Soil arthropods contribute to terrestrial ecosystem functions and services. Previous studies mainly focused on specific arthropod and non-arthropod taxonomic groups at various geographic scales. However, the patterns of overall soil arthropod community composition and the drivers of taxonomic diversity at different geographic scales remain unevaluated.
In a study published in Catena, researchers from Xishuangbanna Tropical Botanical Garden (XTBG) examined the diversity and distribution patterns of soil arthropods in four forests with different latitudinal distributions in Yunnan Province, southwestern China.
To explain the distribution patterns of soil arthropods at both local (relatively small habitat patches) and regional (latitudinally)scales, the researchers explored two hypotheses: (1) habitat heterogeneity hypothesis (spatial complexity and variability of habitat allow many species to coexist), and (2) more individuals hypothesis (the amount of resources in itself, regardless of their spatial heterogeneity, increases overall soil arthropod richness and abundance).
The researchers collected soil arthropod samples (identified to family or subfamily level) from four locations ( tropical Bubeng; tropical Nabanhe; subtropical Ailaoshan; subalpine Lijiang) across different latitudes in Yunnan. They then measured soil physicochemical properties to test the relative importance of environmental factors at different spatial scales.
They found that soil arthropod richness and abundance increased with increasing latitude, which contrasted with the pattern generally known for plants and aboveground animals. At the regional scale, litter biomass (resources) explained species richness and abundance, consistent with the more individuals hypothesis. While at the local scale, other soil physicochemical properties were more important, supporting the habitat heterogeneity hypothesis.
However, the relative importance of individual soil properties was highly dependent on sites, suggesting that environmental factors at one site do not necessarily reflect those at other sites with different latitudes.Nestedness was not a major component of the regional-scale β-diversity.
“Our study provides the first evidence that regional-scale β-diversity patterns of soil arthropods also follow the same patterns as other groups of terrestrial and freshwater organisms.It highlights the importance of considering different spatial scales and environmental factors to better understand and conserve soil biodiversity,” said Yang Xiaodong.
Contact
Akihiro Nakamura ; YANG Xiaodong
Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, Yunnan 666303, China
E-mail: a.nakamura@xtbg.ac.cn; yangxd@xtbg.ac.cn
Published: 01 October 2024