Th e biodiversity of non-volant small mammals along an extensive subtropical elevational gradient was studied for the fi rst time on Gongga Mountain, the highest mountain in Hengduan Mountain ranges in China, located in one of the 25 global biodiversity hotspots. Non-volant small mammals were replicate sampled in two seasons at eight sampling sites between 1000 and 4200 m elevation on the eastern slope of Gongga Mountain. In all, 726 individual small mammals representing 25 species were documented in 28 800 trap nights. Th e species richness pattern for non-volant small mammals along the elevational gradients was hump-shaped with highest richness at mid-elevations. However, diff erent richness patterns emerged between endemic and non-endemic species, between larger-ranged and smaller-ranged species and between rodents and insectivores. Temperature, precipitation, plant species richness and geometric constraints (middomain eff ect) were most signifi cant in explaining species richness patterns. Based on the analysis of simple ordinary least squares (OLS) and stepwise multiple regressions, the overall richness pattern, as well as the pattern of insectivores, endemic species and larger-ranged species showed strong correlation with geometric constraint predictions. However, nonendemic species richness was more strongly correlated with temperature, while rodent richness was correlated with plant species richness. Our study shows that no single key factor can explain all richness patterns of non-volant small mammals. We need to be cautious in summarizing a general richness pattern of large species groups (e.g. small mammals or mammals) from species in smaller groups having diff erent ecological distributions and life histories. Elevational richness patterns and their driving factors for small mammals are more likely dependent on what kind of species we study.
Summary1. Arbuscular mycorrhizal fungi (AMF) are key regulators of ecosystem processes, yet how their biodiversity works in ecosystems remains poorly understood. 2. We documented the extent to which taxonomic resolution influenced the effect of biodiversity of AMF taxa on plant performance (growth, nutrient uptake and stress tolerance) in a meta-analysis of 902 articles. 3. We found that the effect of biodiversity of AMF taxa depended on taxonomic resolution. Plant performance was positively promoted by AMF family richness, while no effect was found for fungal species richness. In addition, negative effect was found between AMF phylogenetic diversity and plant growth. This pattern can be explained by functional conservatism within AMF families and functional differentiation among AMF families. 4. Synthesis. Conservation of AMF communities to maintain a full complement of ecosystem functions requires the presence of diverse families and not simply diverse species within a family. This finding may be of key importance for the function of ecosystems under various environmental perturbations to which AMF families may respond differently.
Obligate aerobic AMF taxa have high species richness under waterlogged conditions, but their ecological role remains unclear. Here we focused on AM fungal mediation of plant interactions in a marshland plant community. Five cooccurring plant species were chosen for a neighbor removal experiment in which benomyl was used to suppress AMF colonization. A Phragmites australis removal experiment was also performed to study its role in promoting AMF colonization by increasing rhizosphere oxygen concentration. Mycorrhizal fungal effects on plant interactions were different for dominant and subdominant plant species. AMF colonization has driven positive neighbor effects for three subdominant plant species including Kummerowia striata, Leonurus artemisia, and Ixeris polycephala. In contrast, AMF colonization enhanced the negative effects of neighbors on the dominant Conyza canadensis and had no significant impact on the neighbor interaction to the dominant Polygonum pubescens. AM colonization was positively related to oxygen concentration. P. australis increased oxygen concentration, enhanced AMF colonization, and was thus indirectly capable of influencing plant interactions. Aerobic AM fungi appear to be ecologically relevant in this wetland ecosystem. They drive positive neighbor interactions for subdominant plant species, effectively increasing plant diversity. We suggest, therefore, that AM fungi may be ecologically important even under waterlogged conditions.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.