Intensity and frequency of nitrogen addition alter soil chemical properties depending on mowing management in a temperate steppe

Ruzhen Wang; Yunhai Zhang; Peng He; Jinfei Yin; Junjie Yang; Heyong Liu; Jiangping Cai; Zhan Shi; Xue Feng; Feike A Dijkstra; Xingguo Han; Yong Jiang

doi:10.1016/j.jenvman.2018.07.036

Intensity and frequency of nitrogen addition alter soil chemical properties depending on mowing management in a temperate steppe

J Environ Manage. 2018 Oct 15:224:77-86. doi: 10.1016/j.jenvman.2018.07.036. Epub 2018 Jul 20.

Authors

Ruzhen Wang¹, Yunhai Zhang², Peng He¹, Jinfei Yin¹, Junjie Yang², Heyong Liu¹, Jiangping Cai², Zhan Shi¹, Xue Feng¹, Feike A Dijkstra³, Xingguo Han², Yong Jiang⁴

Affiliations

¹ State Engineering Laboratory of Soil Nutrient and Management, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, China.
² State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China.
³ Sydney Institute of Agriculture, School of Life and Environmental Sciences, The University of Sydney, Sydney, NSW 2006, Australia.
⁴ State Engineering Laboratory of Soil Nutrient and Management, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, China. Electronic address: jiangyong@iae.ac.cn.

PMID: 30031921
DOI: 10.1016/j.jenvman.2018.07.036

Abstract

Anthropogenic nitrogen (N) enrichment can significantly alter soil chemical properties in various ecosystems. Previous manipulative N experiments mainly focused on the intensity of N addition on soil properties by changing N input rates. It remains unclear, however, whether frequency of N addition can affect soil chemical properties. We examined the effects of frequency (2 versus 12 applications yr^-1) and rate (ranging from 0 to 50 g N m^-2 yr^-1) of N addition on soil chemical properties of pH, base cations, soil pH buffering capacity (pHBC), and soil available micronutrients in a temperate steppe with and without mowing. Mowing significantly increased the effective cation exchange capacity (ECEC), soil exchangeable Ca and Na, available Fe, and soil pHBC when N was applied at low frequency. Low frequency of N addition significantly decreased soil pH and exchangeable Na but increased soil exchangeable Mg without mowing; however, it increased soil exchangeable Na and available Zn with mowing, while available Fe and Mn increased both with and without mowing. Higher rates of N addition (≥20 g N m^-2 yr^-1) decreased soil pH, ECEC and exchangeable Ca but increased soil available Fe, Mn and Cu regardless of the mowing treatment and frequency of N addition. Changes in soil organic matter, pHBC and ECEC were the main reasons affecting soil pH across mowing and N application treatments. Our results indicate that frequency of N addition played an essential role in altering soil chemical properties. Simulating N deposition via large and infrequent N additions can underestimate (exchangeable Mg and available Fe and Mn) or overestimate (soil pH and exchangeable Na) changes in soil properties. Our results further suggest that the effects of frequency of N addition on soil chemical attributes in semi-arid grassland ecosystems can be regulated by appropriate mowing management.

Keywords: Base cation; Nitrogen deposition; Semi-arid grassland; Soil acid buffering capacity; Soil acidification; Soil micronutrient.

MeSH terms

Ecosystem
Nitrogen*
Soil / chemistry*
Soil Microbiology*

Substances

Soil
Nitrogen