Nutrient supply drives concurrent K-to-r strategist shifts and competitive intensification in biocrust bacterial communities

Lina Zhao; Wenjing Zhang; Ning Chen; Bettina Weber; Tianjiao Dai; Rongliang Jia; Shaobin Gu; Xinrong Li

doi:10.59717/j.xinn-life.2026.100195

The Innovation Life > 2026 Vol. 4 > No. 1 > 100195

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Nutrient supply drives concurrent K-to-r strategist shifts and competitive intensification in biocrust bacterial communities

1.
College of Food and Bioengineering, Henan University of Science and Technology, Luoyang 471000, China
2.
State Key Laboratory of Soil Water Conservation and Desertification Control, Northwest Agriculture and Forestry University, Yangling 712100, China
3.
State Key Laboratory of Herbage Improvement and Grassland Agro-Ecosystems, College of Ecology, Lanzhou University, Lanzhou 730000, China
4.
Institute for Biology, University of Graz, Holteigasse 6, 8010 Graz, Austria
5.
School of Water Resources and Environment, China University of Geosciences (Beijing), Beijing 100083, China
6.
Shapotou Desert Research & Experiment Station, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China

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Corresponding authors: shaobingu@haust.edu.cn (S.G); lxinrong@lzb.ac.cn (X.L)
Received Date: August 06, 2025

Accepted Date: January 09, 2026

Published Online: January 16, 2026

The Innovation Life 4(1), https://doi.org/10.59717/j.xinn-life.2026.100195 | Cite this article

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GRAPHICAL ABSTRACT

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PUBLIC SUMMARY

PUBLIC SUMMARY
1. Increased nutrient supply favored fast-growing, resource-exploiting bacteria.
  
  Biocrust bacterial complexity and interactions increased with nutrient supply.
  
  Negative interactions among biocrust bacteria intensified with nutrient supply.
  
  Six keystone species with different responses to nutrient supply were identified.
  
  Targeted nutrient and keystone taxa management aids dryland restoration.

ABSTRACT

ABSTRACT

Biological soil crusts (biocrusts) cover ~30% of global drylands and regulate biogeochemical cycles through bacterial metabolic activities. Although nutrient scarcity profoundly influences biocrust bacterial communities, the general principles governing their nutrient response dynamics remain unclear. Here, we employed controlled microcosms to investigate how differential nutrient supply reshaped bacterial life-history traits and interspecies interactions in both cyanobacteria- and moss-dominated biocrusts. Our findings revealed that with increased nutrient supply, the ribosomal RNA gene operon (rrn) copy numbers in bacterial communities significantly increased, while the ratio of oligotrophs to copiotrophs decreased, indicating a shift from K-strategists to r-strategists. Network analysis showed that nutrient supply increased node number, link number, average degree, and negative correlations, indicating stronger interactions within the bacterial community. Keystone taxa analysis identified six keystone taxa, with Arthrobacter, Nocardioides, and Ellin6055 responding negatively, and Bacillus, Tumebacillus, and Fictibacillus responding positively to nutrient supply. Furthermore, bacterial community structure, including life-history strategies, network topology, and keystone taxa, was strongly correlated with soil properties, particularly the contents of available nitrogen and potassium and total phosphorus. Our study establishes a mechanistic framework for nutrient-driven bacterial assembly in dryland ecosystems, providing practical strategies for ecological stabilization through optimized nutrient management and targeted manipulation of bacterial keystone taxa.

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Zhao L., Zhang W., Chen N., et al. (2026). Nutrient supply drives concurrent K-to-r strategist shifts and competitive intensification in biocrust bacterial communities. The Innovation Life 4:100195. https://doi.org/10.59717/j.xinn-life.2026.100195

Zhao L., Zhang W., Chen N., et al. (2026). Nutrient supply drives concurrent K-to-r strategist shifts and competitive intensification in biocrust bacterial communities. The Innovation Life 4:100195. https://doi.org/10.59717/j.xinn-life.2026.100195

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Nutrient supply drives concurrent K-to-r strategist shifts and competitive intensification in biocrust bacterial communities

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