Abstract
The research on the effect of water-saving irrigation technology on the loss of nutrients and chemical substances in farmland has become a hot issue in the field of agricultural water and soil. Based on comparative experiments and combined with the isotope N15 tracer technique, the mechanism of nitrogen migration and transformation and the trend of fertilizer nitrogen use under different irrigation modes were studied. The results showed that water-saving irrigation modes (thin and wet irrigation W1 and intermittent irrigation W2) could reduce the NO3−-N leaching loss by reducing the water leakage amount and the NO3−-N concentration, and effectively inhibit the leaching loss of fertilizer nitrogen. Compared with conventional irrigation (W0), the leaching loss amount of fertilizer nitrogen in W1 and W2 decreased by 62% and 64%, respectively. Under the same amount of fertilizer, water-saving irrigation mode can significantly reduce the total amount of ammonia (NH3) volatilization and the proportion of NH3 volatilization of fertilizer nitrogen in total NH3 volatilization, and significantly increase the nitrogen uptake of rice plants. Meanwhile, water-saving irrigation mode can increase the total nitrogen content of paddy soil by 14.0% but reduce the residual rate of fertilizer nitrogen in soil by 14.6%. Moreover, crop nitrogen uptake can be significantly increased under water-saving irrigation. Compared with W0, the nitrogen fertilizer use rate of W1 and W2 increased by 5.0% and 9.7%, respectively. The research results can provide an important basis for controlling agricultural non-point source pollution, curbing the decline of soil fertility and deterioration of soil quality in paddy fields.
Highlights
China is the world’s largest rice producer, with total rice production ranking first in the world [1].The rice area and production in Zhejiang Province accounts for 30% and 40% of the total grain production in China
The research results at home and abroad show that some high-efficiency water-saving irrigation techniques causing drought in paddy fields may lead to the decline in soil fertility after several years, and the fertility characteristics of paddy soils were attenuated or even lost, which was not conducive to sustaining high yield [3,4,5]
The results showed that the joint regulation of water-saving irrigation-controlled drainage had a positive effect on water, fertilizer, gas, and heat in the paddy field, but the fertilizer factor was not considered in the study
Summary
China is the world’s largest rice producer, with total rice production ranking first in the world [1]. The rice area and production in Zhejiang Province accounts for 30% and 40% of the total grain production in China. Water conservation and high yield of rice has important practical significance [2]. The research results at home and abroad show that some high-efficiency water-saving irrigation techniques causing drought in paddy fields may lead to the decline in soil fertility after several years, and the fertility characteristics of paddy soils were attenuated or even lost, which was not conducive to sustaining high yield [3,4,5]. Appropriate irrigation can promote the conversion and absorption of fertilizer nutrients and improve the use rate of fertilizers
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
