中国灌溉水粮食生产率及其时空变异

为了评价农业引水总量的生产效益,从全国459个主要灌区的实际灌溉水和粮食生产数据入手,计算、比较了1998,2005和2010年31个省区的灌溉水粮食生产率,利用空间自相关分析方法对1998—2010年中国灌溉水粮食生产率的时空变异规律进行探究.结果显示：各省区灌溉水粮食生产率呈增大趋势,代表年的中国均值为1.03 kg/m3,最大、最小值分别为河南的2.15kg/m3和海南的0.25 kg/m3,区域间差异较大;灌溉水粮食生产率在空间上存在显著的聚集现象,聚集程度随时间变化不明显,高值省区以黄淮海平原为核心集中分布,长江以南则密集了低值省区;江西、安徽及重庆灌溉水粮食生产率的变化幅度与其相邻省区不同步,造成了局部分异特征的变化.分析了中国灌溉水粮食生产率格局的形成及其随时间变化的原因.

Spatial and temporal variation of crop water productivity in China

In order to evaluate the water use efficiency in agriculture in China, the data relevant to the water used for crop production of 459 large irrigation districts in 31 provinces in the years of 1998, 2005 and 2010 were collected; then the values of Grain Irrigation Water Productivity （G） was calculated. The spatial autoeorrelation analysis was carried out to study the spatial and temporal variation of G during 1998--2010. The results revealed that G is increased with year in every large irrigation dis- trict in all the provinces ; meanwhile, the G for a representative year is 1.03 kg/m3 , the maximum one is 2.15 kg/m3 in Henan and the minimum is 0.25 kg/m3 in Hainan. There is a clear spatial clustering phenomenon, i.e. a higher G is in Huang-Huai-Hai region whilst a lower one is found in the south of China. The amplitudes of change in G in Jiangxi, Anhui and Chongqing are different from their neighbors, a localized effect is presented. The reasons for such spatial and temporal variation of G were elaborated.