干旱地区农业研究2011，Vol.29Issue(1)：257-263,7.
近10年甘南牧区草地净初级生产力变化研究
Research on changes of net primary productivity of grassland vegetation in Gannan pastoral area over the past 10 years
摘要
Abstract
An improved CASA model with MODIS NDVI along with meteorological data was used to estimate the net primary productivity (NPP) of grassland vegetation in pasture season in July each year in 2000, 2005 and 2008, and to analyse its spatial and temporal dynamics. The results showed that: (1) The fundamental spatial pattern of annual NPP in Gannan pastoral was characterized by low NPP levels distributed in the west-southwest and northwest corners, then the NPP levels increased gradually from the two comers into the arid inland regions. This distribution was bound up with different hydrothermal conditions and variation of zonal of vegetation. In addition, it was significantly different between the average NPP of grassland vegetation in July and the total NPP of grassland vegetation in July, which was closely related to each county area. The sequence of the value of average NPP of grassland vegetation in July in each county was Luqu ＞Maqu ＞ Hezuo ＞ Xiahe, while the sequence of the value of total NPP of grassland vegetation in July in each county was Maqu ＞ Xiahe ＞ Luqu ＞ Hezuo. (2) The value of NPP of grassland vegetation in July of 2008 was much smaller than that of 2000. From 2000 ～ 2008, the NPP of grassland vegetation of the entire study area in July increased first, and then decreased. The main reason was the changes of temperature, precipitation and wettability, while wettability change was a major limiting factor to affect the growth of pasture in Gannan plateau.关键词
改进CASA模型/植被净初级生产力/甘南牧区Key words
improved CASA model/ change of grassland NPP/ correlation/ Gannan pastoral area分类
农业科技引用本文复制引用
杨东辉,赵军,张智慧,付鹏,刘春雨..近10年甘南牧区草地净初级生产力变化研究[J].干旱地区农业研究,2011,29(1):257-263,7.基金项目
国家自然科学基金项目(40961026) （40961026）
甘肃省自然科学基金项目(0803RJZA088) （0803RJZA088）
