Fixed and random effect models were applied to a pseudo-panel data built of soil analysis reports from tobacco farms to analyze relationships between soil characteristics like soil organic matter (SOM) and soil nitrog...Fixed and random effect models were applied to a pseudo-panel data built of soil analysis reports from tobacco farms to analyze relationships between soil characteristics like soil organic matter (SOM) and soil nitrogen (N), phosphorous (P) and potassium (K) and to explore the potential for improving nutrients availability by increasing SOM content. These econometric models may account for unobserved specific characteristics such as location-specific characteristics, management strategies, farmers’ skills and preferences and environmental heterogeneity. Positive relationships were found between N, P and K availability and SOM. The random effect model reports a highly significant elasticity of N with respect to SOM of 0.75, meaning that an increase of 1% of SOM will increase soil N by 0.75%. Using this elasticity, the required SOM improvement of green manure was calculated at which costs of green manure would exactly equal benefits in terms of reduced N fertilizer use. Costs and benefits are equal if the SOM increases from 1.55% to 3.61%, which is barely achieved according to the literature. Hence, growing green manure crops to increase SOM and thereby N availability is not economically attractive. However, additional benefits may arise from SOM improvement and growing green manure crops.展开更多
Animal production systems convert plant protein into animal protein. Depending on animal species, ration and management, between 5% and 45 % of the nitrogen (N) in plant protein is converted to and deposited in animal...Animal production systems convert plant protein into animal protein. Depending on animal species, ration and management, between 5% and 45 % of the nitrogen (N) in plant protein is converted to and deposited in animal protein. The other 55%-95% is excreted via urine and feces, and can be used as nutrient source for plant (= often animal feed) production. The estimated global amount of N voided by animals ranges between 80 and 130 Tg N per year, and is as large as or larger than the global annual N fertilizer consumption. Cattle (60%), sheep (12%) and pigs (6%) have the largest share in animal manure N production.The conversion of plant N into animal N is on average more efficient in poultry and pork production than in dairy production, which is higher than in beef and sheep production. However, differences within a type of animal production system can be as large as differences between types of animal production systems, due to large effects of the genetic potential of animals, animal feed and management. The management of animals and animal feed, together with the genetic potential of the animals, are key factors to a high efficiency of conversion of plant protein into animal protein.The efficiency of the conversion of N from animal manure, following application to land, into plant protein ranges between 0 and 60%, while the estimated global mean is about 15%. The other 40%- 100% is lost to the wider environment via NH3 volatilization, denitrification, leaching and run-off in pastures or during storage and/or following application of the animal manure to land. On a global scale, only 40%-50% of the amount of N voided is collected in barns, stables and paddocks, and only half of this amount is recycled to crop land. The N losses from animal manure collected in barns, stables and paddocks depend on the animal manure management system. Relative large losses occur in confined animal feeding operations, as these often lack the land base to utilize the N from animal manure effectively.Losses will be relatively low when all manure are collected rapidly in water-tight and covered basins, and when they are subsequently applied to the land in proper amounts and at the proper time, and using the proper method (low-emission techniques).There is opportunity for improving the N conversion in animal production systems by improving the genetic production potential of the herd, the composition of the animal feed, and the management of the animal manure. Coupling of crop and animal production systems, at least at a regional scale, is one way to high N use efficiency in the whole system. Clustering of confined animal production systems with other intensive agricultural production systems on the basis of concepts from industrial ecology with manure processing is another possible way to improve Nuse efficiency.展开更多
Realizing sustainable development has become a global priority.This holds,in particular,for agriculture.Recently,the United Nations launched the Sustainable Development Goals(SDGs),and the Nineteenth National People’...Realizing sustainable development has become a global priority.This holds,in particular,for agriculture.Recently,the United Nations launched the Sustainable Development Goals(SDGs),and the Nineteenth National People’s Congress has delivered a national strategy for sustainable development in China—realizing green development.The overall objective of Agriculture Green Development(AGD)is to coordinate"green"with"development"to realize the transformation of current agriculture with high resource consumption and high environmental costs into a green agriculture and countryside with high productivity,high resource use efficiency and low environmental impact.This is a formidable task,requiring joint efforts of government,farmers,industry,educators and researchers.The innovative concept for AGD will focus on reconstructing the whole crop-animal production and food production-consumption system,with the emphasis on high thresholds for environmental standards and food quality as well as enhanced human well-being.This paper addresses the significance,challenges,framework,pathways and potential solutions for realizing AGD in China,and highlights the potential changes that will lead to a more sustainable agriculture in the future.Proposals include interdisciplinary innovations,whole food chain improvement and regional solutions.The implementation of AGD in China will provide important implications for the countries in developmental transition,and contribute to global sustainable development.展开更多
1 INTRODUCTION This special issue contains a collection of papers dealing with various aspects of Integrating livestock and crop production systems in different parts of the world.Drafts of some papers were presented ...1 INTRODUCTION This special issue contains a collection of papers dealing with various aspects of Integrating livestock and crop production systems in different parts of the world.Drafts of some papers were presented and discussed at a 2-day international workshop in Quzhou,Hebei,China,during October 9-12,2019.The workshop was combined with a 2-day field trip to visit dairy and poultry farms and rural villages in Hebei.展开更多
The term Agriculture Green Development(AGD)was introduced by the 19 th National Congress of China’s CPCC in2017 as a name for the national strategy of sustainable development to realize green development.This nationa...The term Agriculture Green Development(AGD)was introduced by the 19 th National Congress of China’s CPCC in2017 as a name for the national strategy of sustainable development to realize green development.This national strategy aims at fundamental solutions for the so called three rural issues:(1)agriculture.展开更多
Pollution of high-altitude lake basins by agriculture and rural activities,and the control of this pollution,have received increasing attention from academic research and government policy in China.Series of restricti...Pollution of high-altitude lake basins by agriculture and rural activities,and the control of this pollution,have received increasing attention from academic research and government policy in China.Series of restrictions and regulations have been implemented to protect the surface,water quality.These restrictions and regulations have greatly impacted and transformed the agricultural systems and rural livelihoods surrounding these lake basins.Using Erhai Lake basin in Yunnan Province as a case study,three main challenges were identified for concurrently decreasing pollution in the lake and increasing farmer income.It is contended that scientifically-sound environmental protection policies and agricultural green development practices are key to reversing the current situation.This will help to protect the lake from pollution while smallholder farmers will be able to produce healthy food in an environmentally sustainable manner,and with a fair remuneration for all the services farmers providetothe society.展开更多
Reconciling the tasks of producing adequate amounts of nutritious food for the increasing global population while preserving the environment and natural ecosystems simultaneously is an enormous challenge. The concept ...Reconciling the tasks of producing adequate amounts of nutritious food for the increasing global population while preserving the environment and natural ecosystems simultaneously is an enormous challenge. The concept of agriculture green development(AGD) and the necessary governmental policies were developed to address the aforementioned challenge in China and to help achieve the related global sustainable development goals. Agriculture green development emphasizes the synergy between green and development;current agriculture has to transform from the intensive farming with high inputs, high environmental impacts and low resource-use efficiency to a more sustainable agriculture, in order to ensure an adequate supply of nutritious food while delivering environmental integrity, improved economic profitability,and social equity. A research program on AGD was established by China Agricultural University with four research themes, namely: green crop production, green integrated crop-animal production, green food and industry,and green ecological environment and ecosystem services, to provide a scientific basis for future developments and to facilitate the implementation of AGD in practice. AGD requires a multistakeholder approach, fueled by innovative and interdisciplinary research. Joint actions have to be taken by governments, farmers, supply industries, consumers, educators, extension services and researchers to support AGD. This requires strong coordination and public awareness campaigns. This review presents the progress that has been made over the past 5 years and makes recommendations for more research and development, in order to better deliver agricultural green and sustainable development on national and international scales.展开更多
Urban population growth is driving the expansion of urban and peri-urban agriculture(UPA)in developing countries.UPA is providing nutritious food to residents but the manures produced by UPA livestock farms and other ...Urban population growth is driving the expansion of urban and peri-urban agriculture(UPA)in developing countries.UPA is providing nutritious food to residents but the manures produced by UPA livestock farms and other wastes are not properly recycled.This paper explores the effects of four scenarios:(1)a reference scenario(business as usual),(2)increased urbanization,(3)UPA intensification,and(4)improved technology,on food-protein self-sufficiency,manure nitrogen(N)recycling and balances for four different zones in a small city(Jimma)in Ethiopia during the period 2015-2050.An N mass flow model with data from farm surveys,field experiments and literature was used.A field experiment was conducted and N use efficiency and N fertilizer replacement values differed among the five types of composts derived from urban livestock manures and kitchen wastes.The N use efficiency and N fertilizer replacement values were used in the N mass flow model.Livestock manures were the main organic wastes in urban areas,although only 20 to 40%of animal-sourced food consumed was produced in UPA,and only 14 to 19%of protein intake by residents was animal-based.Scenarios indicate that manure production in UPA will increase 3 to 10 times between 2015 and 2050,depending on urbanization and UPA intensification.Only 13 to 38%of manure N will be recycled in croplands.Farm-gate N balances of UPA livestock farms will increase to>1 t·ha−1 in 2050.Doubling livestock productivity and feed protein conversion to animal-sourced food will roughly halve manure N production.Costs of waste recycling were high and indicate the need for government incentives.Results of these senarios are wake-up calls for all stakeholders and indicate alternative pathways.展开更多
Increasing amounts of nitrogen fertilizer have been used in agriculture during the last decades to boost food production for the increasing global human population.The marked increase in reactive nitrogen use has also...Increasing amounts of nitrogen fertilizer have been used in agriculture during the last decades to boost food production for the increasing global human population.The marked increase in reactive nitrogen use has also contributed to severe nitrogen pollution and multiple impacts on human and ecosystems'health.1 Nitrogen is an important precursor to air pollution(e.g.,fine particulate matter,near-surface ozone),water pollution(algal blooms,nitrate contamination),biodiversity loss(nitrogen deposition and eutrophication),soil acidification(ammonium fertilizer use),and global warming(nitrous oxide).2 Agricultural nitrogen pollution has decreased in some high-income countries,such as those in the European Union(EU),during the last decades,but the remaining nitrogen pollution still causes serious damage.The societal cost of nitrogen pollution by agriculture in the EU has been estimated to range from V35 to V230 billion per year and this cost appears to be greater than the farm profits from nitrogen fertilizer use,which range from V20 to V80 billion per year.3 Socioeconomic trade-offs between farmers and society need to be introduced to decrease nitrogen pollution.展开更多
In 2015,17 Sustainable Development Goals(SDGs)were approved,including SDG13,which addresses actions to increase carbon capture(CO_(2)-C storage)for climate change mitigation.However,no analytical procedures have been ...In 2015,17 Sustainable Development Goals(SDGs)were approved,including SDG13,which addresses actions to increase carbon capture(CO_(2)-C storage)for climate change mitigation.However,no analytical procedures have been defined for quantifying soil organic carbon(SOC)sequestration.This paper presents a rapid tool for guiding farmers and for monitoring SOC sequestration in farmer fields.The tool consists of multiconstituent soil analyses through near-infrared spectroscopy(NIRS)and an SOC mineralization model.The tool provides forecasts of SOC sequestration over time.Soil analyses by NIRS have been calibrated and validated for farmer fields in European countries,China,New Zealand,and Vietnam.Results indicate a high accuracy of determination for SOC(R^(2)≥0.93),and for inorganic C,soil texture,and soil bulk density.Permanganate oxidizable soil C is used as proxy for active SOC,to detect early management-induced changes in SOC contents,and is also quantified by NIRS(R^(2)=0.92).A pedotransfer function is used to convert the results of the soil analyses to SOC sequestration in kg·ha^(-1)C as well as CO_(2).In conclusion,the tool allows fast,quantitative,and action-driven monitoring of SOC sequestration in farmer fields,and thereby is an essential tool for monitoring progress of SDG13.展开更多
Many grassland-based dairy farms are intensifying production,i.e.,produce more milk per ha of land in response to the increasing demand for milk(by about 2%per year)in a globalized market.However,intensive dairy farmi...Many grassland-based dairy farms are intensifying production,i.e.,produce more milk per ha of land in response to the increasing demand for milk(by about 2%per year)in a globalized market.However,intensive dairy farming has been implicated for its resources use,ammonia and greenhouse gas emissions,and eutrophication impacts.This paper addresses the question of how the intensity of dairy production relates to N and P surpluses and use efficiencies on farms subjected to agri-environmental regulations.Detailed monitoring data were analyzed from 2858 grassland-based dairy farms in The Netherlands for the year 2015.The farms produced on average 925 Mg·yr^(-1)milk.Milk production per ha ranged from<10 to>30 Mg·ha^(-1)·yr^(-1).Purchased feed and manure export strongly increased with the level of intensification.Surpluses of N and P at farm level remained constant and ammonia emissions per kg milk decreased with the level of intensification.In conclusion,N and P surpluses did not differ much among dairy farms greatly differing in intensity due to legal N and P application limits and obligatory export of manure surpluses to other farms.Further,N and P use efficiencies also did not differ among dairy farms differing in intensity provided the externalization of feed production was accounted for.This paper provides lessons for proper monitoring and control of N and P cycling in dairy farming.展开更多
The idea of a carbon-neutral agriculture is appealing and overwhelming at the same time.It is appealing because agriculture may and has to contribute to decreasing the influence of humans on the climate system through...The idea of a carbon-neutral agriculture is appealing and overwhelming at the same time.It is appealing because agriculture may and has to contribute to decreasing the influence of humans on the climate system through a drastic decrease of the net emissions of carbon dioxide,methane and nitrous oxide from agriculture to the atmosphere.展开更多
文摘Fixed and random effect models were applied to a pseudo-panel data built of soil analysis reports from tobacco farms to analyze relationships between soil characteristics like soil organic matter (SOM) and soil nitrogen (N), phosphorous (P) and potassium (K) and to explore the potential for improving nutrients availability by increasing SOM content. These econometric models may account for unobserved specific characteristics such as location-specific characteristics, management strategies, farmers’ skills and preferences and environmental heterogeneity. Positive relationships were found between N, P and K availability and SOM. The random effect model reports a highly significant elasticity of N with respect to SOM of 0.75, meaning that an increase of 1% of SOM will increase soil N by 0.75%. Using this elasticity, the required SOM improvement of green manure was calculated at which costs of green manure would exactly equal benefits in terms of reduced N fertilizer use. Costs and benefits are equal if the SOM increases from 1.55% to 3.61%, which is barely achieved according to the literature. Hence, growing green manure crops to increase SOM and thereby N availability is not economically attractive. However, additional benefits may arise from SOM improvement and growing green manure crops.
文摘Animal production systems convert plant protein into animal protein. Depending on animal species, ration and management, between 5% and 45 % of the nitrogen (N) in plant protein is converted to and deposited in animal protein. The other 55%-95% is excreted via urine and feces, and can be used as nutrient source for plant (= often animal feed) production. The estimated global amount of N voided by animals ranges between 80 and 130 Tg N per year, and is as large as or larger than the global annual N fertilizer consumption. Cattle (60%), sheep (12%) and pigs (6%) have the largest share in animal manure N production.The conversion of plant N into animal N is on average more efficient in poultry and pork production than in dairy production, which is higher than in beef and sheep production. However, differences within a type of animal production system can be as large as differences between types of animal production systems, due to large effects of the genetic potential of animals, animal feed and management. The management of animals and animal feed, together with the genetic potential of the animals, are key factors to a high efficiency of conversion of plant protein into animal protein.The efficiency of the conversion of N from animal manure, following application to land, into plant protein ranges between 0 and 60%, while the estimated global mean is about 15%. The other 40%- 100% is lost to the wider environment via NH3 volatilization, denitrification, leaching and run-off in pastures or during storage and/or following application of the animal manure to land. On a global scale, only 40%-50% of the amount of N voided is collected in barns, stables and paddocks, and only half of this amount is recycled to crop land. The N losses from animal manure collected in barns, stables and paddocks depend on the animal manure management system. Relative large losses occur in confined animal feeding operations, as these often lack the land base to utilize the N from animal manure effectively.Losses will be relatively low when all manure are collected rapidly in water-tight and covered basins, and when they are subsequently applied to the land in proper amounts and at the proper time, and using the proper method (low-emission techniques).There is opportunity for improving the N conversion in animal production systems by improving the genetic production potential of the herd, the composition of the animal feed, and the management of the animal manure. Coupling of crop and animal production systems, at least at a regional scale, is one way to high N use efficiency in the whole system. Clustering of confined animal production systems with other intensive agricultural production systems on the basis of concepts from industrial ecology with manure processing is another possible way to improve Nuse efficiency.
基金supported by the Project of Beijing’s Top-Precision-Advanced Disciplinesthe CSC-AGD Ph D Program from China Scholarship Council(CSC)the Key Consulting Project of the Chinese Academy of Engineering。
文摘Realizing sustainable development has become a global priority.This holds,in particular,for agriculture.Recently,the United Nations launched the Sustainable Development Goals(SDGs),and the Nineteenth National People’s Congress has delivered a national strategy for sustainable development in China—realizing green development.The overall objective of Agriculture Green Development(AGD)is to coordinate"green"with"development"to realize the transformation of current agriculture with high resource consumption and high environmental costs into a green agriculture and countryside with high productivity,high resource use efficiency and low environmental impact.This is a formidable task,requiring joint efforts of government,farmers,industry,educators and researchers.The innovative concept for AGD will focus on reconstructing the whole crop-animal production and food production-consumption system,with the emphasis on high thresholds for environmental standards and food quality as well as enhanced human well-being.This paper addresses the significance,challenges,framework,pathways and potential solutions for realizing AGD in China,and highlights the potential changes that will lead to a more sustainable agriculture in the future.Proposals include interdisciplinary innovations,whole food chain improvement and regional solutions.The implementation of AGD in China will provide important implications for the countries in developmental transition,and contribute to global sustainable development.
文摘1 INTRODUCTION This special issue contains a collection of papers dealing with various aspects of Integrating livestock and crop production systems in different parts of the world.Drafts of some papers were presented and discussed at a 2-day international workshop in Quzhou,Hebei,China,during October 9-12,2019.The workshop was combined with a 2-day field trip to visit dairy and poultry farms and rural villages in Hebei.
文摘The term Agriculture Green Development(AGD)was introduced by the 19 th National Congress of China’s CPCC in2017 as a name for the national strategy of sustainable development to realize green development.This national strategy aims at fundamental solutions for the so called three rural issues:(1)agriculture.
基金supported by the Major Science and Technology Project of Yunnan Province (202202AE090034)the Project of Beijing’s Top-Precision-Advanced Disciplinesthe Key Consulting Project of the Chinese Academy of Engineering
文摘Pollution of high-altitude lake basins by agriculture and rural activities,and the control of this pollution,have received increasing attention from academic research and government policy in China.Series of restrictions and regulations have been implemented to protect the surface,water quality.These restrictions and regulations have greatly impacted and transformed the agricultural systems and rural livelihoods surrounding these lake basins.Using Erhai Lake basin in Yunnan Province as a case study,three main challenges were identified for concurrently decreasing pollution in the lake and increasing farmer income.It is contended that scientifically-sound environmental protection policies and agricultural green development practices are key to reversing the current situation.This will help to protect the lake from pollution while smallholder farmers will be able to produce healthy food in an environmentally sustainable manner,and with a fair remuneration for all the services farmers providetothe society.
基金financially supported by a project of Beijing’s Top-Precision-Advanced Disciplinesthe CSC-AGD PhD Program from China Scholarship Council+3 种基金the National Key Research and Development Program of China (2023YFD1901500, 2023YFD1901502)the Key Consulting Project of the Chinese Academy of EngineeringYunnan Rural Revitalization Science and Technology Project, PR China (202104BI090004)the 2115 Talent Development Program of China Agricultural University。
文摘Reconciling the tasks of producing adequate amounts of nutritious food for the increasing global population while preserving the environment and natural ecosystems simultaneously is an enormous challenge. The concept of agriculture green development(AGD) and the necessary governmental policies were developed to address the aforementioned challenge in China and to help achieve the related global sustainable development goals. Agriculture green development emphasizes the synergy between green and development;current agriculture has to transform from the intensive farming with high inputs, high environmental impacts and low resource-use efficiency to a more sustainable agriculture, in order to ensure an adequate supply of nutritious food while delivering environmental integrity, improved economic profitability,and social equity. A research program on AGD was established by China Agricultural University with four research themes, namely: green crop production, green integrated crop-animal production, green food and industry,and green ecological environment and ecosystem services, to provide a scientific basis for future developments and to facilitate the implementation of AGD in practice. AGD requires a multistakeholder approach, fueled by innovative and interdisciplinary research. Joint actions have to be taken by governments, farmers, supply industries, consumers, educators, extension services and researchers to support AGD. This requires strong coordination and public awareness campaigns. This review presents the progress that has been made over the past 5 years and makes recommendations for more research and development, in order to better deliver agricultural green and sustainable development on national and international scales.
基金part of the CASCAPE project funded by the Dutch Ministry of Foreign Affairs through the Embassy of the Kingdom of the Netherlands in Addis Ababa,Ethiopia(5120915001).
文摘Urban population growth is driving the expansion of urban and peri-urban agriculture(UPA)in developing countries.UPA is providing nutritious food to residents but the manures produced by UPA livestock farms and other wastes are not properly recycled.This paper explores the effects of four scenarios:(1)a reference scenario(business as usual),(2)increased urbanization,(3)UPA intensification,and(4)improved technology,on food-protein self-sufficiency,manure nitrogen(N)recycling and balances for four different zones in a small city(Jimma)in Ethiopia during the period 2015-2050.An N mass flow model with data from farm surveys,field experiments and literature was used.A field experiment was conducted and N use efficiency and N fertilizer replacement values differed among the five types of composts derived from urban livestock manures and kitchen wastes.The N use efficiency and N fertilizer replacement values were used in the N mass flow model.Livestock manures were the main organic wastes in urban areas,although only 20 to 40%of animal-sourced food consumed was produced in UPA,and only 14 to 19%of protein intake by residents was animal-based.Scenarios indicate that manure production in UPA will increase 3 to 10 times between 2015 and 2050,depending on urbanization and UPA intensification.Only 13 to 38%of manure N will be recycled in croplands.Farm-gate N balances of UPA livestock farms will increase to>1 t·ha−1 in 2050.Doubling livestock productivity and feed protein conversion to animal-sourced food will roughly halve manure N production.Costs of waste recycling were high and indicate the need for government incentives.Results of these senarios are wake-up calls for all stakeholders and indicate alternative pathways.
基金We thank Robert Norton for the comments and language edits.This study was supported by the National Natural Science Foundation of China(41822701 and 41773068)the National Key Research and Development Project of China(2018YFC0213300)This work contributes to the“Toward International Nitrogen Management System(INMS)”funded by the United Nations Environment Program(UNEP,GEF project ID:5400-01142).
文摘Increasing amounts of nitrogen fertilizer have been used in agriculture during the last decades to boost food production for the increasing global human population.The marked increase in reactive nitrogen use has also contributed to severe nitrogen pollution and multiple impacts on human and ecosystems'health.1 Nitrogen is an important precursor to air pollution(e.g.,fine particulate matter,near-surface ozone),water pollution(algal blooms,nitrate contamination),biodiversity loss(nitrogen deposition and eutrophication),soil acidification(ammonium fertilizer use),and global warming(nitrous oxide).2 Agricultural nitrogen pollution has decreased in some high-income countries,such as those in the European Union(EU),during the last decades,but the remaining nitrogen pollution still causes serious damage.The societal cost of nitrogen pollution by agriculture in the EU has been estimated to range from V35 to V230 billion per year and this cost appears to be greater than the farm profits from nitrogen fertilizer use,which range from V20 to V80 billion per year.3 Socioeconomic trade-offs between farmers and society need to be introduced to decrease nitrogen pollution.
文摘In 2015,17 Sustainable Development Goals(SDGs)were approved,including SDG13,which addresses actions to increase carbon capture(CO_(2)-C storage)for climate change mitigation.However,no analytical procedures have been defined for quantifying soil organic carbon(SOC)sequestration.This paper presents a rapid tool for guiding farmers and for monitoring SOC sequestration in farmer fields.The tool consists of multiconstituent soil analyses through near-infrared spectroscopy(NIRS)and an SOC mineralization model.The tool provides forecasts of SOC sequestration over time.Soil analyses by NIRS have been calibrated and validated for farmer fields in European countries,China,New Zealand,and Vietnam.Results indicate a high accuracy of determination for SOC(R^(2)≥0.93),and for inorganic C,soil texture,and soil bulk density.Permanganate oxidizable soil C is used as proxy for active SOC,to detect early management-induced changes in SOC contents,and is also quantified by NIRS(R^(2)=0.92).A pedotransfer function is used to convert the results of the soil analyses to SOC sequestration in kg·ha^(-1)C as well as CO_(2).In conclusion,the tool allows fast,quantitative,and action-driven monitoring of SOC sequestration in farmer fields,and thereby is an essential tool for monitoring progress of SDG13.
文摘Many grassland-based dairy farms are intensifying production,i.e.,produce more milk per ha of land in response to the increasing demand for milk(by about 2%per year)in a globalized market.However,intensive dairy farming has been implicated for its resources use,ammonia and greenhouse gas emissions,and eutrophication impacts.This paper addresses the question of how the intensity of dairy production relates to N and P surpluses and use efficiencies on farms subjected to agri-environmental regulations.Detailed monitoring data were analyzed from 2858 grassland-based dairy farms in The Netherlands for the year 2015.The farms produced on average 925 Mg·yr^(-1)milk.Milk production per ha ranged from<10 to>30 Mg·ha^(-1)·yr^(-1).Purchased feed and manure export strongly increased with the level of intensification.Surpluses of N and P at farm level remained constant and ammonia emissions per kg milk decreased with the level of intensification.In conclusion,N and P surpluses did not differ much among dairy farms greatly differing in intensity due to legal N and P application limits and obligatory export of manure surpluses to other farms.Further,N and P use efficiencies also did not differ among dairy farms differing in intensity provided the externalization of feed production was accounted for.This paper provides lessons for proper monitoring and control of N and P cycling in dairy farming.
文摘The idea of a carbon-neutral agriculture is appealing and overwhelming at the same time.It is appealing because agriculture may and has to contribute to decreasing the influence of humans on the climate system through a drastic decrease of the net emissions of carbon dioxide,methane and nitrous oxide from agriculture to the atmosphere.
