干旱区地膜覆盖农田下垫面反照率的观测研究  

Albedo of Cropland Covered with Plastic Film in an Arid Area in Northwest China

作　　者：陈继伟[1,2] 左洪超 

机构地区：[1]半干旱气候变化教育部重点实验室、兰州大学大气科学学院,甘肃兰州730000 [2]93811部队,甘肃兰州730020

出　　处：《干旱区研究》2014年第3期397-403,共7页Arid Zone Research

基　　金：国家重大科学研究计划“973”项目(2012CB956200);国家自然科学基金(41275019,40775017)

摘　　要：利用古浪非均匀近地层观测试验中农田站的观测资料,分析地膜覆盖农田的反照率在植物生长过程中的变化,并对其与已有反照率和土壤湿度的变化关系进行了比较。发现地膜覆盖农田的反照率在作物生长初期和茂盛期都不随土壤湿度变化;作物生长初期反照率变化表现为地膜覆盖裸土特征,平均值为0.26;作物生长茂盛期反照率变化表现为植被特征,平均值为0.19。而在作物动态生长过程中,反照率介于0.19～0.26,反照率随土壤湿度增大而增大,这与已有反照率随土壤湿度增大而减小的参数化关系存在显著性差异。Plastic film is commonly used to improve soil water use efficiency in agricultural production by sup- pressing soil evaporation in the vast arid and semiarid regions. The effect of plastic film is not only significantly dif- ferent from the physical properties of soil and vegetation, but also blocks the water cycle process in land-atmosphere interaction, and these two aspects affect surface albedo. Based on the data observed in cropland for the ＂Gulang Heterogeneous Underlying Surface Layer Experiment＂, in this paper the variation of surface albedo of cropland covered with plastic film during the vegetation growth process was researched, and the relationship between surface albedo and soil moisture content was analyzed. The results showed that the surface albedo of cropland covered with plastic film in early growth period and luxuriantly-growth period of crop did not change with the variation of soil moisture content; albedo change of cropland in early growth period of crop was similar to that of bare soil covered with plastic film, and the average value was 0.26 ; albedo change of cropland in luxuriantly-growth period of crop was similar to that of natural vegetation, and the average value was 0. 19. The albedo of cropland in dynamic growth period varied in a range of 0.19 -0.26, the albedo increased with the increase of soil moisture content, and such result was significantly different from the results in the available references.

关 键 词：地膜 地表反照率 土壤湿度 地气相互作用 陆面过程参数化 干旱区 

分 类 号：S342.1[农业科学—作物栽培与耕作技术]