Scattered trees and livestock grazing as keystones organisms for sustainable use and conservation of Mediterranean dehesas

摘要: Abstract Mediterranean scattered oak woodlands support relatively high biological diversity, and provide important ecosystem services. However, there is still a lack of knowledge about livestock-tree-grassland relationships, necessary for effective conservation management in these systems. To address such lacuna, we measured the effects trees grazing animals (livestock vs. wild ungulates, mostly deer) on biomass diversity (and their relationship) herbaceous layer (understory) open holm woodland (known as dehesa) Central Spain, two years. We located 1-ha plots within three different schemes (cattle, sheep wildlife only). Within each plot, randomly selected four focal from which subplot was established directions distances. In subplot, plant biomass, along with microclimatic variables across sites. found rainfall variability affected dehesa system, were nuanced: dry year ( 600 mm annual rainfall) effect enhanced, under livestock exhibited even higher (42%). addition, livestock, particularly cattle, generated more diverse community (52 species m−2). Microsites created by among communities, where alpha (20%) ecotone inter-tree gaps than canopies. species turnover 50% all cases. Biomass (15%) canopies only humid conditions. Legume matter positively related to diversity. concluded that agroforestry practices promoting tree development through silvicultural techniques create microsites, maintaining are needed preserve emblematic ecosystems.