Declining trends of water requirements of dry season Boro rice in the north-west Bangladesh

Author

Tapos Kumar Acharjee, Gerardo van Halsema, Fulco Ludwig and Petra Hellegers

Agricultural Water Management, 2017, vol. 180, issue PA, pages 148-159

Abstract: The drought prone North-West Bangladesh is vulnerable to the impacts of climate change, particularly because of less water availability in the dry period and high water requirement for crop production. Improved understanding of recent changes in crop water demand in the dry season is important for the water resources management in the region. A study was carried out to determine the potential impacts of recent climate change during last three decades on trends of water requirements of Boro rice. The reference crop evapotranspiration (ETo), potential crop water requirement (∑ETC), effective rainfall during the crop growing period (ER), potential irrigation requirement for crop evapotranspiration (∑ETC−ER) and net irrigation requirement of Boro rice were estimated using observed daily climate data in the CropWat model for the period of 1980 to 2013 for four North-West districts. Significant decreasing trends of ETo were observed in most of the dry months due to increasing relative humidity and decreasing wind-speed and sun-shine hours. The results showed decreasing trends of potential crop water requirement, i.e. the total crop evapotranspiration (∑ETC), of Boro rice due to decreasing reference crop evapotranspiration and shorter crop growing periods. The variations in trends of potential irrigation requirement for crop evapotranspiration (∑ETC−ER) found among different districts, are mainly linked to variations in trends of changes in effective rainfall. The net irrigation requirement of Boro rice has decreased, by 11% during the last three decades at an average rate of −4.4mmyear−1, instead of decreasing effective rainfall, mainly because of high rate of decrease of crop evapotranspiration (−5.9mmyear−1). Results indicate that a warming climate does not always result in higher agricultural water use and that climate change can also result in reduced water demands because of changes in humidity, wind-speed and sun-shine hours.

Keywords: Water demand; Evapotranspiration; Climate change (search for similar items in EconPapers)
Date: 2017
References: View references in EconPapers View complete reference list from CitEc
Citations Track citations by RSS feed

Downloads: (external link)
http://www.sciencedirect.com/science/article/pii/S0378377416304577
Full text for ScienceDirect subscribers only

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link:http://EconPapers.repec.org/RePEc:eee:agiwat:v:180:y:2017:i:pa:p:148-159

Access Statistics for this article

Agricultural Water Management is currently edited by B.E. Clothier, W. Dierickx, J. Osterand D. Wichelns

More articles in Agricultural Water Management from  Elsevier
Series data maintained by Dana Niculescu (repec@elsevier.com).

For further details log on website :
http://econpapers.repec.org/article/eeeagiwat/v_3a180_3ay_3a2017_3ai_3apa_3ap_3a148-159.htm