State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-environmental Science, Chinese Academy of Sciences, Beijing, 100085, China.
University of Chinese Academy of Sciences, Beijing, 100049, China.
Sci China Life Sci. 2018 Mar;61(3):340-347. doi: 10.1007/s11427-017-9144-9. Epub 2017 Oct 27.
The patchy distribution of vegetation in dry land results in well-documented "fertile islands". However, the response of shrub fertile islands to plant recovery and the underlying mechanisms, such as the linkage plant and soil properties, remain unknown. We sampled soils from areas with three different plant coverages (25%, 45%, and 75%) and three of their adjacent inter-plants to investigate soil physicochemical and microbial properties in the upper Minjiang River arid valley. The results showed that these factors were influenced by the persistence of plants that contrasted with the inter-plant interspaces. We found fertile islands in under-plant soil that were enhanced with increasing plant coverage, from 25% to 45% and 75%; however, there were no significant differences between 45% and 75% plant coverage apart from the soil clay content and the fungi to bacteria ratio. The soil microbial communities in under-plant soil were strongly influenced by the total soil carbon (TC), soil organic carbon (SOC), and available nitrogen (AN), whereas the microbial communities in inter-plant soil were primarily constrained by the AN and available phosphorous (AP). Moreover, the inter-plant soil properties, including gravimetric soil water content, pH, electrical conductivity (EC), and soil C:N ratio, were also strongly influenced by adjacent vegetation, which suggested that fertile islands may be beneficial for plant recovery in this region.
旱地植被的斑块分布导致了有充分记录的“肥沃岛屿”。然而，灌木肥沃岛屿对植物恢复的响应及其潜在机制，如植物和土壤特性的联系，仍然未知。我们从三个不同植物覆盖度（25%、45%和 75%）的区域和三个相邻的间隙中采集土壤样本，以调查岷江干旱河谷上游土壤的理化和微生物特性。结果表明，这些因素受到与间隙内植物对比的持久性的影响。我们发现，在植物覆盖度从 25%增加到 45%和 75%的情况下，下植物土壤中的肥沃岛屿得到了增强；然而，除了土壤粘粒含量和真菌与细菌比例外，45%和 75%植物覆盖度之间没有显著差异。下植物土壤中的土壤微生物群落受土壤总碳（TC）、土壤有机碳（SOC）和有效氮（AN）的强烈影响，而间隙土壤中的微生物群落主要受 AN 和有效磷（AP）的限制。此外，间隙土壤的特性，包括土壤重量含水量、pH 值、电导率（EC）和土壤 C：N 比，也受到相邻植被的强烈影响，这表明肥沃岛屿可能有利于该地区的植物恢复。
