Xu Hongwei, Qu Qing, Wang Zhanhui, Xue Sha, Xu Zhenfeng
National Forestry and Grassland Administration Key Laboratory of Forest Resources Conservation and Ecological Safety on the Upper Reaches of the Yangtze River, Forestry Ecological Engineering in the Upper Reaches of the Yangtze River Key Laboratory of Sichuan Province, Sichuan Agricultural University, Chengdu, China.
State Key Laboratory of Soil Erosion and Dryland Farming on Loess Plateau, Institute of Soil and Water Conservation, Northwest A&F University, Yangling, China.
Front Plant Sci. 2022 Sep 20;13:1009886. doi: 10.3389/fpls.2022.1009886. eCollection 2022.
Studying plant-soil feedback (PSF) can improve the understanding of the plant community composition and structure; however, changes in plant-soil-enzyme stoichiometry in response to PSF are unclear. The present study aimed to analyze the changes in plant-soil-enzyme stoichiometry and microbial nutrient limitation to PSF, and identify the roles of nutrient limitation in PSF. , , and were selected as representative grass species in early-, mid-, and late-succession; furthermore, three soil types were collected from grass species communities in early-, mid-, and late-succession to treat the three successional species. A 3-year (represents three growth periods) PSF experiment was performed with the three grasses in the soil in the three succession stages. We analyzed plant biomass and plant-soil-enzyme C-N-P stoichiometry for each plant growth period. The plant growth period mainly affected the plant C:N in the early- and late- species but showed a less pronounced effect on the soil C:N. During the three growth periods, the plants changed from N-limited to P-limited; the three successional species soils were mainly limited by N, whereas the microbes were limited by both C and N. The plant-soil-enzyme stoichiometry and plant biomass were not significantly correlated. In conclusion, during PSF, the plant growth period significantly influences the plant-soil-microbial nutrient limitations. Plant-soil-enzyme stoichiometry and microbial nutrient limitation cannot effectively explain PSF during succession on the Loess Plateau.
研究植物-土壤反馈（PSF）有助于增进对植物群落组成和结构的理解；然而，植物-土壤-酶化学计量比在PSF作用下的变化尚不清楚。本研究旨在分析植物-土壤-酶化学计量比的变化以及微生物对PSF的养分限制，并确定养分限制在PSF中的作用。选取 、 和 作为演替早期、中期和后期的代表性草种；此外，从演替早期、中期和后期的草种群落中采集三种土壤类型，用于处理这三个演替阶段的物种。在三个演替阶段的土壤中，对这三种草进行了为期3年（代表三个生长周期）的PSF实验。我们分析了每个植物生长周期的植物生物量以及植物-土壤-酶的碳-氮-磷化学计量比。植物生长周期主要影响早期和晚期物种的植物碳氮比，但对土壤碳氮比的影响较小。在三个生长周期中，植物从氮限制转变为磷限制；三个演替阶段物种的土壤主要受氮限制，而微生物则受碳和氮的双重限制。植物-土壤-酶化学计量比与植物生物量之间没有显著相关性。总之，在PSF过程中，植物生长周期显著影响植物-土壤-微生物的养分限制。在黄土高原的演替过程中，植物-土壤-酶化学计量比和微生物养分限制无法有效解释PSF。
