生态学报2017，Vol.37Issue(13)：4335-4345,11.DOI:10.5846/stxb201408291724
1982-2010年中国草地净初级生产力时空动态及其与气候因子的关系
Spatio-temporal dynamics of grassland net primary productivity and their relationship with climatic factors from 1982 to 2010 in China
摘要
Abstract
Global warming has led to significant vegetation changes in the past half century.Grasslands in China are mainly located in ecologically fragile regions,which are sensitive to climate change.During recent decades,grasslands have experienced prominent warming and drying.Therefore,investigating the response of grasslands to climatic variations is necessary for a better understanding of the cumulative consequences of climate change.Grassland net primary productivity (NPP) is an important indicator for evaluating grassland ecosystem conditions.We used multi-source remote-sensing data and meteorological data to estimate the grassland NPP from 1982 to 2010,based on the Carnegie-Ames-Stanford approach (CASA) model.The spatial pattern and change trends of grassland NPP were evaluated.The response of grassland NPP changes to climatic variations was also analyzed.The results revealed that the spatial distribution of grassland NPP showed an increasing trend from the northwest to southeast across China.During the period from 1982 to 2010,the grassland mean NPP was 282 gC m-2a-1,and NPP exhibited apparent spatial heterogeneity,being highest (710 gC m-2a-1) in the dry heat savanna shrub and grass and lowest (58 gC m-2a-1) in the alpine desert.The total annual NPP was 988.3 Tg C.Grassland NPP has increased slightly in the past 30 years,at a rate of 0.6 gC m-2a-1.Regions showing increasing NPP accounted for 67.2％ of the total grassland areas,within which,areas with extremely significant (P＜0.01) and significant (P＜0.05) increases accounted for 35.8％ and 8.0％ of the total grassland area,respectively.Regions showing extremely significant and significant decreases encompassed only 5.8％ and 4.8％ of total grassland area,respectively.Clear increases in grassland NPP were observed in the west of the Qinghai-Tibet Plateau,the Alxa Plateau and western area of Xinjiang.Areas with a decrease in grassland NPP were mainly distributed in the western regions of Inner Mongolia.Furthermore,the increasing rate of NPP showed temporal variation and differed among different grassland types.The correlation coefficient between NPP and precipitation was larger than that between NPP and temperature.Moreover,the response of grassland NPP to temperature and precipitation differed for different grassland types.There were significant positive correlations between annual precipitation and NPP in temperate desert steppe,temperate steppe,and temperate meadow steppe.关键词
草地净初级生产力/时空动态/气温/降水量/耦合关系分析Key words
grassland net primary productivity/spatio-temporal dynamics/temperature/precipitation/the coupling relation analysis引用本文复制引用
周伟,牟凤云,刚成诚,官冬杰,何锦峰,李建龙..1982-2010年中国草地净初级生产力时空动态及其与气候因子的关系[J].生态学报,2017,37(13):4335-4345,11.基金项目
国家自然科学基金(41501575,41501202) （41501575,41501202）
重庆市科委基础科学与前沿技术项目(cstc2016jcyjA1540,cstc2014jcyjA0808) （cstc2016jcyjA1540,cstc2014jcyjA0808）
重庆交通大学博士科研启动金(14JDKJC-B017) （14JDKJC-B017）
