内蒙古1981-2010年干湿气候类型和净第一性生产力演变

为了更好服务于内蒙古地区生态建设，提供地区大气候背景的演变过程。运用徐文铎湿润指数划分了内蒙古地区的干湿气候类型，研究结果表明:1981—2010年内蒙古半干旱区、干旱区+极干旱区面积、亚湿润区+湿润区面积分别为343 090，388 035，411 819 km²；2001—2010年半干旱区+干旱区+极干旱区面积是20世纪90年代面积的1.3倍；半湿润区+湿润区面积减少了0.5倍，地区生态环境质量进一步下降。干湿气候类型与历年降水量分布图对比显示，干旱区和极干旱区面积与200 mm降水量分布线对应；湿润区在东北地区与400 mm分布线接近；分布最广的半干旱区受温度和降水综合影响较多，与雨量带分布无明显关系。1981—2010年，温度呈显著增加趋势，降水量下降趋势属正常气候波动。地区净第一性生产力（NPP）与降水量的相关系数达到显著水平，相关系数为0.930 0，而与温度的相关系数只有-0.270 0。年代际NPP在2001—2010年下降明显，从西北到东南阶梯式降低，受影响较大的地区主要分布在呼伦贝尔市西部的典型草原和温性草甸草原，赤峰市和通辽市也下降明显；总趋势是东部区下降明显，西部区波动变化，整体下降明显。

Climate Type and Net Primary Productivity Evolution Process in Inner Mongolia During 1981-2010

In order to better serve the ecological construction in Inner Mongolia, provide the evolution process of regional climate background, we used humidity index method to analyze the types of dry and wet climate change in Inner Mongolia during 1981—2010. The results show that half arid area, arid region and subhumid area or humid area were 343 090 km², 388 035 km² and 411 819 km², respectively, in Inner Mongolia in recent 30 years. Half arid area+arid region+extremely arid areas during 2001—2010 were 1.3 times of those during 1991—2000, subhumid area+humid area decreased by 0.5 times; comparison of dry and wet climate type with historical precipitation distribution shows that arid region and below were close to the area with more than 200 mm of precipitation; humid region were close to area with more than 400 mm of precipitation in northeast of Inner Mongolia; the most widespread half arid areas were affected by the temperature and precipitation, which had nothing to do with the rainfall distribution; correlation analysis indicated that the temperature presented the significantly increasing trend, and precipitation decline resulted from the climate fluctuation in nearly 30 years; correlation coefficient of regional net primary productivity and precipitation is 0.930 0, and correlation coefficient of regional net primary productivity and temperature is only -0.270 0; the interdecadal changes indicated that NPP significantly decreased during 2001—2010, presenting the stepped down from northwest to southeast, the area greatly influenced mainly distributed in the typical steppe and meadow steppe in western of Hulunbuir City, at the same time, NPP significantly decreased in Chifeng City and Tongliao City in recent 20 years, NPP significantly decreased in eastern district area, NPP fluctuated in the western area.