Climate change impact assessment on three major crops in the north-central region of Bangladesh using DSSAT

Atikur Rahman,Mohammad Abdul Mojid,Selina Banu

doi:10.25165/j.ijabe.20181103.3331

Abstract

The potential consequences of climate change emanated from global warming are very alarming; the greatest concern is the potentially disastrous consequences on crop agriculture and food security in many parts of the world. Bangladesh is a country highly susceptible to climate change, but information in this regard is still inadequate. This study investigated the effects of climate change on three major crops – wheat, potato and rice – in the north-central region of Bangladesh. Two climate change scenarios, A2 and B2, of the Intergovernmental Panel on Climate Change (IPCC) were generated by employing MAGICC/SCENGEN model together with the observed climate data of the region. The growth and yield of the crops were simulated using DSSAT CERES-Wheat, SUBSTOR-Potato and CERES-Rice models under the present and projected future changing climatic conditions. For a predicted 5.32ºC increase in temperature in the year 2100, the yield of wheat, rice and potato would decrease by 47.6%, 67.8% and 38.6%, respectively. The increased temperature would accelerate physiological maturity of the crops as reflected by their reduced length of growing season (LGS) by 1.20% to 18.5%. The reduced LGS would reduce seasonal evapotranspiration (ET) of the crops by shortening time-span for ET generation. Due to dominant yield reduction over ET reduction, the water use efficiency (WUE) for grain/tuber and biomass yields would decrease with the changing climate. The reduced crop yields are an indicative of a potential future risk of food security in Bangladesh. The results of this study can therefore guide to adopt coping mechanisms in the light of climate change to ensure future food security of the country. Keywords: climate change, DSSAT, MAGICC/SCENGEN model, CERES model, SUBSTOR model, growing season length, crop-water use DOI: 10.25165/j.ijabe.20181104.3331 Citation: Rahman A, Mojid M A, Banu S. Climate change impact assessment on three major crops in the north-central region of Bangladesh using DSSAT. Int J Agric & Biol Eng, 2018; 11(4): 135-143.

Highlights

Data used for model calibration were collected from several experiments that were conducted previously in Bangladesh Agricultural University (BAU) Research Farm at Mymensingh in Bangladesh
Most of the rainfalls were concentrated in the months of April to October
Precipitation would increase, except in the months of April to June; the increase would be higher during October to February than in the other months

Summary

Introduction

The current population of Bangladesh is 156 million[1], with one of the highest densities (1015 persons/km2) in the world, and the population of the country is still growing at 1.37% per year This rate is expected to slow down in future, most projections estimated a 200 million population by 2050[2]. This would mean a more than 25% increase in the demand for food grains. Rice being the principal grain crop accounts for 77% of agricultural land use and contributes half of the agricultural GDP and one-sixth of the national income. There remains hardly any scope for bringing new lands under cultivation, while the country is losing 80 000 hm of arable land every year[6] due to housing and settlement, building physical infrastructures, river erosion and various other non-agricultural uses

Methods

Results

Conclusion