Assessment of Potential Climate Change Effects on the Rice Yield and Water Footprint in the Nanliujiang Catchment, China

Abstract

Abstract:The Nanliujiang catchment is one of major rice production bases of South China. Irrigation districts play an important role in rice production which requires a large quantity of water. There are potential risks on future climate change in response to rice production, agricultural irrigation water use and pollution control locally. The SWAT model was used to quantify the yield and water footprint (WF) of rice in this catchment. A combined method of automatic and manual sub-basin delineation was used for the model setup in this work to reflect the differences between irrigation districts in yield and water use of rice. We validated our simulations against observed leaf area index, biomass and yield of rice, evapotranspiration and runoff. The outputs of three GCMs (GFDL-ESM2M, IPSL-CM5A-LR and HadGEM2-ES) under three RCPs (RCP2.6, 4.5, 8.5) were fed to the SWAT model. The results showed that: (a) the SWAT model is an ideal tool to simulate rice development as well as hydrology; (b) there would be increases in rice yield ranged from +1.4 to +10.6% under climate projections of GFDL-ESM2M and IPSL-CM5A-LR but slight decreases ranged from −3.5 to −0.8% under that of HadGEM2-ES; (c) the yield and WFs of rice displayed clear differences in the catchment, with a characteristic that high in the south and low in the north, mainly due to the differences in climatic conditions, soil quality and fertilization amount; (d) there would be a decrease by 45.5% in blue WF with an increase by 88.1% in green WF, which could provide favorable conditions to enlarge irrigated areas and take technical measures for improving green water use efficiency of irrigation districts; (e) a clear rise in future grey WF would present enormous challenges for the protection of water resources and environmental pollution control in this catchment. So it should be to improved nutrient management strategies for the agricultural non-point source pollution control in irrigation districts, especially for the Hongchaojiang and Hepu irrigation districts.

Performance of rice paddy varieties under various organic soil fertility strategies

“…Global warming significantly impacts precipitation patterns and plant growth parameters, which in turn exacerbate agricultural productivity. To secure food particularly rice for the growing population, additional pressure on agriculture resources is expected (Yang et al 2018). National rice production can be reduced by adverse climatic and environmental conditions (Padukkage et al 2017).…”

Impact of Future Climate Change on Wheat Production: A Simulated Case for China’s Wheat System

“…So far, the extent of yield loss resulting from future climate change in any one particular region still remains unclear [12]. While Global Climate Models (GCMs) can be used to project future climatic conditions [13], crop models can also be used to simulate crop growth processes and yields [14]. It is therefore possible to assess the impact of future climate change on crop production through the joint use of GCMs and crop models [15,16].…”

Assessing water scarcity in Malaysia: a case study of rice production

“…Hence, nutrient reduction strategies and associated science assessment should be reviewed to help better guide implementation and tracking of water quality improvement practices [38][39][40]. In addition, nutrient management strategies for agricultural non-point source pollution control in irrigation area should be improved in order to protect water resources and to control environmental pollution in catchment area [41][42][43]. In this context, it is important to create and propose a good management plan in order to properly manage and distribute water supply to all sectors.…”