Mangrove Diversity Research Articles

Sarcosaprophagous flesh flies (Diptera: Sarcophagidae) are less diverse in Amazon Forest than mangroves in Northeast Brazil: preliminary insights about environmental heterogeneity

ABSTRACT Environmental heterogeneity can affect the diversity of arthropods, resulting in a positive relationship in most studies, including of some Diptera groups. We investigated the diversity patterns of Sarcophagidae fauna in two phytophysiognomies with inferences about the environmental heterogeneity. In our hypothesis, the flesh flies have higher diversity in more heterogeneous environments than in the more homogeneous one. The study was performed in São Luís Island, state of Maranhão, Northeast Brazil. In total, we found 1482 specimens, of which 402 were males, representing six genera and 26 species. Peckia (Euboettcheria) collusor (Curran and Walley) was the most abundant species. The mangrove community was more diverse than the forest community. Species replacement contributes more significantly to the difference in species composition between environments than richness difference does, with higher values of dissimilarity of taxonomic diversity. Our data show that sarcosaprophagous flesh flies have a preference for open and sunny environments, implying greater diversity in mangroves rather than in forested areas. The negative relationship between species richness/abundance and vegetation cover in our study corroborates flesh flies’ preference for open environments. Our data show a tendency to refute the environmental heterogeneity hypothesis. The mangrove fauna, especially Diptera communities, has received less attention. Nevertheless, mangrove has the potential to shelter high species richness, highlighting the need for further studies and conservation plans for these areas.

Floristic composition, structure, and diversity of mangroves in the coastal areas of Mabini, Davao de Oro, Philippines

Abstract. Manual AMB, Gabato NAS, Jetuya QB, Alimbon JA. 2022. Floristic composition, structure, and diversity of mangroves in the coastal areas of Mabini, Davao de Oro, Philippines. Biodiversitas 23: 4887-4893. Biodiversity and stand structure assessments of mangrove communities are important for their management and conservation. However, this aspect of mangrove ecology in the Davao Gulf is not yet fully explored, particularly in the coastal areas of Mabini, Davao de Oro, Philippines, despite being proclaimed as a protected area. Hence, this study assessed the species composition, structure and diversity of mangroves in the coastal areas of Mabini, Davao de Oro, Philippines. Using the belt transect method, 35 plots with 10 m x 10 m each were established and surveyed. Results revealed that the area is home to eight species belonging to six genera and five families. One vulnerable species, Avicennia rumphiana, was recorded on the study site. Of the identified species, Rhizophora apiculata was the most important species, with an importance value index of 144.41 %. Meanwhile, the surveyed mangrove communities had a mean diameter at breast height of 10.96 cm, a basal area of 27.93 m² ha?¹, and a mean density of 4192 stems ha?¹. Diversity analysis indicated that the sampled sites had low species biodiversity (H’ = 1.098), low species richness (R = 0.9601), and less even species distribution (J = 0.5280). These results add to the existing knowledge about mangrove communities in Davao Gulf. More importantly, they serve as important baseline information relevant to the management, protection, and conservation of mangroves within the Mabini Protected Landscape and Seascape.

The Mangrove Density, Diversity, and Environmental Factors as Important Variables to Support the Conservation Program of Essential Ecosystem Area in Muara Kali Ijo, Pantai Ayah, Kebumen

The planning of wetland essential ecosystem area (EEA) conservation and preservation activities is important to support ecosystem stability, including the mangrove ecosystem. These activities should consider the ecological, economic, and social aspects. This study aimed to analyze the indicator of the mangrove ecosystem to support the planning program of EEA conservation in Muara Kali Ijo, Pantai Ayah, Kebumen. The research method used the mapping and planning analysis of the EEA conservation program using the indicator of mangrove density, mangrove diversity, and environmental indicators. The results showed that mangrove density in Muara Kali Ijo was 1,500-4,300 trees/ha (moderate to very dense) and was dominated by Rhizophora mucronata and Rhizophora styllosa. The potential of total dissolved solids, water salinity, potential hydrogen, dissolved oxygen, biological oxygen demand, and nitrate had a good condition to support the mangrove’s life and growth. The ecosystem essential planning also had activity to conserve and preserve the Crocodylus porosus. The planning of ecosystem essential was developed in 18.5 ha, divided into five zones: mangrove preservation area of 5.90 ha, mangrove utilization area of 6.40 ha, mangrove arboretum of 4.40 ha, mangrove rehabilitation area of 1.30 ha, and specific utilization area of 0.5 ha. The wetland EEA in Muara Kali Ijo has important value in preserving the area from coastal disaster and increasing economic value with tourism and other activities. Keywords: Crocodylus porosus preservation, essential ecosystem conservation, mangrove zonation, Muara Kali Ijo, wetland conservation

Floristic Abundance and Diversity of Mangrove in Polluted Soil of Ikuru Town, Andoni, Rivers State, Nigeria

This study investigated into the floristic abundance and diversity of mangrove in polluted soils in Ikuru town, Andoni Local Government Area, Rivers State. The study covered an area of about five hectares (ha) of land. The area was measured using a transect of 100m x 20m in each zone. 10m transects were used in the experimental study. A control was chosen within the mangrove forest at Eagle Island Port Harcourt. Soil samples were randomly collected from subtidal, middle intertidal and lower intertidal zones, and control location using soil augar. Composite soil Samples were carefully placed into well labeled poly bags for laboratory analysis. Standard sampling procedures were adopted for soil physical and chemical analysis. Floristic species richness and diversity were also accessed. The results of the floristic compositions of the mangrove tree species in the hydrocarbon polluted soil of Ikuru Town showed that five (5) species, Avicenmia, Rhizophora mangle, Laguncularia racemosa, Acrostichum aureum, Rhizophora racemosa, four (4) families; namely Avicenmia, Avicenruocerae, Rhizophoraceae, Combitaceae and Pteridaceae. Furthermore, the results also showed that in polluted soil, Avicennia germinas recorded (35); unpolluted (52); Rhizophora mangle polluted (22); unpolluted (35); Lagunculania, racemosa polluted (20); unpolluted (30); Acrostichum aureum polluted (25); unpolluted (25); Rhizophora racemosa polluted (42) and unpolluted (60); Axonopus compresus polluted (15) unpolluted (20) and Cynodon dactylon polluted) (10) unpolluted (22) However, the diversity of the mangrove species in both polluted and contro soils were significantly different (P≤0.05), Avicennia gramina (35.52), Rhizophora mangle (22.35); Laguncularia racemosa (20.30), Acrostichum aureum (25.30) and Rhizophora recemosa (42.60). The results showed that the percentage abundance of the mangrove species differ in the percentage occurrence of the species found in the mangrove ecosystem, Rhizophora racemosa (24.88%, 25.49%) in both polluted and control soils, followed by Avicemmia Africana (20.71%; 21.3%) and the least abundant species was Laguncularia racemosa (11.82%; 12.30%). Therefore, rhizophora racemosa was highly recommended in a crude oil polluted sites and afforestation programmes in the mangrove

Floristic diversity, structure, and carbon stock of mangroves in a tropical lagoon ecosystem at Setiu, Malaysia

Abstract. Islam MA, Idris MH, Bhuiyan MKA, Ali MS, Abdullah MT, Kamal AHM. 2022. Floristic diversity, structure, and carbon stock of mangroves in a tropical lagoon ecosystem at Setiu, Malaysia. Biodiversitas 23: 3685-3697. Mangroves in lagoon habitats play an important role in ecosystem functions. Many studies on mangrove habitats are available in coastal habitats, however, the information on the lagoon ecosystems in tropical climates is scanty, especially regarding its vegetation and carbon storage. This study was carried out to assess the status of species diversity, composition, zonal structure and carbon storage of mangrove vegetation in Setiu lagoon, Malaysia. We used the transect line plots method in representative landward and small fringe island areas. The results showed that the floristic diversity of mangroves comprised 18 true mangroves and 11 associates, of which Avicennia rumphiana and Ceriops decandra were listed as threatened by IUCN. The stem density and basal area ranged from 1533 to 3800 individuals. ha-1 and 18.98-37.97 m2 ha-1, respectively. The mean tree diameter was 9.80 ± 2.85 cm, with a tree height of 10.35 ± 2.14 m. The mangrove species with the highest importance value index (IVI) was Rhizophora mucronata with 134.86, while the lowest was Acanthus ebracteatus with 13.23. The study revealed that small fringe islands in the lagoon were more diverse with biodiversity index values always higher than the landward zone. Total biomass from the dominant mangrove species was estimated at 522.9 t ha-1 with estimated carbon storage of 261.45 t ha-1 and sequestration potential of 959.54 t CO2 ha-1. Compared to the other mangrove ecosystems elsewhere, this study recommends that the Setiu lagoon is considered to be a healthy and newly generated mangrove forest. Therefore, proper monitoring is needed to ensure mangrove ecosystem health and functions.

Mangrove dispersal disrupted by projected changes in global seawater density

The degree to which the distribution of mangrove forests will be impacted by climate change depends on the dispersal and establishment of sea-faring propagules, which drive forest rejuvenation, gene flow and range expansion. Climate change affects sea surface density via changes in temperature and salinity. However, these changes have not been mapped and it remains unclear how these factors may impact mangrove propagule dispersal. Here, we provide evidence for strong warming of coastal mangrove waters and elevated geographic variability in surface ocean density under representative concentration pathway RCP 8.5 by 2100. The largest changes will occur in the Indo West Pacific region, the primary hotspot of mangrove diversity. By comparing propagule densities to predicted sea surface density, we assessed potential effects on mangrove propagule dispersal. In the future, a warmer and fresher ocean is likely to alter dispersal trajectories of mangrove propagules and increase rates of sinking in unsuitable offshore locations, potentially reducing the resilience of mangrove forests.

Species Diversity of Mangroves in Central Zambales, Philippines

The Philippines being an archipelagic country has one of the most diverse mangrove ecosystems. Species composition and diversity assessment are vital for sustainable management and conservation activities of mangrove resources. The diversity of mangroves was assessed to determine the status of the mangrove ecosystem in the central part of Zambales, Philippines. Data were gathered using a random quadrat sampling method in the twelve pre-selected stations. Each quadrat measures 1 meters and the quantitative description of each plant species was determined. There were a total of 15 mangrove species surveyed in the area, under seven families, which family Rhizophoraceae was the most represented, with six species, and families Euphorbiaceae, Meliaceae, and Myrsinaceae were only represented with one species each. Shannon’s Diversity Index showed that the mangrove ecosystems in Botolan had “very low” diversity (SDI=1.71) and Iba had “low” diversity (SDI=2.11). Anthropogenic sources such as agri-aqua and encroachment served as the major driving forces in the diversity of mangroves. Other threats include solid waste disposal, quarrying, oil spill, organic fertilizer run-off, and soil erosion among others. These may threaten species that could eventually cause greater biodiversity and economic loss. Hence, protection, conservation, and sustainable management be given priority.

Seafloor Terrain Shapes the Three-dimensional Nursery Value of Mangrove and Seagrass Habitats

Mangroves and seagrasses are important nurseries for many marine species, and this function is linked to the complexity and context of these habitats in coastal seascapes. It is also connected to bathymetric features that influence habitat availability, and the accessibility of refuge habitats, but the significance of terrain variation for nursery function is unknown. To test whether seafloor terrain influences nursery function, we surveyed fish assemblages from mangrove and seagrass habitats in 29 estuaries in eastern Australia with unbaited underwater cameras and quantified the surrounding three-dimensional terrain with a set of complementary surface metrics (that is, depth, aspect, curvature, slope, roughness) applied to sonar-derived bathymetric maps. Terrain metrics explained variability in assemblages in both mangroves and seagrasses, with differing effects for the entire fish assemblage and nursery species composition, and between habitats. Higher depth, plan curvature (concavity or convexity) and roughness (backscatter) were negatively correlated with abundance and diversity in mangroves and positively linked to abundance and diversity in seagrass. Mangrove nursery species (6 species) were most abundant in forests adjacent to flats with concave holes, rough substrates and low-moderate depths, whereas seagrass nursery species (3 species) were most abundant in meadows adjacent to deep channels with soft mounds and ledges. These findings indicate that seafloor terrain influences nursery function and demonstrate contrasting effects of terrain variation in mangroves and seagrass. We suggest that incorporating three-dimensional terrain into coastal conservation and restoration plans could help to improve outcomes for fisheries management, but contrasting strategies might be needed for different nursery habitats.

Implications of mangrove diversity on planted land area mangrove forest Pematang Kuala Serdang Bedagai

Pematang Kuala Village is one of the villages in the Mengkudu Bay District which has an area of almost 80% of which is mangrove forest. The existence of the Mangrove Forest is very important in addition to being a source of livelihood for the population, most of whom are fishermen, its function is also to protect coastal areas from increasingly severe coastal abrasion. The mangrove forest in this village is a mangrove forest that is managed jointly by the community to meet the needs of the community. Most of the village areas that are not mangrove forests are now converted into oil palm plantations or ponds which can damage mangrove ecosystems and coastal areas. This study aims to analyze the level of abundance, biomass, diversity and potential of fauna, distribution patterns of mangrove plants and fauna as well as the effect of conversion of mangrove diversity and the components contained therein on planted areas in the mangrove area to obtain data in Pematang Kuala Village, Teluk Mengkudu District, Serdang Be different. This research was conducted from January to March 2022. The study used data analysis techniques for diversity and abundance of the Shanon Winner index. There were 11 Mangrove species in total which were obtained at 3 research sites. Each research station is divided into 3 data collection, namely Trees, Trunks, and Seedlings. The highest diversity index was found in trees at station 1, which was 2.52%. and the lowest index is station 2 tree type was 0.15%.

Differential Adaptive Potential and Vulnerability to Climate-Driven Habitat Loss in Brazilian Mangroves

Geographic and environmental differences have been identified as factors influencing Brazilian mangrove trees' genetic diversity. Geographically, distinct species have convergent spatial genetic structures, indicating a limited gene flow between northern and southern populations. Environmentally, genomic studies and common garden experiments have found evidence of local adaptations along the latitudinal gradient of the Brazilian coast. However, little is known about how such adaptive heterogeneity could be affected by a rapidly changing climate in the coming decades, and the combination of deforestation and climate-induced habitat loss may affect these forests and their genetic diversity. Here, we applied two genomic-environmental association methods to model the turnover of potentially adaptive alleles for two dominant mangrove trees: Avicennia germinans and A. schaueriana. We analyzed a total of 134 individuals from six populations of A. germinans and 10 populations of A. schaueriana spanning the Brazilian coast from 1 °S to 28 °S. Gradient forest models identified temperature-related variables as the most important predictors for A. germinans outlier loci, whereas both temperature and precipitation were important for A. schaueriana. We modeled allele frequencies and projected them for future climatic scenarios to estimate adaptively driven vulnerability. We assessed climate-driven habitat loss through climate-only distribution models and calculated annual deforestation rates for each sampled region. Finally, to assess the vulnerability of individual populations, we combined the environmental suitability, deforestation data, and adaptive vulnerability projections. For both species, subtropical populations presented a higher vulnerability than equatorial populations to climate-driven habitat loss. We also identified deforestation rates at the sampled sites that were alarmingly higher than the global average mangrove deforestation rate. Our results provide improved estimates of the impacts of ongoing climate change and human-caused habitat loss on the distribution of mangroves and highlight the importance of site-based conservation strategies that consider individual subtropical and equatorial mangrove forests.

Diversity and Vertical Distribution of Sedimentary Bacterial Communities and Its Association with Metal Bioavailability in Three Distinct Mangrove Reserves of South China

The structure of sedimentary bacterial communities in mangroves depends on environmental factors such as pH, salinity, organic matter content, and metal pollution. To investigate the effect of heavy metal pollution on such communities, core samples of sediments from four sites in three distinct mangrove reserves (Golden Bay Mangrove Reserve in Beihai, Guangxi province (GXJHW), Shankou Mangrove Reserve in Hepu, Guangxi province (GXSK), and MaiPo mangrove in Hong Kong (MPCT and MPFQ)) in South China were analyzed for physicochemical properties, multiple chemical forms of metals, and vertical bacterial diversity. Sedimentary bacterial communities varied greatly among the different sampling sites, with biodiversity decreasing in the order of GXSK, GXJHW, MPFQ, and MPCT. Proteobacteria was the dominant phylum, followed by Chloroflexi, across all four sampling sites. Multivariate statistical analysis of the effect of environmental factors on the sedimentary bacterial communities found that total carbon was the only physicochemical factor with a significant influence at all four sites. The correlations between environmental factors and bacterial structure were weak for the two sites in Guangxi province, but strong at MPCT in Hong Kong where environmental factors were almost all significantly negatively correlated with bacterial diversity. Variance partitioning analysis revealed that physicochemical properties and chemical forms of metals could explain most of the changes in bacterial diversity. Overall, we observed that heavy metal forms were more important than total metal content in influencing the sedimentary bacterial diversity in mangroves, consistent with the more bioavailable metal species having the greatest effect.

An Overview of Vertebrate Faunal Diversity in Sri Lankan Mangroves

Fernando, E.; Wickramasinghe, D., and Fernando, V.K., 2022. An overview of vertebrate faunal diversity in Sri Lankan mangroves. Journal of Coastal Research, 38(2), 429–448. Coconut Creek (Florida), ISSN 0749-0208. Sri Lanka is rich in floral and faunal communities. The mangrove forests found within the island are particularly important, being crucial habitats for endemic and globally threatened vertebrates. However, a comprehensive overview of the island's vertebrates known to utilise mangrove habitats has not yet been studied. This review uses available publications to categorise Sri Lankan vertebrates inhabiting mangroves according to the five vertebrate groups: ichthyofauna, amphibians, reptiles, avifauna, and mammals; 440 different species were subsequently categorised. A number of caveats have been addressed, and this review has given improved insight into the scale of diversity the island's mangrove habitats hold. This study will form the baseline for further mangrove vertebrate research, particularly in species groups where quantitative evidence and conservation statuses currently lacks.

Keanekaragaman Jenis Mangrove Pada Tahura Ngurah Rai Sekitar PLTD/G Pesanggaran

Mangrove forest as a tropical coastal vegetation community is dominated by several species of mangrove trees that are able to grow and develop in muddy coastal tidal areas. This ecosystem has ecological and economic functions. Indonesia has the highest mangrove area, which is 3,112,989 ha or 22.6% of the world's total mangrove area. The majority of mangrove forests in Bali Province grow in the Ngurah Rai Taman Hutan Raya (TAHURA). This study aims to determine the condition and diversity of mangroves in The Ngurah Rai Tahura which borders the PLTD/G PT Indonesia Power UBPB Pesanggaran Denpasar. Types of Mangroves found in The Ngurah Rai Tahura Around PLTD/G Pesanggaran totaled 18 species, dominated by 6 species of mangrove with high importance (INP > 20%) respectively: Rhyzophora apiculata INP = 63.221%, Rhyzophora mucronata INP = 52.433%, Sonneratia alba INP = 30.323%, Sonneratia caseolaris INP = 28.670%, Xylocarpus granatum INP = 25.320 %, and Bruguiera gymnorrhyza INP = 22.421%. The results of the analysis of the Important Value Index as a whole are 298.342. This indicates that the mangrove community at the research site is quite stable, dense and stable, while the diversity index is 1.9546.

Genetic Diversity and Mating System of Two Mangrove Species (Rhizophora apiculata and Avicennia marina) in a Heavily Disturbed Area of China

Mangrove forests are distributed in the intertidal zones of tropical and subtropical regions, and have been severely damaged by anthropogenic activities, climate change, and stochastic events. Although much progress has been made in the conservation and restoration of mangroves in China, studies of the genetic diversity of mangroves are lacking, especially for isolated populations, yet such studies are essential for guiding conservation and restoration efforts. Here, we evaluated the genetic diversity, spatial genetic structure, and mating system of two mangrove species, Rhizophora apiculata and Avicennia marina, in a heavily disturbed area in Tielu Harbor, Sanya City, Hainan Island, China, using 18 nuclear microsatellite markers. We found that the genetic diversity of R. apiculata, which is classified as ‘Vulnerable’ in the China Red List categories, was high and similar compared with the genetic diversity estimates of other populations reported in previous studies. In contrast, the genetic diversity of A. marina, which is classified as a species of ‘Least Concern’, was low compared with the genetic diversity estimates of other populations. We then evaluated the presence of genetic bottlenecks, spatial genetic structure, and the mating system to determine the effects that habitat destruction has had on these two species. Our findings indicate that distinct conservation and restoration approaches are needed for these two species. Generally, our results provide valuable information that will aid the development of conservation and restoration strategies for the mangroves of Tielu Harbor.

Mangrove diversity is more than fringe deep

Mangroves form coastal tropical forests in the intertidal zone and are an important component of shoreline protection. In comparison to other tropical forests, mangrove stands are thought to have relatively low genetic diversity with population genetic structure gradually increasing with distance along a coastline. We conducted genetic analyses of mangrove forests across a range of spatial scales; within a 400 m2 parcel comprising 181 Rhizophora mangle (red mangrove) trees, and across four sites ranging from 6–115 km apart in Honduras. In total, we successfully genotyped 269 R. mangle trees, using a panel of 677 SNPs developed with 2b-RAD methodology. Within the 400 m2 parcel, we found two distinct clusters with high levels of genetic differentiation (FST = 0.355), corresponding to trees primarily located on the seaward fringe and trees growing deeper into the forest. In contrast, there was limited genetic differentiation (FST = 0.027–0.105) across the sites at a larger scale, which had been predominantly sampled along the seaward fringe. Within the 400 m2 parcel, the cluster closest to the seaward fringe exhibited low genetic differentiation (FST = 0.014–0.043) with the other Honduran sites, but the cluster further into the forest was highly differentiated from them (FST = 0.326–0.414). These findings contradict the perception that genetic structure within mangroves forests occurs mainly along a coastline and highlights that there is greater genetic structure at fine spatial scales.

Effectiveness of community-based mangrove management for biodiversity conservation: A case study from Central Java, Indonesia

Efforts to rehabilitate degraded mangrove ecosystems in Indonesia started in the 1960s and have recently received increased attention. Rehabilitation efforts have been mainly conducted through community-based mangrove management (CBMM) programs, aimed at restoring important services such as food provisioning and coastal protection, and for biodiversity conservation. Our study assessed the effectiveness of CBMM strategies to conserve biodiversity in four adjacent Indonesian coastal villages (Sriwulan, Bedono, Timbulsloko, Surodadi) in Central Java. For this, we used complementary methodologies combining participatory resource mapping, semi-structured interviews, questionnaire-based interviews, field assessments and literature review. This yielded detailed information on mangrove rehabilitation activities, management approaches and the impacts of mangrove rehabilitation on biodiversity in the four villages. Our analysis focussed on mangrove forest structure and diversity and macro invertebrate diversity.The overall comparison of management performance shows a higher achievement of CBMM applied in Bedono in terms of a larger mangrove diversity and net reforestation coverage, also supporting a higher macrobenthic faunal diversity compared to the other villages. The main contributing factors were a) the longer-term funding and maintenance, b) the greater acceptance for protective legislation, c) the higher levels of public support, d) the fact that more species of mangroves were used, e) the much larger spatial scale of mangrove restoration, and f) the presence of additional measures to reduce wave action in highly eroded areas. The results revealed key determinants of success when restoring mangroves for the purpose of biodiversity conservation and the influence of different CBMM approaches.

Analysis of the diversity and evenness of mangrove ecosystems in the Pacitan Coast, East Java, Indonesia

Abstract. Sholiqin M, Pramadaningtyas PS, Solikah I, Febriyanti S, Pambudi MD, Mahartika SB, Umam AF, Liza N, Setyawan AD. 2021. Analysis of the diversity and evenness of mangrove ecosystems in the Pacitan Coast, East Java, Indonesia. Intl J Bonorowo Wetlands 11: 84-94. Indonesia has a high mangrove diversity with 43 species of true mangrove plants. Mangrove grows along the coastline of Indonesia’s islands, one of which is situated on the southern coast of Java. Pacitan, which belongs to the south coast of East Java and has 70,709 km of coastline, is an area with the potential to have a diverse of mangrove vegetation. The existence of mangroves plays a role in carbon sequestration and the stability of coastal ecosystems. The aim of this study was to determine the mangrove diversity and evenness index in the southern coast of Pacitan. This research was conducted on November 2021 in three locations, namely the Teleng Ria, Grindulu Estuary, and Siwil Beach. Data was collected using a plot of 10 x 10 m2 for trees, 5 x 5 m2 for saplings, and 2 x 2 m2 for seedlings. The data obtained were analyzed using the Shannon Wiener and Evenness index to calculate the mangrove diversity and evenness value. There are 8 species of mangroves (7 species of major and 1 species of minor mangrove), and 2 species of associated mangroves, with the domination of Rhizophora stylosa. The Shannon Weiner diversity index shows that the mangrove diversity index in the research areas ranges from low to moderate. The Evenness Index presents that Teleng Ria Estuary possesses a high evenness value, indicating its stable mangrove condition.

Mangrove ecology and species distribution along the Gorai Creek of Mumbai coast, Maharashtra, India

The extensive mangrove forest of Gorai Creek, Mumbai coast, has recently seen substantial deterioration. The results of a study on mangrove diversity conducted in Gorai Creek on the Mumbai coast from June 2017 to May 2018 are presented here. During the course of the study, twelve species of mangroves from five families and eight genera were identified in each of the three study locations along the creek. Avicennia marina accounted for 13.44% of the Gorai creek marshes, confirming its predominance. Sonneratia alba, Avicennia officinalis, Rhizophora apiculata, Bruguiera cylindrica, Kandelia candel, and Acanthus ilicifolius are among the mangrove species found in the estuarine embayment, with other species strewn around. A diverse range of species, including endangered migratory birds and herpetofauna, can be found in these mangrove environments. Mangroves have been observed to have narrowed in density with time, and it is critical to begin conservation efforts as speedily as humanly possible.

Effects of shrimp pond effluent on functional traits and functional diversity of mangroves in Zhangjiang Estuary

In recent years, the scale of shrimp ponds has rapidly increased adjacent to mangrove forests. Discharge of shrimp pond effluent has led to degradation of the surrounding environment and reduction of biodiversity in the estuary. But it remains poorly understood how shrimp pond effluent affects functional traits and functional diversity of mangroves. We sampled roots, stems and leaves of Kandelia obovata and other mangrove plants, as well as sediments and pore water from shrimp pond effluent polluted area (P) and clean area (control area, C) in Zhangjiang Estuary in southeast coast of China. Twenty plant functional traits and six functional diversity indices were analyzed to explore the effects of shrimp pond effluent on individual plants and mangrove communities. The results showed that the discharge of shrimp pond effluent significantly affected the nutrient content in soils and pore water, for example, sediment NH4+ and NO3− concentration increased from 0.26 ± 0.06 to 0.77 ± 0.29 mg/g and from 0.05 ± 0.03 to 0.16 ± 0.05 mg/g, respectively, when comparing the C and P site. Furthermore, some mangrove plant functional traits such as plant height, diameter at breast height, canopy thickness and specific leaf area were significantly increased by the effluent discharge. Functional diversity in the polluted area reduced as a whole compared to the control area. In particular, ammonium and nitrate nitrogen input is the main reason to induce the changes of plant functional traits and functional diversity. Besides, the community structure changed from functional differentiation to functional convergence after shrimp pond effluent discharge. In addition, the long-term shrimp pond effluent discharge may lead to the ecological strategy shift of K. obovata, while different organs may adopt different ways of nutrient uptake and growth strategies in the face of effluent disturbance. In conclusion, pollution from shrimp pond does affect the functional traits of mangrove plants and functional diversity of mangrove community. These results provide strong evidence to assess the impact of effluent discharges on mangrove plants and provide theoretical basis for conservation and sustainable development of mangroves.

Optimizing mangrove conservation efforts with improved understanding of phytosociology-ecology synergy in Sri Lanka

The study aimed to understand the forest structure and ecological factors influencing mangrove distribution in eight mangrove forests across three climatic zones in Sri Lanka. We studied mangrove diversity and vegetation structure with 10m wide belt transects laid of different lengths (n=96) across the land-water gradient. Mangroves along the transect were identified, enumerated, and measured diameter at breast height (DBH). Subsurface water samples were taken in the adjoining lagoon/estuary to assess the environmental parameters (n=144), and water quality parameters were measured. Site-dependent spatial changes in the community structure were depicted through cluster analysis (CA). The forest survey revealed a heterogeneous mixture of 20 true mangrove species across the sites dominated by Avicennia, Rhizophora, and Sonneratia spp. Among the several environmental parameters analyzed by the distance-based redundancy ordination analysis (dbRDA), salinity, dissolved oxygen, and precipitation were found to be controlling factors in mangrove community structure. In addition, discriminant analysis confirmed the presence of ecological-phytosociological influence on mangrove assemblages identified through CA. The significant structural parameters tree density, and taxonomic diversity when tested using the canonical analysis of principal coordinates (CAP), altered the species abundance across the sites surveyed. The results suggest that there is a strong linkage between phytosociology and ecology with the mangrove forest distribution and this relationship needs to be considered wisely to fortify successful restoration practices.