Does pH matter for ecosystem multifunctionality? An empirical test in a semi‐arid grassland on the Loess Plateau. (11th May 2022)

• Record Type: Journal Article
• Authors: Wei, Yanan; Jing, Xin; Su, Fanglong; Li, Zhen; Wang, Fuwei; Guo, Hui
• Is Part Of: Functional ecology. Volume 36:Number 7(2022)
• Page Start: 1739
• Page End: 1753
• Publication Date: 2022-05-11
• Subjects: alkaline soil -- ecosystem functioning -- global change experiment -- grassland -- multifunctionality -- soil acidification; Ecology -- Periodicals; 574.505
• DOI: 10.1111/1365-2435.14057
• Languages: English
• ISSNs: 0269-8463

Abstract

Abstract: Globally, higher inputs of acid deposition and anthropogenic reactive nitrogen cause lower pH in soils, that is, soil acidification, which may broadly influence both above‐ and below‐ground biota and their habitats. However, we know little about the consequences of soil acidification for a wide range of ecosystem functions and services (i.e. ecosystem multifunctionality). Here, we examined the impacts of short‐term soil acidification on 19 ecosystem functions relevant to ecosystem primary productivity and the cycling and/or storage of soil carbon (C), nitrogen (N) and phosphorus (P) using a 2‐year acid addition field experiment in a semi‐arid grassland on the Loess Plateau, China. We further assessed the potential pathways through which plant diversity and soil processes drive ecosystem multifunctionality (hereafter, EMF, EMF‐productivity, EMF‐C, EMF‐N, EMF‐P). We found that soil acidification suppressed 15 of the 19 individual ecosystem functions. By accounting for other biotic and abiotic confounding variables, we found that soil pH remains to be the dominant one explaining the variation in EMF, EMF‐C and EMF‐N. The underlying mechanisms of soil pH driving multifunctionality varied substantially among the groups of multifunctionality. Specifically, plant‐related variables (i.e. species richness and abundance) exhibited stronger mediating effects on EMF‐productivity and EMF‐C than did soil properties (i.e. soil K +, Ca 2+, Mg 2+ and Na + ions) and microbial‐related variables (i.e. microbial biomass C and N). Our findings provide empirical evidence that short‐term soil acidification could have greater negative effects on ecosystem multifunctionality than expected in the arid and semi‐arid areas where alkaline soils are commonly seen. This study also indicates that more attention should be paid to the biological mechanisms mediating multifunctional ecosystems under a global change scenario in the future. Read the free Plain Language Summary for this article on the Journal blog. Abstract : Read the free Plain Language Summary for this article on the Journal blog. 摘要: 全球范围内，酸沉降和人为活性氮输入的增加导致土壤pH值降低，即土壤酸化，这可能广泛地影响地上和地下生物及其生境。然而，我们关于土壤酸化对多种生态系统功能和服务(即生态系统多功能性)的影响知之甚少。 我们通过在黄土高原一块半干旱草地开展的2年野外酸添加试验，研究了短期土壤酸化对19个生态系统功能的影响，这些功能与生态系统初级生产力以及土壤碳、氮、磷的循环和储存相关。我们进一步评估了土壤酸化通过植物多样性和土壤过程驱动生态系统多功能性(功能分组包括:EMF、EMF‐productivity、EMF‐C、EMF‐N、EMF‐P)的潜在途径。 我们发现，土壤酸化抑制了19种生态系统功能中的15种。在考虑其他生物和非生物混杂变量后，我们发现土壤pH值仍然是解释EMF、EMF‐C和EMF‐N变化的主导因素。土壤pH值驱动多功能性的潜在机制在不同的功能分组之间存在较大的差异。其中，植物相关变量(物种丰富度和丰度)对EMF‐productivity和EMF‐C的调节作用强于土壤性质(土壤K + 、Ca 2+ 、Mg 2+ 和Na + 含量)和微生物相关变量(微生物生物量碳和氮)。 我们的研究结果表明，在碱性土壤普遍存在的干旱和半干旱地区，短期土壤酸化可能对生态系统的多功能性产生比预期更大的负面影响。该研究也表明，在未来的全球变化情景下，生态系统多功能性的生物调节机制应引起更多的关注。