Naiman Desertification Research Station, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Donggang West Road 320, Lanzhou City, Gansu Province 730000, China; Key Laboratory of Stress Physiology and Ecology in Cold and Arid Regions, Gansu Province, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, Gansu, China.
Naiman Desertification Research Station, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Donggang West Road 320, Lanzhou City, Gansu Province 730000, China; University of Chinese Academy of Sciences, Beijing 100049, China.
Sci Total Environ. 2024 May 15;925:171765. doi: 10.1016/j.scitotenv.2024.171765. Epub 2024 Mar 17.
Plant communities and soil microbiomes play a crucial role in regulating ecosystem multifunctionality (EMF). However, whether and how aboveground plant diversity, belowground soil microbial diversity and interactions with environmental factors affect EMF in sandy grasslands under climate change conditions is unclear. Here, we selected 15 typical grassland communities from the Horqin sandy grassland along temperature and precipitation gradients, using the mean annual temperature (AMT), mean annual precipitation (AP), soil temperature (ST), soil water content (SW) and pH as abiotic factors, and plant diversity (P) and soil microbial diversity (S) as biodiversity indicators. The effects of biodiversity and abiotic factors on individual ecosystem functions and EMF were studied. We found that P and its components, plant species richness (S), species diversity (P) and genetic diversity (G), had significant effects on aboveground biomass (AGB) and major factors involved in ecosystem nitrogen cycling (plant leaf nitrogen content (PLN) and soil total nitrogen content (STN)) (P < 0.05). Soil fungal diversity (F) has a greater impact on ecosystem function than soil bacteria (B) and archaea (AB) in sandy grasslands and mainly promotes the accumulation of soil microbial carbon and nitrogen (MBC, MBN) (P < 0.05), STC and STN (P < 0.01). P and two types of S (F and AB) significantly regulated EMF (P < 0.01). Among the abiotic factors, soil pH and SW regulated EMF (P < 0.05), and SW and ST directly drove EMF (P < 0.05). P drove EMF significantly and indirectly (positively) through soil pH and ST (P < 0.001), while S drove EMF weakly and indirectly (negatively) through AP and P (P > 0.05). P was a stronger driving force on EMF than S. These results improve our understanding of the drivers of multifunctionality in sandy grassland ecosystems.
植物群落和土壤微生物在调节生态系统多功能性（EMF）方面发挥着关键作用。然而，在气候变化条件下，沙质草原地上植物多样性、地下土壤微生物多样性以及与环境因素的相互作用是否以及如何影响 EMF 尚不清楚。在这里，我们沿着温度和降水梯度从科尔沁沙地选择了 15 个典型的草原群落，以年平均温度（AMT）、年平均降水量（AP）、土壤温度（ST）、土壤水分含量（SW）和 pH 作为非生物因素，以植物多样性（P）和土壤微生物多样性（S）作为生物多样性指标。研究了生物多样性和非生物因素对单个生态系统功能和 EMF 的影响。我们发现，P 及其组成部分，植物物种丰富度（S）、物种多样性（P）和遗传多样性（G），对地上生物量（AGB）和生态系统氮循环的主要因素（植物叶片氮含量（PLN）和土壤总氮含量（STN））有显著影响（P<0.05）。在沙质草原中，土壤真菌多样性（F）对生态系统功能的影响大于土壤细菌（B）和古菌（AB），主要促进土壤微生物碳和氮（MBC、MBN）的积累（P<0.05），STC 和 STN（P<0.01）。P 和两种 S（F 和 AB）显著调节 EMF（P<0.01）。在非生物因素中，土壤 pH 值和 SW 调节 EMF（P<0.05），SW 和 ST 直接驱动 EMF（P<0.05）。P 通过土壤 pH 值和 ST 对 EMF 产生显著而间接（正向）的驱动作用（P<0.001），而 S 通过 AP 和 P 对 EMF 产生微弱而间接（负向）的驱动作用（P>0.05）。P 对 EMF 的驱动力强于 S。这些结果提高了我们对沙质草原生态系统多功能性驱动因素的理解。
