北京林业大学学报2018，Vol.40Issue(3)：75-83,9.DOI:10.13332/j.1000-1522.20170298
毛乌素沙地油蒿群落叶面积指数动态及模拟
Dynamics and simulation of leaf area index for Artemisia ordosica community in the Mu Us Desert of northwestern China
摘要
Abstract
[ Objective] Our objective here was to rapidly and accurately obtain long-term continuous LAI for Artemisia ordosica communities in the Mu Us Desert of northwestern China, which is of great importance for understanding the relationship between ecosystem processes and environmental changes. [ Method] We measured LAI in a typical A. ordosica community using the LAI-2000 canopy analyzer (LI-COR, USA) from April to October in the growing season of 2013 and 2014, and obtained MODIS NDVI ( NDVIMODIS ) data for the same periods. Ground-based NDVI ( NDVIground ) was calculated from incident and reflected solar radiation and photosynthetically active radiation, which were measured by radiation sensors mounted on a tower in the center of the community. LAI measurements were used to examine seasonal changes and construct LAI models. Normalized effective accumulated temperature, NDVIground and NDVIMODIS were used to construct optimal LAI model for the community. [ Result] The seasonal dynamics was consistent with the phenophases of A. ordosica and showed a hump-shaped pattern. LAI increased from April to late August, reached a peak in August (1. 09 and 1. 33 m2/m2 in 2013 and 2014, respectively), remained relatively stable from early September to mid-September, and rapidly declined from late September due to the defoliation of A. ordosica. The optimal LAI model was NDVIground(R2 =0. 76,P <0. 01). [Conclusion] Our results indicate that long-term continuous LAI estimates for A. ordosica communities in the Mu Us Desert can be easily obtained using NDVI measurements and the model. The model can be used to understand and predict ecological impacts of climate change.关键词
油蒿/叶面积指数/积温/NDVIKey words
Artemisia ordosica/leaf area index/accumulated temperature/NDVI分类
农业科技引用本文复制引用
张财,查天山,贾昕,刘鹏,李成..毛乌素沙地油蒿群落叶面积指数动态及模拟[J].北京林业大学学报,2018,40(3):75-83,9.基金项目
国家自然科学基金项目(31670710、31670708),中央高校基本科研业务费专项(2015ZCQ-SB-02). （31670710、31670708）
