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作 者:胡瑞法 黄季焜 HU Rui-fa;HUANG Ji-kun(Institute of Advanced Agricultural Sciences,Peking University,Weifang 261200,China;School of Advanced Agricultural Sciences,Peking University,Beijing 100091,China)
机构地区:[1]北京大学现代农业研究院,山东潍坊261200 [2]北京大学现代农学院,北京100091
出 处:《华南农业大学学报(社会科学版)》2024年第5期75-83,共9页Journal of South China Agricultural University(Social Science Edition)
基 金:国家自然科学基金项目(71661147002)。
摘 要:粮食单产不仅是粮食安全的重要指标,同时也是科技进步的重要体现。在比较过去60年中国与三大粮食主要生产国的单产水平变动趋势和差异,并采用Tornqvist指数法分别测算1980—2020年中国三大粮食单产的投入产出和全要素生产率指数的基础上分析粮食单产变化的原因。研究发现:改革开放以来,中国三大粮食的单产增长与发达国家相比呈现不同的趋势,这一差异与政府研发体制和新技术采用的差异有关。中国未及时采用转基因玉米技术进一步扩大与美国的玉米单产差异。相对于知识产权容易保护的杂交玉米等作物,以跨国公司为主的种子公司对知识产权难以保护的小麦品种研发投入相对较少,使美国等国家的小麦单产水平增长慢于中国;转基因玉米的商业化种植扩大了美国、巴西等国家玉米单产与未批准该技术商业化种植国家玉米单产的差距。中国三大粮食单产的全要素生产率增速小麦>水稻>玉米,粮食单产增长主要以劳动节约和资金替代劳动的技术为特征。The yield of major grain crops per unit is not only an important indicator of food security,but also an important embodiment of scientific and technological progress.This study compares the changing trends of yield on rice,wheat and maize between China and the major crop producing countries during the past 60 years.The Tornqvist index method was used to measure the changes in total factor productivity and input-output index was used to analyze the reasons of the changes in yield of rice,wheat and maize yields in China.The results show that since the reform and opening up,China s yields of major grains have shown different trends in growth compared with those of developed countries,and that this difference is related to differences in the government s R&D system and the adoption of new technologies.China has not adopted genetically modified(GM)maize technology in time further widened the maize yield difference with the United States.Compared with hybird wheat varieties——the intellectual property rights of which are hard to protect,the seed companies,dominated by multinational corporations(MNC),invested more on the development of hybird maize varieties(intellectual property rights are easier to protect).As a result,the wheat yield per unit area in the United States increases more slowly than that of China.The commercial production of GM maize in the United States and Brazil has widened the yield gap between the countries that have not approved GM technology.The total factor productivity per unit of the three crops increased the fastest in wheat and the slowest in maize.The increase of the three crops yield is characterized by labor saving and capital substitution of labor.
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