退耕还林草背景下宁夏气候生产潜力变化研究

Study on the Variation of Ningxia Climate Production Potential under the Returning Farmland to Forestland and Grassland Background

对宁夏退耕还林、还草重点区域进行研究,采用"逐步订正法"计算该地区近50年的气候生产潜力和光温生产潜力。结果表明:宁夏灌区、中部干旱带、南部山区玉米的光温生产潜力呈线性增加趋势,但考虑光、温、水3因素的气候生产潜力,因降水稀少而数值很低,无灌溉便无农业;中部干旱带冬小麦的光温生产潜力、气候生产潜力无明显趋势,但气候生产潜力变幅很大,南部山区冬小麦光温生产潜力无明显变化趋势,气候生产潜力呈弱的下降趋势,说明冬小麦生产受到水分的极大制约。利用RegCM3-WOFOST/LINGRA耦合模式模拟的气象要素数据计算了未来宁夏中、南部冬小麦气候生产潜力,均呈弱的增长趋势,说明退耕还林后宁夏气候有利于冬小麦产量的提高。

The key zones of returning farmland to forestland and grassland in Ningxia were studied.By using the ＂step by step revisal method＂,the climate production potential,light and temperature production potential in the zone in recent 50 years were counted.The light and temperature production potential of corn in Ningxia irrigated area,the central arid zone and the southern mountain area presented the linear increase trend.But when considered the climate production potential of light,temperature and water,the numerical value was very low because of the scarce rainfall,and no agriculture without the irrigation.The light and temperature production potential,climate production potential of winter wheat in the central arid zone had no significant trend,but the variation range of climate production potential was very big.The light and temperature production potential of winter wheat in the southern mountain area had no significant variation trend,and the climate production potential presented the weak decline trend.It illustrated that the production of winter wheat was greatly restricted by the water content.By using the meteorological factor data which were simulated by RegCM3-WOFOST/LINGRA coupled model,the future climate production potential of winter wheat in the central and south of Ningxia was counted.They both presented the weak increase trends.It illustrated that the climate in Ningxia was favorable to improve the yield of winter wheat after returning farmland to forestland.