Patterns and drivers of global gross nitrogen mineralization in soils
Patterns and drivers of global gross nitrogen mineralization in soils
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DOI：
10.1111/gcb.15851
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发表时间：
2021-08-29
影响因子：
11.6
通讯作者：
Chang, Scott X.
中科院分区：
文献类型：
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作者：
Elrys, Ahmed S.;Ali, Ahmad;Chang, Scott X.
土壤总氮矿化（GNM）是全球氮循环中的一个关键微生物过程，主要受气候和土壤性质的控制。本研究首次全面分析了土壤理化性质、气候及其与土壤微生物生物量（MB）的相互作用在全球GNM控制中的作用。通过对不同生态系统337篇已发表论文970项观测数据的meta分析，发现GNM与MB、全碳、全氮和降水呈显著正相关，与容重（BD）和土壤ph呈显著负相关。多元分析和结构方程模型表明，GNM受MB驱动，BD和降水对GNM的影响最大。总氮的增加通过增加总氮和总氮来促进GNM的增长，而降水量的增加则通过增加总氮来促进GNM的增长，而且GNM随生态系统类型的不同而变化，在总碳和总氮含量高、BD和pH值低的森林和草地中GNM比农田大。GNM在降雨量大的热带湿润土壤中最高，这增加了土壤基质（全氮）对微生物的供应。我们的研究结果表明，影响土壤微生物种群大小、BD、土壤基质有效性或土壤pH值的人为活动可能与降水制度和土地利用的变化相互作用，从而影响GNM，这可能最终影响生态系统生产力和环境氮损失。
Soil gross nitrogen (N) mineralization (GNM), a key microbial process in the global N cycle, is mainly controlled by climate and soil properties. This study provides for the first time a comprehensive analysis of the role of soil physicochemical properties and climate and their interactions with soil microbial biomass (MB) in controlling GNM globally. Through a meta-analysis of 970 observations from 337 published papers from various ecosystems, we found that GNM was positively correlated with MB, total carbon, total N and precipitation, and negatively correlated with bulk density (BD) and soil pH. Our multivariate analysis and structural equation modeling revealed that GNM is driven by MB and dominantly influenced by BD and precipitation. The higher total N accelerates GNM via increasing MB. The decrease in BD stimulates GNM via increasing total N and MB, whereas higher precipitation stimulates GNM via increasing total N. Moreover, the GNM varies with ecosystem type, being greater in forests and grasslands with high total carbon and MB contents and low BD and pH compared to croplands. The highest GNM was observed in tropical wet soils that receive high precipitation, which increases the supply of soil substrate (total N) to microbes. Our findings suggest that anthropogenic activities that affect soil microbial population size, BD, soil substrate availability, or soil pH may interact with changes in precipitation regime and land use to influence GNM, which may ultimately affect ecosystem productivity and N loss to the environment.