Plant Diversity and Abundance Response to the Effects of Soil Properties and Growth Forms in Grasslands

Biodiversity strongly influences key ecosystem processes. However, with ongoing global biodiversity loss, vital ecosystem services are likely to be negatively affected. Studies that monitor biodiversity are thus crucial, especially when performed in relation to environmental conditions. Our study investigated how species diversity and abundance were influenced by soil properties, in association with plant growth forms (i.e., grasses, forbs, and shrubs). The study was conducted across two land-use types: three protected areas (nature reserves) and adjacent unprotected areas. Plant diversity was measured as species richness, and plant abundance was measured as plant density and cover. We used simple and multiple regression analyses, as well as detrended correspondence analysis (DCA) and redundancy analysis (RDA), to elucidate relationships among species richness, plant abundance, growth forms, and soil nutrients. Both species richness and plant abundance were mostly positively associated with soil nutrients across both land-use types. The response was more robust and varied when species were partitioned into growth forms. Growth forms were strong predictors of species richness and abundance across both land-use types, whereas the effects of soil properties were relatively weaker. When growth forms and soil properties were considered jointly, their combined effects strongly predicted species richness and abundance.