[Objective] The aim was to research balance between manure of breeding farm and farmland load. [Method] N balance of farmlands after manure fertilized was researched in a hoggery in Beijing （600 base sows and 647 bre...[Objective] The aim was to research balance between manure of breeding farm and farmland load. [Method] N balance of farmlands after manure fertilized was researched in a hoggery in Beijing （600 base sows and 647 breeding pigs）. [Result] The suitable N input in neighboring farmlands was 191.9 kg/（hm 2 ·y） and the farmland area satisfying balance between growing and breeding was 53.7 hm 2 in the hoggery. [Conclusion] The research provided a scientific method for balance between growing and breeding.展开更多
The importance and necessity of implementing the balance system of farmland requisition and compensation are reasoned.The changing path of the balance system of farmland requisition-compensation is overviewed.In addit...The importance and necessity of implementing the balance system of farmland requisition and compensation are reasoned.The changing path of the balance system of farmland requisition-compensation is overviewed.In addition,the problems exist in the implementation of the balance system of farmland requisition-compensation are analyzed as well,covering the increasing demands on land in the process of economic development;the serious phenomenon of wasting land in urban construction;part of farmlands should be revoked from the perspective of ecological construction and environmental protection,which lead to the shortage of reserved farmland and it is hard to implement the balance system of farmland requisition-compensation;the problems of "occupying more but compensating less,occupying good land but compensating bad land" are universal;the development and reclamation of farmlands have taken certain threats to ecological environment;the differences of various regions have not been taken into consideration in implementing the balance system of farmland requisition-compensation.Some notes on the developing trend of farmlands requisition-compensation balance system are put forward.The farmlands should be occupied after being compensated first,so as to ensure the dynamic balance of the total amount of farmlands;the government should encourage the improvement of farmland with mediocre and low output,so as to enhance its production capability;the potential of urban and rural construction land use should be fully developed and the occupation of farmland should be reduced as few as possible;various aspects should be cooperated to increase the possibility of requisition-compensation among different regions.展开更多
The article puts forward the process and means of regional water and land balance research, and then from two scenarios which are the balances under natural regulation and human intervention, calculated and analysed t...The article puts forward the process and means of regional water and land balance research, and then from two scenarios which are the balances under natural regulation and human intervention, calculated and analysed the balance between water and land on Ningxia Plain. For the balance under natural regulation named farmland water balance, using farmland water resource balance equation, the research estimated the monthly farmland water balance of 8 major crops for all of the 12 counties on Ningxia Plain in the period of 1960-2001; for the balance under human intervention, the research estimated land-use water balance equation of the counties in 2000, and calculated the balance between land use and water resources including irrigating water of all the 12 counties on Ningxia Plain. Results showed that①precipitation can not meet the water demand of the crops for growth and development on Ningxia Plain, and water shortage is the primary character of farmland water balance under natural regulation,②the diversity of water and land balance of different counties is distinctly influenced by the crop structure, water quantity for irrigation and irrigation level.③Irrigation water could meet the crop water demand on Ningxia Plain in 2000, but there was not much space to expand irrigating cultivated land.展开更多
To evaluate the nitrogen pollution load in an aquifer, a water and nitrogen balance analysis was conducted over a thirty-five year period at five yearly intervals. First, we established a two-horizon model comprising ...To evaluate the nitrogen pollution load in an aquifer, a water and nitrogen balance analysis was conducted over a thirty-five year period at five yearly intervals. First, we established a two-horizon model comprising a channel/soil horizon, and an aquifer horizon, with exchange of water between the aquifer and river. The nitrogen balance was estimated from the product of nitrogen concentration and water flow obtained from the water balance analysis. The aquifer nitrogen balance results were as follows: 1) In the aquifer horizon, the total nitrogen pollution load potential (NPLP) peaked in the period 1981-1990 at 1800 t·yr-1;following this the NPLP rapidly decreased to about 600 t·yr-1 in the period 2006-2010. The largest NPLP input component of 1000 t·yr-1 in the period 1976-1990 was from farmland. Subsequently, farmland NPLP decreased to only 400 t·yr-1 between 2006 and 2010. The second largest input component, 600 t·yr-1, was effluent from wastewater treatment works (WWTWs) in the period 1986-1990;this also decreased markedly to about 100 t·yr-1 between 2006 and 2010;2) The difference between input and output in the aquifer horizon, used as an index of groundwater pollution, peaked in the period 1986-1990 at about 1200 t·yr-1. This gradually decreased to about 200 t·yr-1 by 2006-2010. 3) The temporal change in NPLP coincided with the nitrogen concentration of the rivers in the study area. In addition, nitrogen concentrations in two test wells were 1.0 mg·l-1 at a depth of 150 m and only 0.25 mg·l-1 at 50 m, suggesting gradual percolation of the nitrogen polluted water deeper in the aquifer.展开更多
文摘[Objective] The aim was to research balance between manure of breeding farm and farmland load. [Method] N balance of farmlands after manure fertilized was researched in a hoggery in Beijing （600 base sows and 647 breeding pigs）. [Result] The suitable N input in neighboring farmlands was 191.9 kg/（hm 2 ·y） and the farmland area satisfying balance between growing and breeding was 53.7 hm 2 in the hoggery. [Conclusion] The research provided a scientific method for balance between growing and breeding.
文摘The importance and necessity of implementing the balance system of farmland requisition and compensation are reasoned.The changing path of the balance system of farmland requisition-compensation is overviewed.In addition,the problems exist in the implementation of the balance system of farmland requisition-compensation are analyzed as well,covering the increasing demands on land in the process of economic development;the serious phenomenon of wasting land in urban construction;part of farmlands should be revoked from the perspective of ecological construction and environmental protection,which lead to the shortage of reserved farmland and it is hard to implement the balance system of farmland requisition-compensation;the problems of "occupying more but compensating less,occupying good land but compensating bad land" are universal;the development and reclamation of farmlands have taken certain threats to ecological environment;the differences of various regions have not been taken into consideration in implementing the balance system of farmland requisition-compensation.Some notes on the developing trend of farmlands requisition-compensation balance system are put forward.The farmlands should be occupied after being compensated first,so as to ensure the dynamic balance of the total amount of farmlands;the government should encourage the improvement of farmland with mediocre and low output,so as to enhance its production capability;the potential of urban and rural construction land use should be fully developed and the occupation of farmland should be reduced as few as possible;various aspects should be cooperated to increase the possibility of requisition-compensation among different regions.
基金porject KZCX3-SW-333 Supponted by Chinese Academy of Saience
文摘The article puts forward the process and means of regional water and land balance research, and then from two scenarios which are the balances under natural regulation and human intervention, calculated and analysed the balance between water and land on Ningxia Plain. For the balance under natural regulation named farmland water balance, using farmland water resource balance equation, the research estimated the monthly farmland water balance of 8 major crops for all of the 12 counties on Ningxia Plain in the period of 1960-2001; for the balance under human intervention, the research estimated land-use water balance equation of the counties in 2000, and calculated the balance between land use and water resources including irrigating water of all the 12 counties on Ningxia Plain. Results showed that①precipitation can not meet the water demand of the crops for growth and development on Ningxia Plain, and water shortage is the primary character of farmland water balance under natural regulation,②the diversity of water and land balance of different counties is distinctly influenced by the crop structure, water quantity for irrigation and irrigation level.③Irrigation water could meet the crop water demand on Ningxia Plain in 2000, but there was not much space to expand irrigating cultivated land.
文摘To evaluate the nitrogen pollution load in an aquifer, a water and nitrogen balance analysis was conducted over a thirty-five year period at five yearly intervals. First, we established a two-horizon model comprising a channel/soil horizon, and an aquifer horizon, with exchange of water between the aquifer and river. The nitrogen balance was estimated from the product of nitrogen concentration and water flow obtained from the water balance analysis. The aquifer nitrogen balance results were as follows: 1) In the aquifer horizon, the total nitrogen pollution load potential (NPLP) peaked in the period 1981-1990 at 1800 t·yr-1;following this the NPLP rapidly decreased to about 600 t·yr-1 in the period 2006-2010. The largest NPLP input component of 1000 t·yr-1 in the period 1976-1990 was from farmland. Subsequently, farmland NPLP decreased to only 400 t·yr-1 between 2006 and 2010. The second largest input component, 600 t·yr-1, was effluent from wastewater treatment works (WWTWs) in the period 1986-1990;this also decreased markedly to about 100 t·yr-1 between 2006 and 2010;2) The difference between input and output in the aquifer horizon, used as an index of groundwater pollution, peaked in the period 1986-1990 at about 1200 t·yr-1. This gradually decreased to about 200 t·yr-1 by 2006-2010. 3) The temporal change in NPLP coincided with the nitrogen concentration of the rivers in the study area. In addition, nitrogen concentrations in two test wells were 1.0 mg·l-1 at a depth of 150 m and only 0.25 mg·l-1 at 50 m, suggesting gradual percolation of the nitrogen polluted water deeper in the aquifer.
