Impact of Future Climate Change on Regional Crop Water Requirement—A Case Study of Hetao Irrigation District, China

Tianwa Zhou,Xiaolei Li,Xiaobo Luan,Shikun Sun,Yubao Wang,Pute Wu

doi:10.3390/w9060429

Abstract

Water shortage is a limiting factor for agricultural production in China, and climate change will affect agricultural water use. Studying the effects of climate change on crop irrigation requirement (CIR) would help to tackle climate change, from both food security and sustainable water resource use perspectives. This paper applied SDSM (Statistical DownScaling Model) to simulate future meteorological parameters in the Hetao irrigation district (HID) in the time periods 2041–2070 and 2071–2099, and used the Penman–Monteith equation to calculate reference crop evapotranspiration (ET0), which was further used to calculate crop evapotranspiration (ETc) and crop water requirement (CWR). CWR and predicted future precipitation were used to calculate CIR. The results show that the climate in the HID will become warmer and wetter; ET0 would would increase by 4% to 7%; ETc and CWR have the same trend as ET0, but different crops have different increase rates. CIR would increase because of the coefficient of the increase of CWR and the decrease of effective precipitation. Based on the current growing area, the CIR would increase by 198 × 106 to 242 × 106 m3 by the year 2041–2070, and by 342 × 106 to 456 × 106 m3 by the years 2071–2099 respectively. Future climate change will bring greater challenges to regional agricultural water use.

Highlights

According to the Assessment Report 5 of the Intergovernmental Panel on Climate Change (IPCC), the global surface temperature has increased by 0.65–1.06 ◦ C during the years 1880–2012, and the rate of the temperature increase after 1951 has been approximately 0.12 ◦ C per 10 years, which is almost twice the rate since 1880
Exploring the changes in crop water requirement (CWR) and crop irrigation requirement (CIR) under the climate change circumstance could provide a theoretical basis for the design of irrigation water conservation facilities and agricultural water resources management
The generalized linear model (GLM) was used in reference [15] to estimate the future ET0 in the UK, and the results indicate that the southern part of the UK will be more sensitive to the change in ET0 than the north

Summary

Introduction

According to the Assessment Report 5 of the Intergovernmental Panel on Climate Change (IPCC), the global surface temperature has increased by 0.65–1.06 ◦ C during the years 1880–2012, and the rate of the temperature increase after 1951 has been approximately 0.12 ◦ C per 10 years, which is almost twice the rate since 1880. Climate change could affect global food production and supply [3], but can impact the quality and safety of agricultural products [4,5]. The world’s Food and Agriculture Organization (FAO) has made it a worldwide challenge to cope with climate change when solving world’s food supply problem and relieving hunger [6]. Climate change would have impacts on crop growth and water consumption pattern, as well as the quantity of irrigation water that crops. Exploring the changes in crop water requirement (CWR) and crop irrigation requirement (CIR) under the climate change circumstance could provide a theoretical basis for the design of irrigation water conservation facilities and agricultural water resources management

Results

Discussion

Conclusion