Forest In Peninsular Malaysia Research Articles

Vegetation structure and relative humidity drive the diurnal foraging activity of Malaysian giant ant workers in urban fragmented forests

Abstract The impacts of urban forest fragmentation on tropical ant foraging activity are poorly understood. The Malaysian giant ant (Dinomyrmex gigas) is among the largest ant species worldwide. Colonies of this species contribute to important ecosystem processes such as predation and nutrient cycling in the tropical forests of Southeast Asia. Here, we compared the diurnal foraging activity of D. gigas workers in urban‐fragmented and contiguous forests, and investigated how this was shaped by key environmental factors such as vegetation structure and microclimate. Specifically, we sampled ground‐foraging D. gigas workers in four urban/semi‐urban forest patches and two contiguous forests in Peninsular Malaysia across the wet and dry seasons. Surprisingly, we found that some urban forest patches, irrespective of area, supported greater foraging activity of D. gigas workers than contiguous forests. These differences in foraging activity were explained by differences in multiple stand‐level variables between urban forests patches and contiguous forests. Specifically, the abundance of foraging D. gigas workers increased with number of trees with Diamater at breast height (DBH) 5–30 cm, but it decreased with relative humidity, canopy cover, number of palms, number of shrubs and trees with DBH <5 cm. Our study highlights the importance of urban forest patches, microclimate and vegetation structure for driving the diurnal foraging activity of Malaysian giant ant. Small and relatively large forest patches were of comparable importance for the maintenance of biodiversity in urban landscapes. In the absence of landscape connectivity, reforestation is the most feasible option to restore the natural habitat of D. gigas in urban forest patches and mitigate microclimatic edge effects.

Forest Fire Incident Forecasting System In Permanent Reserved Forest In Peninsular Malaysia Using Big Data Analytics

Purpose – This paper summarized the research project on the implementation of big data analytics to forecast the forest fire incident in Peninsular Malaysia. Design/methodology/approach – The research project has developed a Forest Fire Incident Forecasting System in Permanent Reserves Forest (PRF) to forecast forest fire incidence in Peninsular Malaysia. This project was conducted for the Forestry Department Peninsular Malaysia (JPSM) in collaboration with the Ministry of Natural Resources, Environment and Climate Change (NRECC) using Big Data Analytics (BDA). Findings – The results from the system have been summarized into four conclusions. Firstly, the forecast of areas with fire potential can be identified as early as 7 days; secondly, the location of relevant agencies to deal with forest fires close to the site of the fire incident can be identified. Third, the water source close to the fire scene can be located; and finally, the estimated cost of the extinguishing operation can be determined in advance. Practical Implications - To overcome these obstacles and accomplish wise forest management, modern science, and technology must be improved. This research project has successfully implemented BDA via the Forest Fire Incident Forecasting System in PRF. It has improved the performance of the JPSM for its forest management system. Originality – The project is originally conducted with collaborations between the JPSM and NRECC in the Malaysian federal government and has been successfully implemented by the forestry department.

Habitat Ecology, Structure Influence Diversity, and Host-Species Associations of Wild Orchids in Undisturbed and Disturbed Forests in Peninsular Malaysia

As an attempt to examine the causes of forest disturbance and degradation of the orchid community, a comparative study on diversity and ecology in eight undisturbed and ten disturbed forests in Peninsular Malaysia was conducted that varied in areas, elevations, vegetation types, and disturbance regimes. Density and individual-based rarefaction curves were used to describe the abundance. Univariate and multivariate analyses were also performed to explore the associations of species abundance with biotic and abiotic factors. The study reported 239 orchid species belonging to 65 genera. Species richness, abundance, density, and diversity of orchids varied by locality. Higher density of orchids (2.433 plants/km2) occurred in the undisturbed forests than in the disturbed forests (0.228 plants/km2). As with the character of undisturbed forests, the temperature was between 27.8 ± 0.3 °C and 31.2 ± 0.2 °C, humid (77.1 ± 1.2%–89.6 ± 0.9%), and with low light intensity (23.8 ± 3.3 μmol m−2s−1–171.7 ± 18.8 μmol m−2s−1), thus supporting the high density of the plants. Disturbed forests had higher diversity (H = 4.934 and 1-D = 0.990) and abundance (183 species of 57 genera) but were determined to be highly influenced by the higher abundance of epiphytic orchids on the fallen trees and ease of accessibility in the logged forests. Terrestrial and mycoheterotroph orchids were much lower in density and abundance in the disturbed habitat indicating a gradual reduction in their niche availability following the disturbance. Additionally, the ecology data show that the microclimate conditions of the canopy-covered forest was influenced by proximity to the logged area which had eventually reduced the orchids’ habitat quality. Furthermore, the results show that the abundance of epiphytic orchid communities was associated with the host plant characteristics. Host types and bark texture preference were apparent for the epiphytic orchid species, with certain types and textures hosting more orchid species than others. Overall results show that extreme temperature, humidity, and light intensity caused by the canopy opening inflicted damages to the habitat conditions and bark textures of the host plants and limits recolonisation of the orchids in the disturbed forests. The species diversity and density patterns of orchids in undisturbed and disturbed forests revealed in this study provide a baseline for conservationists, policy makers, and forest authorities in expanding the understanding of the forest ecology and vegetation along the disturbance gradient, forest regeneration, and criteria for plant selection for forest restoration in Peninsular Malaysia.

Socio-economic and ecological outcomes of a community-based restoration of peatland swamp forests in Peninsular Malaysia: A 5Rs approach

Restoration of degraded forest lands is a global priority that aims to restore ecosystems and their functions in ways that provide multiple socio-economic benefits. The Selangor State Forestry Department (SSFD) of peninsular Malaysia in collaboration with an NGO, local people and other stakeholders had been implemented a community-based restoration of degraded peat swamp forest (1000 hectare) programme in Raja Musa Forest Reserve, North Selangor since 2008. However, socio-economic and ecological impacts of this restoration programme are yet to study fully. In this pioneer study, we followed 5Rs approach to peatland restoration and assessed rewetting status (R1), reduction of fire incidences (R2), revegetation (R3), revitalization (R4) and reporting and monitoring (R5) to understand socio-economic and ecological outcomes of the programme. Data on R1, R2, R3 (restoration approach), R4 (qualitative data on socio-economic outcomes) and R5 (management actions and stakeholders’ participation) were collected through four focus group discussions, five key informant interviews, review of NGO’s documents and a stakeholders’ workshop. Quantitative data on R4 (local peoples’ willingness to contribute (WTC) and socio-economic impact (e. g. benefits, education, awareness) were collected through structured interviews of 200 randomly selected households in four surrounding villages. Data on R3 (ecological outcomes- survival rate and growth of planted trees, status of natural regeneration) were gathered through a series of vegetation survey. Restoration project created jobs (e. g. patrolling) and small business (e. g. forest nursery) opportunities for local people, and enhanced tourism, nature education and research in RMFR thus contributed to locals’ socio-economic development (R4). Local people were WTC to tree planting and maintenance (69 %), canal blocking and maintenance (26 %), forest vigilance (34 %), fire control (35 %), trail construction (27 %), and education and awareness creation (40%) voluntarily without remuneration (R1, R2, R3). The SSFD and NGO adopted an innovative approach of PSF restoration where volunteers (local people and other stakeholders) participated in canals blocking to keep PSF wetted, monthly tree planting events, and education and awareness creation campaigns (R1, R3). Canal blockings helped to maintain a mean ground water level of − 24.96 cm. Due to continuous motivation and awareness creation among surrounding villagers, fire incidents in RMFR were reduced (R2). Between 2008 and 2019, 323.72- hectare plantations were developed mainly with Euodia redlevi tree species and few trees of Shorea leprosula, Myristica lowiana and M. pruinose (R3). Selection of species was done by the SSFD and NGO without input from local people (R5). The mean survival percentage of planted trees was 65%. Mean annual increment (MAI) of diameter and height of E. redlevi decreased from younger plantations (3-year) toward older ones (5-, 7-year) (R3). Overall, MAI (dbh and height) across four tree species between age groups was found significantly different (p = 0.001). Regeneration study identified 16 tree species with an average density of 17,798. E. redlevi was dominant, but only 10.6 % of its regeneration attained young tree stage (R3). Suggestions are made to expedite restoration with diverse tree species (R3) with effective participation of local people (R5) and to ensure post-planting maintenance for greater survival of planted trees (R1, R2, R3).

Floristic Composition of Trees in the Lowland Dipterocarp Forest of Kuala Keniam, Taman Negara, Pahang, Peninsular Malaysia

Abstract A study was conducted to determine the floristic composition and community structure of trees in lowland dipterocarp forest in Kuala Keniam, Taman Negara, Pahang. This forest is classified as a primary forest and among the oldest rain forest in the world. Five experimental plots with the dimension of 25 m x 20 m each (0.25 ha in total) had been established. The census was carried out for all trees with diameter at breast height (DBH) 5 cm and above. Species composition comprised of 244 individuals from 141 species, 94 genera and 36 families. The total number of taxa is varying across the five plots with the highest total number of families and species recorded in plot 5 with 21 and 43 taxa each. The lowest total number of families and species were recorded in plot 1 with only 14 families and 23 species. Euphorbiaceae is the most speciose family with 20 taxa and 66 individuals followed by Annonaceae with 14 taxa and 19 individuals. These two families are common in the lowland dipterocarp forests in Peninsular Malaysia. Main canopy and understorey and group were recorded with the highest number of species and individuals with 52 and 45 of species and 91 and 75 of individuals, respectively. Pioneer is very rare and was only represented by a single stem of Cratoxylum formosum and Sapium baccatum. Three species, namely Koompassia malaccensis, Elateriospermum tapos and Mallotus leucodermis were represented as the highest total number of individuals for DBH classes of ≥ 5 cm, ≥ 10 cm, ≥ 15 and ≥ 20 cm.

Occupancy of wild southern pig-tailed macaques in intact and degraded forests in Peninsular Malaysia.

Deforestation is a major threat to terrestrial tropical ecosystems, particularly in Southeast Asia where human activities have dramatic consequences for the survival of many species. However, responses of species to anthropogenic impact are highly variable. In order to establish effective conservation strategies, it is critical to determine a species’ ability to persist in degraded habitats. Here, we used camera trapping data to provide the first insights into the temporal and spatial distribution of southern pig-tailed macaques (Macaca nemestrina, listed as ‘Vulnerable’ by the IUCN) across intact and degraded forest habitats in Peninsular Malaysia, with a particular focus on the effects of clear-cutting and selective logging on macaque occupancy. Specifically, we found a 10% decline in macaque site occupancy in the highly degraded Pasoh Forest Reserve from 2013 to 2017. This may be strongly linked to the macaques’ sensitivity to intensive disturbance through clear-cutting, which significantly increased the probability that M. nemestrina became locally extinct at a previously occupied site. However, we found no clear relationship between moderate disturbance, i.e., selective logging, and the macaques’ local extinction probability or site occupancy in the Pasoh Forest Reserve and Belum-Temengor Forest Complex. Further, an identical age and sex structure of macaques in selectively logged and completely undisturbed habitat types within the Belum-Temengor Forest Complex indicated that the macaques did not show increased mortality or declining birth rates when exposed to selective logging. Overall, this suggests that low to moderately disturbed forests may still constitute valuable habitats that support viable populations of M. nemestrina, and thus need to be protected against further degradation. Our results emphasize the significance of population monitoring through camera trapping for understanding the ability of threatened species to cope with anthropogenic disturbance. This can inform species management plans and facilitate the development of effective conservation measures to protect biodiversity.

DNA-based taxonomy of a mangrove-associated community of fishes in Southeast Asia

The Merbok Estuary comprises one of the largest remaining mangrove forests in Peninsular Malaysia. Its value is significant as it provides important services to local and global communities. It also offers a unique opportunity to study the structure and functioning of mangrove ecosystems. However, its biodiversity is still partially inventoried, limiting its research value. A recent checklist based on morphological examination, reported 138 fish species residing, frequenting or subject to entering the Merbok Estuary. In this work, we reassessed the fish diversity of the Merbok Estuary by DNA barcoding 350 specimens assignable to 134 species initially identified based on morphology. Our results consistently revealed the presence of 139 Molecular Operational Taxonomic Units (MOTUs). 123 of them are congruent with morphology-based species delimitation (one species = one MOTU). In two cases, two morphological species share the same MOTU (two species = one MOTU), while we unveiled cryptic diversity (i.e. COI-based genetic variability > 2%) within seven other species (one species = two MOTUs), calling for further taxonomic investigations. This study provides a comprehensive core-list of fish taxa in Merbok Estuary, demonstrating the advantages of combining morphological and molecular evidence to describe diverse but still poorly studied tropical fish communities. It also delivers a large DNA reference collection for brackish fishes occurring in this region which will facilitate further biodiversity-oriented research studies and management activities.

Comparison of terrestrial vertebrates between natural and teak plantation forest in Peninsular Malaysia: A case study in Perlis State Park and Mata Ayer Field Center, FRIM

Species compositions are influenced by the habitat types and methods used in a study. The objectives of this study are to document species diversity in teak plantation in Mata Ayer Research Station, FRIM and to compare differences in species diversity and composition between plantation and natural forest of Perlis State Park. Different types of traps and methods were used to survey four targeted groups of vertebrates (small mammal, bird, reptile and amphibian), including mist net, harp trap, collapsible trap, and active search. A total of 252 individuals were captured, representing 117 species of 53 families of vertebrates. Alpha diversity analysis shows that natural forest has higher species diversity than a teak plantation. Shannon-Weiner Index show higher result in natural forest (3.768) than teak plantation (3.439) while evenness of species distribution is higher in teak plantation (0.8419) than the natural forest (0.4755). Sorenson dissimilarity index indicates that 90.4% significant difference between sites thus; both sites have different species composition of vertebrates. Taxonomic distinctness however reflects different significant variation responses of both areas. Natural forest shows more species compared to plantation forest as it provides more food resources, suitable home and higher rate of reproduction while teak plantation shows a similar habitable environment with structural and conditions more similar to natural forest. So, both natural forest and plantation should be protected, manage and use suitable planning in order to sustain the biodiversity for future generation.

Effects of vegetation structure on avian biodiversity in a selectively logged hill dipterocarp forest

Southeast Asian tropical rainforests are shrinking at an alarming rate largely due to anthropogenic activities such as logging and agricultural expansion. The loss of tropical rainforests from human exploitations caused devastating and irreversible impacts on avian biodiversity. The establishment of protected areas is an effective tool to mitigate further forest biodiversity loss. However, the ability of degraded rainforest to support avian biodiversity is still remain little known. Here, we assessed bird assemblages in a hill dipterocarp forest in Peninsular Malaysia which was selectively logged almost three decades ago. We examined the effects of site-level attributes, particularly vegetation structure on bird community composition, species richness and abundance of selected feeding guild groups (i.e. insectivorous, carnivorous, and frugivorous). Generally, we found that a selectively logged hill dipterocarp forest can still support a large proportion of forest birds, including those species with high conservation values. Our data also revealed that avian biodiversity was positively related to the number of fallen snags, number of standing snags, number of shrubs, number of trees with DBH < 5 cm, and elevation. In contrast, avian biodiversity was negatively linked to canopy cover percentage, number of palms, and number of trees with DBH 30–50 cm. Our findings suggest the importance of post-harvest site-level attributes management in order to improve avian biodiversity in logged hill dipterocarp forests. Above all, urgent actions are needed to incorporate hill dipterocarp forests, including those already disturbed by logging into protected area networks in Peninsular Malaysia to mitigate forest biodiversity loss.

Diversity and ecology of araceae in the water catchment area of Ulu Sat, Kelantan, Peninsular Malaysia

Araceae or aroid is familiarly known as keladi to the locals. The purpose of this study is to assess the diversity and ecology of Araceae in the Water Catchment Area of Ulu Sat, Kelantan, Peninsular Malaysia. The random sampling method was applied. A total of 26 species from 13 genera of Araceae were recorded from the water catchment area of Ulu Sat, Machang, Kelantan, Peninsular Malaysia. This represents about 18.6% out of an estimated 140 species and 46.2% of the 28 genera of Araceae reported for Peninsular Malaysia. The result also shows that 24 species or 92.3% of the collection are the common Araceae species found in lowland dipterocarp forest in Peninsular Malaysia. However, the collection include the species recently recorded, Aglaonema cochinchinense Engl. and the endemic species, Alocasia puber (Hassk.) Schott for Peninsular Malaysia. The paper will also discuss the distribution and ecology of some important Araceae collected from this area.

DIVERSITY AND VERTICAL DISTRIBUTION OF VASCULAR EPIPHYTES ON A MALAYSIAN MANGROVE ISLAND

Many studies have attempted to explain the diversity and abundance of epiphytic plants in major ecosystems, worldwide. However, investigations on the abundance of epiphytic plants in mangroves have remained rare. The aim of this research was to study the diversity and vertical distribution of vascular epiphytes in a mangrove forest in peninsular Malaysia. The sampling was done over a 0.1 hectare of Pulau Telaga Tujuh, a mangrove island in Terengganu, Malaysia. Trees with vascular epiphytes were divided into three strata: basal, trunk and canopy. The vascular epiphytes were identified, and the number of individuals in each stratum was recorded. In total, 8 species of vascular epiphytes from 6 genera and 4 families were recorded. Pulau Telaga Tujuh mangrove forest exhibited a relatively low diversity of vascular epiphytes (H’ = 1.43). The dominance of Hydnopytum formicarum significantly contributed to the diversity of vascular epiphytes in this forest. The highest abundance of epiphytes was observed on the trunks of the host trees. The vertical distribution pattern observed in this study is associated with the adaptation of the epiphytic plants to stresses in the mangrove ecosystem, particularly, drought and salt spray. Pulau Telaga Tujuh had a high density of vascular epiphytes but lower diversity compared with other ecosystems.

Vegetation Indices for Identifying Melaleuca Forest from Multispectral Satellite Sensors

Melaleuca forest or locally known as Gelam forest mostly occur in beach ridges interspersed with swales (BRIS) sandy areas, coastal, wetland, peatland, and lowland regions. It is a mono-specific species dominance ecosystem, where Melaleuca cajuputi trees are dominant. It is fringing along the coast of Terengganu and Kelantan and certain parts along the west coast of Peninsular Malaysia. The landscape is small but it has equal importance to other ecosystems in terms of local environmental functions and economic contributions. The benefits include timber for building constructions and furniture and other traditional uses, such as for fuel wood, charcoal, tea-tree, honeybee breeding areas and others. However, this forest is inevitable from threats by anthropogenic activities such as land clearing and conversion to other land uses that can affect the ecosystem. These activities occur because most of this ecosystem reside on stateland areas, where development is rapid. Only small patches of this forest was protected as Permanent Forest Reserve, which is secure from any threat. Currently the information about the tracts and extents of this forest is very scarce. Therefore, this study was carried out to acquire latest information on the distribution and extent of Melaleuca forest in Peninsular Malaysia through the utilization of remotely sensed data. Optical images from Landsat-8 OLI were used as primary input for this study. Spectral characteristic from visible and infrared regions were analyzed to produce a specific vegetation index for recognizing Melaleuca forest ecosystem on the images. The study demonstrated that the Melaleuca forest covers some 23,000 ha in Peninsular Malaysia that are intact but vulnerable to surrounding threats. The findings of study should attract attentions from the relevant State Governments to take appropriate management actions to protect this unique and priceless ecosystem in the future.

Tree Diversity, Stand Structure, and Community Composition in an Island Forest of Pulau Perhentian Besar, Terengganu

The Perhentian Island Archipelago comprising of 11 small islands is located in the state of Terengganu are among the biodiversity rich localities in Peninsular Malaysia. Perhentian Besar with approximately 867 hectares is one of the inhabited island and become the centre of tourism besides Perhentian Kecil. Island is well known as a place for many endemic and endangered living organism as previously demonstrated on other similar forested islands in Southeast Asia. However, there is little attention and effort of protection has been received by the terrestrial ecosystems that reside nearby the coastal. Thus, the present study investigates on tree diversity, stand structure and community composition in the island of Perhentian Besar, Terengganu. Forest plot of 0.5 hectare was established to analyze the floristic composition of tree taxa. The plot was divided into 10 subplots of 25m x 20m. All trees with 5cm diameter breast height (dbh) and above were tagged, measured for dbh size, recorded and identified. Voucher specimens were taken for further verification purposes. A total of 102 tree species were recorded comprising of 28 families and 65 genera. Rubiaceae had the highest number of species (11 species) and with regards to relative dominance, Shorea leprosula (Dipterocarpaceae) gave the highest importance value index (IVi) for species with a value of 8.45%. The Shannon-Weiner Diversity Index (H’) was considered high in the present study with 3.94 (H’max = 4.62) and the Evenness Index (E) value of 0.85 indicated that all species in the present study are almost equally abundant. The forest stand structure had a reverse J-shaped curve for tree size-class distributions as frequently observed in many natural forests, which indicated that the forest stand in the study site had a good recruitment patterns and also a main feature of matured forest in Peninsular Malaysia. The present study will help us to understand the pattern of tree species composition, diversity and forest ecosystem dynamic in Pulau Perhentian Besar.

Coleoptera of Genting Highland, Malaysia: species richness and diversity changes along the elevations

The objective of this study was to measure beetle richness and diversity in Genting Highland at four major elevations (500 m, 1,000 m, 1,500 m and 1,800 m). Beetles were collected using light traps, malaise traps and pitfall traps. Altogether, 1,499 beetle samples representing 156 morphospecies were collected. Light trap and pitfall traps were more effective than Malaise trap. The 500 m elevation band displayed high species richness, abundance and diversity with all indices showing a decreasing pattern. The species accumulation curve displayed a progressive asymptote for all the altitudinal transects, showing the sampling effort was sufficient for this study. A long-term monitoring program of beetle diversity and distribution is useful to test abiotic factors that might influence biodiversity. This study also serves as a benchmark for further studies on this highly disturbed montane cloud forest in Peninsular Malaysia and will be useful to implement effective conservation management, particularly under the threat of climate change.

Spatial variations of soil silicon availability and biogenic silicon flux in a lowland tropical forest in Malaysia

AbstractTropical tree species differ widely in their silicon (Si) accumulation patterns, but the implications of such species differences for ecosystem Si flux remain unexplored. We analyzed how biogenic Si flux via leaf litter and soil Si availability in the upper soil vary spatially within a 2 ha area in a lowland Dipterocarp forest in Peninsular Malaysia. Silicon concentration per unit leaf dry mass of 86 dominant tree species in this plot ranged from 0.4 to 126 mg/g. Soil Si availability at 100 sampling points and Si flux via leaf litter at 66 litter traps showed large variations up to 3.3‐ and 17.9‐folds, respectively. However, they correlated neither with each other nor with the expected Si flux from tree species composition in the neighborhood. When we classified tree species to four groups by their leaf Si concentrations (negligible, low, moderate and high), tree species with moderate leaf Si concentrations were significantly more abundant on Si‐rich soils. In contrast, the other three groups did not show any significant spatial relationships with soil Si availability. These results indicate that soil Si availability, Si accumulation by vegetation and Si flux via leaf litter show wide spatial variations in a lowland tropical forest, without a simple relationship with each other.

Urban forest fragmentation impoverishes native mammalian biodiversity in the tropics.

Urban expansion has caused major deforestation and forest fragmentation in the tropics. The impacts of habitat fragmentation on biodiversity are understudied in urban forest patches, especially in the tropics and little is known on the conservation value of the patches for maintaining mammalian biodiversity. In this study, camera trapping was used to determine the species composition and species richness of medium‐ and large‐sized mammals in three urban forest patches and a contiguous forest in Peninsular Malaysia. We identified the key vegetation attributes that predicted mammal species richness and occurrence of herbivores and omnivores in urban forest patches. A total number of 19 mammal species from 120 sampling points were recorded. Contiguous forest had the highest number of species compared to the urban forest patches. Sunda Pangolin and Asian Tapir were the only conservation priority species recorded in the urban forest patches and contiguous forest, respectively. Top predators such as Malayan Tiger and Melanistic Leopard were completely absent from the forest patches as well as the contiguous forest. This was reflected by the abundance of wild boars. We found that mammal species richness increased with the number of trees with DBH less than 5 cm, trees with DBH more than 50 cm, and dead standing trees. In the future, the remaining mammal species in the urban forest patches are expected to be locally extinct as connecting the urban forest patches may be infeasible due to land scarcity. Hence, to maintain the ecological integrity of urban forest patches, we recommend that stakeholders take intervention measures such as reintroduction of selected species and restocking of wild populations in the urban forest patches to regenerate the forest ecosystems.

Are secondary forests second-rate? Comparing peatland greenhouse gas emissions, chemical and microbial community properties between primary and secondary forests in Peninsular Malaysia

Tropical peatlands are globally important ecosystems with high C storage and are endangered by anthropogenic disturbances. Microbes in peatlands play an important role in sustaining the functions of peatlands as a C sink, yet their characteristics in these habitats are poorly understood. This research aimed to elucidate the responses of these complex ecosystems to disturbance by exploring greenhouse gas (GHG) emissions, nutrient contents, soil microbial communities and the functional interactions between these components in a primary and secondary peat swamp forest in Peninsular Malaysia. GHG measurements using closed chambers, and peat sampling were carried out in both wet and dry seasons. Microbial community phenotypes and nutrient content were determined using phospholipid fatty acid (PLFA) and inductively-coupled plasma mass spectrometry (ICP-MS) analyses respectively. CO2 emissions in the secondary peat swamp forest were > 50% higher than in the primary forest. CH4 emission rates were ca. 2 mg m−2 h−1 in the primary forest but the secondary forest was a CH4 sink, showing no seasonal variations in GHG emissions. Almost all the nutrient concentrations were significantly lower in the secondary forest, postulated to be due to nutrient leaching via drainage and higher rates of decomposition. Cu and Mo concentrations were negatively correlated with CO2 and CH4 emissions respectively. Microbial community structure was overwhelmingly dominated by bacteria in both forest types, however it was highly sensitive to land-use change and season. Gram-positive and Gram-negative relative abundance were positively correlated with CO2 and CH4 emissions respectively. Drainage related disturbances increased CO2 emissions, by reducing the nutrient content including some with known antimicrobial properties (Cu & Na) and by favouring Gram-positive bacteria over Gram-negative bacteria. These results suggest that the biogeochemistry of secondary peat swamp forest is fundamentally different from that of primary peat swamp forest, and these differences have significant functional impacts on their respective environments.

Time-series maps of aboveground biomass in dipterocarps forests of Malaysia from PALSAR and PALSAR-2 polarimetric data

BackgroundMalaysia typically suffers from frequent cloud cover, hindering spatially consistent reporting of deforestation and forest degradation, which limits the accurate reporting of carbon loss and CO2 emissions for reducing emission from deforestation and forest degradation (REDD+) intervention. This study proposed an approach for accurate and consistent measurements of biomass carbon and CO2 emissions using a single L-band synthetic aperture radar (SAR) sensor system. A time-series analysis of aboveground biomass (AGB) using the PALSAR and PALSAR-2 systems addressed a number of critical questions that have not been previously answered. A series of PALSAR and PALSAR-2 mosaics over the years 2007, 2008, 2009, 2010, 2015 and 2016 were used to (i) map the forest cover, (ii) quantify the rate of forest loss, (iii) establish prediction equations for AGB, (iv) quantify the changes of carbon stocks and (v) estimate CO2 emissions (and removal) in the dipterocarps forests of Peninsular Malaysia.ResultsThis study found that the annual rate of deforestation within inland forests in Peninsular Malaysia was 0.38% year−1 and subsequently caused a carbon loss of approximately 9 million Mg C year−1, which is equal to emissions of 33 million Mg CO2 year−1, within the ten-year observation period. Spatially explicit maps of AGB over the dipterocarps forests in the entire Peninsular Malaysia were produced. The RMSE associated with the AGB estimation was approximately 117 Mg ha−1, which is equal to an error of 29.3% and thus an accuracy of approximately 70.7%.ConclusionThe PALSAR and PALSAR-2 systems offer a great opportunity for providing consistent data acquisition, cloud-free images and wall-to-wall coverage for monitoring since at least the past decade. We recommend the proposed method and findings of this study be considered for MRV in REDD+ implementation in Malaysia.

Estimation of carbon pool in soil, above and below ground vegetation at different types of mangrove forests in Peninsular Malaysia

This paper evaluated the total carbon stock of mangrove ecosystems in two contrasting sites: a fishing village in Delta Kelantan (DK) and Ramsar sites in Johor Park (JP). In both sites, aboveground carbon was significantly higher than belowground carbon, and stems contained more carbon than leaf and root partitions. The average carbon concentration of individual mangrove species (44.9–48.1%) was not significantly different but the larger biomass of the DK samples resulted in vegetation carbon stock that was higher than that in JP. Season played an important role in soil carbon stock—a pronounced wet season in DK coincided with the dry season in JP. The total carbon pool was estimated to be 427.88 t ha−1 in JP and 512.51 t ha−1 in DK, where at least 80% was contributed by soil carbon. The carbon dioxide equivalent was 1570.32 t ha−1 CO2e (JP) and 1880.91 t ha−1 CO2e (DK).

Selective logging causes the decline of large-sized mammals including those in unlogged patches surrounded by logged and agricultural areas

Legal and illegal logging is prevalent throughout the tropics, impacting on natural habitat and wildlife. This study aimed to investigate the sensitivity of forest mammals to selective logging in the lowland dipterocarp forests of South-West Peninsular Malaysia and identify the underlying factors that determine species occurrence. A total of 120 camera trap locations were deployed within selectively logged and unlogged forests. We found that unlogged forest had greater wildlife occurrences compared to selectively logged forests, including two endangered mammal species not found in logged forest. Forest vegetation structure characteristics such as the abundance of lianas, large trees, saplings, palms, bamboo and seedlings were associated with mammal species richness. Mammal species richness increased with number of forest trees, particularly those with a DBH of >45 cm, but this was limited to high altitude forest. Worryingly, we did not detect any large mammalian apex predators such as leopards or tigers in either unlogged or selectively logged forests. The absence of these animals may be the result of poaching, habitat degradation or other pressures; these mammals are expected to be present in intact forests in Peninsular Malaysia. Restoring logged forests and preserving the remaining unlogged lowland dipterocarp forests are critically important to safeguard mammalian biodiversity in the region. Besides that, we recommend that conventional logging practices are replaced with reduced impact logging methods.