检索规则说明:AND代表“并且”;OR代表“或者”;NOT代表“不包含”;(注意必须大写,运算符两边需空一格)
检 索 范 例 :范例一: (K=图书馆学 OR K=情报学) AND A=范并思 范例二:J=计算机应用与软件 AND (U=C++ OR U=Basic) NOT M=Visual
作 者:江爱良[1]
机构地区:[1]中国科学院国家计委自然资源综合考察委员会,北京100101
出 处:《生态农业研究》1993年第4期6-14,共9页Chinese Journal of Eco-agriculture
摘 要:1950—1984年全世界粮食生产以较大的幅度增长,其间的平均增长率为每年2.9%;但1984—1992年粮食增长的幅度明显下降,平均为每年0.7%。以人均粮食来统计,1950—1980年期间,人均粮食每10年增长速率超过30%,至80年代中期人均报食开始减少。前期粮食增长较大的主要原因为科学技术的进步;而后期粮食增长减缓或衰退的主要原因被认为是全球(农业)生态环境的劣变和人口的不断增多。本文试图探讨防止人均粮食下降的主要途径。The world grain production was increasing rapidly during 1950 to 1984,and the average increasing rate was 2. 9 percent per annum during this period; but the increasing rate, however, was remarkably reduced to 0. 7 percent per annum during 1984 to 1992. The author holds that the rapid increasing rate for the former period is caused by the progress and application of science and technology to agriculture. According to the statistics it is found that the increasing rate of grain production per capita was more than 30 percent per decade during 1950 to 1980,but the rate tended downwards to negative value after middle 80's. The author considers the main causes for slowing or drop- . ping of world grain production are the globle deterioration of agro-eco-environment and the rapid increasing of world population. Then the author discussed the possible ways for preventing the dropping of world grain production.
分 类 号:S181[农业科学—农业基础科学]
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在链接到云南高校图书馆文献保障联盟下载...
云南高校图书馆联盟文献共享服务平台 版权所有©
您的IP:216.73.216.117