Changes in above-/below-ground biodiversity and plant functional composition mediate soil respiration response to nitrogen input

作  者:Zhang DY, Peng YF, Li F, Yang GB, Wang J, Yu JC, Zhou GY, Yang YH*
影响因子:4.434
刊物名称:Functional Ecology
出版年份:2021
卷:35  期:  页码:1171–1182

论文摘要:

  1. Biodiversity loss and changes in plant community composition induced by anthropogenic nitrogen (N) deposition exert profound effects on ecosystem functions. However, limited studies have considered the joint effects of plant community composition, plant species richness, plant functional diversity and soil biodiversity on the dynamics of soil autotrophic and heterotrophic respiration under extra N input.
  2. We addressed this issue by conducting a multilevel Nmanipulation experiment in a Tibetan alpine steppe. Based on soil respiration observations as well as biotic and abiotic measurements under this N addition experiment, we quantified the relative and interactive effects of above/belowground biodiversity, plant community composition and other explanatory variables (environmental factors, plant and microbial properties) on autotrophic and heterotrophic respiration.
  3. Our results showed that the effects of N enrichment via plant productivity, root amount, the proportion of sedge biomass and plant functional diversity explained 71% of the Ninduced variations in autotrophic respiration. With regard to heterotrophic respiration, the combination of N addition, soil pH, plant functional diversity and soil biota diversity accounted for 78% of its variations along the N addition gradient. Further analyses showed that above/belowground diversity loss and changes in plant community composition explained similar variation to that contributed by other factors in both autotrophic and heterotrophic respiration. The declined plant functional diversity and the increased proportion of sedge biomass promoted autotrophic respiration. Conversely, the loss of soil biodiversity together with the decreased plant functional diversity led to the decline of heterotrophic respiration along the experimental N gradient.
  4. Our results highlight that the indirect regulation of N input on ecosystem function through changes in plant community composition and above/belowground biodiversity loss should be considered for better understanding the responses of terrestrial ecosystems to atmospheric N deposition.
全文链接:https://besjournals.onlinelibrary.wiley.com/doi/10.1111/1365-2435.13783