Climate change has been documented as a major threat to current agricultural strategies.Progress in understanding the impact of climate change on crop yield is essential for agricultural climate adaptation,especially ...Climate change has been documented as a major threat to current agricultural strategies.Progress in understanding the impact of climate change on crop yield is essential for agricultural climate adaptation,especially for the Huang-Huai-Hai Plain(3H Plain)of China which is an area known to be vulnerable to global warming.In this study,the impacts of climate change on winter wheat(Triticum aestivum L.)yield between the baseline period(1981–2010)and two Representative Concentration Pathways(RCP8.5 and RCP4.5)were simulated for the short-term(2010–2039),the medium-term(2040–2069)and the long-term(2070–2099)in the 3H Plain,by considering the relative contributions of changes in temperature,solar radiation and precipitation using the DSSAT-CERES-Wheat model.Results indicated that the maximum and minimum temperatures(TMAX and TMIN),solar radiation(SRAD),and precipitation(PREP)during the winter wheat season increased under these two RCPs.Yield analysis found that wheat yield increased with the increase in SRAD,PREP and CO2 concentration,but decreased with an increase in temperature.Increasing precipitation contributes the most to the total impact,increasing wheat yield by 9.53,6.62 and 23.73%for the three terms of future climate under RCP4.5 scenario,and 11.74,16.38 and 27.78%for the three terms of future climate under RCP8.5 scenario.However,as increases in temperature bring higher evapotranspiration,which further aggravated water deficits,the supposed negative effect of increasing thermal resources decreased wheat yield by 1.92,4.08 and 5.24%for the three terms of future climate under RCP4.5 scenario,and 3.64,5.87 and 5.81%for the three terms of future climate under RCP8.5 scenario with clearly larger decreases in RCP8.5.Counterintuitively,the impacts in southern sub-regions were positive,but they were all negative in the remaining sub-regions.Our analysis demonstrated that in the 3H Plain,which is a part of the mid-high latitude region,the effects of increasing thermal resources were counteracted by the aggrav展开更多
Double radionuclide tracers of 137Cs and 210Pb were used to investigate sediment sources in the Wujia Gully, a small catchment in the Hilly Sichuam Basin in 2002. Aver-age 137Cs and 210Pb concentrations in the source ...Double radionuclide tracers of 137Cs and 210Pb were used to investigate sediment sources in the Wujia Gully, a small catchment in the Hilly Sichuam Basin in 2002. Aver-age 137Cs and 210Pb concentrations in the source soils of the steep forest slopes, gentle cultivated terraces and bare slopes were 7.15±0.40 and 162.01±3.86 Bqkg-1, 4.01±0.31 and 70.96±2.65 Bq·kg-1, and 0 and 15.12±1.22 Bq·kg-1, re-spectively, while those concentrations in the recently depos-ited sediments in the reservoir were 3.06±0.23 and 72.66±1.61 Bq·kg-1, respectively. By using the mixing model, the relative sediment contributions from steep forest slopes, gen-tle cultivated terraces and bare slopes (including channel banks) were estimated to be 18%, 46% and 36%, respec-tively. Cultivated terraces and bare slopes (including channel banks) were the first and the second important sediment sources in catchment. Specific sediment yield in the catch-ment was 642 t·km-2·a-1 from the deposited sediment volume in the reservoir since 1956. Soil erosion rates for the forest slopes and cultivated terraces, which accounted for 2/3 and 1/3 of the drainage area in the catchment, were esti-mated to be 173 and 886 t·km-2·a-1, respectively.展开更多
基金supported by the National Natural Science Foundation of China (41401510 and 41675115)the Agricultural Science and Technology Innovation Program of Chinese Academy of Agricultural Sciences (2017–2020)
文摘Climate change has been documented as a major threat to current agricultural strategies.Progress in understanding the impact of climate change on crop yield is essential for agricultural climate adaptation,especially for the Huang-Huai-Hai Plain(3H Plain)of China which is an area known to be vulnerable to global warming.In this study,the impacts of climate change on winter wheat(Triticum aestivum L.)yield between the baseline period(1981–2010)and two Representative Concentration Pathways(RCP8.5 and RCP4.5)were simulated for the short-term(2010–2039),the medium-term(2040–2069)and the long-term(2070–2099)in the 3H Plain,by considering the relative contributions of changes in temperature,solar radiation and precipitation using the DSSAT-CERES-Wheat model.Results indicated that the maximum and minimum temperatures(TMAX and TMIN),solar radiation(SRAD),and precipitation(PREP)during the winter wheat season increased under these two RCPs.Yield analysis found that wheat yield increased with the increase in SRAD,PREP and CO2 concentration,but decreased with an increase in temperature.Increasing precipitation contributes the most to the total impact,increasing wheat yield by 9.53,6.62 and 23.73%for the three terms of future climate under RCP4.5 scenario,and 11.74,16.38 and 27.78%for the three terms of future climate under RCP8.5 scenario.However,as increases in temperature bring higher evapotranspiration,which further aggravated water deficits,the supposed negative effect of increasing thermal resources decreased wheat yield by 1.92,4.08 and 5.24%for the three terms of future climate under RCP4.5 scenario,and 3.64,5.87 and 5.81%for the three terms of future climate under RCP8.5 scenario with clearly larger decreases in RCP8.5.Counterintuitively,the impacts in southern sub-regions were positive,but they were all negative in the remaining sub-regions.Our analysis demonstrated that in the 3H Plain,which is a part of the mid-high latitude region,the effects of increasing thermal resources were counteracted by the aggrav
文摘Double radionuclide tracers of 137Cs and 210Pb were used to investigate sediment sources in the Wujia Gully, a small catchment in the Hilly Sichuam Basin in 2002. Aver-age 137Cs and 210Pb concentrations in the source soils of the steep forest slopes, gentle cultivated terraces and bare slopes were 7.15±0.40 and 162.01±3.86 Bqkg-1, 4.01±0.31 and 70.96±2.65 Bq·kg-1, and 0 and 15.12±1.22 Bq·kg-1, re-spectively, while those concentrations in the recently depos-ited sediments in the reservoir were 3.06±0.23 and 72.66±1.61 Bq·kg-1, respectively. By using the mixing model, the relative sediment contributions from steep forest slopes, gen-tle cultivated terraces and bare slopes (including channel banks) were estimated to be 18%, 46% and 36%, respec-tively. Cultivated terraces and bare slopes (including channel banks) were the first and the second important sediment sources in catchment. Specific sediment yield in the catch-ment was 642 t·km-2·a-1 from the deposited sediment volume in the reservoir since 1956. Soil erosion rates for the forest slopes and cultivated terraces, which accounted for 2/3 and 1/3 of the drainage area in the catchment, were esti-mated to be 173 and 886 t·km-2·a-1, respectively.
