摘要
土壤微生物群落及其多样性是土壤碳和养分循环的重要生物指标。土地利用变化是影响漫滩生态系统土壤微生物群落组成的主要决定因素。然而,土壤微生物群落的结构和多样性如何响应土地利用变化,以及这些变化的主要驱动因素是什么,仍不清楚。本研究在黄河漫滩进行,以检验土地利用变化对土壤微生物群落的影响。选取了4种土地利用类型(灌丛、农田、草地和森林),其中以灌木地为对照,用磷脂脂肪酸测量了土壤微生物组成和多样性。研究结果表明,土地利用变化显著影响了总细菌、真菌和革兰氏阳性/阴性细菌。与灌丛相比,农田的总磷脂脂肪酸和细菌较高,森林的真菌较高。土壤pH值和全磷是微生物组成的最佳预测因子,分别解释了37%和26%的变异性。土壤全氮和硝态氮是影响微生物多样性的主要因素。花生农田的土壤碳含量、土壤碳储量、磷脂脂肪酸总量和微生物多样性最高,表明漫滩具有巨大的碳汇潜力。这些研究结果表明,黄河漫滩的农田对于维持土壤微生物群落和土壤碳固存至关重要。
Soil microorganisms and their diversity are important bioindicators of soil carbon and nutrient cycling.Land use type is a major determining factor that influences soil microbial community composition in floodplain ecosystems.However,how the structure and diversity of soil microbial communities respond to specific changes in land use,as well as the main drivers of these changes,are still unclear.This study was conducted in the Yellow River floodplain to examine the effects of land use type on soil microbial communities.Four land use types(shrubland,farmland,grassland and forest)were selected,wherein shrubland served as the baseline.We measured soil microbial structure and diversity using phospholipid fatty acids(PLFAs).Land use type significantly affected total,bacterial and fungal PLFAs,and the gram-positive/negative bacterial PLFAs.Compared with shrubland,peanut farmland had higher total and bacterial PLFAs and forest had higher fungal PLFAs.Soil pH and phosphorus were the predominate drivers of microbial PLFAs,explaining 37%and 26%of the variability,respectively.Soil total nitrogen and nitrate nitrogen were the main factors increasing microbial community diversity.Peanut farmland had the highest soil carbon content,soil carbon stock,total PLFAs and microbial diversity,suggesting that farmland has great potential as a carbon sink.Our findings indicated that peanut farmland in the Yellow River floodplain is critical for maintaining soil microbial communities and soil carbon sequestration.
基金
financially supported by the National Natural Science Foundation of China(41930643)
supported by grants from European Union H2020 Marie Skłodowska-Curie Actions(839806)
Aarhus University Research Foundation(AUFF-E-2019-7-1)
Danish Independent Research Foundation(1127-00015B)
Nordic Committee of Agriculture and Food Research.
关键词
细菌
真菌
黄河漫滩
微生物多样性
土壤碳储量
土地利用类型
bacteria
fungi
Yellow River floodplain
microbial community diversity
soil carbon stock
land use type
