Journal Article

Basin-wide impacts of climate change on ecosystem services in the Lower Mekong Basin

Johnston, John M., Aekakkararungroj, Aekkapol, Ma, Hwan-ok, Trisurat, Yongyut

2018

Overview

Water resources support more than 60 million people in the Lower Mekong Basin (LMB) and are important for food security—especially rice production—and economic security. This study aims to quantify water yield under near- and long-term climate scenarios and assess the potential impacts on rice cultivation. The InVEST model (Integrated Valuation of Ecosystem Services and Tradeoffs) forecasted water yield, and land evaluation was used to delineate suitability classes. Pattern-downscaled climate data were specially generated for the LMB. Predicted annual water yields for 2030 and 2060, derived from a drier overall scenario in combination with medium and high greenhouse gas emissions, indicated a reduction of 9–24% from baseline (average 1986–2005) runoff. In contrast, increased seasonality and wetter rainfall scenarios increased annual runoff by 6–26%. Extreme drought decreased suitability of transplanted rice cultivation by 3%, and rice production would be reduced by 4.2 and 4%, with and without irrigation projects, relative to baseline. Greatest rice reduction was predicted for Thailand, followed by Lao PDR and Cambodia, and was stable for Vietnam. Rice production in the LMB appears sufficient to feed the LMB population in 2030, while rice production in Lao PDR and Cambodia are not expected to be sufficient for domestic consumption, largely due to steep topography and sandy soils as well as drought. Four adaptation measures to minimize climate impacts (i.e., irrigation, changing the planting calendar, new rice varieties, and alternative crops) are discussed.

• Publisher: Springer Japan,Blackwell Publishing Ltd
• Subject: Adaptation / Alternative crops / Annual / Annual rainfall / Annual runoff / basins / Behavioral Sciences / Biomedical and Life Sciences / Cambodia / Climate / Climate change / Climatic data / Crop production / Cultivation / Drought / Ecology / Ecosystem services / Ecosystems / Environmental changes / Environmental impact / Evaluation / Evolutionary Biology / Extreme drought / Food security / Forestry / Grain cultivation / Greenhouse effect / greenhouse gas emissions / Greenhouse gases / Irrigation / land evaluation / Laos / Life Sciences / Lower Mekong Basin / Mekong River / meteorological data / people / Plant Sciences / planting / Rain / Rainfall / Reduction / Rice / Rice cultivation / Runoff / Sandy soils / Seasonal variations / Seasonality / Security / Slope / Soil / Special Feature: Original Article / Thailand / Topography / Topography (geology) / Vietnam / Water resources / Water yield / Zoology