| Title: | The spatial-temporal variation characteristics of natural vegetation drought in the Yangtze River Source Region, China |
| Authors: | Yin, J., Z. Yuan and T. Li |
| Year: | 2021 |
| Journal: | International Journal of Environmental Research and Public Health |
| Volume (Issue): | |
| Pages: | |
| Article ID: | 1613 |
| DOI: | 10.3390/ijerph18041613 |
| URL (non-DOI journals): | |
| Model: | SWAT |
| Broad Application Category: | hydrologic only |
| Primary Application Category: | blue, green and/or gray water, or crop water productivity |
| Secondary Application Category: | hydrologic assessment |
| Watershed Description: | 159,065 km^2 Yangtze River Source Region, located in the western Tibetan Plateau in west central China. |
| Calibration Summary: | |
| Validation Summary: | |
| General Comments: | The authors state that the SWAT model used in this study was developed in the following previous study: Zhang, W., X. Zha, J. Li, W. Liang, Y. Ma, D. Fan and S. Li. 2014. Spatiotemporal change of blue water and green water resources in the headwater of Yellow River Basin, China. Water Resources Management. 28(13): 4715-4732. Doi: 10.1007/s11269-014-0769-x. |
| Abstract: | In the context of climate change, ecosystem in Yangtze River Source Region (YRSR) is under threat from severe droughts. This study introduced a new natural vegetation drought index, standardized supply-demand water index (SSDI), and identified natural vegetation drought events and parameters (e.g., duration, severity, peak, and coverage area) based on run theory. Then the drought-prone regions were investigated via 2-dimensional joint copula. The results indicate that (1) compared with traditional meteorological drought index, the SSDI is reliable and can reflect the comprehensive characteristics of the ecological drought information more easily and effectively; (2) the YRSR had witnessed the most severe drought episodes in the periods of late-1970s, mid-1980s, and mid-1990s, but the SSDI showed a wetting trend since the mid-2000s. Additionally, droughts in the Southern YRSR were relatively more severe with longer drought duration; (3) in most areas of Togton River Basin and Dam River Basin, the severe ecological drought events occurred more frequently; (4) drought duration and severity in the YRSR were more susceptible to temperature when the temperature rise was above 1.0 ◦C. The average drought duration and severity increased by 20.7% and 32.6% with a temperature rise of 1 ◦C. Investigating and evaluating drought characteristics, causes, and drought index effectiveness provide essential information for balanced water resource allocation, utilization, and drought prevention. Understanding these spatial-temporal characteristics of drought and return period was useful for drought risk assessment and sustainable development of water resources. |
| Language: | English |
| Keywords: | ecological drought; spatial-temporal characteristics; probability and return period; Yangtze River Source Region |