Influence of drip irrigation by reclaimed water on the dynamic change of the nitrogen element in soil and tomato yield and quality

Abstract

This paper carries out an analysis of the influence of the dynamic change pattern of soil in every crop growth period and irrigation by reclaimed water on yield and quality of fruit and vegetables comparative to drip irrigation by groundwater under the condition of drip irrigation by reclaimed water based on a field experiment. The results show the variation of peak value of concentration of NH4+—N in topsoil is: drip irrigation by reclaimed water > drip irrigation by 50% reclaimed water > drip irrigation by groundwater, the concentration of NH4+-N is higher at the depth of 0–40 cm with almost no accumulation of NH4+-N below the depth of 40 cm NO3-N presence in soil slightly increases across the entire growth period with irrigation by reclaimed water. Irrigation by reclaimed water increases tomato yield and irrigation water use efficiency, and has an improved taste index indicated by an improved soluble sugar and titratable acidity content of the fruit without any obvious adverse influence on the nutritive indexes such as Vc soluble solid. The shortening of the irrigation period and increase in buried depth of drip irrigation tape are to promote an increase in tomato yield and irrigation water use efficiency to carry out drip irrigation by reclaimed water under the condition of having a shorter irrigation period and a greater depth of drip irrigation tape and to yield a higher rate of water conservation.