气候变暖对黄淮海平原冬小麦生长及产量影响的数值模拟

Simulation Study on the Impact of Climate Warming on Production of Winter Wheat in Huang-Huai-Hai Plain of China

利用改进的荷兰 Wageningen农业大学的产量生态学模式 SUCROS,模拟了气候变暖引起的温度升高和降水量变化对黄淮海平原冬小麦生长发育及产量的影响。结果表明 :黄淮海平原中、北部地区 ,由于自然降水远小于小麦生育期的生理需水量 ,无灌溉条件下小麦生长相当困难 ;黄淮海平原南部地区 ,气温升高加快了冬小麦的生长发育速率 ,缩短了生育历程 ,在无土壤水分亏缺的理想状态下 ,适度升温有利于冬小麦生长及产量的提高 ;但在土壤水分亏缺时 ,温度升高 ,虽改善了冬小麦越冬条件 ,使其叶面积指数增高 ,CO2同化能力增强 ,但高温加大了土壤蒸发 ,使小麦生长中、后期水分亏缺加重 ,小麦绿叶同化能力降低 ,最终使产量下降。当气候变暖伴随降水量增大时 ,这一现象有所缓解。若气候变暖伴随降水减少 ,则产量下降加剧。模拟显示 ,流行于该区的农田林网可有效地改善农田小气候 ,提高小麦的水分利用率和干物质生长量。在气候变暖的严峻形势下 。

The modified version of the theoretical production ecological model SUCROS of Wageningen Agricultural University, the Netherlands, is used to simulate the impact of temperature increase and precipitation variation in the expectable climate warming sceneries. The results show that: in the northern part of Huang Huai Hai plain, the winter wheat can not grow normally without irrigation because the natural rainfall amount is far bellow its physiological water demands. To the southern part of the plain, temperature increase raises the development rate of wheat growth and the growing stage is shortened. If there is no soil water stress, the eco environments of wheat are more favorable under the warming scenery and the production may be higher. If the water stress is unavoidable, the warming will cause serious yield reduction. The main reason is that the water stress becomes more severe due to higher soil water evaporation when temperature is higher, though climate warming may increase the growth of green leaves and raise the CO 2 assimilation in winter. The situation can be relieved if the climate warming is accompanied with preci pitation increase. The windbreaks prevailing in this area can improve the micro metrological conditions of winter wheat. The water use efficiency and then the wheat production increase under the favorable eco environments in an agroforest ecosystem. Facing the oncoming climate warming, agroforesty should be considered as one of the most effective ways in implementing sustainable development policy in rural plain area.