Agricultural drought is a type of natural disaster that seriously impacts food security.Because the relationships among short-term rainfall,soil moisture,and crop growth are complex,accurate identification of a drough...Agricultural drought is a type of natural disaster that seriously impacts food security.Because the relationships among short-term rainfall,soil moisture,and crop growth are complex,accurate identification of a drought situation is difficult.In this study,using a conceptual model based on the relationship between water deficit and crop yield reduction,we evaluated the drought process in a typical rainfed agricultural region,Hailar county in Inner Mongolia autonomous region,China.To quantify drought,we used the precipitation-based Standardized Precipitation Index(SPI),the soil moisture-based Crop Moisture Index(CMI),as well as the Normalized Difference Vegetation Index(NDVI).Correlation analysis was conducted to examine the relationships between dekad-scale drought indices during the growing season(May–September)and final yield,according to data collection from 2000 to 2010.The results show that crop yield has positive relationships with CMI from mid-June to mid-July and with the NDVI anomaly throughout July,but no correlation with SPI.Further analysis of the relationship between the two drought indices shows that the NDVI anomaly responds to CMI with a lag of 1 dekad,particularly in July.To examine the feasibility of employing these indices for monitoring the drought process at a dekad time scale,a detailed drought assessment was carried out for selected drought years.The results confirm that the soil moisture-based vegetation indices in the late vegetative to early reproductive growth stages can be used to detect agricultural drought in the study area.Therefore,the framework of the conceptual model developed for drought monitoring can be employed to support drought mitigation in the rainfed agricultural region of Northern China.展开更多
To help farmers in the mid hills of Nepal improve their crop management and rice yields, we conducted a study testing different nursery management options and their effect on grain yield and yield components under rai...To help farmers in the mid hills of Nepal improve their crop management and rice yields, we conducted a study testing different nursery management options and their effect on grain yield and yield components under rainfed conditions. The experiment was conducted in a farmer’s field during the cropping season 2009 and 2010 at Sundarbazar, Lamjung, Nepal, using a 3-factor factorial RCB design with 3 replications. The three management factors tested were 1) fertilizer management in the nursery, 2) seeding density, and 3) seedling age at transplanting, using the rainfed lowland rice variety Radha-4. There were eight treatment combinations, consisting of two levels of fertilization (0 and 20:20:0:13 kg NPKS ha-1 at 15 DAS), two levels of seeding density (607 and 303 g·m-2) and two seedling ages (20 and 40 days old). Two years’ results showed that top-dressed fertilizer in the nursery had no consistent effect on grain yield. However, lower seeding density (303 g·m-2) resulted in taller plants, more productive tillers m-2, less sterility and higher grain yield. In addition, older seedlings (40 days) produced taller plants, more productive tillers, more filled grains, and a higher grain and straw yield. The interaction analysis between both factors indicated that 40 days old seedling with a low seeding density produced the highest grain yield, both in the drought season 2009 and the high-yielding season 2010. The economic analysis confirmed that the treatment with low seeding density and 40 days old seedlings produced by far the highest net returns and B:C ratio in both seasons, independent of the fertilizer treatment. The combination of these two management components is therefore economically viable and profitable, and can be recommended to farmers. However, the results need to be confirmed for other varieties used by farmers in the region.展开更多
More than 80%of plants form mutualistic symbiotic relationships with arbuscular mycorrhizal fungi(AMF),and the application of fertilizers,such as nitrogen(N)and phosphorus(P)fertilizers,is a common agricultural manage...More than 80%of plants form mutualistic symbiotic relationships with arbuscular mycorrhizal fungi(AMF),and the application of fertilizers,such as nitrogen(N)and phosphorus(P)fertilizers,is a common agricultural management practice to improve crop yield and quality.However,the potential effects of long-term N and P fertilization on the AMF community in the rainfed agricultural system of the Loess Plateau of China are still not well understood.In this study,a long-term field experiment was conducted based on orthogonal design,with three N levels(0,90,and 180 kg ha^(-1)year^(-1))and three P levels(0,90,and 180 kg ha^(-1)year^(-1))for wheat fertilization.Changes in AMF community and correlations between AMF community composition,soil environmental factors,and wheat yield component traits were analyzed using traditional biochemical methods and high-throughput sequencing technology.The results showed that long-term N and P addition had a significant effect on the AMF community structure and composition.Nitrogen application alone significantly reduced the richness and diversity of AMF community,whereas the combined application of N and P significantly increased the richness and diversity of AMF community.The AMF community was driven mainly by soil available P,total P,and pH.There was a significant positive correlation between Glomus abundance and wheat yield and a significant negative correlation between Paraglomus abundance and wheat yield.Long-term N and P addition directly increased crop yield and affected yield indirectly by influencing soil chemical properties and the AMF community.Combined application of N and P both at90 kg ha^(-1)year^(-1)could improve the ecological and physiological functions of the AMF community and benefit the sustainable development of rainfed agriculture.展开更多
Improving agricultural water productivity, under rainfed or irrigated conditions, holds significant scope for addressing climate change vulnerability. It also offers adaptation capacity needs as well as water and food...Improving agricultural water productivity, under rainfed or irrigated conditions, holds significant scope for addressing climate change vulnerability. It also offers adaptation capacity needs as well as water and food security in the southern African region. In this study, evidence for climate change impacts and adaptation strategies in rainfed agricultural systems is explored through modeling predictions of crop yield, soil moisture and excess water for potential harvesting. The study specifically presents the results of climate change impacts under rainfed conditions for maize, sorghum and sunflower using soil-water-crop model simulations, integrated based on daily inputs of rainfall and evapotranspiration disaggregated from GCM scenarios. The research targets a vast farming region dominated by heavy clay soils where rainfed agriculture is a dominant practice. The potential for improving soil water productivity and improved water harvesting have been explored as ways of climate change mitigation and adaptation measures. This can be utilized to explore and design appropriate conservation agriculture and adaptation practices in similar agro-ecological environments, and create opportunities for outscaling for much wider areas. The results of this study can suggest the need for possible policy refinements towards reducing vulnerability and adaptation to climate change in rainfed farming systems.展开更多
The components and contents of high-molecular-weight glutenin subunits(HMW-GS) in wheat grains affect glutenin macropolymer(GMP) size, which is considered an important flour quality trait in wheat. Four wheat cultivar...The components and contents of high-molecular-weight glutenin subunits(HMW-GS) in wheat grains affect glutenin macropolymer(GMP) size, which is considered an important flour quality trait in wheat. Four wheat cultivars(Shiluan 02-1, Yannong 24, Jinan 17 and Lumai 21) with different end-use qualities were used to investigate the HMW-GS and GMP contents, and the GMP particle distributions in grain produced under irrigated and rainfed conditions. The percent volume of GMP particles and the contents of HMW-GS and GMP were affected by genotype and soil water. Genotype × soil water interaction was significant only for GMP particles <12 μm and >100 μm in the growing season of 2010–2011. Irrigated and rainfed conditions had different influences on the GMP particle distribution in the four cultivars. Compared to irrigated treatment, the rainfed treatment had higher accumulations of HMW-GS and GMP, especially in cultivars Yannong 24, Jinan 17 and Lumai 21. Rainfed conditions also increased the proportion of large size particles of GMP, indicating that different water regimes had an effect on grain quality. According to correlation coefficients(r), the contents of HMW-GS and GMP in grains were negatively correlated with the volume of <12 μm GMP particles, but positively correlated with GMP particles >100 μm.展开更多
Yield loss due to low precipitation use efficiency(PUE)occurs frequently in dryland crop production.PUE is determined by a complicated process of precipitation use in farmland,which includes several sequential steps:p...Yield loss due to low precipitation use efficiency(PUE)occurs frequently in dryland crop production.PUE is determined by a complicated process of precipitation use in farmland,which includes several sequential steps:precipitation infiltrates into the soil,the infiltrated precipitation is stored in soil,the soil-stored precipitation is consumed through transpiration or evaporation,transpired precipitation is used to produce dry-matter,and finally dry-matter is re-allocated to grains.These steps can be quantified by six ratios:precipitation infiltration ratio(SW/SWe;SW,total available water;SWe,available soil water storage at the end of a specific period),precipitation storage ratio(SWe/P;P,effective precipitation),precipitation consumption ratio(ET/SW;ET,evapotranspiration),ratio of crop transpiration to evapotranspiration(T/ET;T,crop transpiration),transpiration efficiency(B/T;B,the increment of shoot biomass)and harvest index(Y/B;Y,grain yield).The final efficiency is then calculated as:PUE=SWe/P×SW/SWe×ET/SW×T/ET×B/T×Y/B.Quantifying each of those ratios is crucial for the planning and execution of PUE improvements and for optimizing the corresponding agronomic practices in a specific agricultural system.In this study,those ratios were quantified and evaluated under four integrated agronomic management systems.Our study revealed that PUE and wheat yield were significantly increased by 8–31%under manure(MIS)or biochar(BIS)integrated systems compared to either conventional farmers’(CF)or high N(HN)integrated systems.In the infiltration and storage steps,MIS and BIS resulted in lower SWe/P but higher SW/SWe compared with CF and HN.Regarding the consumption step,the annual ET/SW under MIS and BIS did not increase due to the higher ET after regreening and the lower ET before regreening compared with CF or HN.The T/ET was significantly higher under MIS and BIS than under CF or HN.In the last two steps,transpiration efficiency and harvest index were less strongly affected by the agronomic management system,alt展开更多
Background:Despite high nutritional and economic value,alfalfa yield has not been improved in the United States.Soil moisture critically influences alfalfa's yield and quality,affecting its physiological processes...Background:Despite high nutritional and economic value,alfalfa yield has not been improved in the United States.Soil moisture critically influences alfalfa's yield and quality,affecting its physiological processes,nutrient uptake,and stand growth.Additionally,the maturity stage at harvest can significantly impact both hay yield and quality.Thus,this study aimed to assess the effect of different soil moisture levels and harvesting times on forage yield,nutritive value,and the overall profitability of commercially cultivated alfalfa.Methods:Two conventional and three lower-lignin alfalfa varieties were planted in a randomized complete block with split plot design under drought,rainfed,and irrigation conditions in 2020 in Manhattan,Kansas,USA.The dry matter yield(DMY)and forage nutritive value were evaluated at late bud,early flowering,and 7 days after early flowering stages,respectively.Results:DMY varied with production year,soil water availability,and growth stages,with drought conditions causing a decline in DMY of 5%to 38%in the second production year.Water conditions and maturity stages influenced crude protein(CP)and in vitro dry matter digestibility(IVDMD).Higher soil moisture and advancing maturity stages negatively impacted CP,IVDMD,and relative forage quality.The study revealed net profit margins of 62%,64%,and 52%for drought-prone,rainfed,and irrigated production,respectively.Conclusions:Harvest timing and irrigation practices were found to have substantial implications for forage yield and nutritive value of alfalfa.The yield-quality trade-off differed under drought and irrigation,with early harvesting leading to lower yields but higher protein content and digestibility.The study findings provide potential guidance for improving alfalfa hay yield,quality,and profitability.展开更多
Potato is one of the staple food crops in North China.However,potato production in this region is threatened by the low amount and high spatial-temporal variation of precipitation.Increasing yield and water use effici...Potato is one of the staple food crops in North China.However,potato production in this region is threatened by the low amount and high spatial-temporal variation of precipitation.Increasing yield and water use efficiency(WUE)of potato by various water management practices under water resource limitation is of great importance for ensuring food security in China.However,the contributions of different water management practices to yield and WUE of potato have been rarely investigated across North China’s potato planting region.Based on meta-analysis of field experiments from the literature and model simulation,this study quantified the potential yields of potatoes without water and fertilizer limitation,and yield under irrigated and rainfed conditions,and the corresponding WUEs across four potato planting regions including the Da Hinggan Mountains(DH),the Foothills of Yanshan hilly(YH),the North foot of the Yinshan Mountains(YM),and the Loess Plateau(LP)in North China.Simulated average potential potato tuber dry weight yield by the APSIM-Potato Model was 12.4 t ha^(–1)for the YH region,11.4 t ha^(–1)for the YM region,11.2 t ha^(–1)for the DH region,and 10.7 t ha^(–1)for the LP region,respectively.Observed rainfed potato tuber dry weight yield accounted for 61,30,28 and 24%of the potential yield in the DH,YH,YM,and LP regions.The maximum WUE of 2.2 kg m^(–3)in the YH region,2.1 kg m^(–3)in the DH region,1.9 kg m^(–3)in the YM region and 1.9 kg m^(–3)in the LP region was achieved under the potential yield level.Ridge-furrow planting could boost yield by 8–49%and WUE by 2–36%while ridge-furrow planting with film mulching could boost yield by 35–89%and WUE by 7–57%across North China.Our study demonstrates that there is a large potential to increase yield and WUE simultaneously by combining ridge-furrow planting with film mulching and supplemental irrigation in different potato planting regions with limited water resources.展开更多
Several studies have reported a significant yearly decrease in forest cover globally, using satellite images. This is especially true in West Africa, where rapid urbanisation acerbates the problem, and both of these c...Several studies have reported a significant yearly decrease in forest cover globally, using satellite images. This is especially true in West Africa, where rapid urbanisation acerbates the problem, and both of these changes lead to alterations in rainfall regime and other changes in climatic parameters. Several studies reveal that adaptation which reduces vulnerability to adverse climatic variation effects is the key to developing resilience against climate change. In this region, over 90% of farmers are engaged in small-scale rainfed crop cultivation and rely on their own weather perception, instincts and what they observe from the surrounding biota (flora and fauna) to forecast the weather and plan their agricultural activities. The pressing nature of the problem of climate variability in Africa had provoked a lot of research into developing and testing several adaptation strategies to control the situation. Various strategies to improve and localize global, regional and national climate services (Local Forecast, Scientific Forecast and Integrated Forecast) needed by the farmers are being developed to build resilience against climate change. This review illustrates the situation in Ghana and identifies various forecast strategies developed to mitigate the adverse effects of climate variability on agricultural productivity. These mitigation methods include the development of climate services to provide users with forecast information in order to make climate-smart decisions to minimize the risk.展开更多
Based on the soil moisture data from the locating experiments from 1986—1990, and using the water balance method, the water supply and demand state in the field of winter wheat, and the ways for improving water cond...Based on the soil moisture data from the locating experiments from 1986—1990, and using the water balance method, the water supply and demand state in the field of winter wheat, and the ways for improving water condition in dryland of dry subhumid area of the Loess Plateau were studied. The results suggested that a low precipitation satisfying ratio of 42.9%—58.8% appears in the growing period of winter wheat, and the yield, to a great extent depended on the water that was stored in deep soil layer in the previous rainy season. The filed trial results showed that tillage in the summer fallow period,straw cover, soil moisture regulation with adequate fertilization, crop rotation and proper cropping system could be the efficient ways for improving the water condition,and for the exploitation and utilization of natural water resources(both precipitation and soil water) in the winter wheat field of dryland. 展开更多
Reduced tillage provides ecological and economic benefits to arable land on the Loess Plateau of China, where soil erosion has long been a serious problem and soil water availability is largely restricted. However, hi...Reduced tillage provides ecological and economic benefits to arable land on the Loess Plateau of China, where soil erosion has long been a serious problem and soil water availability is largely restricted. However, high abundances of weeds in reduced tillage systems cause significant yield losses. In this study, we explored the effects of no-tillage and stubble retention on the number and density of weeds and weed seeds in a 12-year maize-winter wheat-common vetch rotation on the Loess Plateau. Four treatments including conventional tillage, no-tillage, conventional tillage＋stubble retention and no-tillage＋stubble retention were designed and applied. We found that no-tillage increased the number of weed species and weed density in most of the crops, while stubble retention decreased weed density in maize and tended to suppress weeds in both no-tillage treatments（no-tillage and no-tillage＋stubble retention）. No-tillage led to an increase in the number of weed species in the weed seedbank and tended to increase seed density during the spring growth of winter wheat, but it decreased seed density during post-vetch fallow. Stubble retention tended to reduce seed density during the spring growth of winter wheat and post-vetch fallow. We concluded that no-tillage can promote weeds in the experimental crop rotation, while stubble retention suppresses weeds in untilled fields. The combined effects of stubble retention and no-tillage on weed suppression varied among the three crops. Based on these results, we recommend stubble retention in untilled legume-crop rotations on the Loess Plateau to improve the control of weeds.展开更多
基金supported by the Global Center of Excellence Project for Dryland Science of the Ministry of Education,Culture,Sports,Science and Technology of Japan
文摘Agricultural drought is a type of natural disaster that seriously impacts food security.Because the relationships among short-term rainfall,soil moisture,and crop growth are complex,accurate identification of a drought situation is difficult.In this study,using a conceptual model based on the relationship between water deficit and crop yield reduction,we evaluated the drought process in a typical rainfed agricultural region,Hailar county in Inner Mongolia autonomous region,China.To quantify drought,we used the precipitation-based Standardized Precipitation Index(SPI),the soil moisture-based Crop Moisture Index(CMI),as well as the Normalized Difference Vegetation Index(NDVI).Correlation analysis was conducted to examine the relationships between dekad-scale drought indices during the growing season(May–September)and final yield,according to data collection from 2000 to 2010.The results show that crop yield has positive relationships with CMI from mid-June to mid-July and with the NDVI anomaly throughout July,but no correlation with SPI.Further analysis of the relationship between the two drought indices shows that the NDVI anomaly responds to CMI with a lag of 1 dekad,particularly in July.To examine the feasibility of employing these indices for monitoring the drought process at a dekad time scale,a detailed drought assessment was carried out for selected drought years.The results confirm that the soil moisture-based vegetation indices in the late vegetative to early reproductive growth stages can be used to detect agricultural drought in the study area.Therefore,the framework of the conceptual model developed for drought monitoring can be employed to support drought mitigation in the rainfed agricultural region of Northern China.
文摘To help farmers in the mid hills of Nepal improve their crop management and rice yields, we conducted a study testing different nursery management options and their effect on grain yield and yield components under rainfed conditions. The experiment was conducted in a farmer’s field during the cropping season 2009 and 2010 at Sundarbazar, Lamjung, Nepal, using a 3-factor factorial RCB design with 3 replications. The three management factors tested were 1) fertilizer management in the nursery, 2) seeding density, and 3) seedling age at transplanting, using the rainfed lowland rice variety Radha-4. There were eight treatment combinations, consisting of two levels of fertilization (0 and 20:20:0:13 kg NPKS ha-1 at 15 DAS), two levels of seeding density (607 and 303 g·m-2) and two seedling ages (20 and 40 days old). Two years’ results showed that top-dressed fertilizer in the nursery had no consistent effect on grain yield. However, lower seeding density (303 g·m-2) resulted in taller plants, more productive tillers m-2, less sterility and higher grain yield. In addition, older seedlings (40 days) produced taller plants, more productive tillers, more filled grains, and a higher grain and straw yield. The interaction analysis between both factors indicated that 40 days old seedling with a low seeding density produced the highest grain yield, both in the drought season 2009 and the high-yielding season 2010. The economic analysis confirmed that the treatment with low seeding density and 40 days old seedlings produced by far the highest net returns and B:C ratio in both seasons, independent of the fertilizer treatment. The combination of these two management components is therefore economically viable and profitable, and can be recommended to farmers. However, the results need to be confirmed for other varieties used by farmers in the region.
基金jointly funded by a project of the Science and Technology Department of Shaanxi Province,China(No.2022NY-074)the National Natural Science Foundation of China(Nos.41501255 and 41671269)+1 种基金Xi’an Science and Technology Project,China(No.21NYYF0033)the Fundamental Research Funds for the Central Universities,China(No.SYJS202224)。
文摘More than 80%of plants form mutualistic symbiotic relationships with arbuscular mycorrhizal fungi(AMF),and the application of fertilizers,such as nitrogen(N)and phosphorus(P)fertilizers,is a common agricultural management practice to improve crop yield and quality.However,the potential effects of long-term N and P fertilization on the AMF community in the rainfed agricultural system of the Loess Plateau of China are still not well understood.In this study,a long-term field experiment was conducted based on orthogonal design,with three N levels(0,90,and 180 kg ha^(-1)year^(-1))and three P levels(0,90,and 180 kg ha^(-1)year^(-1))for wheat fertilization.Changes in AMF community and correlations between AMF community composition,soil environmental factors,and wheat yield component traits were analyzed using traditional biochemical methods and high-throughput sequencing technology.The results showed that long-term N and P addition had a significant effect on the AMF community structure and composition.Nitrogen application alone significantly reduced the richness and diversity of AMF community,whereas the combined application of N and P significantly increased the richness and diversity of AMF community.The AMF community was driven mainly by soil available P,total P,and pH.There was a significant positive correlation between Glomus abundance and wheat yield and a significant negative correlation between Paraglomus abundance and wheat yield.Long-term N and P addition directly increased crop yield and affected yield indirectly by influencing soil chemical properties and the AMF community.Combined application of N and P both at90 kg ha^(-1)year^(-1)could improve the ecological and physiological functions of the AMF community and benefit the sustainable development of rainfed agriculture.
文摘Improving agricultural water productivity, under rainfed or irrigated conditions, holds significant scope for addressing climate change vulnerability. It also offers adaptation capacity needs as well as water and food security in the southern African region. In this study, evidence for climate change impacts and adaptation strategies in rainfed agricultural systems is explored through modeling predictions of crop yield, soil moisture and excess water for potential harvesting. The study specifically presents the results of climate change impacts under rainfed conditions for maize, sorghum and sunflower using soil-water-crop model simulations, integrated based on daily inputs of rainfall and evapotranspiration disaggregated from GCM scenarios. The research targets a vast farming region dominated by heavy clay soils where rainfed agriculture is a dominant practice. The potential for improving soil water productivity and improved water harvesting have been explored as ways of climate change mitigation and adaptation measures. This can be utilized to explore and design appropriate conservation agriculture and adaptation practices in similar agro-ecological environments, and create opportunities for outscaling for much wider areas. The results of this study can suggest the need for possible policy refinements towards reducing vulnerability and adaptation to climate change in rainfed farming systems.
基金supported by the National Natural Science Foundation of China (Grant No. 31271667)the Natural Science Foundation of Shandong Province, China (Grant No. ZR2010CM044)+1 种基金the National Basic Research Program of China (973 Program, Grant No. 2009CB118602)State Key Laboratory of Crop Biology (Grant No. 2012KF01) of Shandong Agricultural University, Tai'an, Shandong, China
文摘The components and contents of high-molecular-weight glutenin subunits(HMW-GS) in wheat grains affect glutenin macropolymer(GMP) size, which is considered an important flour quality trait in wheat. Four wheat cultivars(Shiluan 02-1, Yannong 24, Jinan 17 and Lumai 21) with different end-use qualities were used to investigate the HMW-GS and GMP contents, and the GMP particle distributions in grain produced under irrigated and rainfed conditions. The percent volume of GMP particles and the contents of HMW-GS and GMP were affected by genotype and soil water. Genotype × soil water interaction was significant only for GMP particles <12 μm and >100 μm in the growing season of 2010–2011. Irrigated and rainfed conditions had different influences on the GMP particle distribution in the four cultivars. Compared to irrigated treatment, the rainfed treatment had higher accumulations of HMW-GS and GMP, especially in cultivars Yannong 24, Jinan 17 and Lumai 21. Rainfed conditions also increased the proportion of large size particles of GMP, indicating that different water regimes had an effect on grain quality. According to correlation coefficients(r), the contents of HMW-GS and GMP in grains were negatively correlated with the volume of <12 μm GMP particles, but positively correlated with GMP particles >100 μm.
基金support of the National Key Research and Development Program of China(2021YFD1900705)the National Basic Research Program of China(2015CB150402)the National Key Technology R&D Program of China(2015BAD22B01).
文摘Yield loss due to low precipitation use efficiency(PUE)occurs frequently in dryland crop production.PUE is determined by a complicated process of precipitation use in farmland,which includes several sequential steps:precipitation infiltrates into the soil,the infiltrated precipitation is stored in soil,the soil-stored precipitation is consumed through transpiration or evaporation,transpired precipitation is used to produce dry-matter,and finally dry-matter is re-allocated to grains.These steps can be quantified by six ratios:precipitation infiltration ratio(SW/SWe;SW,total available water;SWe,available soil water storage at the end of a specific period),precipitation storage ratio(SWe/P;P,effective precipitation),precipitation consumption ratio(ET/SW;ET,evapotranspiration),ratio of crop transpiration to evapotranspiration(T/ET;T,crop transpiration),transpiration efficiency(B/T;B,the increment of shoot biomass)and harvest index(Y/B;Y,grain yield).The final efficiency is then calculated as:PUE=SWe/P×SW/SWe×ET/SW×T/ET×B/T×Y/B.Quantifying each of those ratios is crucial for the planning and execution of PUE improvements and for optimizing the corresponding agronomic practices in a specific agricultural system.In this study,those ratios were quantified and evaluated under four integrated agronomic management systems.Our study revealed that PUE and wheat yield were significantly increased by 8–31%under manure(MIS)or biochar(BIS)integrated systems compared to either conventional farmers’(CF)or high N(HN)integrated systems.In the infiltration and storage steps,MIS and BIS resulted in lower SWe/P but higher SW/SWe compared with CF and HN.Regarding the consumption step,the annual ET/SW under MIS and BIS did not increase due to the higher ET after regreening and the lower ET before regreening compared with CF or HN.The T/ET was significantly higher under MIS and BIS than under CF or HN.In the last two steps,transpiration efficiency and harvest index were less strongly affected by the agronomic management system,alt
基金US Department of Agriculture,National Institute of Food and Agriculture,Grant/Award Number:2019-70005-30238。
文摘Background:Despite high nutritional and economic value,alfalfa yield has not been improved in the United States.Soil moisture critically influences alfalfa's yield and quality,affecting its physiological processes,nutrient uptake,and stand growth.Additionally,the maturity stage at harvest can significantly impact both hay yield and quality.Thus,this study aimed to assess the effect of different soil moisture levels and harvesting times on forage yield,nutritive value,and the overall profitability of commercially cultivated alfalfa.Methods:Two conventional and three lower-lignin alfalfa varieties were planted in a randomized complete block with split plot design under drought,rainfed,and irrigation conditions in 2020 in Manhattan,Kansas,USA.The dry matter yield(DMY)and forage nutritive value were evaluated at late bud,early flowering,and 7 days after early flowering stages,respectively.Results:DMY varied with production year,soil water availability,and growth stages,with drought conditions causing a decline in DMY of 5%to 38%in the second production year.Water conditions and maturity stages influenced crude protein(CP)and in vitro dry matter digestibility(IVDMD).Higher soil moisture and advancing maturity stages negatively impacted CP,IVDMD,and relative forage quality.The study revealed net profit margins of 62%,64%,and 52%for drought-prone,rainfed,and irrigated production,respectively.Conclusions:Harvest timing and irrigation practices were found to have substantial implications for forage yield and nutritive value of alfalfa.The yield-quality trade-off differed under drought and irrigation,with early harvesting leading to lower yields but higher protein content and digestibility.The study findings provide potential guidance for improving alfalfa hay yield,quality,and profitability.
基金the National Key Research and Development Program of China(2021YFD1901104)the 2115 Talent Development Program of China Agricultural University(00109016)。
文摘Potato is one of the staple food crops in North China.However,potato production in this region is threatened by the low amount and high spatial-temporal variation of precipitation.Increasing yield and water use efficiency(WUE)of potato by various water management practices under water resource limitation is of great importance for ensuring food security in China.However,the contributions of different water management practices to yield and WUE of potato have been rarely investigated across North China’s potato planting region.Based on meta-analysis of field experiments from the literature and model simulation,this study quantified the potential yields of potatoes without water and fertilizer limitation,and yield under irrigated and rainfed conditions,and the corresponding WUEs across four potato planting regions including the Da Hinggan Mountains(DH),the Foothills of Yanshan hilly(YH),the North foot of the Yinshan Mountains(YM),and the Loess Plateau(LP)in North China.Simulated average potential potato tuber dry weight yield by the APSIM-Potato Model was 12.4 t ha^(–1)for the YH region,11.4 t ha^(–1)for the YM region,11.2 t ha^(–1)for the DH region,and 10.7 t ha^(–1)for the LP region,respectively.Observed rainfed potato tuber dry weight yield accounted for 61,30,28 and 24%of the potential yield in the DH,YH,YM,and LP regions.The maximum WUE of 2.2 kg m^(–3)in the YH region,2.1 kg m^(–3)in the DH region,1.9 kg m^(–3)in the YM region and 1.9 kg m^(–3)in the LP region was achieved under the potential yield level.Ridge-furrow planting could boost yield by 8–49%and WUE by 2–36%while ridge-furrow planting with film mulching could boost yield by 35–89%and WUE by 7–57%across North China.Our study demonstrates that there is a large potential to increase yield and WUE simultaneously by combining ridge-furrow planting with film mulching and supplemental irrigation in different potato planting regions with limited water resources.
文摘Several studies have reported a significant yearly decrease in forest cover globally, using satellite images. This is especially true in West Africa, where rapid urbanisation acerbates the problem, and both of these changes lead to alterations in rainfall regime and other changes in climatic parameters. Several studies reveal that adaptation which reduces vulnerability to adverse climatic variation effects is the key to developing resilience against climate change. In this region, over 90% of farmers are engaged in small-scale rainfed crop cultivation and rely on their own weather perception, instincts and what they observe from the surrounding biota (flora and fauna) to forecast the weather and plan their agricultural activities. The pressing nature of the problem of climate variability in Africa had provoked a lot of research into developing and testing several adaptation strategies to control the situation. Various strategies to improve and localize global, regional and national climate services (Local Forecast, Scientific Forecast and Integrated Forecast) needed by the farmers are being developed to build resilience against climate change. This review illustrates the situation in Ghana and identifies various forecast strategies developed to mitigate the adverse effects of climate variability on agricultural productivity. These mitigation methods include the development of climate services to provide users with forecast information in order to make climate-smart decisions to minimize the risk.
文摘Based on the soil moisture data from the locating experiments from 1986—1990, and using the water balance method, the water supply and demand state in the field of winter wheat, and the ways for improving water condition in dryland of dry subhumid area of the Loess Plateau were studied. The results suggested that a low precipitation satisfying ratio of 42.9%—58.8% appears in the growing period of winter wheat, and the yield, to a great extent depended on the water that was stored in deep soil layer in the previous rainy season. The filed trial results showed that tillage in the summer fallow period,straw cover, soil moisture regulation with adequate fertilization, crop rotation and proper cropping system could be the efficient ways for improving the water condition,and for the exploitation and utilization of natural water resources(both precipitation and soil water) in the winter wheat field of dryland.
基金supported by the National Natural Science Foundation of China(31572460)the Fundamental Research Funds for the Central Universities(lzujbky-2017-ot01)the National Key Research and Development Program of China(2016YFC0400302)
文摘Reduced tillage provides ecological and economic benefits to arable land on the Loess Plateau of China, where soil erosion has long been a serious problem and soil water availability is largely restricted. However, high abundances of weeds in reduced tillage systems cause significant yield losses. In this study, we explored the effects of no-tillage and stubble retention on the number and density of weeds and weed seeds in a 12-year maize-winter wheat-common vetch rotation on the Loess Plateau. Four treatments including conventional tillage, no-tillage, conventional tillage＋stubble retention and no-tillage＋stubble retention were designed and applied. We found that no-tillage increased the number of weed species and weed density in most of the crops, while stubble retention decreased weed density in maize and tended to suppress weeds in both no-tillage treatments（no-tillage and no-tillage＋stubble retention）. No-tillage led to an increase in the number of weed species in the weed seedbank and tended to increase seed density during the spring growth of winter wheat, but it decreased seed density during post-vetch fallow. Stubble retention tended to reduce seed density during the spring growth of winter wheat and post-vetch fallow. We concluded that no-tillage can promote weeds in the experimental crop rotation, while stubble retention suppresses weeds in untilled fields. The combined effects of stubble retention and no-tillage on weed suppression varied among the three crops. Based on these results, we recommend stubble retention in untilled legume-crop rotations on the Loess Plateau to improve the control of weeds.
