全球气候变化问题虽然还存在某些不确定性，但已得到广泛认同。对气候条件颇为敏感的农业将受影响，主要效应可概括为：①农业地理限制的变动；②作物产量的变化；③对农业系统的冲击。中国农业对气候变化与波动尤其敏感，加之人口压力进一步加大和农业资源已很紧缺，粮食自给的能力将受到严重威胁，必须充分重视适应和调整对策的研究。变动性与不确定性是气候的固有特征，在评价全球气候变化对农业的影响时应该认识到这点。本文还提出了减少农业对气候变化脆弱性的建议。

Historically,China has experienced numerous climatic changes or variations.In the last hundred years,it seems that China’s climate has become generally warmer and drier.Temperature increases have been Particularly notable in the north,with less evidence of changes in South China.Records show an obvious drying trend in eastern and northwestern China since 1910.Estimations for the future climatic change include:(1) Most Parts of China l be warmer in 1990s, cooler during 2010 2030,and warmer again after 2040.(2)The greenhouse warming would strengthen the warmer period,hence the average temperature will ne in the next century,about 2℃ higher during the warmest period than that at present.In the warming process,however,there would be fluctuations in a temporal scale of 20 30years and with a extent of 0.5 1.0℃.(3)The precipitation will decrease in the east and increase in the west.China’s agricultural vulnerability to climatic change is amplified by the high degree of dependeuce on a diminishing agricultural resources base.DEspite its vast size.China is poor in agricultural resources per capita,especially cropland and water resources.On the other hand,the population will increase.So the cropland per capita will be even less.Furthermore,the productivity of cropland is hindered by water shortages.This moisture constraint on food prduction is likely to be aggravated by climate change.Investment and technology are important in adapting to climatic change.However,China’s prospects for investment and technological development in agriculture are relatively modest.There fore,the Capital put into agriculture is limited.With huge rural populations but relatively scarce scientists and technicians and with inadequate equipment in agriculture, China has very limited prospects for technological adaptation to climatic change.Most researchers agree that global climate change would impact greatly on Chinese agriculture,whatever the regional climate change may be,because Chinese agriculture is already sensitive to climate-related conditions.At least,the followings will occur:(1) A loss at least 5% of overall agricultural production as aresult of warming,because of increased evaporation.wind erosion of soil,drought,and increased frequency of typhoons.(2) Several forest species face serious losses and some forest areas will be converted to steppe,covered by non-productive hot or warm-natured shrubs and grasses.(3) Significant damage to coastal areas from even a moderate sea level rise would occur,with extensive flooding and destruction of existing salterns farm-land and fishery farms,that large food sources for coastal China.In regard to deltas,where the most productive land is found and the densest population and the richest infrastructure and settlement in China are located,half of the Zhujiang River-Delta,abut 3500 square kilometers,might be inundated,and wide scale flooding is projected for more developed areas of the Changjiang River and Huanghe River deltas.Thus the food production in China will be challenged greatly and this will happen at a time when Chinese population and living standards are increasing greatly.The future national security of food sufficiency would be in more uncertainty.The feasibility of production may shrink,the flexibility of resource-use would be less,and the vulnerability would be increased.Concerns over potential agricultural impacts of clmatic change have promoted consideration of adsptations.The question of adaptation has been approached in two ways. First,It is likely that farmers and rural communities,when faced with changed climatic conditions,will adjust their practices.Thus,any estimate of agricultural implications of changes in climate needs to consider possible "spontaneous" adaptive strategies,and the prospects for their adoption.Second.in the face of crop losses or new production opportunities associated with climatic change,public authorities may promote adjustments in the nature and organization of agricultural production,in order to minimize climate-related losses and to realize potential be