Water-Saving Potential of Different Agricultural Management Practices in an Arid River Basin

Abstract

Water scarcity threatens food security in arid areas, highlighting the importance of water-saving agriculture for food production. Agricultural management practices are developed to improve water-use efficiency, and their water-saving effects are generally evaluated at the field scale rather than the regional scale. To figure out the regional water-saving potential of irrigation methods and mulching practices, the FAO AquaCrop model was first calibrated and validated at the three experimental stations. With aggregating spatial information, a distributed model was constructed and validated in a typical arid river basin of northwest China. Twelve combinations of soil mulching (plastic and straw) and irrigation methods (basin, furrow, drip, and subsurface drip) were simulated using the model to evaluate the effect of agricultural management practices on crop evapotranspiration (ET), crop water productivity, and regional water consumption. The results showed that soil mulching, advanced irrigation methods, and their combinations reduced noneffective soil evaporation (E) and the E/ET ratios and improved crop water productivity. Plastic mulching combined with subsurface drip irrigation is the most promising practice, increasing the crop water productivity of seed maize and spring wheat by 18.2% and 11.1% on average and reducing regional crop water consumption by 7.7% (75.0 million m3) and 7.4% (72.7 million m3), respectively. The reduction in irrigation water extraction ranged from 20.6% under furrow irrigation with straw mulching to 68.7% under subsurface drip irrigation with plastic mulching. This study quantitatively assessed the water-saving potential of soil mulching, irrigation methods, and their combinations to reduce agricultural water use, offering practical implications for the management and development of water-saving agriculture in arid areas.

Global food trade alleviates transgressions of planetary boundaries at the national scale

“… 29 Plastic mulching combined with subsurface drip irrigation is shown to offer potentials to reduce water consumption by about 7 percent in arid regions. 30 In order to meet increasing food demands with limited land resources, conservation agriculture is a widely promoted concept that aims to prevent arable land losses while regenerating degraded lands. It promotes maintenance of a permanent soil cover, minimum soil disturbance, and diversification of plant species, which also contributes to increased water and nutrient use efficiency as well as productivity improvement.…”

“…Similar with Hu et al. (2020), 30 we downscale the global planetary boundaries for food systems assessed by Springmann et al. (2018) 11 to the country level using a multi-scale approach by incorporating the regional resource endowments.…”

“…It should be noted that while some previous studies, such as Hu et al. (2020), 30 determined the national boundaries for nitrogen and phosphorous using the discharge amounts of nitrogen and phosphorous to water bodies, we used the application amounts of nitrogen and phosphorous, same as Springmann et al. (2018), 11 due to the methodological difficulties and uncertainties in determining the leaching ratios of nitrogen and phosphorous throughout the globe.…”

Water Management for Sustainable Irrigation in Rice (Oryza sativa L.) Production: A Review

“…Various previous studies focused on good agronomic practices (GAP), such as using drought-tolerant rice variety [47,143], plastic mulching [34], straw mulching [144], organic matter application [17,145], minimum tillage [121], etc., to assess their influence on water saving in irrigated rice production. In addition, water-saving practices are implemented in combination with these good agronomic practices (GAP).…”

“…Numerous studies have been carried out to reduce the environmental impact of rice cultivation and to promote smart and sustainable rice production, such as reducing greenhouse gas emissions, optimizing the water and fertilizers used for rice cultivation, and improving paddy yields and quality of milled rice [15][16][17][18][19][20][21][22][23][24]. Thus, several water and soil conservation practices for rice cultivation were developed and implemented on rice farming to improve water and soil management as well as develop efficient irrigation systems [25][26][27][28][29][30][31][32][33][34]. The effectiveness of these technologies is assessed using water management indicators, such as water use efficiency/water productivity.…”