2026-10-07T04:59:34Z https://api.figshare.com/v2/oai

oai:figshare.com:article/34002330 2026-09-26T06:23:37Z category_26983 category_26986 item_type_3 month_year_09_2026

<b>Variation in Soil Microbial Nutrient Limitation and Carbon Use Efficiency and Their Driving Mechanisms in Riparian Wetlands</b> peixuan yan (23862285) Soil biology Soil chemistry and soil carbon sequestration (excl. carbon sequestration science) MICROBIAL BIOMASS-C wetland change extracellular enzyme responsible <p dir="ltr">Riparian wetlands are subject to periodic hydrological disturbances that cause pronounced fluctuations in soil resource availability and redox conditions, which, in turn, influence microbial resource acquisition and carbon allocation. However, patterns of microbial resource limitation and carbon use efficiency (CUE), together with their underlying driving mechanisms, remain unclear. In this study, we investigated riparian wetlands in the Three Gorges Reservoir Region and classified sampling plots according to C–S–R ecological strategies. We measured soil physicochemical properties, microbial biomass, and extracellular enzyme activities, assessed microbial resource limitation using ecoenzymatic stoichiometry and vector analysis, and employed random forest analysis and piecewise structural equation modelling (piecewiseSEM) to identify the key drivers and pathways influencing CUE. The results showed that microbial biomass and the activities of carbon‑ and phosphorus‑acquisition enzymes differed significantly among plant communities, whereas microbial biomass stoichiometric ratios and nitrogen-acquisition enzyme activities remained relatively stable. Ecoenzymatic vector angles in the riparian wetlands were consistently greater than 45°, indicating that soil microorganisms generally experienced strong potential P limitation, whereas vector length and CUE varied significantly among plant communities. Random forest and piecewiseSEM analyses showed that vector length, the microbial biomass carbon‑to‑nitrogen ratio, the soil organic carbon‑to‑total nitrogen ratio, dissolved organic carbon, bulk density, and vector angle were key predictors of CUE. CUE was jointly regulated by soil nutrients, microbial biomass, and extracellular enzyme activity patterns. Extracellular enzymes exerted a strong direct effect on CUE, whereas soil nutrients exerted a strong indirect effect through microbial biomass and extracellular enzymatic processes. This study advances our understanding of the mechanisms regulating microbial metabolism in riparian wetlands under hydrological fluctuations and provides an important theoretical basis for accurately evaluating the soil carbon sequestration potential of wetlands.</p> 2026-09-26T06:23:37Z Dataset Dataset 10.6084/m9.figshare.34002330.v1 https://figshare.com/articles/dataset/_b_Variation_in_Soil_Microbial_Nutrient_Limitation_and_Carbon_Use_Efficiency_and_Their_Driving_Mechanisms_in_Riparian_Wetlands_b_/34002330 CC BY 4.0