Yang Zhi, Yuan Yong, Guo Jinjin, Li Jinxi, Li Jianhua, Yu Hu, Zeng Wen, Huang Yinhong, Yin Liyun, Li Fulian
Faculty of Modern Agricultural Engineering, Kunming University of Science and Technology, Kunming 650500, China.
Yunnan Provincial Field Scientific Observation and Research Station on Water-Soil-Crop System in Seasonal Arid Region, Kunming University of Science and Technology, Kunming 650500, China.
Plants (Basel). 2024 May 31;13(11):1525. doi: 10.3390/plants13111525.
Biological soil crusts (BSCs) are often referred to as the "living skin" of arid regions worldwide. Yet, the combined impact of BSCs on soil carbon (C), nitrogen (N), phosphorus (P), and enzyme activities remains not fully understood. This study identified, screened and reviewed 71 out of 2856 literature sources to assess the responses of soil C, N, P and enzyme activity to BSCs through a meta-analysis. The results indicated that BSC presence significantly increased soil C, N, P and soil enzyme activity, and this increasing effect was significantly influenced by the types of BSCs. Results from the overall effect showed that soil organic carbon (SOC), total nitrogen (TN), available nitrogen (AN), total phosphorus (TP), and available phosphorus (AP) increased by 107.88%, 84.52%, 45.43%, 27.46%, and 54.71%, respectively, and four soil enzyme activities (Alkaline Phosphatase, Cellulase, Sucrase, and Urease) increased by 93.65-229.27%. The highest increases in SOC, TN and AN content occurred in the soil covered with lichen crusts and moss crusts, and significant increases in Alkaline Phosphatase and Cellulase were observed in the soil covered with moss crusts and mixed crusts, suggesting that moss crusts can synergistically enhance soil C and N pool and enzyme activity. Additionally, variations in soil C, N, P content, and enzyme activity were observed under different environmental settings, with more pronounced improvements seen in coarse and medium-textured soils compared to fine-textured soils, particularly at a depth of 5 cm from the soil surface. BSCs in desert ecosystems showed more significant increases in SOC, TN, AN, and Alkaline Phosphatase compared to forest and grassland ecosystems. Specifically, BSCs at low altitude (≤500 m) with an annual average rainfall of 0-400 mm and an annual average temperature ≤ 10 °C were the most conducive to improving soil C, N, and P levels. Our results highlight the role of BSCs and their type in increasing soil C, N, P and enzyme activities, with these effects significantly impacted by soil texture, ecosystem type, and climatic conditions. The implications of these findings are crucial for soil enhancement, ecosystem revitalization, windbreak, and sand stabilization efforts in the drylands of China.
生物土壤结皮（BSCs）常被称为全球干旱地区的“活皮肤”。然而，生物土壤结皮对土壤碳（C）、氮（N）、磷（P）和酶活性的综合影响仍未完全明晰。本研究从2856篇文献来源中筛选并综述了71篇，通过荟萃分析评估土壤碳、氮、磷和酶活性对生物土壤结皮的响应。结果表明，生物土壤结皮的存在显著增加了土壤碳、氮、磷和土壤酶活性，且这种增加效应受生物土壤结皮类型的显著影响。总体效应结果显示，土壤有机碳（SOC）、全氮（TN）、有效氮（AN）、全磷（TP）和有效磷（AP）分别增加了107.88%、84.52%、45.43%、27.46%和54.71%，四种土壤酶活性（碱性磷酸酶、纤维素酶、蔗糖酶和脲酶）增加了93.65 - 229.27%。SOC、TN和AN含量的最高增幅出现在地衣结皮和苔藓结皮覆盖的土壤中，在苔藓结皮和混合结皮覆盖的土壤中观察到碱性磷酸酶和纤维素酶显著增加，这表明苔藓结皮能协同增强土壤碳和氮库以及酶活性。此外，在不同环境条件下观察到土壤碳、氮、磷含量和酶活性的变化，与质地细的土壤相比，质地粗和中等质地的土壤改善更为明显，尤其是在距土壤表面5厘米深处。与森林和草原生态系统相比，沙漠生态系统中的生物土壤结皮在SOC、TN、AN和碱性磷酸酶方面的增加更为显著。具体而言，年平均降雨量为0 - 400毫米、年平均温度≤10℃的低海拔（≤500米）生物土壤结皮最有利于提高土壤碳、氮和磷水平。我们的研究结果突出了生物土壤结皮及其类型在增加土壤碳、氮、磷和酶活性方面的作用，这些效应受土壤质地、生态系统类型和气候条件的显著影响。这些发现对于中国干旱地区的土壤改良、生态系统恢复、防风固沙努力具有至关重要的意义。
