Projected changes in weather parameters, mainly temperature and rainfall, have already started to show their effect on agricultural production. To cope with the changing scenarios, adoption of appropriate management s...Projected changes in weather parameters, mainly temperature and rainfall, have already started to show their effect on agricultural production. To cope with the changing scenarios, adoption of appropriate management strategies is of paramount importance. A study was undertaken to evaluate the most appropriate combination of sowing date and phosphorus fertilization level for peanut crops grown in sandy loam soil in a subhumid region of eastern India. Field experiments were conducted during the summer seasons of 2012 and 2013 on peanut crops at the farm of the Indian Institute of Technology, Kharagpur. The DSSAT v4.5 CROPGRO-Peanut model was used to predict the phenology, growth, and yield of peanut crop under combinations of four sowing dates and four phosphorus fertilization levels. The model was calibrated with a 2012 dataset of growth, phenology, and yield parameters for estimating the genetic coefficients of cultivar TMV-2 and was validated with a 2013 dataset of the same parameters. Simulations of pod yield and other yield parameters using the calibrated model were found to be quite accurate. The model was able to reasonably simulate pod yield and final biomass with low normalized root mean square error (RMSE_n), low absolute root mean square error (RMSE_a) and high coefficient of determination (R^2> 0.7) over a wide range of sowing dates and different phosphorus fertilization levels sensitivity analysis indicated that sowing from the second week of January to the end of February with 30–50 kg P_2O_5 ha^(-1)would give the highest pod yield.展开更多
Estimation of soil erosion is of paramount importance due to its serious environmental and societal concern.Soil erosion would have impact on fertility of agricultural land and quality of water.The major objective of ...Estimation of soil erosion is of paramount importance due to its serious environmental and societal concern.Soil erosion would have impact on fertility of agricultural land and quality of water.The major objective of this study was to investigate the spatial heterogeneity of annual soil erosion on the grid-cell basis in a small agricultural watershed of eastern India.The study watershed has a drainage area of 973 ha and is subdivided into three sub-watersheds namely:KGSW1,KGSW2 and KGSW3,based on the land topography and drainage network.Average annual soil erosion was estimated on 100 m×100 m grid-cells by integrating universal soil loss equation(USLE)model with GIS for subsequent identification of critical erosion prone areas.It was found that 82.63%area of the total watershed falls under slight-erosion-class(0–5 t-ha^(−1)-yr^(−1)),6.87%area lies under the moderate-erosion-class(5–10 t-ha^(−1)-yr^(−1)),5.96%area is under high-erosion-class(10–20 t-ha^(−1)-yr^(−1)),3.3%area of watershed lies under the very-high-erosion-class(20–40 t-ha^(−1)-yr^(−1))and 1.24%area falls under“severe-erosion-class”(40–80 t-ha^(−1)-yr^(−1)).The study revealed that the sub-watershed KGSW3 is critical due to the presence of the highest number of critical erosion prone grid-cells.The sediment delivery ratio(SDR)was also estimated to analyze the contribution of sediment yield at the sub-watershed level.Lowest SDR for the whole watershed as compared to sub-watersheds indicates that most of the eroded soil got deposited in rice crop check-basins before reaching the outlet.The reported results can be used for prioritizing critical erosion prone areas and for determining appropriate soil erosion prevention and control measures.展开更多
基金The authors are thankful to the Agricultural and Food Engineering Department of the Indian Institute of Technology Kharagpur, India for providing facilities to conduct experiments.The authors acknowledge the India Meteorological Department, India for installing an automatic weather stationat the institute.
文摘Projected changes in weather parameters, mainly temperature and rainfall, have already started to show their effect on agricultural production. To cope with the changing scenarios, adoption of appropriate management strategies is of paramount importance. A study was undertaken to evaluate the most appropriate combination of sowing date and phosphorus fertilization level for peanut crops grown in sandy loam soil in a subhumid region of eastern India. Field experiments were conducted during the summer seasons of 2012 and 2013 on peanut crops at the farm of the Indian Institute of Technology, Kharagpur. The DSSAT v4.5 CROPGRO-Peanut model was used to predict the phenology, growth, and yield of peanut crop under combinations of four sowing dates and four phosphorus fertilization levels. The model was calibrated with a 2012 dataset of growth, phenology, and yield parameters for estimating the genetic coefficients of cultivar TMV-2 and was validated with a 2013 dataset of the same parameters. Simulations of pod yield and other yield parameters using the calibrated model were found to be quite accurate. The model was able to reasonably simulate pod yield and final biomass with low normalized root mean square error (RMSE_n), low absolute root mean square error (RMSE_a) and high coefficient of determination (R^2> 0.7) over a wide range of sowing dates and different phosphorus fertilization levels sensitivity analysis indicated that sowing from the second week of January to the end of February with 30–50 kg P_2O_5 ha^(-1)would give the highest pod yield.
文摘Estimation of soil erosion is of paramount importance due to its serious environmental and societal concern.Soil erosion would have impact on fertility of agricultural land and quality of water.The major objective of this study was to investigate the spatial heterogeneity of annual soil erosion on the grid-cell basis in a small agricultural watershed of eastern India.The study watershed has a drainage area of 973 ha and is subdivided into three sub-watersheds namely:KGSW1,KGSW2 and KGSW3,based on the land topography and drainage network.Average annual soil erosion was estimated on 100 m×100 m grid-cells by integrating universal soil loss equation(USLE)model with GIS for subsequent identification of critical erosion prone areas.It was found that 82.63%area of the total watershed falls under slight-erosion-class(0–5 t-ha^(−1)-yr^(−1)),6.87%area lies under the moderate-erosion-class(5–10 t-ha^(−1)-yr^(−1)),5.96%area is under high-erosion-class(10–20 t-ha^(−1)-yr^(−1)),3.3%area of watershed lies under the very-high-erosion-class(20–40 t-ha^(−1)-yr^(−1))and 1.24%area falls under“severe-erosion-class”(40–80 t-ha^(−1)-yr^(−1)).The study revealed that the sub-watershed KGSW3 is critical due to the presence of the highest number of critical erosion prone grid-cells.The sediment delivery ratio(SDR)was also estimated to analyze the contribution of sediment yield at the sub-watershed level.Lowest SDR for the whole watershed as compared to sub-watersheds indicates that most of the eroded soil got deposited in rice crop check-basins before reaching the outlet.The reported results can be used for prioritizing critical erosion prone areas and for determining appropriate soil erosion prevention and control measures.