LST在农业气候热量区划中的应用方法研究

根据广西的自然地理特点和现有卫星遥感资料，对国内外10多种反演LST(1and surfacete mperature，陆面温度)的分裂窗算法及其相关的参数估算方法进行了适用性分析。在此基础上找出了适用于计算广西白天LST的算法，并应用该算法计算了晴空条件下的LST，获得了逐日各个时次的LST实况分布。通过模板分析，找到了求算多年LST气候平均图的途径。针对云剔除问题，通过对公共晴空区的统计分析，建立了不同图像间的数值补偿关系，从而有效地消除了云的影响，最终处理生成了广西多年和不同季节的平均LST空间分布图像。分析结果表明：在10km以上的宏观尺度上，广西平均LST的空间分布与平均气温的空间分布规律基本一致，而在1km尺度上，LST的空间特征更为精细、客观，更有利于反映与作物生长关系更为密切的下垫面热量资源的气候分布，是农业气候区划中更为有效的热量区划因子。

Methods for Using the LST Retrieved from Satellite Remote-sensings to Investigate Agroclimatical Thermal Distribution

Based on the characters of semi-tropical climate,topography,vegetation and the NOAA/AVHRR data in Guangxi,the split-window algorithms for retrieving the LST(land surface temperature) from satellite are analyzed and compared.The results suggest that the Becker&Li algorithm is suitable to retrieve the day-time LST in Guangxi.The clear-sky day-time-averaged LST in Guangxi is imaged by using the Becker&Li algorithm.We find out the approach of calculating annual mean LST by employing appropriate templets.For the cloudy region,the pixel values are substituted by the image data of same period and close time after being calculated. The calculation is based on the correlation of clear sky image with cloudy one.At last,the clear-sky day-time-averaged LST image of Guangxi is obtained.Analysis results indicate that the LST image made by the satellite remote sensing in this research is more extensive,more particular and clearer than that from the second agroclimatic regionalization in describing the distribution of thermal resource.LST is a more effective factor of thermal regionalization.