Plant diversity patterns in remnant forests and exotic tree species‐based reforestation in active limestones quarries in the Luzon and Mindanao biogeographic sub‐regions in the Philippines

Abstract

The Philippines is both a megadiversity country and a global biodiversity hotspot. The diversity patterns of three major plant groups were assessed: (1) trees (trees and palms), (2) herbs (grasses, shrubs, forbs, ferns), and (3) epiphytes (climbers and epiphytes), by determining the changes in compositional and species richness patterns in two forest conditions, i.e., remnant forests and exotic tree species‐based reforested areas, in active forest over limestone quarries in the Luzon and Mindanao biogeographic sub‐regions of the Philippines. We identified 458 species comprising 266 tree species, 95 herbaceous species and 97 epiphyte species. Of these, 21 species were categorized as threatened species. Species composition differed between remnant forests and exotic tree species‐based reforested areas for tree species and epiphyte species, while composition differences between the Luzon and Mindanao biogeographic sub‐regions were limited to tree species only. Differences in species diversity (in terms of richness) were observed between biogeographic sub‐regions for all plant groups, while differences between forest conditions were found for tree and epiphyte species only. Interestingly, there were significantly fewer numbers of exotic species in bigger remnant forest sites and in older exotic tree species‐based reforested sites, while larger numbers of native species occurred in older than in younger exotic tree species‐based reforested sites. The results emphasize the importance of understanding forest recovery in disturbed ecosystems. Conservation attention should focus on protecting remaining forests and planting native species as part of a forest restoration strategy to enhance faster forest recovery and re‐connecting remnant forest patches.

Review: Biodiversity of forests over limestone in Southeast Asia with emphasis on the Philippines

“…In Peninsular Malaysia, at least 18 karst-dependent plant species have been reported to have gone extinct due to quarrying (Kiew 1991). Limestone is so valuable for creating cement, that governments from developing countries are willing to overlook sustainable limestone quarrying policies just to improve their economy (Bambang and Utomo 2003;Galindon et al 2018;Liew et al 2016). Land-use planning that considers the welfare of poorer communities must be highlighted to address this.…”

Composition and Community Structure of Plant Species in A Secondary Growth Forest in the Central Philippines

“…Forests over limestone like MBFR have been a home for many endemic and threatened species because of their unique environmental conditions, the saline soil properties, dry environment, and shallow soil parent materials, which allowed for the evolution of limestone-adapted species (Querejeta et al 2007). Presence of listed threatened and endemic species should use as reminder even on small remnant forest because they were still impact on the level of biodiversity (Galidon et al 2017). The forest over limestone was considered as home for many endemic species because of their unique environmental conditions (e.g., saline soil properties, dry environment and shallow soil parent materials), which allowed for the evolution of limestone adapted species (Querejeta et al 2007, Fernando et al 2008, Liu and Slik 2014.…”

Biodiversity and ecosystems in Asia: studies and activities of International Long‐Term Ecological Research Network in East Asia and Pacific

“…In their study, Trisurat et al (2018) present a forecast of future changes in ecosystem services in the Lower Mekong Basin by quantifying changes in water yield, while Nguyen et al (2018) review plans to conserve the wetlands in the Vietnamese Mekong Delta by changing the present hydrological management. Galindon et al (2018) compare the status of biodiversity in forests in limestone quarries in different sub-regions of the Philippines with different management histories (reforestation). Leopardas et al (2018) use data from the Japanese 'Monitoring Sites 1000' program to examine broad-scale variations in marine biodiversity patterns in seagrass benthic communities.…”