Soil quality and ecological benefits assessment of alpine desertified grassland following different ecological restoration measures

Yiran Li; Sijia Hu; Shanxin Lang; Yulin Pu; Shirong Zhang; Ting Li; Xiaoxun Xu; Yongxia Jia; Guiyin Wang; Dagang Yuan; Yun Li

doi:10.3389/fpls.2023.1283457

Soil quality and ecological benefits assessment of alpine desertified grassland following different ecological restoration measures

Front Plant Sci. 2023 Oct 25:14:1283457. doi: 10.3389/fpls.2023.1283457. eCollection 2023.

Authors

Yiran Li¹, Sijia Hu¹, Shanxin Lang¹, Yulin Pu¹, Shirong Zhang², Ting Li¹, Xiaoxun Xu², Yongxia Jia¹, Guiyin Wang², Dagang Yuan¹, Yun Li¹

Affiliations

¹ College of Resource Science, Sichuan Agricultural University, Chengdu, China.
² College of Environmental Science, Sichuan Agricultural University, Chengdu, China.

Abstract

Introduction: Soil quality plays an irreplaceable role in plant growth for restored grassland. However, few studies investigate the comprehensive effects considering soil and vegetation properties during the restoration of desertified grassland, which restrict the virtuous circle of restored grassland ecosystem.

Methods: By setting three restoration patterns of enclosure plus grass (EG), enclosure intercropping shrub-grass (ESG), and enclosure plus sand-barrier and shrub-grass (ESSG) with three different restoration years (≤5, 7-9, and ≥15 years), we selected 28 physicochemical and microbial indicators, and constructed a minimum data set (MDS) to analyze the influences of restoration measurements on soil quality and ecological benefits in alpine desertified grassland.

Results: The results showed that the MDS comprised seven soil quality indicators: silt, total nitrogen (TN), carbon-nitrogen ratio (C/N), total potassium (TK), microbial biomass carbon (MBC), microbial biomass phosphorus (MBP), and fungi. Soil quality index (SQI) and ecological restoration effect index (EREI) in restored grasslands significantly increased by 144.83-561.24% and 87.21-422.12%, respectively, compared with unrestored grassland, and their positive effects increased with extending restoration years. The increasing effects of SQI and EREI were the highest in ESSG, followed by EG and ESG. The increasing rate of SQI began to decrease after 5 years in EG and ESG, while it decreased after 7-9 years in ESSG, and that of EREI in EG was lower than ESSG in each restoration year. Our work revealed that ESSG was the optimum restoration pattern for desertified grassland, and anthropogenic monitoring and management measurements such as applying organic fertilization and mowing return reasonably should be carried out at the beginning of 5 years in EG and ESG as well as 7 years in ESSG to maintain sustainable ecological benefits.

Discussion: The study highlights that soil quality, including microbial properties, is a key factor to evaluate the restoration effects of desertified grassland.

Keywords: Zoige Plateau; ecological restoration effect index; grassland restoration; minimum data set; soil quality index.

Grants and funding

The author(s) declare financial support was received for the research, authorship, and/or publication of this article. This research was financially supported by a grant from Applied Basic Research Programs of Science and Technology Department of Sichuan Province, China (grant number 2021YJ0341) and Science and Technology Fundamental Resources Investigation Program, China (grant number 2022FY100200).