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作 者:宋佃星[1]
机构地区:[1]宝鸡文理学院陕西省灾害监测与机理模拟重点实验室,陕西宝鸡721013
出 处:《江西农业学报》2013年第2期135-139,共5页Acta Agriculturae Jiangxi
基 金:国家自然科学基金项目"秦岭南北全球变化适应度评价及可持续发展模式选择"(40871052)
摘 要:以陕西省的年鉴统计资料为依据,对其粮食生产总量、耕地面积、单产进行了分析。结果表明:粮食生产总量和单产的变化规律基本趋于一致,都呈波动增长趋势;耕地面积总体呈下降趋势,但下降趋势有所减缓。粮食生产总量由耕地面积和单产决定。制约粮食单产的主要因素有:自然灾害、农业基础设施建设与农业投入、农业生态环境、土地政策、耕地质量、农业科技水平和劳动力文化水平等。According to the statistical data of Shaanxi province in the recent years, the grain total output, cultivated land area, yield per unit area were analyzed. The results indicated that: the grain total output and yield per unit area had similar changing rule, and they all showed a rising trend; the cultivated land area was declining, but the process was slow. The grain total output was controlled by cultivated land area and yield per unit area. When the cultivated land area declined gradually, the increase of grain to- tal output must depend on the great increase of the yield per unit area. The main restrictive factors of yield per unit area included natural disaster, agricultural infrastructure and agricultural input, ecological environment, land policy, quality of cultivated land, the level of agricultural science and technology, culture competence of labor force and so on.
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