Work

Utilization of soil and fertilizer nitrogen supply under mulched drip irrigation with various water qualities in arid regions

Year: 2023

Type: article

Abstract: Upgrading the efficiency of native soil nitrogen (N) and balancing the N derived from soil and fertilizers under drip irrigation with low-quality water is crucial for reducing N application and curtailing environmental degradation in arid regions. In this study, a control experiment with four N (15N-labeled urea) rates of 0 (F0), 255 (F1), 315 (F2) and 375 kg·ha−1 (F3) was established by applying groundwater (Q1, 1.27 g·l−1), brackish water (Q2, 3.03 g·l−1) and saline water (Q3, 4.90 g·l−1) to differentiate cotton (Gossypium hirsutum L.) uptake from native soil N and fertilizer N by 15N tracer technology. The results indicated that increasing water salinity increased the soil salt content and significantly reduced cotton biomass. The cumulative utilization percentages of soil N (CUSN) and fertilizer N (CUFN) ranged from 7.4% to 14.1% and 35.9–54.5%, respectively, during the growing season. The CUFN decreased with increasing irrigation water salinity. Appropriate nitrogen fertilizer alleviated the salt stress on N uptake. The N rate of 315 kg·ha−1 promoted soil N and fertilizer N uptake and produced higher percentages of utilization of soil N (PUSN) and fertilizer N (PUFN) during the squaring and flower boll stage under Q1 and Q2 irrigation. An N rate of 375 kg·ha−1 significantly increased PUSN under Q3 irrigation, particularly during the mature stage. In addition, high salinity water and N rates caused a larger fertilizer N loss. Considering cotton growth and balance between soil N and fertilizer N, an N rate of 315 kg·ha−1 was suitable for cotton under mulched drip irrigation when applying Q1 and Q2 in arid regions, and 375 kg·ha−1 was recommended for Q3 irrigation. The appropriate addition of nitrogen fertilizer during the flower boll stage will promote cotton growth under brackish water.

Source: Agricultural Water Management

DOI: 10.1016/j.agwat.2023.108219

Authors: Chao Ma, Jun Wang, Jiusheng Li

Institutions: China Institute of Water Resources and Hydropower Research, State Key Laboratory of Basin Water Cycle Simulation and Regulation

Language: English

Topic: Irrigation Practices and Water Management

Subfield: Soil Science

Field: Agricultural and Biological Sciences

Domain: Life Sciences

SDGs: Zero hunger, Clean water and sanitation

Open Access status: gold

Estimated APC paid: $2,600