China's crop structure has undergone significant changes in the last two decades since 2000,with an increase in the share of cereals,vegetables,and fruit,squeezing out other crops.As a result,land productivity,nut...China's crop structure has undergone significant changes in the last two decades since 2000,with an increase in the share of cereals,vegetables,and fruit,squeezing out other crops.As a result,land productivity,nutrient supply,and carbon emissions have changed.How to reallocate limited farmland among crops to achieve the multiple goals of agrifood systems becomes an important issue.This study explores the sources of land productivity and nutrition supply growth and carbon emissions reduction,and identifies the multiple roles of crop structural change from 2003 to 2020 based on a decomposition analysis.The results reveal that the growth within crops is still the primary driver in land productivity and nutrition supply and the reduction in carbon emissions.However,structural change also plays various roles at different periods.From 2003 to 2010,crop structural change increased the total calorie supply but lowered land productivity and contributed at least 70%of the total growth of carbon emissions.The crop structure was relatively stable,and their effects were modest from 2010 to 2015.From 2015 to 2020,the crop structural change began to play a greater role and generate synergistic effects in improving land productivity,micronutrient supply,and reducing carbon emissions,contributing to approximately a quarter of the growth of land productivity and 30%of total carbon emissions reduction.These results suggest that strategies for crop structural change should comprehensively consider its multiple impacts,aiming to achieve co-benefits while minimizing trade-offs.展开更多
Environmental degradation resulting from current climate changes, including prolonged drought, land degradation, desertification, and loss of biodiversity, is presenting enormous challenges to achieve food security an...Environmental degradation resulting from current climate changes, including prolonged drought, land degradation, desertification, and loss of biodiversity, is presenting enormous challenges to achieve food security and eradication of poverty in the marginal regions （about 90% of the total area） of Egypt. In addition to the natural constraints of high temperature, wind erosion, sand dune movement, and recurrent drought, such regions are subjected to improper land and water management. Moreover, there is a lack of knowledge, technologies, and experiences to match with the current severe climatic changes. There is a great need for establishing sustainable integrated ecosystem rehabilitation and management programs to overcome such problems in the marginal areas, particularly in the Sinai Peninsula due to its strategic and social importance. A series of research and development programs have been conducted in 2006 to im- prove the livelihoods of smallholders through enhancing the efficient management and utilization of local resources that can cope with the drastic changes of climate in the Sinai Peninsula. An integrated livestock/salt-tolerant fodder crop system was introduced, in 2010 by the project teamwork of Desert Research center, Egypt, to many smallholders in the South Sinai region, where studies were conducted at both the general research and individual farmer levels. The most important results were： （1） adoption of the most salt-tolerant genotypes of three forage crops： pearl millet （Pennisetum glaucum L.）, sorghum （Sorghum bicolor）, and Sudan grass （Sorghum sudanense （Piper） Stapf.）; two cereal crops （triticale and barley）; and two oil crops： safflower （Carthamus tinctorius） and Brassica （Mustard）. Alfalfa （Medicago sativa L. and Medicago arborium）, cowpeas （Vigna sinensis L.）, fodder beets （Beta vulgaris L.）, clumping desert bunchgrass （Panicum turgedum）, ryegrass （Lolium perenne） Ray grass, forage shrubs （Kochia indica, Atriplex num- mularia, Sesbania sesban L.）, and Acacia cyanophila, Leucaena leucocephala, Porsopis cheilanses, and Prosopis jioflora were also evaluated; （2） active participation of farmers in development of management strategies to improve ir- rigation water use efficiency, forage production, and livestock production; and （3） economic evaluation at the farmer level, which showed that feeding livestock salt-tolerant fodders produced an increase of about 60% in milk production and 80% in meat production, and reduced feed costs by about 40%. Accordingly, a 70% increase of family income was achieved. It is concluded that better utilization of fragile ecosystem resources and growing salt-tolerant fodder crops may contribute to the development of marginal areas and enhance the living standards of local people through providing high-quality livestock feed materials and producing economical animal products.展开更多
An analysis of the impact of simulation modelling in three diverse crop-livestock improvement projects in Agricultural Research for Development（AR4D） reveals benefits across a range of aspects including identificati...An analysis of the impact of simulation modelling in three diverse crop-livestock improvement projects in Agricultural Research for Development（AR4D） reveals benefits across a range of aspects including identification of objectives, design and implementation of experimental programs, effectiveness of participatory research with smallholder farmers, implementation of system change and scaling-out of results.In planning change, farmers must consider complex interactions within both biophysical and socioeconomic aspects of their crop and animal production activities.For this, whole-farm models that include household models of food, workload and financial requirements have the most utility and impact.The analysis also proposes improvements in design and implementation of AR4 D projects to improve the utility of simulation modelling for securing positive agronomic and livestock outcomes and lasting legacies.展开更多
The use of nitrification inhibitors has been suggested as a strategy to decrease cadmium(Cd)accumulation in crops.However,the most efficient nitrification inhibitor for mitigating crop Cd accumulation remains to be el...The use of nitrification inhibitors has been suggested as a strategy to decrease cadmium(Cd)accumulation in crops.However,the most efficient nitrification inhibitor for mitigating crop Cd accumulation remains to be elucidated,and whether and how changes in soil microbial structure are involved in this process also remains unclear.To address these questions,this study applied three commercial nitrification inhibitors,namely,dicyandiamide(DCD),3,4-dimethylpyrazole phosphate(DMPP),and nitrapyrin(NP),to pakchoi.The results showed that both DCD and DMPP(but not NP)could efficiently decrease Cd concentrations in pakchoi in urea-and ammonium-fertilized soils.In addition,among the three tested nitrification inhibitors,DMPP was the most efficient in decreasing the Cd concentration in pakchoi.The nitrification inhibitors decreased pakchoi Cd concentrations by suppressing acidification-induced Cd availability and reshaping the soil microbial structure;the most effective nitrification inhibitor was DMPP.Ammonia oxidation generates the most protons during nitrification and is inhibited by nitrification inhibitors.Changes in environmental factors and predatory bacterial abundance caused by the nitrification inhibitors changed the soil microbial structure and increased the potential participants in plant Cd accumulation.In summary,our study identified DMPP as the most efficient nitrification inhibitor for mitigating crop Cd contamination and observed that the soil microbial structural changes caused by the nitrification inhibitors contributed to decreasing Cd concentration in pakchoi.展开更多
基金This work was supported by the National Natural Science Foundation of China(72061147002 and 72373143)the National Social Science Fund of China(22&ZD085).
文摘China's crop structure has undergone significant changes in the last two decades since 2000,with an increase in the share of cereals,vegetables,and fruit,squeezing out other crops.As a result,land productivity,nutrient supply,and carbon emissions have changed.How to reallocate limited farmland among crops to achieve the multiple goals of agrifood systems becomes an important issue.This study explores the sources of land productivity and nutrition supply growth and carbon emissions reduction,and identifies the multiple roles of crop structural change from 2003 to 2020 based on a decomposition analysis.The results reveal that the growth within crops is still the primary driver in land productivity and nutrition supply and the reduction in carbon emissions.However,structural change also plays various roles at different periods.From 2003 to 2010,crop structural change increased the total calorie supply but lowered land productivity and contributed at least 70%of the total growth of carbon emissions.The crop structure was relatively stable,and their effects were modest from 2010 to 2015.From 2015 to 2020,the crop structural change began to play a greater role and generate synergistic effects in improving land productivity,micronutrient supply,and reducing carbon emissions,contributing to approximately a quarter of the growth of land productivity and 30%of total carbon emissions reduction.These results suggest that strategies for crop structural change should comprehensively consider its multiple impacts,aiming to achieve co-benefits while minimizing trade-offs.
基金the International Centre for Biosaline Agriculture (ICBA)the Islamic Development Bank (IDB)+1 种基金the OPEC Fund for International Development (OFID)the International Fund for Agricultural Development (IFAD) for their financial support to enable the project team work of the Desert Research Center (DRC) to conduct this project
文摘Environmental degradation resulting from current climate changes, including prolonged drought, land degradation, desertification, and loss of biodiversity, is presenting enormous challenges to achieve food security and eradication of poverty in the marginal regions （about 90% of the total area） of Egypt. In addition to the natural constraints of high temperature, wind erosion, sand dune movement, and recurrent drought, such regions are subjected to improper land and water management. Moreover, there is a lack of knowledge, technologies, and experiences to match with the current severe climatic changes. There is a great need for establishing sustainable integrated ecosystem rehabilitation and management programs to overcome such problems in the marginal areas, particularly in the Sinai Peninsula due to its strategic and social importance. A series of research and development programs have been conducted in 2006 to im- prove the livelihoods of smallholders through enhancing the efficient management and utilization of local resources that can cope with the drastic changes of climate in the Sinai Peninsula. An integrated livestock/salt-tolerant fodder crop system was introduced, in 2010 by the project teamwork of Desert Research center, Egypt, to many smallholders in the South Sinai region, where studies were conducted at both the general research and individual farmer levels. The most important results were： （1） adoption of the most salt-tolerant genotypes of three forage crops： pearl millet （Pennisetum glaucum L.）, sorghum （Sorghum bicolor）, and Sudan grass （Sorghum sudanense （Piper） Stapf.）; two cereal crops （triticale and barley）; and two oil crops： safflower （Carthamus tinctorius） and Brassica （Mustard）. Alfalfa （Medicago sativa L. and Medicago arborium）, cowpeas （Vigna sinensis L.）, fodder beets （Beta vulgaris L.）, clumping desert bunchgrass （Panicum turgedum）, ryegrass （Lolium perenne） Ray grass, forage shrubs （Kochia indica, Atriplex num- mularia, Sesbania sesban L.）, and Acacia cyanophila, Leucaena leucocephala, Porsopis cheilanses, and Prosopis jioflora were also evaluated; （2） active participation of farmers in development of management strategies to improve ir- rigation water use efficiency, forage production, and livestock production; and （3） economic evaluation at the farmer level, which showed that feeding livestock salt-tolerant fodders produced an increase of about 60% in milk production and 80% in meat production, and reduced feed costs by about 40%. Accordingly, a 70% increase of family income was achieved. It is concluded that better utilization of fragile ecosystem resources and growing salt-tolerant fodder crops may contribute to the development of marginal areas and enhance the living standards of local people through providing high-quality livestock feed materials and producing economical animal products.
基金the various projects and others who participated in the review and to ACIAR and CSIRO for logistical and financial supportPC was a research manager for these projects in CSIRO
文摘An analysis of the impact of simulation modelling in three diverse crop-livestock improvement projects in Agricultural Research for Development（AR4D） reveals benefits across a range of aspects including identification of objectives, design and implementation of experimental programs, effectiveness of participatory research with smallholder farmers, implementation of system change and scaling-out of results.In planning change, farmers must consider complex interactions within both biophysical and socioeconomic aspects of their crop and animal production activities.For this, whole-farm models that include household models of food, workload and financial requirements have the most utility and impact.The analysis also proposes improvements in design and implementation of AR4 D projects to improve the utility of simulation modelling for securing positive agronomic and livestock outcomes and lasting legacies.
基金Zhejiang Provincial Natural Science Foundation of China(No.LZ21D010010).
文摘The use of nitrification inhibitors has been suggested as a strategy to decrease cadmium(Cd)accumulation in crops.However,the most efficient nitrification inhibitor for mitigating crop Cd accumulation remains to be elucidated,and whether and how changes in soil microbial structure are involved in this process also remains unclear.To address these questions,this study applied three commercial nitrification inhibitors,namely,dicyandiamide(DCD),3,4-dimethylpyrazole phosphate(DMPP),and nitrapyrin(NP),to pakchoi.The results showed that both DCD and DMPP(but not NP)could efficiently decrease Cd concentrations in pakchoi in urea-and ammonium-fertilized soils.In addition,among the three tested nitrification inhibitors,DMPP was the most efficient in decreasing the Cd concentration in pakchoi.The nitrification inhibitors decreased pakchoi Cd concentrations by suppressing acidification-induced Cd availability and reshaping the soil microbial structure;the most effective nitrification inhibitor was DMPP.Ammonia oxidation generates the most protons during nitrification and is inhibited by nitrification inhibitors.Changes in environmental factors and predatory bacterial abundance caused by the nitrification inhibitors changed the soil microbial structure and increased the potential participants in plant Cd accumulation.In summary,our study identified DMPP as the most efficient nitrification inhibitor for mitigating crop Cd contamination and observed that the soil microbial structural changes caused by the nitrification inhibitors contributed to decreasing Cd concentration in pakchoi.
