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利用中国1988、1995、2000和2005年县级面板数据构建了包含气候变化因素、投入要素、自然环境条件变量的面板数据随机效应计量模型,并利用该模型研究了中国县域气候变化(主要以1988-2005年间气温、降水变动)对粮食产量的影响。研究表明,从整体上看,一定幅度内的气温上升和降水增加对我国粮食产量变动有正向作用。将气温、降水变动的影响分解到不同省份上后,可以发现气温、降水变动对中国县域粮食产量的影响存在明显的区域分异特征。气温上升和降水量的增加对中国东北、华北以及西北部省份的粮食产量提升有利,对其他省区则会产生小幅负面影响。对气温、降水变动分季进行考察的结果表明,气温、降水变动对中国县域粮食产量的影响存在季节性差异,譬如春季气温变动对中国县域粮食产量的影响并不显著,但是夏、秋、冬3季的气温对中国县域粮食产量有显著的影响,不过其影响的程度与效果各异。春、夏两季降水对中国粮食产量变化存在显著影响。
Using panel data of counties in China in 1988, 1995, 2000 and 2005, we built a panel-based random effect measurement model that includes climate change factors, input elements and natural environmental conditions variables. The model was used to study climate change in China’s counties (mainly 1988 - 2005 temperature, precipitation changes) on the impact of food production. The research shows that on the whole, the increase of temperature and precipitation within a certain range have a positive effect on the change of grain output in our country. After decomposing the effects of temperature and precipitation on different provinces, we can find that there are obvious regional differences in the effects of temperature and precipitation on the grain yield in China’s counties. Rising temperatures and increasing precipitation are good for increasing grain output in northeastern China, northern China and the northwestern provinces, with a slight negative impact on other provinces. The results of season and seasonal variations in temperature and precipitation show that there are seasonal differences in the effects of temperature and precipitation on grain yield in China. For example, the effect of spring temperature on grain yield in China is not significant, but summer, autumn and winter The temperature in 3 seasons had a significant impact on the grain yield in China’s counties, but its degree of impact and effect varied. Precipitation in spring and summer have a significant impact on the change of grain output in China.