广西冬种马铃薯种植布局对气候变暖的响应

Distribution Response of Winter Potato Planting to Climate Warming in Guangxi

研究近50年来广西气候变暖对冬种马铃薯种植布局的影响,为进一步优化广西冬种马铃薯种植布局与更好适应气候变化,保障广西粮食安全提供决策建议。利用广西90个地面气象观测站1961-2010年11月至次年3月的逐日气象资料,在用线性倾向率对广西冬种马铃薯气候区划指标的变化趋势进行分析基础上,利用GIS平台完成广西1997年气候变暖突变前、后各气候区划指标空间分布图及冬种马铃薯种植气候区划图。结果表明:近50年来广西绝大部分地区11月至次年3月≥10℃积温呈现增多趋势,气候突变后比突变前的积温平均增多了198.5℃;各地极端最低气温均呈明显升高趋势,气候突变后比突变前的平均年极端最低气温升高了1.9℃;大部分地区霜冻日数呈减少趋势,气候突变后比突变前的平均霜冻日数减少了2.6 d。受广西近50年气候变暖的影响,广西冬种马铃薯种植气候最适宜区、适宜区往北扩张,次适宜区、不适宜区往北缩小。广西气候突变前后用极端最低气温、霜冻日数表征的适宜区面积均比≥10℃积温表征的面积要小,说明极端最低气温、霜冻日数一直是制约广西冬种马铃薯扩大种植的主要气象因素。

Aiming at probing the impacts of climate change to the planting distribution of potato and further optimizing the planting distribution for adapting to climate change,this study sketched the climatological divisions,during periods anterior and posterior to the abrupt warming in 1997,of potato planting in Guangxi. The sketched divisions were based on the GIS mapping the distribution of division indicators of potatoplanting. The indicators of division were calculated by analyzing the linear tendency of thermal variables（ including accumulated temperature,extreme minimum temperature,frozen day etc.） from 91 observatories in Guangxi. Results showed significant increase of mean accumulated temperature（ ≥10 ℃） in ploughing season of winter during the recent 50 years. Relative to the anterior period of abrupt warming,the posterior accumulated temperature has increased 198. 5 ℃. The extreme minimum temperature also showed significant tendency of increase,as the annual mean extreme minimum temperature has increased 1. 9 ℃ after the abrupt warming. The tendencies of decrease in frozen day occurred in the major area and the mean frozen days have decreased 2. 6 d. These are indicating a general northward shift of optimal area and convenient area of potato planting,and the contraction of sub-convenient area and inconvenient area in the northern area.