Climate change impacts on the suitability of lowland and upland crop systems in Lao PDR
Jonas L. Appelt, Thatheva Saphangthong, Peter H. Verburg, Jasper van Vliet
Abstract
CONTEXT Climate change is a major driver of changes in agricultural systems, with effects playing out differently across crop types and biophysical conditions. Studies have so far not investigated differences between lowland and upland crop systems when projecting consequences of climate change on agricultural production in Southeast Asia. OBJECTIVE To model the change in crop suitability under different climate scenarios for major crops in Lao PDR and analyse differentiated impacts across lowland and upland crop systems. METHODS We use a modified version of the EcoCrop suitability model, adding additional considerations for precipitation seasonality , to project the change in crop suitability in Lao PDR under different climate scenarios for the medium term future (2041–2070). The analysis compares impacts across lowland and upland village areas for six major crops: Paddy rice, upland rice, maize, cassava, banana, and rubber. Further, we contextualize the results with data from a survey of eight lowland and four upland villages in Savannakhet Province. RESULTS AND CONCLUSIONS For all the included crops, we find that changes in climatic suitability will be significantly more negative (higher decrease or smaller increase) in lowland village areas than in upland village areas. In particular, rice suitability is projected to decrease considerably in lowland areas due to increases in heat and variability in wet season precipitation, while higher temperatures improve the suitability of non-rice crops in upland areas due to lower cold stress, with the largest increases being for maize, cassava, and banana. Local crop data from Savannakhet Province further reveals how climate change impacts can increase the risks to production and food security in rice focused systems in lowland areas. SIGNIFICANCE These results indicate that upland crop systems in Lao PDR may fare better than lowland systems under future climate change and highlight the importance of differentiating between agricultural production systems when projecting impacts of climate change in Southeast Asia.