Krizler Cejuela Tanalgo

Invasive earthworms erode soil biodiversity: a meta-analysis.

Biological invasions pose a serious threat to biodiversity and ecosystem functioning across ecosystems. Invasions by ecosystem engineers, in particular, have been shown to have dramatic effects in recipient ecosystems. For instance, invasion by earthworms, a below-ground invertebrate ecosystem engineer, in previously earthworm-free ecosystems alters the physico-chemical characteristics of the soil. Studies have shown that such alterations in the soil can have far-reaching impacts on soil organisms, which form a major portion of terrestrial biodiversity. Here, we present the first quantitative synthesis of earthworm invasion effects on soil micro-organisms and soil invertebrates based on 430 observations from 30 independent studies. Our meta-analysis shows a significant decline of the diversity and density of soil invertebrates in response to earthworm invasion with anecic and endogeic earthworms causing the strongest effects. Earthworm invasion effects on soil micro-organisms were context-dependent, such as depending on functional group richness of invasive earthworms and soil depth. Microbial biomass and diversity increased in mineral soil layers, with a weak negative effect in organic soil layers, indicating that the mixing of soil layers by earthworms (bioturbation) may homogenize microbial communities across soil layers. Our meta-analysis provides a compelling evidence for negative effects of a common invasive below-ground ecosystem engineer on below-ground biodiversity of recipient ecosystems, which could potentially alter the ecosystem functions and services linked to soil biota.

A Preliminary study on bats in a Small-scale Mining Site in South central Mindanao, Philippines

Land-use change and its associated activities have been strongly linked to the decline of many bat species populations glob- ally. This study was conducted with a primary goal to document the bat diversity on a small scale mining site in Baranggay Kinayao, Bagumbayan, Sultan, Kudarat, Philippines. A total of 227 individuals were identified, representing two families (Pteropodidae and Hipposideridae), eight genera, and eight species of bats. Three species are endemic to the Philippines namely Haplonycteris fischeri, Ptenochirus jagori, and the Vulnerable Megaerops wetmorei. Pteropodid Cynopterus brachyotis were found to be the most dominant and tolerant species in the area compared to all species combined. In addition, a significant decrease in bat activity was noted during active blasting period, as evidenced by a low capture rate compared to non-blasting period. This preliminary finding suggests the need for further exploration of how human-induced noise increase the effects of the land-use change to bat diversity and population.