草业学报2012，Vol.21Issue(1)：239-247,9.
基于MODIS算法的藏北高寒草甸的光能利用效率模拟
Modelling light use efficiency of alpine meadows on the Northern Tibetan Plateau based on the MODIS algorithm
摘要
Abstract
Light use efficiency (LUE) is defined as the ratio of primary production to absorbed photosynthetical-ly active radiation (APAR) by a vegetation canopy and it reflects the capability of using luminous energy. Quantitative analysis of the temporal and spatial variations of primary production is based on the quantitative a-nalysis LUE and is an important component of quantitative analysis of the global carbon cycle. Therefore, quantitative analysis of the global vegetation LUE is an important component of quantitative analysis of the global carbon cycle. The LUE of alpine meadows on the Northern Tibetan Plateau were modeled based on the MODIS LUE algorithm in 2004 - 2005. Daily minimum air temperature ( Tamin) and vapor pressure deficit (VPD) were used to calculate the temperature attenuation scalar (Tscalar) and water attenuation scalar (Wscalar), respectively. Based on correlation analysis and multiple stepwise linear regression analysis, the Tscalar might explain more seasonal variations of LUE than the Wscalar. Modeled LUE values were about 14. 97% and 16. 57% larger than observed LUE values in 2004 and 2005, respectively. However, there was no significant difference between modeled LUE and observed LUE. This means that the LUE model based on the MODIS algorithm had high accuracy to model LUE of alpine meadows on the Northern Tibetan Plateau. Correlation analysis showed that the correlation coefficient between observed LUE and Tamin was larger than that between observed LUE and mean air temperature. This indicated that Tamin was better than mean air temperature in quantitative analysis of the LUE seasonal change. The LUE model based on the MODIS algorithm accurately quantified the LUE of alpine meadows on the Northern Tibetan Plateau.关键词
光能利用效率/高寒草甸/MODIS/藏北高原Key words
light use efficiency (LUE)/ alpine meadow/ MODIS/ Northern Tibetan Plateau分类
农业科技引用本文复制引用
付刚,沈振西,张宪洲,石培礼,何永涛,武建双,周宇庭..基于MODIS算法的藏北高寒草甸的光能利用效率模拟[J].草业学报,2012,21(1):239-247,9.基金项目
国家科技支撑计划项目(2007BAC06B01,2006BAC01A04).国家重点基础研究发展计划(2010CB833500)和国家自然基金项目(41171084,40771121)资助. （2007BAC06B01,2006BAC01A04）
