Land use and climate shape amphibian multidimensional diversity and conservation in a coffee agroforestry landscape, Western Ghats

Vijay Karthick , Siva Dass, Vishal Gopal Sadekar, Rohit Naniwadekar, Anand M Osuri

Shade coffee agroforests are potential refuges for biodiversity in human-modified tropical landscapes. However, biodiversity is influenced by coffee cultivation methods and climates, both of which vary widely and are increasingly dynamic. One significant but understudied dynamic is the shift in cropping system from arabica (Coffea arabica) to robusta (C. canephora), which alongside deforestation and climate change, is reshaping global coffee landscapes. We compared land use types (secondary rainforest, arabica agroforest, robusta agroforest) and climate zones (coffee in wet vs. dry zones) for amphibian abundance, community composition, multidimensional diversity (taxonomic, functional, phylogenetic), and ecologically-sensitive and conservation-priority species in India's Western Ghats mountains. We sampled amphibians using line transects (total 12.9 km), collected primary and secondary data on 12 functional traits, geographic distributions, threat status, phylogeny, and estimated multidimensional diversity (Hill-Chao numbers q = 0–2) and species occurrence probabilities across land uses and climate zones. While overall amphibian abundance and richness (q = 0) were similar across land uses and climates, the secondary rainforest had distinct community composition, higher multidimensional diversity (q = 1, 2), and higher occurrence probabilities of stream breeding and threatened-endemic species than coffee. Amphibian multidimensional diversity (q = 1, 2) was generally higher in arabica than robusta agroforest in both climate zones, and alongside stream breeding and threatened-endemic species was lower in dry than wet zones. Our findings suggest that conversion from arabica to robusta systems and climate drying can diminish amphibian multidimensional diversity, and highlight the value of safeguarding and restoring forests and streams for ecologically-sensitive and conservation-priority species in changing coffee landscapes.