Matang Mangrove Forest Reserve Research Articles

Assessing the Productivity of the Matang Mangrove Forest Reserve: Review of One of the Best-Managed Mangrove Forests

Mangrove ecosystems are crucial for biodiversity and coastal protection but face threats from climate change and human activities. This review assesses the productivity of the Matang Mangrove Forest Reserve (MMFR) in Malaysia, which is recognised as one of the best-managed mangrove forests, while also addressing challenges such as deforestation and climate change-induced factors. This review explores the concept of productivity in mangrove forests, highlighting their role in carbon sequestration and discussing litterfall measurements as fundamental metrics for assessing primary productivity. An analysis of historical changes in MMFR’s biomass and productivity revealed fluctuations influenced by logging, reforestation, and climatic conditions. Trends in MMFR productivity indicate a concerning decline attributed to anthropogenic activities such as aquaculture and industrial projects. A regression analysis conducted on Rhizophora apiculata data with age as the predictor and AGB as the response variable indicated a positive trend (slope = 3.61, R-squared = 0.686), suggesting a quantitative increase in AGB with age. Further analysis revealed a significant negative trend in MMFR’s overall productivity over years (coefficient = −3.974, p < 0.05) with a strong inverse relationship (rho = −0.818, p < 0.05), indicating declining AGB trends. Despite these challenges, this review underscores the significance of sustainable management practices, effective conservation efforts, and community engagement in maintaining mangrove ecosystem health and productivity. In conclusion, sharing management lessons from MMFR can contribute to global conservation and sustainable mangrove forest management efforts, fostering resilience in these vital ecosystems.

Historical ecological monitoring and appraisal for extractive uses and other values in Malaysia unveils consequences of regime shifts in 120 years of mangrove management

Matang Mangrove Forest Reserve (MMFR) in Peninsular Malaysia, with its ‘management plans’ traced back to 1904, is the longest-managed mangrove forest for timber (pole/charcoal) production through intermediate thinning and final felling (or clear-felling) operations. For 115 years, the mangroves in the productive zones have been harvested under a 30-year rotation cycle. The 10-year management plans released by the Forestry Department have been supporting silvicultural management. Despite the long management history, the mangrove biomass and quality were found to have decreased in recent years. Therefore, we analyzed all the available management plans between 1904 and 2019 to summarize both qualitative and quantitative data (i.e., silviculture policy/practice and trading) in search of the shifts in management practices. A comparison with relevant literature on the MMFR was also made to evaluate the potential issues of scientific concern in the ongoing management. We found that the higher yield (per ha) of charcoal and poles in the past 20 years resulted from exploiting the restrictive productive zones (=forest that is environmentally sensitive and marginally productive). With a policy inclined greatly toward the financial outcomes of timber-based products, the current silviculture practice may turn out to be unsustainable if any impacts like extreme weather, tree dieoff, sea-level rise, etc., affect mangroves in the future. We discuss the dilemma between greenwood harvesting and the protection of a diverse range of ecosystem service. This study sheds light on the strengths and weaknesses of historic and current mangrove timber harvesting regimes in MMFR and can contribute to supporting future sustainable mangrove management in Matang, and other forest formation.

Mangrove Dynamics Evaluation at Matang Mangrove Forest Reserved by Multi-temporal Satellite Imageries

Mangrove ecosystems support a wide range of terrestrial and marine organisms by offering sustenance, reproductive habitats, and nurturing environments. The Matang Mangrove Forest Reserve (MMFR), spanning over 40,000 ha, poses challenges in effectively managing and evaluating the entire area. Hence, remote sensing techniques are employed to effectively monitor and map the temporal fluctuations of land use and land cover occurring within mangrove forest areas. In this study, dynamics over nine (9) years (2011to 2020) of the mangrove ecosystem were evaluated using RapidEye 2011 and Landsat 8 (OLI) 2020 satellite imageries. Change detection was implemented using pixel-by-pixel modelling analysis. The present study revealed the conversion of mangrove area to waterbody at 4625.1 ha (16.7%), dryland forest at 1886.1 ha (6.8%), and oil palm plantations at 186.9 ha (0.7%). The area conversion was attributed to erosion, logging operations, the establishment of aquaculture facilities, and agricultural practices. Hence,the acquisition of data pertaining to the present condition of mangrove forest species, as well as the temporal fluctuations in the study area, holds significant importance for all stakeholders involved in the preservation of this ecosystem.

Elemental Composition of Above and Belowground Mangrove Tissue and Sediment in Managed and Unmanaged Compartments of the Matang Mangrove Forest Reserve.

Mangrove productivity depends on the storage of nutrients and elements. Elemental concentrations were examined in leaves, roots, and sediments for three age stands (15, 25 years, and VJR) of Rhizophora apiculata in the Matang Mangrove Forest Reserve (MMFR). Six compartments with two compartments each for each age group were used to analyze sixteen elements. Four types of elemental patterns were examined with decreasing order during analysis: (1) Cd < Cu < Pb < Zn < Mg < Mn < Fe < K < Na < Ca and P% < S% < N% < C% in leaves, (2) Cd < Pb < Cu < Zn < Mg < Mn < Fe < K < Na < Ca and P% < S% < N% < C% in roots, (3) Cd < Pb < Cu < Zn < Mg < Mn < K < Fe < Na < Ca and P% < N% < S% < C% in sediment samples and (4) Cd(S) < Pb(S) < Cu(S) < Zn(S) < Mg(S) < Mn(L) < K(L) < Fe(S) < Na(R) < Ca(R) and P%(S) < S%(S) < N%(L) < C%(R) collectively for all samples. Evidence that elements do not store primarily in above-ground biomass can be found in the observation that elements are stored more in sediment and roots. The outcome of the present study shows that the rate of increase of elements in trees (leaves and roots) was less as compared to sediments, where the elemental concentration increased considerably with time. Elemental concentration comparison within three age classes showed that C, N, and S were significantly different in all three types of samples. The δ15N ratios showed positive values in all six compartments which supported the concept that the δ15N ratio could not be observed in N concentration in this study. The δ13C values showed more negative values in all six compartments which represented less salinity and a freshwater intake. The S, P, and heavy metals concentrations were high. The concentrations of Cd, P, N, C, and S in the sediment influenced variations in four compartments in accordance with the three mangrove age groups. The results of this study can be utilized to create management plans for MMFR and conduct risk assessments of the elements' concentration in sediment.

Geostatistical Analysis of Mangrove Ecosystem Health: Mapping and Modelling of Sampling Uncertainty Using Kriging

This study assessed the health of the mangrove ecosystem and mapped the spatial variation in selected variables sampled across the Matang Mangrove Forest Reserve (MMFR) by using a geostatistical technique. A total of 556 samples were collected from 56 sampling points representing mangrove biotic and abiotic variables. All variables were used to generate the semivariogram model. The predicted variables over the entire MMFR have an overall prediction accuracy of 85.16% (AGB), 90.78% (crab abundance), 97.3% (soil C), 99.91% (soil N), 89.23% (number of phytoplankton species), 95.62% (number of diatom species), 99.36% (DO), and 87.33% (turbidity). Via linear weight combination, the prediction map shows that mangrove ecosystem health in Kuala Trong throughout the Sungai Kerang is excellent (5: MQI > 1.5). Some landward areas of Kuala Trong were predicted to have moderate health (3: −0.5 ≤ MQI ≤ 0.5), while Kuala Sepetang was predicted to have the bad ecosystem health (2: −1.5 ≤ MQI ≤ −0.5), with active timber harvesting operations and anthropogenic activities in the landward areas. The results of this method can be utilised to carry out the preferred restoration, through appropriate management and facilities distribution, for improving the ecosystem health of mangroves.

The role of microzooplankton grazing in the microbial food web of a tropical mangrove estuary

In the Matang Mangrove Forest Reserve (MMFR), the role of microzooplankton (20–200 μm) grazing on phytoplankton as a channel for carbon transfer to higher trophic levels was investigated. Our results showed that primary production was higher during the southwest monsoon (SWM) (1905 ± 1478 μgCl−1d−1) than in the northeast monsoon (NEM) (708 ± 474 μgCl−1d−1). Microzooplankton grazing was tightly coupled to primary production in both SWM and NEM, accounting for 97% and 68% of primary production, respectively. Both primary production (activation energy: 1.29 ± 0.54 eV) and microzooplankton grazing (2.05 ± 0.63 eV) showed temperature dependency, and revealed a shift towards heterotrophy with seawater warming, specifically at temperatures above 32 °C. As a conclusion, the microbial food web in MMFR is characterised by high primary production that was efficiently grazed by microzooplankton.

Trophic guild structure and dietary patterns of a juvenile-dominated demersal fish community in a tropical mangrove estuarine system

Community-wide understanding of food web dynamics in species-rich tropical estuaries are generally lacking, exacerbating the challenges of managing these valuable coastal habitats. To address this gap, trophic guilds and dietary patterns were elucidated for 39 species of a juvenile-dominated demersal estuarine fish community in the Matang Mangrove Forest Reserve, an Important Marine Mammal Area. Fishes were sampled monthly for a year using otter trawl, and stomach contents were analyzed. Of the seven trophic guilds identified from clustering analysis, the three most speciose ones were shrimp feeders (12 species), zooplanktivores (9), and generalist crustacivores (7). Copepods occurred in diets of 50% of all fish species and were the most important food item volumetrically for specialist zooplanktivores. Diverse shrimp and prawn taxa, including commercially valuable Acetes and juvenile penaeids, showed highest frequency of occurrence in stomachs and supported the shrimp feeder and crustacivore guilds that contained relatively more diet generalists. Biomass-dominant annelidivore guild members are known to be a vital food resource for highly threatened coastal cetaceans. Ontogenetic diet shift, wide intra-guild diet breadth, seasonality in major resource use, and prevalence of detritus in diet were feeding strategies that reduced niche overlap and competition among fish species sharing common food resources. Future fisheries management must consider the bottom-up trophic impacts from excessive removal of valuable prey resources such as shrimps on equally valuable fish consumers that depend on them.

Can Mangrove Silviculture Be Carbon Neutral?

Matang Mangrove Forest Reserve (MMFR) in peninsular Malaysia has been managed for pole and charcoal production from Rhizophora stands with a 30-year rotation cycle since 1902. The aim of this study is to estimate the carbon budget of the MMFR by considering the carbon stock of the forest, evaluated from remote sensing data (Landsat TM and ETM+, JERS-1 SAR, ALOS PALSAR, ALOS-2 PALSAR-2, SRTM, TANDEM-X, and WorldView-2) for aboveground carbon and field data for belowground carbon. This was investigated in combination with the emissions from the silvicultural activities in the production chain, plus the distribution and consumer-related activities covering the supply chain, estimated with appropriate emission factors. The aboveground biomass carbon stock of the productive forest was of 1.4 TgC, while for the protective forest (not used for silviculture) it was at least equal to 1.2 TgC. The total soil carbon of ca. 32 TgC shows the potential of the MMFR as a carbon sink. However, the commercial exploitation of mangroves also generates greenhouse gasses with an estimate of nearly 152.80 Mg C ha−1 during charcoal production and up to 0.53 Mg C ha−1 during pole production, for a total emission of 1.8 TgC. Consequently, if the productive forest alone is considered, then the carbon budget is negative, and the ongoing silvicultural management seems to be an unsustainable practice that needs a reduction in the exploited area of at least 20% to achieve carbon neutrality. However, even with the current management, and considering the protective forest together with the productive zones, the MMFR carbon budget is slightly positive, thus showing the importance of mangrove conservation as part of the management for the preservation of the carbon stock.

Assessment of Mangrove Sediment Quality Parameters from Different Seasons, Zones and Sediment Depths

Heavy metal concentrations have risen throughout Malaysia's coastline because of industrial wastewater discharge, affecting mangrove ecology significantly. Lead (Pb), Zinc (Zn), Chromium (Cr), and Nickel (Ni) were used to establish the Mangrove Sediment Quality Index (MSQi), which assesses and monitors the quality of mangrove sediment. This study was conducted at Matang Mangrove Forest Reserve (MFFR) in Perak, Malaysia to examine changes in MSQi features across seasons, mangrove zones, and sediment depths at three separate MMFR locations. Sediment samples were taken using auger in two different seasons (dry and wet seasons). After the silt was removed using aqua regia techniques, heavy metals were examined using an Atomic Absorption Spectrophotometer. According to MSQi criteria in various seasons at three different locations, the highest concentration of heavy metals (HMs) was detected in the dry season in the least disturbed region at three different locations. During dry seasons, only Cr and Ni levels are higher in moderately and highly disturbed areas. Pb and Zn levels in moderately and highly disturbed areas are higher than in least disturbed areas during the rainy season. MSQi parameters in different mangrove zones at three locations showed that most HMs content is highest in the landward zone and it can be concluded that HMs sources are anthropogenic. Furthermore, MSQi measurements at three locations revealed that heavy metals content is highest at 015 cm and lowest at other depths.

Mangroves Fueling Livelihoods: A Socio-Economic Stakeholder Analysis of the Charcoal and Pole Production Systems in the World’s Longest Managed Mangrove Forest

The declining mangrove cover worldwide highlights the necessity of understanding the linkages between ecological and socio-economic dimensions of mangrove management. This study analyses the socio-economic aspects of the pole and charcoal production systems at Matang Mangrove Forest Reserve (MMFR), known as the world’s longest managed mangrove forest, in Malaysia. We performed a socio-economic survey to identify the roles and relationships among stakeholders in the pole/charcoal production system and quantified the cash-flows in monetary value. Altogether, 160 interviews were conducted with contractors, forest officials, workers, middle-men, and consumers. The contractors are functioning as a “hub” from production to commercialization and receive major economic benefits. The commercialization of most charcoal (>80%) aims to its exportation to Japan while the commercialization of poles is local. Although the workers’ income was less than the minimum wage, they still prefer charcoal production jobs because of the availability and geographic proximity of these jobs. Our research suggests a standard salary and health insurance schemes for the workers to reduce social inequality/poverty and improve their well-being. Considering that mangroves occur in over 120 countries, our methodology can be used as a reference to unveil the socio-economic situation of mangrove-dependent communities as well as to map the economic cash-flow of the local activities that form the basis for long-term sustainable mangrove management plans.

Development of Mangrove Sediment Quality Index in Matang Mangrove Forest Reserve, Malaysia: A Synergetic Approach

Sediment is an important part of heavy metal cycling in the coastal ecosystem, acting as a potential sink and source of inorganic and organic contaminants as environmental conditions change. The productivity of mangroves is utterly dependent on sediment enrichment. Moreover, mangrove sediment can trap pollutants discharged by households, industries, and agriculture activities. In this regard, it is essential to assess sediment quality in the presence–absence of heavy metals that are toxic to most living organisms. Thus, the question of how sediment quality is used as an index in the mangrove domain has arisen. Due to the many complex characteristics such as seasonal zones, tidal patterns, flora and fauna, and water, no specific method is used in Malaysia for assessing and monitoring mangrove sediment quality. Thus, the current study intended to develop a mangrove sediment quality index (MSQi) in the Matang mangrove forest in Perak, Malaysia. An area was selected based on the distinct level of mangrove disturbances. At 1.5 m depth, sediments were sampled in five segments (0–15, 15–30, 30–50, 50–100, and 100–150 cm). All the sediment physicochemical properties were then analysed. Fourteen variables were chosen and included in MSQi. This index categorises mangrove sediment levels as I = Very Bad, II = Bad, III = Moderate, IV = Good, and V = Excellent. MSQi will be used as a guideline in monitoring mangrove sediment pollution. In conclusion, the data analysis showed that the Sepetang River (SR) was highly disturbed, followed by the Tinggi River (TR) (moderately disturbed), and the Tiram Laut River (TLR) (least disturbed).

Spectral signature analysis to determine mangrove species delineation structured by anthropogenic effects

In this study, we used the spectral information divergence (SID) and spectral angle mapper (SAM) algorithm classification to identify ~ 40,000 individual trees from 19 mangrove species; these data were collected from 7 sampling points spread across 40,288 ha of the Matang Mangrove Forest Reserve (MMFR) in the state of Perak, Malaysia. This information was examined and analysed to answer two questions: (1) can medium resolution of satellite image identify the individual mangrove species (2) how are the distributions of individual species within the mangrove zonation associated with the anthropogenic matrix? Species identification with spectral library derived from the in-situ measurements using the SID algorithm was compared with that derived from the Landsat 8 using the SAM algorithm; it was found that the two methods offered different but complementary information with different rates of accuracy. The observed levels of classification accuracy are at 84.95% and 85.21%, respectively for SID and SAM algorithm classification. The mangrove species distribution has a correlation with the anthropogenic activities, but the distribution occurred randomly without specific zones. All the 19 selected mangrove species are closely related with different correlation by the anthropogenic activities. The use of the SID and SAM algorithms may provide the most promising way of classification for improving the mangrove species identification, with medium resolution of satellite image. Recognising the characteristics of mangrove zonation may give a better understanding of mangrove species appearances and conservation. However, mangrove zonation will remain a daunting mapping task and is a challenge for the ecologists in the future.

Plant species- and stage-specific differences in microbial decay of mangrove leaf litter: the older the better?

Leaf litter and its breakdown products represent an important input of organic matter and nutrients to mangrove sediments and adjacent coastal ecosystems. It is commonly assumed that old-grown stands with mature trees contribute more to the permanent sediment organic matter pool than younger stands. However, neither are interspecific differences in leaf decay rates taken into account in this assumption nor is our understanding of the underlying mechanisms or drivers of differences in leaf chemistry sufficient. This study examines the influence of different plant species and ontogenetic stage on the microbial decay of mangrove leaf litter. A litterbag experiment was conducted in the Matang Mangrove Forest Reserve, Malaysia, to monitor leaf litter mass loss, and changes in leaf litter chemistry and microbial enzyme activity. Four mangrove species of different morphologies were selected, namely the trees Rhizophora apiculata and Bruguiera parviflora, the fern Acrostichum aureum and the shrub Acanthus ilicifolius. Decay rates of mangrove leaf litter decreased from A. ilicifolius to R. apiculata to B. parviflora to A. aureum. Leaf litter mass, total phenolic content, protein precipitation capacity and phenol oxidase activity were found to decline rapidly during the early stage of decay. Leaf litter from immature plants differed from that of mature plants in total phenolic content, phenolic signature, protein precipitating capacity and protease activity. For R. apiculata, but not of the other species, leaf litter from immature plants decayed faster than the litter of mature plants. The findings of this study advance our understanding of the organic matter dynamics in mangrove stands of different compositions and ages and will, thus, prove useful in mangrove forest management.

Growth and Reproductive Status of the Spotted Scat <i>Scatophagus argus</i> in Mangrove Estuary in Matang Mangrove Forest Reserve, Malaysia

Growth and Reproductive Status of the Spotted Scat <i>Scatophagus argus</i> in Mangrove Estuary in Matang Mangrove Forest Reserve, Malaysia

Shifts in Diatom Dominance Associated with Seasonal Changes in an Estuarine-Mangrove Phytoplankton Community

A study on seasonal phytoplankton abundance and composition in a mangrove estuary, Matang Mangrove Forest Reserve (MMFR), Malaysia, was carried out to determine the phytoplankton structure in this ecosystem, and to identify potential indicators of environmental changes. Phytoplankton samples were collected bimonthly from June 2010 to April 2011, to cover both dry (June to October) and wet (November to April) seasons, at four selected sampling sites along the river. Diatoms showed the highest number of species (50 species) from a total of 85 phytoplankton species from 76 genera. Diatoms contributed more than 90% of the total phytoplankton abundance during the dry season (southwest monsoon) and less than 70% during the wet season (northeast monsoon) as dinoflagellates became more abundant during the rainy season. Two diatoms were recorded as dominant species throughout the sampling period; Cyclotella sp. and Skeletonema costatum. Cyclotella sp. formed the most abundant species (62% of total phytoplankton) during the dry period characterized by low nutrients and relatively low turbidity. Skeletonema costatum contributed 93% of the total phytoplankton in October, which marked the end of the dry season and the beginning of the wet season, characterized by strong winds and high waves leading to the upwelling of the water column. Massive blooms of Skeletonema costatum occurred during the upwelling when total nitrogen (TN) and total phosphorus (TP) concentrations were highest (p < 0.05) throughout the year. The abundance of diatom species during the wet season was more evenly distributed, with most diatom species contributing less than 12% of the total phytoplankton. Autotrophic producers such as diatoms were limited by high turbidity during the northeast monsoon when the rainfall was high. During the wet season, Cyclotella and Skeletonema costatum only contributed 9% and 5% of the total phytoplankton, respectively, as dinoflagellates had more competitive advantage in turbid waters. This study illustrates that some diatom species such as Cyclotella sp. and Skeletonema costatum could be used as indicators of the environmental changes in marine waters.

Development of landscape forest performance index to assess forest quality of managed forests

Besides timber and economic benefits, forest ecosystems provide other ecosystem services related to biological diversity and environmental functions of forests. Assessing some of the ecosystem services, which can be an indicator of forest quality at a landscape level requires the use of geospatial technology to achieve it. The aim of this work is to develop a forest performance index at the landscape level for mangrove forests. Several ecosystem services were identified and selected as indicators. The target value was set for each indicator and calculated into percentage value, which indicates progression to the target value, combined from field and geospatial data. The forest performance index was then produced by combining all indicators to get an overall performance of one particular forest area with respect to the target. The index was developed and tested at one of the best managed mangrove forests in the world, which is Matang Mangrove Forest Reserve (MMFR) in Perak. Based on the index that has been developed, the forest quality of MMFR, which consists of 19 forest reserves, is classified as good forest with an overall score of 72 percent. Pulau Kecil and Telok Kertang forest reserves have shown a very good forest quality with an overall score over 80 percent. Other 17 forest reserves in MMFR shown good forest quality with a ranged index of 68.8 to 78.4 percent. This work can be a tool for assessing forest quality at landscape level for decision support in sustainable landscape management and can be applied on other regions.

Spatial analysis of early mangrove regeneration in the Matang Mangrove Forest Reserve, Peninsular Malaysia, using geomatics

Successful mangrove tree regeneration is required to maintain the provision of wood for silviculturally managed mangrove forest areas and to ensure mangrove rehabilitation in disturbed areas. Successful natural regeneration of mangroves after disturbance depends on the dispersal, establishment, early growth and survival of propagules. Focusing on the Matang Mangrove Forest Reserve (MMFR) in Peninsular Malaysia, we investigated how the location of a mangrove forest patch might influence the early regeneration of mangroves after clear-felling events that regularly take place on an approximately 30-year rotation as part of local management. We used Landsat-derived Normalized Difference Moisture Index (NDMI) annual time series from 1988 to 2015 to indicate the recovery of canopy cover during early regeneration, which was determined as the average time (in years) for the NDMI to recover to values associated with the mature forests prior to their clear felling. We found that clear-felled mangrove patches closer to water and/or to already established patches of Rhizophora regenerated more rapidly than those farther away. In contrast, patches located closer to dryland forests regenerated slower compared to patches that were farther away. The study concludes that knowledge of the distribution of water, hydro-period and vegetation communities across the landscape can indicate the likely regeneration of mangrove forests through natural processes and identify areas where active planting is needed. Furthermore, time-series comparisons of the NDMI during the early years of regeneration can assist monitoring of mangrove establishment and regeneration, inform on the success of replanting, and facilitate higher productivity within the MMFR.

Migratory Pattern of the Spotted Scat (<i>Scatophagus argus</i>) in the Mangrove Estuary of the Matang Mangrove Forest Reserve, Malaysia, Estimated by Stable Isotope Analysis

Migratory Pattern of the Spotted Scat (<i>Scatophagus argus</i>) in the Mangrove Estuary of the Matang Mangrove Forest Reserve, Malaysia, Estimated by Stable Isotope Analysis

Risk Assessment of Heavy Metal Concentrations in Sediments of Matang Mangrove Forest Reserve

Matang Mangrove Forest Reserve (MMFR) is one of the most productive and managed forests in the world. On the other hand, it has become a concern whether MMFR is being degraded as a result of exposure to industrial pollution. Industries located around MMFR dispose effluents contaminated by heavy metals. This study was conducted to analyze heavy metal contamination and risk assessment status in MMFR sediments. Sediment samples from six compartments were collected based on age and location of the mangrove plantation. Total metal digestion and modified sequential extraction were performed to estimate the concentration of heavy metals. Based on the estimation, risk assessment code, geo-accumulation index, pollution load index, and contamination factor were computed to classify the compartments according to their contamination and pollution levels. Organic matter and sediment texture (silt, clay, and sand content) were also analyzed to find its correlation with heavy metals. According to the results, high concentrations for Copper, Nickel, and Cadmium were observed in Compartment 42, while Compartment 18 and Compartment 74 showed higher concentrations for Zinc and Lead. Heavy metals showed weak positive correlation with clay and silt, but weak negative correlation with sand. For organic matter, only Zinc showed statistically significant but weak negative correlation. Risk assessment code, geo-accumulation index, pollution load index, and contamination factor categorized the compartments into unpolluted to moderately polluted. Based on the study outcomes, it can be concluded that MMFR, although acquiring industrial discharge, is not with a high risk of heavy metal contamination.

Phytoextraction Potential of Rhizophora Apiculata: A Case Study in Matang Mangrove Forest Reserve, Malaysia

Disposal of industrial wastewater has resulted in increased concentration of heavy metals (HMs) along the coastline of Malaysia. However, little is known about the accumulation capacity of HMs by Rhizophora apiculata in Matang Mangrove Forest Reserve (MMFR) Malaysia. The aim of this study is to measure the concentration of HMs in different ages of mangrove forests. In this study, 15 and 80-year old trees of Rhizophora apiculata were selected for experimentation. Thirty samples of leaves, roots and sediments were analyzed to measure the concentration of HMs in 15 and 80-year-old trees. The measured concentrations of copper (Cu), iron (Fe), manganese (Mn) and zinc (Zn) in leaves, roots and sediments were used to compare bio- concentration and translocation factor between the abovementioned two age groups. Concentration of Mn came out to be significantly higher in leaves than in sediment. This suggested that Rhizophora apiculata was an efficient Mn-extractor. On the other hand, it was found less efficient in extracting heavier metals (Fe, Cu and Zn) from the sediment, as their concentration was lower in leaves and roots as compared to sediments. The translocation factor was highest for Mn, indicating high mobility of Mn from roots towards the leaves. Bio-concentration factor was also found highest for Mn (3.52) followed by Zn (1.88), Cu (1.33) and Fe (0.26). Therefore, it can be concluded that Rhizophora apiculata is more efficient in extracting Mn as compared to Zn, Cu and Fe.