Irrigation has more influence than fertilization on leaching water quality and the potential environmental risk in excessively fertilized vegetable soils

Abstract

Excessive fertilization is a common agricultural practice that often negatively influence soil and environmental quality in intensive vegetable production systems in China. To reduce negative effects of excessive fertilization, current studies generally focused on fertilizer management but not irrigation. In this study, we investigated the effects of fertilization and irrigation on soil properties, leaching water characteristics, plant growth, cucumber yield, irrigation water use efficiency (IWUE) and partial factor productivity of nitrogen (PFPN) in a double cropping system. The treatments included (i) conventional irrigation with conventional N fertilization (IcNc), (ii) optimal irrigation with conventional N fertilization (IoNc), (iii) conventional irrigation with optimal N fertilization (IcNo), and (iv) optimal irrigation with optimal N fertilization (IoNo). In general, fertilization merely influenced concentrations of nitrate (NO3-), phosphorus (P) and potassium (K), but did not affect most leaching water characteristics. In contrast, irrigation influenced pH, EC and concentrations of P, K, Ca, Mg, Na and Cu. Cumulative leached amounts of NO3-, P, K, Ca, Mg, Na, Fe, Cu and Zn were significantly decreased by optimal irrigation as compared to conventional irrigation under same fertilization conditions, but not by optimal fertilization as compared to conventional fertilization under same irrigation conditions. The leachate volume was strongly positively correlated with cumulative leached amounts of all tested elements, and these relationships were obviously influenced by irrigation but not fertilization. The IoNo treatment significantly increased both IWUE and PFPN as compared to the IcNc treatment. However, the IcNo treatment only enhanced PFPN, while the IoNc treatment improved IWUE, when compared to the IcNc treatment. Our results suggested that irrigation has more influence than fertilization on leaching water quality and that the optimal irrigation combined with optimal fertilization was efficient in reducing the potential environmental risk caused by excessive fertilization in intensive vegetable production systems.

Ecological and Economic Sustainability in Olive Groves with Different Irrigation Management and Levels of Erosion: A Case Study

“…In Estepa, nitrate content, an indicator of N fertilisation, increased directly with erosion levels and its concentration was higher in irrigated olive groves. Numerous studies have shown that irrigation and fertilisation influence nitrate leaching in agricultural ecosystems [81]. According to the results of our study, in agreement with [81], the use of fertilisers should be managed not only considering the amount of fertiliser that is applied but also the irrigation management measures (amount of water, irrigation time and irrigation method).…”

“…Numerous studies have shown that irrigation and fertilisation influence nitrate leaching in agricultural ecosystems [81]. According to the results of our study, in agreement with [81], the use of fertilisers should be managed not only considering the amount of fertiliser that is applied but also the irrigation management measures (amount of water, irrigation time and irrigation method). Therefore, irrigation could be as important as fertilisation in leaching water quality, and optimal irrigation combined with optimal fertilisation could reduce the potential environmental risk caused by excessive fertilisation in intensive systems of olive groves.…”

The interactive responses of fertigation levels under buried straw layer on growth, physiological traits and fruit yield in tomato plant

“…A higher application of nitrogen fertilizer may cause leaching of NO 3 -N correspondingly (Ullah et al 2017) and ultimately disturb the nitrate contents in fruits of tomato (Wang et al 2015). At the same time, higher application of water will inevitably promote leaching and waste of fertilizer (Ullah et al 2017;Li et al 2018). To fulfill the high demand of food, there is conflict to recommendations to lessen the use of fertilizer in China as it is considered as a risk of production decrease, despite the extensive evidence.…”

Rootstock x Environment Interactions on Nitrogen-Use Efficiency in Grafted Tomato Plants at Different Phenological Stages

“…Then, it is necessary to adapt production techniques that minimize the negative impacts on the environment. Several strategies have been proposed to reduce N pollution from intensive agricultural systems, including partial or complete replacement of conventional fertilizers by organic sources [4], recirculating drainage water in closed-loop systems [5], tightly adjusting irrigation and fertilizer inputs to crop's needs [6,7], and selecting highly efficient varieties for N uptake [8], among others. More recently, grafting has been suggested as a practice that improves crop's nitrogen-use efficiency (NUE) due to a combination of traits, including vigorous root systems, high water and nutrient uptake capacity, and high photosynthetic efficiency [9][10][11].…”