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Monitoring the ecological integrity of streams is a challenge, especially in the tropics, which experience high rates of degradation. Multimetric scoring systems have been widely used in other countries in evaluating current stream conditions; however, it has never been done in the Philippines. This study focuses on the development of a benthic macroinvertebrate-based multimetric index for the overall assessment of streams in Mt. Apo, Mindanao, Philippines. The index was used to develop existing physicochemical and biological data obtained during 2010 to 2015 surveys from 15 monitoring sites within the Mt. Apo Geothermal Project (MAGP). Metrics related to benthic macroinvertebrate abundance, richness, composition, functional habit groups, functional feeding groups, and pollution tolerance were screened for their range, temporal stability, sensitivity, discrimination efficiency (DE), redundancy, and responsiveness to anthropogenic impacts. The resulting multimetric index, the Mt. Apo Biotic Index (MABI), is computed as the sum of the individual metric scores after metric transformation using the discrete scoring method DRQ1 (D = discrete, R = reference, Q1 = 25th percentile) of the six core metrics: (1) number of Coleoptera individuals (abundance), (2) number of taxa (richness); (3) [%] Coleoptera taxa (composition), (4) number of sprawler individuals (functional habit group), (5) [%] collector-filterer taxa (functional feeding group), and (6) the Biological Monitoring Working Party Thai version (BMWP-Thai; pollution tolerance). MABI scores were classified into five condition ratings of stream biotic integrity: very poor (6 to 10), poor (11 to 15), fair (16 to 20), good (21 to 25), and excellent (26 to 30). The study demonstrated that the resulting pilot index may provide useful information that will benefit policymakers and resource managers in formulating more comprehensive stream management approaches and conservation plans for priority sites in the region. [ABSTRACT FROM AUTHOR]

Reservoirs are continuous waterscapes that exhibit hydrodynamic characteristics of both lakes and rivers with water flow. These dynamic habitats provide a novel chance to explore the effects of metacommunity dynamics on community structure in relation to environmental, spatial, and temporal processes. We investigated the spatial distribution of spring zooplankton communities in a large reservoir in southern China. We intensively sampled along a longitudinal gradient during early and full spring. We compared the relationship of environmental and spatial variables to the community structure of three zooplankton groups: rotifers, cladocerans, and copepods. The overall composition and abundance of zooplankton groups across longitudinal zones became more heterogeneous with increasing environmental heterogeneity across sampling periods. Multi-level ANOVA and PERMANOVA results showed that rather than homogenize the environment, water flow in late spring increased spatial heterogeneity in the environment and increased the importance of species sorting in shaping the zooplankton community. However, variation partitioning analysis showed that the influence of environmental and spatial variables also varied across the three zooplankton groups likely due to their differences in both physiological and morphological adaptation. Our study shows that metacommunity processes are important in structuring zooplankton communities in reservoir waterscapes that are influenced by flow. [ABSTRACT FROM AUTHOR]

In this paper, we aimed to contribute to the conservation research of a heavily impacted tropical lake ecosystem by characterizing its previously undescribed fish diversity and also elucidating the trophic structure of its fish community. Our study area is Lake Sampaloc, a small crater lake in the southern region of Luzon Island, Philippines. This lake has been heavily used for economic resource functions, such as aquaculture, for decades. Hindrances to the effective implementation of regulatory provisions have produced detrimental ecological effects on the lake, which has recently been declared as "Threatened Lake of the Year 2014". We employed several sporadic fish surveys during a span of two years (2012 to 2014) to identify fishes in the lake. We also used stable isotope analysis to elucidate the trophic level and production reliance of important aquatic consumers. We discovered that the lake fish populations are heavily reliant on periphyton production and are mostly composed of non-native and potentially established invasive fish species. In addition, trophic niche overlaps are observed among non-native fish and native species. For the past three decades, Lake Sampaloc has been classified as eutrophic with high phytoplankton standing biomass. A possible direction for lake rehabilitation research is to investigate ways to change the present turbid state into a clear water system that is predominantly composed of submerged native vegetation. Such a macrophyte-based environment may help sustain the development and recruitment of native juvenile fish and also provide a more diverse functional habitat for fish assemblages that have overlapping trophic niches. [ABSTRACT FROM AUTHOR]