Mound‐building ants increase the proportion of Gramineae in above‐ground vegetation and the soil seed bank in alpine meadows

Abstract

Question: The impact of ants on the vegetation and soil seed bank of alpine meadows on the Qinghai-Tibetan Plateau is largely unknown. We questioned how the moundbuilding ant, Camponotus herculeanus, affects the above-ground vegetation, the soil seed bank and physico-chemical properties of the soil. Location: An alpine meadow in the northeast margin of the Qinghai-Tibetan Plateau (37°40′ N, 102°32′ E), China. Methods: We used field and greenhouse studies to determine the above-ground vegetation parameters and soil physico-chemical properties, and the soil seed bank composition under the mound (UM), the herbage circle at about 10 cm width around the outside of the mound (mound edge, ME) and the area 1 m from the center of the mound (control). Results: (a) The mound edge had higher vegetation height, greater above-ground biomass, lower vegetation coverage and lower plant richness than controls; (b) Gramineae had a higher total importance value, which was based on the height, cov

Reduced plant species diversity and soil carbon and nitrogen contents driven by vegetation patchiness in alpine meadows

“…The sampled plants in each quadrat were divided into four functional groups: grasses, sedges, legumes and forbs. The importance values (IV) of plant species and functional groups were estimated using formula () based on measured data of plant species' height, coverage, and biomass in each quadrat (Zhao et al., 2020):$$$$ \mathrm{IV}=\left(\mathrm{Rh}+\mathrm{Rc}+\mathrm{Rb}\right)/3, $$$$where Rh, Rc and Rb represent the relative height, relative coverage and relative biomass of different plant species, respectively. Rh (Rc or Rb) was determined by dividing each plant's height (coverage or biomass) by the total height (coverage or biomass) of all plant species present in the respective quadrat.…”

Biodiversity in mountain soils above the treeline

“…Interestingly, a high number of social parasitic ant species are reported from alpine habitats without a clear explanation so far, except that the harsher environment might positively select for such life history traits (Dunn et al ., 2009; Schifani et al ., 2021). In alpine grasslands, the effect of ants on soils is mostly related to nest construction, since most taxa build their nests in the soil, causing soil turnover as well as nutrient accumulation and influencing the vegetation (Wang et al ., 2017; Zhao et al ., 2020). Ants strategically establish their nests beneath rocks, leveraging the warmth absorption and insulation (McCaffrey & Galen, 2011).…”