Risk and vulnerability of Mongolian grasslands under climate change
Open Access
- 13 January 2021
- journal article
- research article
- Published by IOP Publishing in Environmental Research Letters
- Vol. 16 (3), 034035
- https://doi.org/10.1088/1748-9326/abdb5b
Abstract
Climate change is projected to increase the aridity of semi-arid ecosystems, including Mongolian grasslands (MG), which provide ecosystem services that support food supply and pastoralist lifestyle. Here, we conducted a grid-scale (0.5º×0.5º) probabilistic risk assessment of MG under climate change for 40 years (1976–2015) based on probability theory. We evaluated changes of risk (impacts) and vulnerability of MG to drought between the recent two decades R20 = 1996–2015 and the previous two decades P20 = 1976–1995. The risk is quantified as the product of the probability of hazardous drought and ecosystem vulnerability. The probability of hazardous drought is defined from the Standardized Precipitation–Evapotranspiration Index. Vulnerability is defined as the expected differences of key ecosystem variables between years with and without hazardous conditions. The ecosystem variables are productivity (peak aboveground biomass, net primary productivity, and leaf area index) and root-zone plant-available soil moisture, simulated with a process-based vegetation model ORCHIDEE-GM validated with field observations of biomass and soil moisture. Results reveal that MG experienced more frequent hazardous droughts with rapid warming and slight drying during R20 aggravated by ever-increasing grazing intensity (34% compared to P20), which resulted in a reduction in soil water availability and grassland productivity, particularly in northeastern areas (20−65%). The risk of drought to productivity increased by 10% between P20 and R20 over extended areas, particularly in northcentral and northeast Mongolia. The increase in the risk to MG was mainly caused by climate change-induced increase in the probability of hazardous drought and, to a lesser extent, by the increasing vulnerability. Recent droughts modify the risk to grasslands, particularly in northcentral and northeast Mongolia, suggesting that these regions need strategic management for both adaptation and ecosystem conservation to cope with climate change impacts.Keywords
Funding Information
- National University of Mongolia (Research Fellowship Grant: P2017-2504)
- Taylor Family-Asia Foundation (Endowed Chair in Ecology and Conservation Biology)
- Daiko Foundation (1019789)
This publication has 64 references indexed in Scilit:
- Changing Climate and Overgrazing Are Decimating Mongolian SteppesPLOS ONE, 2013
- Grassland Resistance and Resilience after Drought Depends on Management Intensity and Species RichnessPLOS ONE, 2012
- Using prior information to build probabilistic invasive species risk assessmentsBiological Invasions, 2011
- Dry Times AheadScience, 2010
- Impact of drought on vegetation dynamics of the Mongolian steppe: A field experimentJournal of Arid Environments, 2010
- Towards a Formal Framework of Vulnerability to Climate ChangeEnvironmental Modeling & Assessment, 2008
- A climate-change risk analysis for world ecosystemsProceedings of the National Academy of Sciences of the United States of America, 2006
- A dynamic global vegetation model for studies of the coupled atmosphere‐biosphere systemGlobal Biogeochemical Cycles, 2005
- C 4 plants in the vegetation of Mongolia: their natural occurrence and geographical distribution in relation to climateOecologia, 2000
- Developing joint probability distributions of soil water retention characteristicsWater Resources Research, 1988