生态与农村环境学报2017，Vol.33Issue(12)：1102-1108,7.DOI:10.11934/j.issn.1673-4831.2017.12.006
西藏雅鲁藏布江流域植物物候变化及其海拔效应
Changes in Vegetation Phenology and Its Elevation-Dependent Effects in the Yarlung Zangbo River Valley of Ti-bet, China
摘要
Abstract
The Yarlung Zangbo River Valley ( YZR) , stretching across the southern part of the Tibetan Plateau from west to east over a wide range of elevation from 147 m to over 7000 m above sea level (a.s.l.) with an average elevation of 4600 m, has been regarded as one of the ideal regions for the study on ecological response to climate change in alpine water-shed. Based on the datasets of SPOT-VGT normalized difference vegetation index ( NDVI) and SRTM digital elevation model ( DEM) , phonological features of the valley were extracted and elevation-dependent phenological change of the veg-etation of the YZR during 1999-2013 was analyzed. The SPOT-VGT NDVI was first preprocessed with the non-symmetri-cal Gaussian function ( AG) fitting method, and then the start date of growing season ( SOG) , the end date of the growing season (EOG) and the length of the growing season (LOG) of the vegetation was extracted, separately, through the threshold value method. Results show:( 1) The SOG exhibited an advancing trend in 61. 3% of the YZR, and a delaying trend in 38. 8%, while the EOG did an advancing trend in 45. 3% and a delaying trend in 54. 7%. As a consequence, the LOG in the YZR was shortening, with the annual changing rate per pixel being-0. 47 d·a-1;( 2) The SOG was gradual-ly delaying, the EOG gradually advancing and the LOG gradually shortening along the river from the downstream up to the upstream. Besides, LOG and its annual changing rate is generally on a declining trend with rising elevation.关键词
植物物候/海拔效应/遥感技术/高海拔地区/青藏高原Key words
vegetation phenology/elevation-dependent effects/remote sensing technology/alpine regions/Tibetan Plat-eau分类
资源环境引用本文复制引用
李海东,陈斌,叶尔纳尔·胡马尔汗,曹学章..西藏雅鲁藏布江流域植物物候变化及其海拔效应[J].生态与农村环境学报,2017,33(12):1102-1108,7.基金项目
中央级公益性科研院所基本科研业务专项( GYZX170201) （ GYZX170201）
西藏山南生态监测站2017年度监测任务项目 （）
国家自然科学基金(41301611) （41301611）
