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一、中国的农业环境问题1.气候变化近年来,CO_2温室效应对全球的影响及其可能带来的环境问题,已成为许多国家政府普遍关注的一个重大问题。研究表明,近百年来大气中的CO_2浓度迅速增加,预计到2030年～2050年将比现在增加一倍,近百年来全球气候变化的总趋势是增暖。随着气温的升高,我国的种植熟制界限可能北移,一熟制减少,二熟、三熟制增加。加上大气CO_2浓度的增高,作物光合作用能力增强,这对我国的粮食生产极为有利。2.资源问题农业资源包括气候资源、植物种质资源、土地资源、水资源、劳动力资源等。从目前情况看,限制我国农业发展的资源主要是土地资源,冰资源及劳动力资源。土地资源问题:我国国土面积辽阔,但人均耕地仅占世界人均水平的1/3。我国耕地的质量一般较差,60%的耕地分布于山地、丘陵和高原地区,而且62%的耕地分布于淮河以北的干早、半干早地区,全国仅有39%的耕地有水源保证和灌溉设施。同时,由于我国近年来工业化的发展,城镇建设、基础设施建设等,挤占了大量耕地。据国家土地管理部门的资料,1986年～1995年我国耕地减少550万公顷。因
I. China’s Agricultural Environment 1. Climate Change In recent years, the global impact of CO 2 greenhouse effect and its possible environmental problems have become a major issue that has been generally concerned by many governments. The research shows that the concentration of CO 2 in the atmosphere has rapidly increased in the past 100 years and is expected to double from 2030 to 2050. The general trend of global climate change in recent 100 years is warming. With the temperature rising, the boundary of cultivation of our country may move northward, the decrease of one-cropping system, the increase of second-cropping and three-cropping system. Coupled with the increase of atmospheric CO 2 concentration, photosynthetic capacity of crops is enhanced, which is extremely beneficial to China’s grain production. 2. Resource issues Agricultural resources include climate resources, plant germplasm resources, land resources, water resources, labor resources and so on. Judging from the current situation, the resources that limit China’s agricultural development are mainly land resources, ice resources and labor resources. Land Resource Issues: Our country has a vast land area, but only a third of the world’s per capita arable land. The quality of arable land in our country is generally poor. 60% of the arable land is distributed in the mountainous, hilly and plateau areas, and 62% of the arable land is distributed in dry and semi-dry areas north of the Huaihe River. Only 39% And irrigation facilities. In the meantime, due to the industrialization in our country in recent years, urban construction and infrastructure construction have taken up a large amount of cultivated land. According to the information of the State Land Management Department, from 1986 to 1995, China reduced its cultivated land by 5.5 million hectares. because