气候变化领域集成服务门户(CCPortal): Polar-facing slopes showed stronger greening trend than equatorial-facing slopes in Tibetan plateau grasslands

CCPortal

DOI	10.1016/j.agrformet.2023.109698
	Polar-facing slopes showed stronger greening trend than equatorial-facing slopes in Tibetan plateau grasslands
	Yin, Gaofei; Yan, Xinyu; Ma, Dujuan; Xie, Jiangliu; Chen, Rui; Pan, Huiqin; Zhao, Wei; Wang, Changting; Verger, Aleixandre; Descals, Adria; Filella, Iolanda; Pen, Josep
发表日期	2023
ISSN	0168-1923
EISSN	1873-2240
卷号	341
英文摘要	The orientation of slopes in alpine zones creates microclimates, e.g. equatorial-facing slopes (EFSs) are generally drier and warmer than are polar-facing slopes (PFSs). The vegetation growing in these microhabitats responds divergently to climatic warming depending on the slope orientation. We proposed a spatial metric, the greenness asymmetric index (GAI), defined as the ratio between the average normalized difference vegetation index (NDVI) on PFSs and EFSs within a given spatial window, to quantify the asymmetry of greenness across aspects. We calculated GAI for each non-overlapping 3 x 3 km(2) (100 x 100 Landsat pixels) grid, and seamlessly mapped it on Tibetan Plateau (TP) grassland using NDVI time series from the Landsat-5, -7 and -8 satellites. PFSs were greener than EFSs (GAI > 1) in warm and dry areas, and EFSs were greener than PFSs (GAI < 1) in cold and wet areas. We also detected a stronger greening trend (0.0040 vs 0.0034 y(-1)) and a higher sensitivity of NDVI to temperature (0.031 vs 0.026 C-degrees(-1)) on PFSs than EFSs, leading to a significant positive trend in GAI (0.00065 y(-1), P < 0.01) in the TP from 1991 to 2020. Our results suggest that global warming exacerbated the greenness asymmetry associated with the slope orientation: PFSs are more sensitive to warming and have been greening at a faster rate than EFSs. The gradient of EFSs and PFSs provided a natural laboratory to study interaction of water and temperature limitations on vegetation growth. Our study is the first to detect the effect of aspect on the greening trend in the TP. Future research needs to clarify the full biotic and abiotic determinants for this spatial and temporal asymmetry of greenness across aspects with the support of extensive field measurements and refined high-resolution NDVI products.
关键词	Aspect gradient Greenness asymmetry Climatic warming Microclimate Greening Tibetan plateau
英文关键词	PRODUCTIVITY; CLIMATE; PRECIPITATION; TEMPERATURE; ECOSYSTEMS; LANDSAT-7; PHENOLOGY; EXCHANGE; DROUGHT; REGIONS
WOS研究方向	Agronomy ; Forestry ; Meteorology & Atmospheric Sciences
WOS记录号	WOS:001084423800001
来源期刊	AGRICULTURAL AND FOREST METEOROLOGY
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/283877
作者单位	Southwest Jiaotong University; Chinese Academy of Sciences; Institute of Mountain Hazards & Environment, CAS; Southwest Minzu University; Consejo Superior de Investigaciones Cientificas (CSIC); University of Valencia; CSIC-GV-UV - Centro de Investigaciones sobre Desertificacion (CIDE); Centro de Investigacion Ecologica y Aplicaciones Forestales (CREAF-CERCA); Consejo Superior de Investigaciones Cientificas (CSIC); Centro de Investigacion Ecologica y Aplicaciones Forestales (CREAF-CERCA)
推荐引用方式 GB/T 7714	Yin, Gaofei,Yan, Xinyu,Ma, Dujuan,et al. Polar-facing slopes showed stronger greening trend than equatorial-facing slopes in Tibetan plateau grasslands[J],2023,341.
APA	Yin, Gaofei.,Yan, Xinyu.,Ma, Dujuan.,Xie, Jiangliu.,Chen, Rui.,...&Pen, Josep.(2023).Polar-facing slopes showed stronger greening trend than equatorial-facing slopes in Tibetan plateau grasslands.AGRICULTURAL AND FOREST METEOROLOGY,341.
MLA	Yin, Gaofei,et al."Polar-facing slopes showed stronger greening trend than equatorial-facing slopes in Tibetan plateau grasslands".AGRICULTURAL AND FOREST METEOROLOGY 341(2023).