生态学报2017，Vol.37Issue(5)：1458-1471,14.DOI:10.5846/stxb201509281977
中国西北部草地植被降水利用效率的时空格局
Spatio-temporal patterns of precipitation-use efficiency of grassland in Northwestern
摘要
Abstract
Precipitation-use efficiency (PUE) is an important indicator used to determine how net primary productivity (NPP) responds to variation in precipitation,especially in arid and semi-arid ecosystems.The objective of this study was to determine the spatio-temporal patterns of PUE and its response to climatic factors along the precipitation gradient.The Carnegie-Ames-Stanford Approach (CASA) model was employed to simulate NPP in Inner Mongolia during 2001-2010 based on MOD13A1 data and spatially interpolated meteorological data.PUE was calculated as the ratio of NPP to annual precipitation.The results showed that:(1) The multi-year average PUE of grassland in Northwestern China was 0.68 g C m-2 mm-1.Among various type of temperate grassland,meadow steppe had the highest PUE,whereas the lowest PUE was found for desert.Furthermore,there were significant differences between the PUE of different grassland types.For the alpine grassland,alpine steppe had a higher PUE than alpine meadow.(2) Spatially,the PUE of temperate grassland increased first,peaking at ～ 472.9 mm/a,and then decreased with the precipitation gradient (R2=0.65,P＜0.001).The relationship between desert PUE and precipitation followed a similar trend (R2=0.63,P＜0.001),in which the highest PUE was found in the regions with annual precipitation of 263.2 mm.For the alpine meadow,PUE was low at both the dry (＞ 100 mm) and the wet ends of the annual precipitation gradient,and peaked around 559.2 mm (R2 =0.47,P ＜ 0.001).(3) Temporally,the inter-annual variation of PUE also responded differently to climatic factors in different precipitation ranges.In the area with precipitation of 200-1000 mm,PUE was positively correlated with precipitation.For the regions where precipitation was higher than 1050 mm,temperature had much greater effects than precipitation on the inter-annual variations of PUE.关键词
降水利用效率/植被覆盖度/温带草地/高寒草地/概念模型Key words
precipitation-use efficiency (PUE)/fraction of vegetation cover (FVC)/temperate grassland/alpine grassland/conceptual model引用本文复制引用
穆少杰,游永亮,朱超,周可新..中国西北部草地植被降水利用效率的时空格局[J].生态学报,2017,37(5):1458-1471,14.基金项目
江苏省自然科学青年基金资助项目(BK20140117) （BK20140117）
国家科技支撑计划课题资助项目(2012BAC01B08) （2012BAC01B08）
环保公益类资助项目(201409055) （201409055）
环境保护部“生物多样性保护专项”资助项目 （）
