Dominant species play a leading role in shaping community stability in the northern Tibetan grasslands

Abstract

Dominant species may strongly influence biotic conditions and interact with other species, and thus are important drivers of community dynamics and ecosystem functioning, particularly in the stressed environment of alpine grasslands. However, the effects of dominant species on the community stability of different ecosystems remain poorly understood. We examined the temporal stability (2014-2020 year) of above-ground productivity and community stability mechanisms in the northern Tibetan four alpine grasslands (alpine meadow, alpine meadow steppe, alpine steppe, and alpine desert steppe) with changing species composition and dominance. Our results showed that community stability was significantly higher in the alpine meadow than in the other three types of grasslands. This difference was mainly attributed to the higher compensatory effect and selection effect in the alpine meadows. Furthermore, dominant species strongly affected community stability through increasing dominant species stability and species asynchrony. However, species richness had almost little effect. Our findings demonstrate that dominant species, as foundation species, may play leading roles in shaping community stability in the alpine grasslands, highlighting the importance of conserving dominant species for stable ecosystem functioning in these fragile ecosystems under increasing environmental fluctuations.

The phoD-Harboring Microorganism Communities and Networks in Karst and Non-Karst Forests in Southwest China

“…A higher calcium content reduces the communication and movement abilities of some microbial taxa [65,74]. In the present study, the ExCa 2+ content in karst forest soils was higher than that in non-karst forest soils [70], and a stronger effect of ExCa 2+ content on the abundance of phoD-harboring microorganism taxa was observed in karst forest soils.…”

“…Seasonal variation had no marked effect on the diversity index of phoD-harboring microorganisms in karst forest soils, but it did have a marked effect on non-karst forest soils. This suggests that phoD-harboring microorganisms were more active in the soil P cycle and more sensitive to seasonal changes in non-karst forest ecosystems, which is closely related to their low AP [65,66] The community structures of the phoD-harboring microorganisms in the two forest soils were influenced by a multitude of environmental factors [67,68]. In the present study, AP content influenced the diversity and structure of phoD-harboring microorganisms.…”

“…Streptomycetales, as a non-dominant species [63], were significantly higher in karst (1.22%) than in non-karst forest soils (0.038%). Thus, dominant species in non-karst forest soils inhibited the growth of non-dominant species, resulting in low Shannon-Wiener and Evenness indices of phoD-harboring microorganisms [64,65]. Lower Shannon-Wiener and Evenness indices of phoD-harboring microorganisms indicated that microbial communities in non-karst forest ecosystems were unstable and weak in response to environmental changes.…”

Effect of Forest Fires on the Alpha and Beta Diversity of Soil Bacteria in Taiga Forests: Proliferation of Rare Species as Successional Pioneers

“…Each sample plot, including three plots of 20 m × 20 m, underwent sampling using a 5-point mixed sampling method. Soil samples were collected from a depth of 0-20 cm, excluding surface layers of withered material and humus [24]. After thorough mixing and removal of debris and rhizomes, the samples were sieved through a 2 mm sieve and stored in a cold place for further use.…”

“…Dominant species play a vital role in ecosystems, exhibiting strong responses to environmental changes under extreme conditions and interacting with other species. They possess a higher resource utilization capacity and typically occupy a substantial portion of the ecological niche space, contributing to ecosystem balance and stability through increased stability and asynchrony [24]. Rare species are equally crucial for species coexistence and biodiversity maintenance in forest ecosystems.…”