver irrigation water according to the VRI prescription. Grain yield, irrigation water use, and irrigation water productivity in the VRI treatment were determined and compared with that in a uniform-rate irrigation (URI) treatment. Results showed that the grain yield and irrigation water productivity between the VRI and URI treatments were not statistically different with both corn and soybean crops. The VRI management significantly reduced the amount of irrigation water by 22% in corn and by 11% in soybean (p = 0.05). Adoption of VRI management could improve irrigation water use efficiency in the Mississippi Delta. Keywords: Soil electrical conductivity, Soil moisture sensor, Variable rate irrigation, Water management.
{"title":"Development and Evaluation of a Variable-Rate Irrigation Management Method in the Mississippi Delta","authors":"R. Sui, J. Baggard","doi":"10.13031/TRANS.14019","DOIUrl":"https://doi.org/10.13031/TRANS.14019","url":null,"abstract":"HighlightsWe developed and evaluated a variable-rate irrigation (VRI) management method for five crop years in the Mississippi Delta.VRI management significantly reduced irrigation water use in comparison with uniform-rate irrigation (URI). There was no significant difference in grain yield and irrigation water productivity between VRI and URI management.Soil apparent electrical conductivity (ECa) was used to delineate irrigation management zones and generate VRI prescriptions.Sensor-measured soil water content was used in irrigation scheduling.Abstract. Variable-rate irrigation (VRI) allows producers to site-specifically apply irrigation water at variable rates within a field to account for the temporal and spatial variability in soil and plant characteristics. Developing practical VRI methods and documenting the benefits of VRI application are critical to accelerate the adoption of VRI technologies. Using apparent soil electrical conductivity (ECa) and soil moisture sensors, a VRI method was developed and evaluated with corn and soybean for five crop years in the Mississippi Delta. Soil ECa of the study fields was mapped and used to delineate VRI management zones and create VRI prescriptions. Irrigation was scheduled using soil volumetric water content measured by soil moisture sensors. A center pivot VRI system was employed to deliver irrigation water according to the VRI prescription. Grain yield, irrigation water use, and irrigation water productivity in the VRI treatment were determined and compared with that in a uniform-rate irrigation (URI) treatment. Results showed that the grain yield and irrigation water productivity between the VRI and URI treatments were not statistically different with both corn and soybean crops. The VRI management significantly reduced the amount of irrigation water by 22% in corn and by 11% in soybean (p = 0.05). Adoption of VRI management could improve irrigation water use efficiency in the Mississippi Delta. Keywords: Soil electrical conductivity, Soil moisture sensor, Variable rate irrigation, Water management.","PeriodicalId":23120,"journal":{"name":"Transactions of the ASABE","volume":"6 1","pages":"287-298"},"PeriodicalIF":1.5,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73231415","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
HighlightsFilter strip processes for water pollutant reductions were quantified from 74 studies with almost 300 data points.Regression was significant versus width (sediment, N, P), area ratio (sediment, atrazine), and Ks (N, P, atrazine, alachlor).This review discusses ten functional factors affecting FS efficiency as well as FS monitoring recommendations.Cost-effectiveness was assessed and varies considerably by influent load and treatment effectiveness.Abstract. Filter strips (FSs) are edge-of-field conservation practices commonly implemented to reduce flux of sediment, nutrients, and other constituents from agricultural fields. While various aspects of FS effectiveness have been reviewed, this study provides a comprehensive summary of FS efficiency data for sediment, nutrients, pesticides, and pathogens as part of a special collection focused on agricultural conservation practices. This analysis also fills an important gap by assessing performance-based FS costs and cost-effectiveness. Data from 74 U.S. and international studies with 294 different treatments and 3,050 replications were compiled and analyzed. Results showed that runoff reduction tended to increase with increasing FS width up to about 15 m and that sediment reduction was significantly related to the ratio of FS area to drainage area and to FS width, with reduction tending to increase with increasing width up to about 20 m. Total P reduction was significantly related to FS soil saturated hydraulic conductivity, and total N reduction was significantly related to both saturated hydraulic conductivity and width. Total P and total N reductions both tended to increase with increasing FS width up to about 20 m and with increasing FS slope up to about 10%. Annualized FS costs were estimated to range from $314 to $865 ha-1 year-1 for different FS implementations. A major component of the cost is the opportunity cost of taking land out of production. Costs per unit of sediment retained by FS systems ranged from $10.3 to $18.6 Mg-1. A comprehensive assessment of FS cost-effectiveness (cost:benefit) is needed. Monitoring equipment, approaches, and recommendations are discussed, acknowledging the challenges of implementing field-scale FS studies. This information is critical to guide on-farm and programmatic FS decisions and to increase the scientific understanding of this commonly used agricultural conservation practice. Keywords: Best management practice, Buffer strip, Nonpoint-source pollution, Riparian buffer, Vegetated filter strip.
{"title":"Review of Filter Strip Performance and Function for Improving Water Quality from Agricultural Lands","authors":"K. Douglas-Mankin, M. Helmers, R. Harmel","doi":"10.13031/TRANS.14169","DOIUrl":"https://doi.org/10.13031/TRANS.14169","url":null,"abstract":"HighlightsFilter strip processes for water pollutant reductions were quantified from 74 studies with almost 300 data points.Regression was significant versus width (sediment, N, P), area ratio (sediment, atrazine), and Ks (N, P, atrazine, alachlor).This review discusses ten functional factors affecting FS efficiency as well as FS monitoring recommendations.Cost-effectiveness was assessed and varies considerably by influent load and treatment effectiveness.Abstract. Filter strips (FSs) are edge-of-field conservation practices commonly implemented to reduce flux of sediment, nutrients, and other constituents from agricultural fields. While various aspects of FS effectiveness have been reviewed, this study provides a comprehensive summary of FS efficiency data for sediment, nutrients, pesticides, and pathogens as part of a special collection focused on agricultural conservation practices. This analysis also fills an important gap by assessing performance-based FS costs and cost-effectiveness. Data from 74 U.S. and international studies with 294 different treatments and 3,050 replications were compiled and analyzed. Results showed that runoff reduction tended to increase with increasing FS width up to about 15 m and that sediment reduction was significantly related to the ratio of FS area to drainage area and to FS width, with reduction tending to increase with increasing width up to about 20 m. Total P reduction was significantly related to FS soil saturated hydraulic conductivity, and total N reduction was significantly related to both saturated hydraulic conductivity and width. Total P and total N reductions both tended to increase with increasing FS width up to about 20 m and with increasing FS slope up to about 10%. Annualized FS costs were estimated to range from $314 to $865 ha-1 year-1 for different FS implementations. A major component of the cost is the opportunity cost of taking land out of production. Costs per unit of sediment retained by FS systems ranged from $10.3 to $18.6 Mg-1. A comprehensive assessment of FS cost-effectiveness (cost:benefit) is needed. Monitoring equipment, approaches, and recommendations are discussed, acknowledging the challenges of implementing field-scale FS studies. This information is critical to guide on-farm and programmatic FS decisions and to increase the scientific understanding of this commonly used agricultural conservation practice. Keywords: Best management practice, Buffer strip, Nonpoint-source pollution, Riparian buffer, Vegetated filter strip.","PeriodicalId":23120,"journal":{"name":"Transactions of the ASABE","volume":"3 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88594468","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Chengda Sun, Weimin Ding, Changding Liu, Weifeng Yao, Lilian Shi
HighlightsA measurement device for droplet mass deposit was improved to enhance its performance.A wireless data transmission system was used to achieve convenient data sharing.A user interface was designed for display and analysis of the measurement results.A positioning mechanism was designed for arranging measurement devices promptly.Abstract. Measurement of droplet mass deposit is important in spray research and spray performance evaluation. In this article, an online measurement device for droplet mass deposit was improved based on the original design. The measurement resolution, precision, and data stability were improved by optimization of the structure and components and by data filtering. The resolution reached 0.00067 mg cm-2. Comparison tests showed that the relative error between the original device and an analytical balance was 6.68% to 8.48%, and the relative error between the improved device and the analytical balance was 5.24% to 6.15%. Compared with the original device, the relative error decreased and the precision improved. The relative error between the improved device and a tracer method was 5.11% to 6.99%, and the precision of the improved device was close to that of the tracer method. A positioning mechanism was designed to arrange measurement devices promptly in the test area, and a wireless data transmission system was used to achieve convenient data sharing. A user interface was designed to display the results in the form of tables and contour maps. Tests were conducted to measure the droplet mass deposit distribution of one nozzle, the droplet mass deposit distribution in a tree canopy, and the uniformity of the droplet mass deposit distribution in a small horizontal area. The results showed that the improved measurement device could provide data promptly and conveniently for spray research and spray performance evaluation. Keywords: Device improvement, Mass distribution, Wireless communication.
{"title":"Improvement and Experiment for Online Measurement of Droplet Mass Deposit","authors":"Chengda Sun, Weimin Ding, Changding Liu, Weifeng Yao, Lilian Shi","doi":"10.13031/trans.14219","DOIUrl":"https://doi.org/10.13031/trans.14219","url":null,"abstract":"HighlightsA measurement device for droplet mass deposit was improved to enhance its performance.A wireless data transmission system was used to achieve convenient data sharing.A user interface was designed for display and analysis of the measurement results.A positioning mechanism was designed for arranging measurement devices promptly.Abstract. Measurement of droplet mass deposit is important in spray research and spray performance evaluation. In this article, an online measurement device for droplet mass deposit was improved based on the original design. The measurement resolution, precision, and data stability were improved by optimization of the structure and components and by data filtering. The resolution reached 0.00067 mg cm-2. Comparison tests showed that the relative error between the original device and an analytical balance was 6.68% to 8.48%, and the relative error between the improved device and the analytical balance was 5.24% to 6.15%. Compared with the original device, the relative error decreased and the precision improved. The relative error between the improved device and a tracer method was 5.11% to 6.99%, and the precision of the improved device was close to that of the tracer method. A positioning mechanism was designed to arrange measurement devices promptly in the test area, and a wireless data transmission system was used to achieve convenient data sharing. A user interface was designed to display the results in the form of tables and contour maps. Tests were conducted to measure the droplet mass deposit distribution of one nozzle, the droplet mass deposit distribution in a tree canopy, and the uniformity of the droplet mass deposit distribution in a small horizontal area. The results showed that the improved measurement device could provide data promptly and conveniently for spray research and spray performance evaluation. Keywords: Device improvement, Mass distribution, Wireless communication.","PeriodicalId":23120,"journal":{"name":"Transactions of the ASABE","volume":"5 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88055536","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
HighlightsPermittivity measurements were taken for traditional and high-oleic runner-type peanut pods and kernels at microwave frequencies.The dielectric constant, loss factor, loss tangent, and complex plane were compared between the two cultivars to observe any effect caused by the high-oleic trait.Despite differences in composition, minimal to no differences were observed in permittivity between the two cultivars.Abstract. Different cultivars of peanuts containing higher amounts of oleic acid have been developed to improve oxidative stability and overall peanut quality. Increasing oleic acid levels and decreasing linoleic acid levels in peanuts deter lipid oxidation, preventing the creation of off-flavors and increasing the shelf life. Since their conception, high-oleic peanuts have been tested from chemical and sensory perspectives to observe differences between them and traditional peanuts. Such tests have shown minimal differences, if any. However, tests to observe the effect of changing the levels of oleic and linoleic acid on permittivity, which is often used for nondestructive determination of the moisture content and bulk density of foods and agricultural products, have not been reported. Thus, a vector network analyzer (VNA) was used to take free-space transmission measurements of the complex permittivities of high-oleic and traditional runner-type peanut pods and kernels. Measurements were taken at 23°C between 5 and 9 GHz. Measurements yielded the dielectric constant and loss factor, which are often correlated to moisture content. Analysis was performed to compare the changes in the dielectric constant, loss factor, and loss tangent with moisture content for high-oleic and traditional peanuts. Linear trends were observed for each parameter with increasing moisture content for both cultivars. Results from the complex plane showed coefficient of determination (r2) values greater than 0.9 for pods and kernels. Therefore, at microwave frequencies, changing the levels of oleic and linoleic acid within the peanuts was observed to have minimal to no effect on their permittivity. Thus, moisture calibrations based on correlations between dielectric properties and moisture content for traditional runner-type peanuts can be applied to high-oleic cultivars. Keywords: Dielectric properties, Free-space transmission measurements, Microwave measurements, Oleic acid, Peanut kernels, Peanut pods.
{"title":"Comparison of Dielectric Properties of Traditional and High-Oleic Runner-Type Peanuts at Microwave Frequencies","authors":"M. Lewis, S. Trabelsi","doi":"10.13031/trans.14323","DOIUrl":"https://doi.org/10.13031/trans.14323","url":null,"abstract":"HighlightsPermittivity measurements were taken for traditional and high-oleic runner-type peanut pods and kernels at microwave frequencies.The dielectric constant, loss factor, loss tangent, and complex plane were compared between the two cultivars to observe any effect caused by the high-oleic trait.Despite differences in composition, minimal to no differences were observed in permittivity between the two cultivars.Abstract. Different cultivars of peanuts containing higher amounts of oleic acid have been developed to improve oxidative stability and overall peanut quality. Increasing oleic acid levels and decreasing linoleic acid levels in peanuts deter lipid oxidation, preventing the creation of off-flavors and increasing the shelf life. Since their conception, high-oleic peanuts have been tested from chemical and sensory perspectives to observe differences between them and traditional peanuts. Such tests have shown minimal differences, if any. However, tests to observe the effect of changing the levels of oleic and linoleic acid on permittivity, which is often used for nondestructive determination of the moisture content and bulk density of foods and agricultural products, have not been reported. Thus, a vector network analyzer (VNA) was used to take free-space transmission measurements of the complex permittivities of high-oleic and traditional runner-type peanut pods and kernels. Measurements were taken at 23°C between 5 and 9 GHz. Measurements yielded the dielectric constant and loss factor, which are often correlated to moisture content. Analysis was performed to compare the changes in the dielectric constant, loss factor, and loss tangent with moisture content for high-oleic and traditional peanuts. Linear trends were observed for each parameter with increasing moisture content for both cultivars. Results from the complex plane showed coefficient of determination (r2) values greater than 0.9 for pods and kernels. Therefore, at microwave frequencies, changing the levels of oleic and linoleic acid within the peanuts was observed to have minimal to no effect on their permittivity. Thus, moisture calibrations based on correlations between dielectric properties and moisture content for traditional runner-type peanuts can be applied to high-oleic cultivars. Keywords: Dielectric properties, Free-space transmission measurements, Microwave measurements, Oleic acid, Peanut kernels, Peanut pods.","PeriodicalId":23120,"journal":{"name":"Transactions of the ASABE","volume":"482 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86763616","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
L. Ye, Yadong Zhang, Jian Zhao, Xia Zhao, Jianshe Li, Zhangying Ye
HighlightsLight design is needed in recirculating aquaculture systems.A long photoperiod is beneficial to largemouth bass growth.Low light intensity is beneficial to largemouth bass growth.Abstract. In this study, recirculating aquaculture systems (RAS) were used to culture juvenile largemouth bass, and the effects of LED light intensity and photoperiod on the survival and growth performance of juvenile largemouth bass were studied. In the light intensity experiment, largemouth bass juveniles with an initial weight of 0.53 ±0.02 g were subjected to a two-month feeding experiment under two different light intensities: group A, at 0.5 W m-2 in the first month and 5 W m-2 in the second month; and group B, at 5 W m-2 in the first month and 0.5 W m-2 in the second month. The results showed that in the first month of the experiment, the growth rate of fry was faster in group A than in group B. After changing the light intensity, the weight of the fry in group B after one month of growth had exceeded and was significantly higher than that in group A. Based on the above experimental results, we conducted a photoperiod experiment. Largemouth bass juveniles with an initial weight of 0.56 ±0.02 g were cultured for two months under four different photoperiods (24L:0D, 16L:8D, 8L:16D, and 0L:24D). The light intensity of the four groups was 0.5 W m-2. The fry growth rate was fastest in the 24L:0D photoperiod group and slowest in the 0L:24D photoperiod group. The growth rate of the 24L:0D photoperiod group was significantly higher than that of the 0L:24D photoperiod group (p < 0.05). The final fry weight was highest in the 24L:0D group, followed by that in the 16L:8D group and 8L:16D group, with the lowest weight observed in the 0L:24D group (p < 0.05). Although the different light conditions in the two experiments had no significant effect on the survival rate of juvenile largemouth bass (p > 0.05), a low-intensity light environment with a continuous photoperiod during the juvenile largemouth bass culture process promoted growth and development. Keywords: Growth, Largemouth bass, Light intensity, Photoperiod, RAS.
循环水养殖系统需要灯光设计。较长的光周期有利于大口黑鲈的生长。低光强有利于大口黑鲈的生长。本研究采用循环水养殖系统(RAS)对大口黑鲈幼鱼进行养殖，研究了LED光强和光周期对大口黑鲈幼鱼生存和生长性能的影响。光照强度试验中，初始体重为0.53±0.02 g的大口黑鲈幼鱼在两种不同光照强度下进行为期2个月的摄食试验:a组，第一个月0.5 W m-2，第二个月5 W m-2;B组第一个月5w - m-2，第二个月0.5 W - m-2。结果表明，在试验的第一个月，A组鱼苗的生长速度快于B组。改变光照强度后，B组鱼苗生长一个月后的体重已经超过并显著高于A组。基于上述试验结果，我们进行了光周期试验。选取初始体重为0.56±0.02 g的大口黑鲈幼鱼，在24L:0D、16L:8D、8L:16D和0L:24D四种不同光周期下培养2个月。四组光照强度均为0.5 W m-2。鱼苗生长速度以24L:0D光周期组最快，以0L:24D光周期组最慢。24L:0D光周期组的生长速率显著高于0L:24D光周期组(p < 0.05)。鱼苗末重以24L:0D组最高，16L:8D组次之，8L:16D组次之，以0L:24D组最低(p < 0.05)。虽然两个试验中不同的光照条件对大口黑鲈幼鱼的成活率没有显著影响(p < 0.05)，但在大口黑鲈幼鱼养殖过程中，持续的光周期的低强度光照环境促进了大口黑鲈幼鱼的生长发育。关键词:生长，大口黑鲈，光强，光周期，RAS。
{"title":"Effects of Light Intensity and Photoperiod on the Growth Performance of Largemouth Bass (Micropterus salmoides) in Recirculating Aquaculture Systems","authors":"L. Ye, Yadong Zhang, Jian Zhao, Xia Zhao, Jianshe Li, Zhangying Ye","doi":"10.13031/trans.14284","DOIUrl":"https://doi.org/10.13031/trans.14284","url":null,"abstract":"HighlightsLight design is needed in recirculating aquaculture systems.A long photoperiod is beneficial to largemouth bass growth.Low light intensity is beneficial to largemouth bass growth.Abstract. In this study, recirculating aquaculture systems (RAS) were used to culture juvenile largemouth bass, and the effects of LED light intensity and photoperiod on the survival and growth performance of juvenile largemouth bass were studied. In the light intensity experiment, largemouth bass juveniles with an initial weight of 0.53 ±0.02 g were subjected to a two-month feeding experiment under two different light intensities: group A, at 0.5 W m-2 in the first month and 5 W m-2 in the second month; and group B, at 5 W m-2 in the first month and 0.5 W m-2 in the second month. The results showed that in the first month of the experiment, the growth rate of fry was faster in group A than in group B. After changing the light intensity, the weight of the fry in group B after one month of growth had exceeded and was significantly higher than that in group A. Based on the above experimental results, we conducted a photoperiod experiment. Largemouth bass juveniles with an initial weight of 0.56 ±0.02 g were cultured for two months under four different photoperiods (24L:0D, 16L:8D, 8L:16D, and 0L:24D). The light intensity of the four groups was 0.5 W m-2. The fry growth rate was fastest in the 24L:0D photoperiod group and slowest in the 0L:24D photoperiod group. The growth rate of the 24L:0D photoperiod group was significantly higher than that of the 0L:24D photoperiod group (p < 0.05). The final fry weight was highest in the 24L:0D group, followed by that in the 16L:8D group and 8L:16D group, with the lowest weight observed in the 0L:24D group (p < 0.05). Although the different light conditions in the two experiments had no significant effect on the survival rate of juvenile largemouth bass (p > 0.05), a low-intensity light environment with a continuous photoperiod during the juvenile largemouth bass culture process promoted growth and development. Keywords: Growth, Largemouth bass, Light intensity, Photoperiod, RAS.","PeriodicalId":23120,"journal":{"name":"Transactions of the ASABE","volume":"6 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78434843","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
HighlightsForage rape crop could effectively alleviate the lack of green forage for livestock in winter.With the growth of forage rape crop, stem lignification was exacerbated and its palatability degenerated.The relationship between particle length and palatability was explored in a cattle feeding experiment.Optimal working parameters of the chopping device were obtained for harvesting the crop in different stages.Abstract. Forage rape crop, which uses the immature plant leaf and stem of a hybrid rape crop (Brassica napus L.) with low erucic acid and glucosinolate to feed livestock, is an innovative fresh-fed feed material with the advantages of high yield, low cost, rich nutrients, and vigorous growth in winter. In this work, a systematic study was carried out on the relationships among the characteristics of forage rape crop stems, chopping device parameters of the harvester, feeding performance, and chopped particle length (PL) in different growth stages. The results of the stem characteristics tests indicated that stem lignification occurred and increased with growth of the crop from the bolting stage to the silique stage, leading to degeneration of its palatability. The cattle feeding experiment showed that when the bolting rape crop was used, the average feed intake of the cattle fed the chopped rape crop increased by 33.35%, compared to feeding the whole crop without chopping, while the average feeding time decreased by 35.44%. Further experiments on the effects of PL after chopping on feeding performance in different growth stages showed that the optimal PL values in the bolting, flowering, and silique stages were 80, 60, and 30 mm, respectively. Finally, the corresponding cutterhead rotational speeds of the chopping device were calculated as 450, 510, and 1200 r min-1, respectively. This study provides a reference for the development and application of harvesting equipment for forage rape crop. Keywords: Agricultural mechanization, Cattle feeding, Forage palatability, Harvester, Parameter matching.
牧草油菜作物能有效缓解冬季家畜牧草缺乏的问题。随着饲用油菜的生长，茎秆木质化加剧，其适口性下降。通过牛饲试验，探讨颗粒长度与适口性的关系。针对不同收获阶段的作物，获得了斩割装置的最佳工作参数。饲用油菜作物是利用低芥酸和硫代葡萄糖苷杂交油菜(Brassica napus L.)的未成熟植物叶片和茎来喂养牲畜的一种新型新鲜饲料原料，具有产量高、成本低、营养丰富、冬季生长旺盛等优点。本文系统研究了不同生长阶段饲用油菜茎秆特性与收获机斩割装置参数、采食性能和斩粒长度之间的关系。茎秆特性试验结果表明，从抽苔期到吐丝期，茎秆发生木质化，木质化程度随着作物的生长而增加，导致其适口性退化。饲喂试验表明，采用抽油油菜作物时，采食切碎油菜作物的牛平均采食量比采食全油菜作物的牛提高了33.35%，平均采食时间减少了35.44%。进一步研究刈割对不同生育期采食性能影响的试验表明，抽苔期、开花期和拔节期的最佳采食量分别为80、60和30 mm。最后计算斩切装置对应的刀盘转速分别为450、510、1200 r min-1。本研究为饲用油菜收获设备的开发和应用提供了参考。关键词:农业机械化，牛饲养，饲料适口性，收割机，参数匹配。
{"title":"Cattle Feeding Experiment and Chopping Device Parameter Determination for Mechanized Harvesting of Forage Rape Crop","authors":"Xingyu Wan, Qingxi Liao, J. Yajun, Yitao Liao","doi":"10.13031/TRANS.14341","DOIUrl":"https://doi.org/10.13031/TRANS.14341","url":null,"abstract":"HighlightsForage rape crop could effectively alleviate the lack of green forage for livestock in winter.With the growth of forage rape crop, stem lignification was exacerbated and its palatability degenerated.The relationship between particle length and palatability was explored in a cattle feeding experiment.Optimal working parameters of the chopping device were obtained for harvesting the crop in different stages.Abstract. Forage rape crop, which uses the immature plant leaf and stem of a hybrid rape crop (Brassica napus L.) with low erucic acid and glucosinolate to feed livestock, is an innovative fresh-fed feed material with the advantages of high yield, low cost, rich nutrients, and vigorous growth in winter. In this work, a systematic study was carried out on the relationships among the characteristics of forage rape crop stems, chopping device parameters of the harvester, feeding performance, and chopped particle length (PL) in different growth stages. The results of the stem characteristics tests indicated that stem lignification occurred and increased with growth of the crop from the bolting stage to the silique stage, leading to degeneration of its palatability. The cattle feeding experiment showed that when the bolting rape crop was used, the average feed intake of the cattle fed the chopped rape crop increased by 33.35%, compared to feeding the whole crop without chopping, while the average feeding time decreased by 35.44%. Further experiments on the effects of PL after chopping on feeding performance in different growth stages showed that the optimal PL values in the bolting, flowering, and silique stages were 80, 60, and 30 mm, respectively. Finally, the corresponding cutterhead rotational speeds of the chopping device were calculated as 450, 510, and 1200 r min-1, respectively. This study provides a reference for the development and application of harvesting equipment for forage rape crop. Keywords: Agricultural mechanization, Cattle feeding, Forage palatability, Harvester, Parameter matching.","PeriodicalId":23120,"journal":{"name":"Transactions of the ASABE","volume":"48 1","pages":"715-725"},"PeriodicalIF":1.5,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74119641","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Worldwide, the use of uncrewed aerial vehicles (UAVs) for pesticide application has grown tremendously in the past decade. Their adoption has been slower for Midwestern row crops. This study compared droplet size, coverage, and drift potential of sprays from UAV application methods to those from ground (implement) sprayer methods on corn in the Midwest. Droplet sizes measured during UAV spray trials [geometric mean diameters of 179 and 112 μm for UAV (boom) and UAV (no boom), respectively] were substantially smaller than those deposited during implement spray trials [mean diameters of 303 and 423 μm for implement (regular) and implement (pulse)]. Droplet coverage was high and localized in the middle swath of the field for the UAV with boom (10 to 30 droplets cm-2) and with no boom (60 droplets cm-2). Droplet coverage was broader, covering the entire field width for the implement methods (10 to 40 droplets cm-2). Vertical coverage of droplets was more uniform for UAV methods than implement methods. Although the UAVs produced smaller droplets than the implement methods, we still observed greater potential for downwind pesticide drift during the implement spray trials. Because localized application may be beneficial for pest control and drift reduction, the findings indicate a strong potential for "spot" or "band" spray coverage using UAV methods. This is likely due to the smaller size, reduced spray volumes, and increased agility of UAVs as compared to more conventional methods.
{"title":"Comparison of Droplet Size, Coverage, and Drift Potential from UAV Application Methods and Ground Application Methods on Row Crops.","authors":"J Gibbs, T M Peters, L P Heck","doi":"10.13031/trans.14121","DOIUrl":"https://doi.org/10.13031/trans.14121","url":null,"abstract":"<p><p>Worldwide, the use of uncrewed aerial vehicles (UAVs) for pesticide application has grown tremendously in the past decade. Their adoption has been slower for Midwestern row crops. This study compared droplet size, coverage, and drift potential of sprays from UAV application methods to those from ground (implement) sprayer methods on corn in the Midwest. Droplet sizes measured during UAV spray trials [geometric mean diameters of 179 and 112 μm for UAV (boom) and UAV (no boom), respectively] were substantially smaller than those deposited during implement spray trials [mean diameters of 303 and 423 μm for implement (regular) and implement (pulse)]. Droplet coverage was high and localized in the middle swath of the field for the UAV with boom (10 to 30 droplets cm<sup>-2</sup>) and with no boom (60 droplets cm<sup>-2</sup>). Droplet coverage was broader, covering the entire field width for the implement methods (10 to 40 droplets cm<sup>-2</sup>). Vertical coverage of droplets was more uniform for UAV methods than implement methods. Although the UAVs produced smaller droplets than the implement methods, we still observed greater potential for downwind pesticide drift during the implement spray trials. Because localized application may be beneficial for pest control and drift reduction, the findings indicate a strong potential for \"spot\" or \"band\" spray coverage using UAV methods. This is likely due to the smaller size, reduced spray volumes, and increased agility of UAVs as compared to more conventional methods.</p>","PeriodicalId":23120,"journal":{"name":"Transactions of the ASABE","volume":"64 3","pages":"819-828"},"PeriodicalIF":1.5,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10476208/pdf/nihms-1926678.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10533337","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
F. Lamm, P. Colaizzi, R. Sorensen, J. Bordovsky, M. Dougherty, K. Balkcom, D. Zaccaria, K. Bali, D. Rudnick, R. Peters
HighlightsSubsurface drip irrigation (SDI) has continued to expand in irrigation area within the U.S. during the last 15 years.Research with SDI continues for multiple crop types (fiber, grain and oilseed, horticultural, forage, and turf).SDI usage on many crops has matured through research and development of appropriate strategies and technologiesDespite some persistent challenges to successful use of SDI, important opportunities exist for further adoption.Abstract. Subsurface drip irrigation (SDI) offers several advantages over alternative irrigation systems when it is designed and installed correctly and when best management practices are adopted. These advantages include the ability to apply water and nutrients directly and efficiently within the crop root zone. Disadvantages of SDI in commercial agriculture relative to alternative irrigation systems include greater capital cost per unit land area (except for small land parcels), unfamiliar management and maintenance protocols that can exacerbate the potential for emitter clogging, the visibility of system attributes (components and design characteristics) and performance, and the susceptibility to damage (i.e., rodents and tillage) of the subsurface driplines. Despite these disadvantages, SDI continues to be adopted in commercial agriculture in the U.S., and research efforts to evaluate and develop SDI systems continue as well. This article summarizes recent progress in research (2010 to 2020) and the status of commercial adoption of SDI, along with a discussion of current challenges and future opportunities. Keywords: Drip Irrigation, Irrigation, Irrigation systems, Microirrigation, SDI, Water management.
{"title":"A 2020 Vision of Subsurface Drip Irrigation in the U.S.","authors":"F. Lamm, P. Colaizzi, R. Sorensen, J. Bordovsky, M. Dougherty, K. Balkcom, D. Zaccaria, K. Bali, D. Rudnick, R. Peters","doi":"10.13031/trans.14555","DOIUrl":"https://doi.org/10.13031/trans.14555","url":null,"abstract":"HighlightsSubsurface drip irrigation (SDI) has continued to expand in irrigation area within the U.S. during the last 15 years.Research with SDI continues for multiple crop types (fiber, grain and oilseed, horticultural, forage, and turf).SDI usage on many crops has matured through research and development of appropriate strategies and technologiesDespite some persistent challenges to successful use of SDI, important opportunities exist for further adoption.Abstract. Subsurface drip irrigation (SDI) offers several advantages over alternative irrigation systems when it is designed and installed correctly and when best management practices are adopted. These advantages include the ability to apply water and nutrients directly and efficiently within the crop root zone. Disadvantages of SDI in commercial agriculture relative to alternative irrigation systems include greater capital cost per unit land area (except for small land parcels), unfamiliar management and maintenance protocols that can exacerbate the potential for emitter clogging, the visibility of system attributes (components and design characteristics) and performance, and the susceptibility to damage (i.e., rodents and tillage) of the subsurface driplines. Despite these disadvantages, SDI continues to be adopted in commercial agriculture in the U.S., and research efforts to evaluate and develop SDI systems continue as well. This article summarizes recent progress in research (2010 to 2020) and the status of commercial adoption of SDI, along with a discussion of current challenges and future opportunities. Keywords: Drip Irrigation, Irrigation, Irrigation systems, Microirrigation, SDI, Water management.","PeriodicalId":23120,"journal":{"name":"Transactions of the ASABE","volume":"13 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75399349","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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