Enrico Replan

Lakeshore grasslands are important components of freshwater ecosystems, providing habitat for wildlife, forage resources, shoreline protection, and other ecosystem functions. Although these ecosystems contribute substantially to biodiversity conservation and ecosystem functioning, studies describing their vegetation composition and diversity remain scarce in many tropical regions. This knowledge gap is particularly evident along the shores of Laguna de Bay, where information on lakeshore vegetation remains limited. This study aimed to characterize the floristic composition, diversity, and spatial variation of lakeshore grassland vegetation in Barangays San Antonio and Tagumpay, Bay, Laguna, Philippines. Vegetation sampling was conducted in August 2025 using nested quadrats established along five transects. Twenty-eight quadrats were surveyed and aggregated into seven sampling stations across two barangays. Species diversity was evaluated using the Shannon–Wiener Index, Simpson’s Diversity Index, and Pielou’s Evenness Index. Thirty-five plant species across 18 genera and 10 families were documented. Poaceae was the most represented family and formed the structural backbone of the vegetation community. The vegetation was largely composed of widespread, disturbance-tolerant taxa. The grass species Brachiaria mutica, Sorghum halepense, and Echinochloa crus-galli exhibited the highest importance values and contributed substantially to overall vegetation cover and density. Several introduced and invasive species, including Lantana camara, Cyanthillium cinereum, and Commelina diffusa were recorded across multiple sampling sites. Species diversity was generally moderate (H′ = 2.10–2.32), while spatial analyses revealed localized variation in species composition and diversity among sampling stations, with no significant spatial autocorrelation. The findings provide baseline information for future monitoring, conservation planning, and management of lakeshore vegetation in Laguna de Bay and contribute to a better understanding of plant community dynamics in disturbed tropical lakeshore ecosystems.

Tropical lowland forests, particularly lowland evergreen rainforests, are considered the most luxuriant among all plant communities and harbour the majority of the world’s rich terrestrial biodiver...

Anthropogenic disturbance is a major driver of biodiversity loss and structural degradation in tropical forests. Understanding how disturbance alters community composition and forest structure is essential for effective conservation management, particularly within protected landscapes where human–environment interactions remain pervasive. This study examined patterns of ecological homogenization and structural simplification across disturbance gradients in the Lagonoy Natural Biotic Area. Vegetation surveys were conducted across stratified sampling plots representing low, moderate, and high disturbance conditions. Tree species composition, structural attributes, and environmental indicators were assessed to evaluate how anthropogenic pressure influences forest community organization. A total of 121 vascular plant species representing 59 families were recorded across sampling plots. Species richness and diversity indices declined with increasing disturbance intensity. Low-disturbance plots exhibited higher basal area, greater tree density in larger diameter classes, and more heterogeneous species assemblages. In contrast, highly disturbed plots were dominated by disturbance-tolerant and early-successional taxa and showed reduced structural complexity. Ordination analysis revealed clear compositional separation among disturbance classes, showing increasing similarity in species composition across plots with increasing anthropogenic pressure. These compositional patterns were statistically supported by PERMANOVA and PERMDISP analyses, confirming reduced beta diversity and increased ecological homogenization under high-disturbance conditions. These findings highlight the importance of protecting interior forest areas to maintain biodiversity and structural integrity in tropical protected landscapes.

The Amnay River Delta in Sablayan, Occidental Mindoro, Philippines, is a dynamic tropical coastal system shaped by monsoon-driven circulation, high rainfall, and substantial sediment delivery from upstream watersheds. This study examines the hydrodynamic and sediment transport processes of the delta and adjacent coastal waters using a two-dimensional numerical model developed with Delft3D. High-resolution bathymetric data from echo-sounding surveys, combined with GEBCO 2019–2020 datasets, were used to construct the computational grid, while tidal forcing was obtained from the TPXO 8.0 global tide model. Three-hourly wind data representing northeast and southwest monsoons and river discharge data from the PHIL-LiDAR 1 program—including a peak flow of 264.5 m³/s—were included. Sediment transport simulations assumed 5 kg/m³ of non-cohesive sediments. Nine scenarios assessed the effects of tides, monsoon winds, river discharge, and sediment input. Results show weak, non-uniform residual currents under no-wind conditions, with localized circulation near the river mouth. Southwest monsoons produced stronger flows, current reversals, and wider sediment dispersion. Sediment plumes indicate estuarine accumulation and sandbar formation, consistent with shoreline progradation of up to 200 m over 15 years. The study highlights integrated modeling for delta evolution, sediment management, and adaptive coastal planning

Riparian vegetation plays a critical role in maintaining ecological integrity along river corridors, yet it is highly sensitive to changes in hydrological and geomorphic conditions, particularly in sediment‐influenced tropical river systems. In many Philippine rivers, increased sediment deposition and landscape disturbance have altered riparian structure and floristic composition, underscoring the need for site‐specific baseline assessments. This study aimed to document the floristic composition, vegetation structure, and spatial patterns of riparian vegetation along the downstream reach of the Amnay River in Occidental Mindoro, Philippines, as a baseline for understanding current riparian conditions in a sediment‐influenced river corridor. Vegetation surveys were conducted using transects and quadrats established along the riverbanks, where species composition, growth form, and structural attributes were recorded. Species importance values and diversity indices were calculated to characterize vegetation dominance and diversity patterns across sampling sites. Riparian vegetation communities were mapped to describe spatial distribution and fragmentation. A total of 125 plant species representing 40 families were recorded, with vegetation dominated by herbaceous and disturbance‐tolerant taxa, particularly members of Poaceae and Fabaceae. Woody vegetation was limited and occurred mainly as isolated remnant patches, resulting in low vertical complexity and fragmented spatial structure. Species diversity varied among sampling sites, reflecting localized differences in substrate stability and vegetation cover. The findings provide a baseline characterization of riparian vegetation in a sediment‐influenced tropical river system and highlight the persistence of remnant woody vegetation within an otherwise simplified riparian corridor. This baseline information is essential for future monitoring, comparative studies, and the evaluation of riparian management and restoration efforts.

Sustainable management of mangrove forests for ecotourism requires knowledge on geospatial biodiversity to ensure that the rehabilitation and conservation interventions are appropriate to its ecological condition. This study aims to assess the floristic diversity of the species in the Lagadlarin Mangrove Forest, Lobo, Batangas, Philippines, and integrate the geospatial analysis using a geographic information system as a basis for the sustainable conservation and management of mangroves for ecotourism. The assessment was conducted through a systematic nested quadrat sampling technique by establishing 20 quadrats measuring 10 x 10 m. The area has a very low species diversity based on Shannon-Weiner’s Index (1.82) and Margalef’s Richness Index (0.87). In terms of the species distribution and abundance, the area measured high on Pielou’s Evenness Index (0.61) and Simpson’s Dominance Index (0.78). There are 16 true mangrove species documented in the area, one vulnerable and two near-threatened species. The species that were found dominating the area based on the computed Importance Value are Avicennia marina ssp. rumphiana (89.20%), A. marina ssp. marina (32.85%), Excoecaria agallocha (23.92%), and Acacia farnesiana (21.86%), an invasive species. The enrichment and rehabilitation zones were determined based on the geospatial analysis of the distribution of species diversity for sustainable management of mangrove ecotourism.

Molawin River is experiencing water quality degradation over time. Efforts were made to help rehabilitate this river to maintain its ecology and biodiversity. The main objectives of this research are: to identify and document water filtering plants (riparian flora) both present in terrestrial and aquatic ecosystems in the Molawin River and to pinpoint the sources and community perception that defies the idea of riparian flora species as potential water filtering plants in the Molawin River. Documentation of dense riparian flora present in the Molawin River was conducted in order to study its phytoremediation potential for water purification. A total of 107 morpho-species belonging to 94 genera from 56 families was recorded. The most common flora species was Commelina diffusa, Cyperus flabelliformis and Costus speciosus. A household survey and key informant interview were employed. The idea of riparian flora as a potential water purifying plants is facing four main challenges. First, there is a low conservation interest with the water resource, as this is not the primary source of water for them. Secondly, the presence of anthropogenic factors severely affecting the area. Thirdly, the high rate of encroachment of the invasive plants aggravates the conditions of the river. Finally, the lack of institutional support that can integrate riparian flora species in watershed management and rehabilitation planning.

The alarming presence of COVID-19 challenged the United Nations’ (UN) Sustainable Development Goal 2 and made the World Health Organization (WHO) declare a public health emergency of international concern. Imposed lockdowns disrupted the supply and demand chain of the food systems, hence affecting food security. This research would like to know and assess the early effect (two months after the lockdown) of the enhanced community quarantine on food security in the Philippines. An online survey was employed participated by 331 household representatives using a survey instrument containing food security assessment, household socio- demographic characteristics, behavioral responses covering food purchase and consumption behavior, and emergency measure adoption. Statistical tests were applied: Mann-Whitney U test to know the behavioral response of the food secure vs. food insecure households, as well as the phi coefficient and Cramer’s V test to determine and assess the parameters that plays important role in food security during this period. Results showed that 73% of the respondents were food insecure. The early effect of the lockdown was seen in the behavioral responses, significant differences between food secure and insecure households were found in age, income, and food purchase behavior. Parameters associated with food security are age, income, food allocation, expectations on the livelihood impact and change in expenditure, and the adoption motivations in practicing backyard gardening. The stress evaluation revealed that while Filipinos tried to cope, an increased level of anxiety was experienced. The need for clear measures in terms of preparedness in any pandemic situation was heightened. These findings are significant in providing benchmark information on food security during a pandemic.

Calauit island is one of the islands in the Calamian Group of Islands in northern Palawan. The island is truly blessed with bountiful mangrove resources which provide the Tagbanuas enormous economic and ecological importance. Not known to many, Calauit island became the exit point of typhoon Yolanda causing tremendous damage to mangrove area. The study assessed the extent of damage and the recovery potential of Calauit mangrove forests from the devastation of Typhoon Yolanda. Ten sampling quadrats were established in areas where trees were observed to be 100% defoliated. Individual trees (≥ 1cm diameter) inside each quadrat were measured and evaluated based on the assessment matrix developed in this study. Results of our assessment revealed serious damage of mangroves in Calauit island. About 60% of the mangrove forests was severely affected by Typhoon Yolanda. Eight months after the typhoon, 21% of the trees have fully-recovered crown (all branches were able to develop leaves), 70% are still defoliated and 22% were already dead. Four of the 10 quadrats showed high potential for recovery as evidenced by a lot of seedlings (≥ 25 seedlings) to serve as new regenerations. Conversely, there are four quadrats without any seedling recorded. Three monitoring plots were established for continuous monitoring of the recovery of the mangrove ecosystems. A course of actions was recommended to facilitate the recovery of mangroves in Caluit island, and to bring back the economic benefits from the forest.