Open Access

ARTICLE

Contributions of Volume and Concentration on Runoff Nitrogen Losses from Intensive Vegetable in China

by Mingkun Cheng^1,2, Ju Min^2,*, Yanying Zhang², Yuhe Wang³, Xia Wang⁴, Weiming Shi^1,*

1 Department of Horticulture, Foshan University, Foshan, 528000, China
2 State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences (CAS), Nanjing, 210008, China
3 College of Life Sciences, Anhui Normal University, Wuhu, 241000, China
4 Quality Department, Jiangsu Environmental Monitoring Center, Nanjing, 210036, China

* Corresponding Authors: Ju Min. Email: ; Weiming Shi. Email:

Phyton-International Journal of Experimental Botany 2024, 93(9), 2439-2453. https://doi.org/10.32604/phyton.2024.054182

Received 21 May 2024; Accepted 29 August 2024; Issue published 30 September 2024

Abstract

Vegetable runoff nitrogen (N) loss is a serious environmental issue. However, whether the volume or N content of runoff determines the final N losses has not been clarified, which limited the optimal N managements in vegetable production. Here, we conducted a simulated rainfall experiment to study the runoff N loss flux pattern and the accumulation rate as well as the main influencing factors. The results showed that at 20 to 30 min, the volume of runoff water with a high N content reaches a critical inflection point of increase. Under 55 mm/h rainfall intensity, the N concentration decreased continuously. Under 75 mm/h, the soluble N concentration decreased during the first 25 min; thereafter, it stabilized. However, the total and particulate N decreased significantly after 30 min. Nitrogen losses via runoff from vegetable fields were from 18.5 to 26.0 kg/ha under two rainfall intensities. Runoff soluble N losses were mainly attributed to applied fertilizers (79.7%–95.5%), while particulate N losses were primarily originated from soil-retained N. Our data indicates that there was a significant difference in N losses pattern and influencing factors under varied fertilizer N inputs and rainfall intensities, which can help to optimize water and N fertilizer managements to mitigate non-point source N pollutants. In the future, long-term multi-site and -crop studies should be conducted to comprehensively clarify the N runoff losses in vegetable soils.

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Keywords

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