Open Access

ARTICLE

Unexpected Diversity in Ecosystem Nutrient Responses to Experimental Drought in Temperate Grasslands

by Biying Qiu^1,2, Niwu Te², Lin Song², Yuan Shi², Chuan Qiu², Xiaoan Zuo³, Qiang Yu⁴, Jianqiang Qian⁵, Zhengwen Wang², Honghui Wu^6,7, Wentao Luo^2,*

1 School of Life Sciences, Hebei University, Baoding, 071002, China
2 Liaoning Northwest Grassland Ecosystem National Observation and Research Station, Erguna Forest-Steppe Ecotone Research Station, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, 110164, China
3 Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, 730030, China
4 School of Grassland Science, Beijing Forestry University, Beijing, 100083, China
5 College of Forestry, Henan Agricultural University, Zhengzhou, 450002, China
6 State Key Laboratory of Efficient Utilization of Arid and Semi-Arid Arable Land in Northern China, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
7 Key Laboratory of Arable Land Quality Monitoring and Evaluation, Ministry of Agriculture and Rural Affairs, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing, 100081, China

* Corresponding Author: Wentao Luo. Email:

(This article belongs to the Special Issue: Grassland Ecology in China under Global Change)

Phyton-International Journal of Experimental Botany 2024, 93(4), 831-841. https://doi.org/10.32604/phyton.2024.047560

Received 09 November 2023; Accepted 22 March 2024; Issue published 29 April 2024

Abstract

The responses of ecosystem nitrogen (N) and phosphorus (P) to drought are an important component of global change studies. However, previous studies were more often based on site-specific experiments, introducing a significant uncertainty to synthesis and site comparisons. We investigated the responses of vegetation and soil nutrients to drought using a network experiment of temperate grasslands in Northern China. Drought treatment (66% reduction in growing season precipitation) was imposed by erecting rainout shelters, respectively, at the driest, intermediate, and wettest sites. We found that vegetation nutrient concentrations increased but soil nutrient concentrations decreased along the aridity gradient. Differential responses were observed under experimental drought among the three grassland sites. Specifically, the experimental drought did not change vegetation and soil nutrient status at the driest site, while strongly reduced vegetation but increased soil nutrient concentrations at the site with intermediate precipitation. On the contrary, experimental drought increased vegetation N concentrations but did not change vegetation P and soil nutrient concentrations at the wettest site. In general, the differential effects of drought on ecosystem nutrients were observed between manipulative and observational experiments as well as between sites. Our research findings suggest that conducting large-scale, consistent, and controlled network experiments is essential to accurately evaluate the effects of global climate change on terrestrial ecosystem bio-geochemistry.

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Keywords

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