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Hui Wang Yi Ding Yuguang Zhang Jingxin Wang Zachary B. Freedman Pengcheng Liu Wei Cong Jian Wang Runguo Zang Shirong Liu 《Global Change Biology》2023,29(10):2852-2864
Higher tree species richness generally increases the storage of soil organic carbon (SOC). However, less attention is paid to the influence of varied tree species composition on SOC storage. Recently, the perspectives for the stronger persistence of SOC caused by the higher molecular diversity of organic compounds were proposed. Therefore, the influences of tree species richness and composition on the molecular diversity of SOC need to be explored. In this study, an index of the evenness of diverse SOC chemical components was proposed to represent the potential resistance of SOC to decomposition under disturbances. Six natural forest types were selected encompassing a diversity gradient, ranging from cold temperate to tropical forests. We examined the correlations of tree species richness, composition, and functional diversity, with the evenness of SOC chemical components at a molecular level by 13C nuclear magnetic resonance. Across the range, tree species richness correlated to the evenness of SOC chemical components through tree species composition. The negative correlation of evenness of SOC chemical components with tree species composition, and the positive correlation of evenness of SOC chemical components with tree functional diversity were found. These indicate the larger difference in tree species composition and the lower community functional diversity resulted in the higher heterogeneity of SOC chemical components among the communities. The positive correlation of the evenness of SOC chemical components with the important value of indicator tree species, further revealed the specific tree species contributing to the higher evenness of SOC chemical components in each forest type. Soil fungal and bacterial α-diversity had effect on the evenness of SOC chemical components. These findings suggest that the indicator tree species conservation might be preferrable to simply increasing tree species richness, for enhancing the potential resistance of SOC to decomposition. 相似文献
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正中国高等植物中受威胁物种共3,879种,占评估物种总数的10.84%(覃海宁等,2017)。由于可利用的资源有限,不可能同时保护所有的物种,只能针对亟需保护的物种优先开展保护行动。为便于保护和管理,原国家林业局正式提出了极小种群野生植物(Wild Plant with Extremely Small Populations, 相似文献