Sun Yunlong, Zhang Shu, Liang Yueming, Yu Xuan, Pan Fujing
College of Environmental and Engineering, Guangxi Key Laboratory of Environmental Pollution Control Theory and Technology, Guilin University of Technology, Guilin 541006, China.
Engineering Research Center of Watershed Protection and Green Development for University in Guangxi, Guilin University of Technology, Guilin 541006, China.
Microorganisms. 2025 Mar 4;13(3):590. doi: 10.3390/microorganisms13030590.
Natural restoration has emerged as a prominent approach in recent decades for the rehabilitation of degraded ecosystems globally. However, the specific changes and underlying mechanisms by natural restoration that influence the multifunctionality of karst ecosystems remain poorly understood. In this study, soil, litter, and fine root samples were collected from four chronosequence stages of vegetation restoration-grassland (G), shrubland (SH), shrub-tree land (ST), and forest (F)-within a karst ecosystem in Southwestern China. The aim was to evaluate the impacts of vegetation restoration on ecosystem multifunctionality using an averaging approach. The results demonstrated that the indices of C-cycling functionality, N-cycling functionality, P-cycling functionality, and total ecosystem multifunctionality increased as vegetation restoration progressed, along with plant diversity. The structure of plant, bacterial, and fungal communities varied across different stages of vegetation restoration, exhibiting the highest microbial diversity indices in the SH stage. Additionally, the tightness and complexity of co-occurrence networks of bacteria and fungi increased with advancing vegetation restoration, and higher positive links were observed in fungi than bacteria. The four functional indices were significantly and positively correlated with increasing plant diversity, fine root and litter nutrient contents, fine root biomass, microbial biomass, fungal community, enzyme activities, and soil nutrient contents but not with bacterial and fungal diversities. Furthermore, Random Forest model results revealed that plants exerted a significantly greater influence on ecosystem multifunctionality compared to other factors. It is plausible that plants influence soil microbial biomass, fungal community and co-occurrence networks, enzyme activities, and nutrient levels through the input of root and litter nutrients rather than by altering microbial diversity to enhance karst ecosystem multifunctionality. Therefore, initiatives to increase plant diversity are beneficial for sustainable ecological restoration management in the karst regions of Southwestern China.
近几十年来，自然恢复已成为全球退化生态系统恢复的一种重要方法。然而，自然恢复影响喀斯特生态系统多功能性的具体变化和潜在机制仍知之甚少。在本研究中，从中国西南喀斯特生态系统内植被恢复的四个时间序列阶段——草地（G）、灌丛地（SH）、灌乔木地（ST）和森林（F）——采集了土壤、凋落物和细根样本。目的是使用平均法评估植被恢复对生态系统多功能性的影响。结果表明，随着植被恢复的进行，碳循环功能、氮循环功能、磷循环功能和总生态系统多功能性指数以及植物多样性均有所增加。植物、细菌和真菌群落结构在植被恢复的不同阶段有所不同，在灌丛地阶段表现出最高的微生物多样性指数。此外，细菌和真菌共现网络的紧密性和复杂性随着植被恢复进程而增加，且在真菌中观察到的正相关联系比细菌更多。这四个功能指数与植物多样性增加以及细根和凋落物养分含量、细根生物量、微生物生物量、真菌群落、酶活性和土壤养分含量显著正相关，但与细菌和真菌多样性无关。此外，随机森林模型结果显示，与其他因素相比，植物对生态系统多功能性的影响显著更大。植物可能通过根系和凋落物养分输入影响土壤微生物生物量、真菌群落和共现网络、酶活性以及养分水平，而不是通过改变微生物多样性来增强喀斯特生态系统多功能性。因此，增加植物多样性的举措有利于中国西南喀斯特地区的可持续生态恢复管理。
