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Rege, A.

Publications and source records attributed to Rege, A..

2 recordsLinked to original sources

Effects of forest cover, temperature and flower abundance on cashew pollinators in the northern Western Ghats, India

Global declines in pollinators pose serious risks for biodiversity, ecosystem functioning, and human well-being. Understanding how landscape structure and climate shape pollinator communities is critical, yet studies that jointly assess these factors in human-dominated tropical landscapes remain scarce. Here, we investigate how forest cover, distance to forest patches, flower abundance, and temperature influence pollinator communities in monoculture cashew plantations that are rapidly expanding in the northern Western Ghats, part of the Western Ghats-Sri Lanka global biodiversity hotspot. We conducted 210 half-hour observation sessions across 30 cashew orchards in Dodamarg, India. At the community level, flower abundance and forest cover positively influenced pollinator richness, number of pollinators, and number of visits. The number of visits showed a unimodal response to temperature, with peaks occurring within narrow, taxon-specific ranges, lower temperatures for birds and higher for insects, likely reflecting physiological constraints. At the species level, flower abundance and temperature emerged as key predictors of occurrence, while three butterfly species occurred more frequently near forest patches. Contrary to expectations, proximity to forest did not reduce ambient orchard temperatures, suggesting limited forest-mediated thermal buffering in our site. Together, these findings highlight the vulnerability of pollination services to both land-use change and rising temperatures. Ongoing conversion of natural forests to cashew monocultures, coupled with climate warming, may erode pollinator communities and jeopardize crop yields in tropical agroecosystems. More broadly, our results underscore the importance of conserving remnant forests and accounting for thermal sensitivity of pollinators to sustain ecosystem services in changing landscapes worldwide.

ecology↗

Native trees within plantations and surrounding forest cover are essential for bird conservation in cashew-dominated landscapes within a biodiversity hotspot

O_LIAnnually, agriculture is responsible for about 60% of tropical forest loss globally. C_LIO_LIstrategies in agricultural landscapes range from enhancing farm-level habitat diversity to retaining forest cover within landscapes. A critical question is determining the relative influence of native trees within farms and forest cover around them on avian diversity, trait responses and species persistence in tree-based systems in landscapes where protected areas are often absent, often the case in lowland tropical forest ecosystems. C_LIO_LIBy sampling birds across gradients of cashew plantation intensification and varying levels of surrounding cashew and forest cover, we examined the relative influence of site- and landscape-level factors on species composition, taxonomic, functional, and phylogenetic diversity, as well as species- and trait-specific responses, and whether phylogenetic relationships among bird species influenced these responses. C_LIO_LIAt the community level, forests, cashew agroforests, and cashew monocultures hosted compositionally different bird communities. Site-level variables, specifically the proportion of native trees, influenced taxonomic and phylogenetic diversity, while landscape-level variables had no effect. None of the predictor variables accounted for the variation in functional diversity. C_LIO_LIAt the species level, site-level variables, specifically the proportion of native trees, and landscape-level variables, particularly cashew cover around plantations, had positive and negative impacts on species responses, respectively. At the trait level, evergreen forest specialists were associated positively with the proportion of native trees and negatively associated with cashew cover. Resident species had a positive association with forest cover. We found a phylogenetic signal in species responses to predictor variables, indicating that closely-related species responded similarly to predictor variables. C_LIO_LISynthesis and applications: To retain taxonomic and phylogenetic diversity and ensure persistence of evergreen forest specialists, it is essential to retain native trees within cashew plantations and maintain surrounding forest cover. Future policies should incentivise the retention and restoration of forest patches and restrict the felling of native trees within cashew plantations. C_LI

ecology↗