Plant communities of high-Andean bofedal wetlands across a trans-Andean transect in southern Peru

Abstract

Aims: Ecosystems of the Tropical Andes include plant communities above 4,000 m in elevation, associated with wetlands known as bofedales. To enhance our understanding of them, we surveyed bofedal plant communities in the Peruvian Andes. Questions: Which are the most common bofedal plant communities, and what are their main characteristics? Study area: An east-to-west 68 km megatransect in Ayacucho and Huancavelica departments in Peru, the area of influence of a gas pipeline. Methods: We surveyed 127 (1 m × 1 m) permanent plots annually between 2017 and 2019 to assess plant communities, calculated diversity metrics, and applied non-parametric hypothesis testing analysis of similarities and multivariate analyses to the data. Results: We identified 13 plant communities with 3.5 to 11.7 mean species richness. Only seven were statistically different; the other six were rare and require additional surveys to define their status as independent communities. The Distichia muscoides-dominated community was found in most sites (90%), plots (55%), and along the entire elevational range we studied. D. muscoides, Plantago tubulosa, and Rockhausenia pygmaea were the most frequent species in the studied bofedales (in 30 of 31 sites). These species are usually cushion or carpet forming, so average plant cover was high in most plant communities where they occurred (89–98%). The seven plant communities (dominated by D. muscoides, R. pygmaea, Plantago tubulosa, P. rigida, Lachemilla diplophylla, Aciachne pulvinata and Juncus stipulatus) were consistent in their structural and compositional characteristics and maintained differences between them during our three-year study. Conclusions: We show that bofedal plant communities in the southern Peruvian Andes are more heterogeneous than the four broad types previously reported. This heterogeneity occurs at local site levels but also at landscape and regional scales. We highlight the importance of considering this heterogeneity when discussing and implementing management, restoration, and conservation actions in bofedales. Taxonomic reference: WFO (2024)