College of Life and Environmental Sciences, Minzu University of China, Beijing, 100081, China.
Northwest Institute of Plateau Biology, Chinese Academy of Sciences, Xining, 810008, Qinghai, China.
Microb Ecol. 2023 Nov;86(4):2870-2881. doi: 10.1007/s00248-023-02287-7. Epub 2023 Aug 24.
In the fragile Sanjiangyuan (SJY) agro-pasture ecotone of the Qinghai-Tibetan Plateau (QTP), planting and fencing have been used to alleviate grassland degradation and to provide high-quality grass seeds for the implementation of the project of "grain for green". The soil microbe is the major driving factor in maintaining plant productivity and soil nutrient cycling. However, few studies have explored the effects of planting and fencing on soil microorganisms in the SJY agro-pasture ecotone. We explored the effects of tilling (TG) and fencing after tilling (FTG) on soil microbial communities to reveal the effects of restoration measures on soil microbes and to provide a reference in assessing and improving ecosystem structure. The results showed that restoration measures increased soil microbial species diversity and significantly changed their community structure. We found, the microbial composition was more complex under FTG, and its fungal variability was higher and more similar to that of natural grassland. Additionally, restoration measures resulted in fungal co-occurrence network was more edges, higher density, larger diameter and more positive interactions. This was due to the management of the vegetation-soil microenvironment by FTG inducing a differentiation of microbial community structure. In summary, the implementation of FTG could change the microenvironment in the SJY agro-pasture ecotone, so that variation in the structure of microbial community tended toward that of natural grassland, and increased the stability of microbial co-occurrence network, which was more obvious in the fungal community. HIGHLIGHTS: • Restoration measures have changed the vegetation characteristics and soil microenvironment. • Fencing after tilling (FTG) has brought the microenvironment closer to natural grassland. • FTG significantly increased microbial unique ASVs. The number of fungal unique ASVs was similar to that of natural grassland. • FTG resulted in changes in microbial community structure towards natural grasslands and increased the stability of the microbial co-occurrence network, which was more apparent in the fungal community.
在青藏高原（QTP）脆弱的三江源（SJY）农牧交错带，种植和围栏已被用于缓解草原退化，并为实施“退耕还林还草”工程提供高质量的草种。土壤微生物是维持植物生产力和土壤养分循环的主要驱动因素。然而，很少有研究探讨种植和围栏对 SJY 农牧交错带土壤微生物的影响。我们探讨了翻耕（TG）和翻耕后围栏（FTG）对土壤微生物群落的影响，以揭示恢复措施对土壤微生物的影响，并为评估和改善生态系统结构提供参考。结果表明，恢复措施增加了土壤微生物物种多样性，并显著改变了其群落结构。我们发现，FTG 下微生物组成更为复杂，其真菌变异性更高，与天然草地更为相似。此外，恢复措施导致的真菌共生网络具有更多的边缘、更高的密度、更大的直径和更多的正相互作用。这是由于 FTG 对植被-土壤微环境的管理导致微生物群落结构的分化。总之，FTG 的实施可以改变 SJY 农牧交错带的微环境，使微生物群落结构的变化趋向于天然草地，并增加微生物共生网络的稳定性，真菌群落更为明显。
要点：
恢复措施改变了植被特征和土壤微环境。
翻耕后围栏（FTG）使微环境更接近天然草地。
FTG 显著增加了微生物特有 ASVs。真菌特有 ASVs 的数量与天然草地相似。
FTG 导致微生物群落结构向天然草地转变，并增加了微生物共生网络的稳定性，真菌群落更为明显。
