Vegetation dynamics and responses to climate change and human activities in Central Asia

被引:485
作者
Jiang, Liangliang [1 ,2 ]
Jiapaer, Guli [1 ]
Bao, Anming [1 ]
Guo, Hao [1 ,2 ]
Ndayisaba, Felix [1 ,2 ]
机构
[1] Chinese Acad Sci, State Key Lab Desert & Oasis Ecol, Xinjiang Inst Ecol & Geog, Urumqi 830011, Peoples R China
[2] Univ Chinese Acad Sci, Beijing 100049, Peoples R China
基金
中国国家自然科学基金;
关键词
Vegetation dynamics; NDVI; Climatic change; Human activities; Hurst exponent; PRECIPITATION; COVER; TEMPERATURE; IMPACTS; DISCRIMINATION; DEGRADATION; DROUGHT; DESERT; TRENDS; GROWTH;
D O I
10.1016/j.scitotenv.2017.05.012
中图分类号
X [环境科学、安全科学];
学科分类号
08 ; 0830 ;
摘要
Knowledge of the current changes and dynamics of different types of vegetation in relation to climatic changes and anthropogenic activities is critical for developing adaptation strategies to address the challenges posed by climate change and human activities for ecosystems. Based on a regression analysis and the Hurst exponent index method, this research investigated the spatial and temporal characteristics and relationships between vegetation greenness and climatic factors in Central Asia using the Normalized Difference Vegetation Index (NDVI) and gridded high-resolution station (land) data for the period 1984-2013. Further analysis distinguished between the effects of climatic change and those of human activities on vegetation dynamics by means of a residual analysis trend method. The results show that vegetation pixels significantly decreased for shrubs and sparse vegetation compared with those for the other vegetation types and that the degradation of sparse vegetation was more serious in the Karakum and Kyzylkum Deserts, the Ustyurt Plateau and the wetland delta of the Large Aral Sea than in other regions. The Hurst exponent results indicated that forests are more sustainable than grasslands, shrubs and sparse vegetation. Precipitation is the main factor affecting vegetation growth in the Kazakhskiy Melkosopochnik. Moreover, temperature is a controlling factor that influences the seasonal variation of vegetation greenness in the mountains and the Aral Sea basin. Drought is the main factor affecting vegetation degradation as a result of both increased temperature and decreased precipitation in the Kyzylkum Desert and the northern Ustyurt Plateau. The residual analysis highlighted that sparse vegetation and the degradation of some shrubs in the southern part of the Karakum Desert, the southern Ustyurt Plateau and the wetland delta of the Large Aral Sea were mainly triggered by human activities: the excessive exploitation of water resources in the upstream areas of the Amu Darya basin and oil and natural gas extraction in the southern part of the Karakum Desert and the southern Ustyurt Plateau. The results also indicated that after the collapse of the Soviet Union, abandoned pastures gave rise to increased vegetation in eastern Kazakhstan, Kyrgyzstan and Tajikistan, and abandoned croplands reverted to grasslands in northern Kazakhstan, leading to a decrease in cropland greenness. Shrubs and sparse vegetation were extremely sensitive to short-term climatic variations, and our results demonstrated that these vegetation types were the most seriously degraded by human activities. Therefore, regional governments should strive to restore vegetation to sustain this fragile arid ecological environment (C) 2017 Elsevier B.V. All rights reserved.
引用
收藏
页码:967 / 980
页数:14
相关论文
共 65 条
[1]  
[Anonymous], 2015, LAND USE COVER CHANG
[2]  
[Anonymous], ARAL SEA DEVASTATION
[3]  
[Anonymous], EMD CORRECTION ORBIT
[4]  
[Anonymous], CLIMATE CHANGE 2007
[5]  
[Anonymous], EURO J REM SENS
[6]  
[Anonymous], PLANT LIFE DOLOM SPR
[7]  
[Anonymous], REMOTE SENS REV
[8]   Regional vegetation die-off in response to global-change-type drought [J].
Breshears, DD ;
Cobb, NS ;
Rich, PM ;
Price, KP ;
Allen, CD ;
Balice, RG ;
Romme, WH ;
Kastens, JH ;
Floyd, ML ;
Belnap, J ;
Anderson, JJ ;
Myers, OB ;
Meyer, CW .
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 2005, 102 (42) :15144-15148
[9]  
Chatfield C, 2016, ANAL TIME SERIES INT
[10]  
Cohen J, 2014, NAT GEOSCI, V7, P627, DOI [10.1038/ngeo2234, 10.1038/NGEO2234]