Heath Forest Research Articles

GENETIC DIVERSITY OF NEPENTHES GRACILIS IN HEATH FOREST IN SOUTH AND CENTRAL PARTS OF KALIMANTAN

Nepenthes gracilis is found in the lowlands in the form of peat swamp forest, heath forests and is widely distributed in Thailand, Sumatra, Peninsular Malaysia, Singapore, Kalimantan, and Sulawesi. The unique characteristics of the plant, potential benefits and threats of declining population of N. gracilis impacted this plant as a conservation priority in the heath forest. Characterization of N. gracilis applied before implementing conservation actions. The conservation approach proceeded by analyzing the genetic diversity of N. gracilis from various types of heath forest. The research object used as genetic material was the leaf part of N. gracilis. The sampling locations of N. gracilis were in the heath forest of Guntung Ujung village, Gambut sub-district, Banjar regency, South Kalimantan (Location 1), heath forest in Tabalong Regency, South Kalimantan (Location 2), heath forest in East Kotawaringin Regency, Central Kalimantan (Location 3), heath forest of the Nyaru Menteng Arboretum, Palangkaraya, Central Kalimantan (Location 4). The tools and materials used for genetic analysis with PCR-RAPD markers are divided into several stages of work: DNA extraction, DNA quality and quantity testing, DNA visualization, and data analysis. The results show that OPP-09 and OPBH-20 were the primers with the highest amplification success for N. gracilis plants from the heath forest and the amplification values are 52.5% and 51.25%. The percentages of polymorphism bands were 97.62% and 95.24%, respectively. Disturbed heath forest with open canopy cover showed an indication of low genetic diversity shown by N. gracilis originating from location 1 and location 4 of heath forests and the highest genetic diversity value, and the highest percentage of locus polymorphism value (79%) was shown by N. gracilis location 3 with relatively undisturbed forest cover and classified as old growth. It is crucial to preserve the heath forest cover from damage to maintain high genetic diversity of N. gracilis. Genetic relationships between populations can be a barometer in conservation programs for N. gracilis.

UJI KANDUNGAN SIFAT FISIK DAN KIMIA LAHAN GAMBUT DI KAWASAN HUTAN DENGAN TUJUAN KHUSUS MUNGKU BARU

According to law no.14 year 1999 about forestry, forest by its function divided into conservation forest, protected forest and production forest. Forest area with special purposed as education forest on permanent production forest at Palangkaraya, area 4,910 ha. Forest area with Special Purpose as Educational Forest in the Mungku Baru Forest Area is located at an altitude of about 60 above sea level with hilly topography and it has several tributaries and has a variety of forest types, namely peat swamp forest, heath forest around the Rakumpit watershed. and lowland dipterocarp forest. Based on the distribution area of ​​the peat area, researchers are interested in testing the physical properties of peatlands and sandy peat in the Mungku Baru KHDTK area, which previously conducted research on plant diversity in the Mungku Baru KHDTK area, Palangka Raya City. The purpose of this study was to determine the physical and chemical properties of peatlands in the KHDTK Mungku Baru area. The research method used is quantitative. Based on the results of the study, the physical properties of peatlands in three locations stated that the BD value was below 1, which had a value of 0.187 to 0.272. It means that the peat is formed from organic matter so it has a low BD and the maturity of peatlands is classified as febrile. While the chemical properties in the three locations are the content of N-Total, C-orgagic, C/N, P2O5, K2O, dissolved Fe, pH, Ca-dd, Mg-dd, Na-dd, K-dd, CEC, and KB

Diversity and ecology of Pteridophytes in Cendil heath forest and Gurok Beraye tropical rainforest, Belitung Island, Indonesia

Abstract. Priambudi AS, Chikmawati T, Sulistijorini, Fakhrurrozi Y. 2022. Diversity and ecology of Pteridophytes in Cendil heath forest and Gurok Beraye tropical rainforest, Belitung, Indonesia. Biodiversitas 23: 4775-4782. The tropical heath forest is a unique ecosystem type characterized by sandy and acidic soils with poor nutrients and water availability, making this ecosystem very vulnerable to disturbances. Yet, knowledge regarding the diversity and ecology of the biological elements of heath forests is still very limited, moreover, information on lesser-known plant groups, such as pteridophytes. Pteridophytes can be used as indicators of the quality of a forest ecosystem since they are cosmopolitan and have an excellent adaptation to various habitats. Belitung Island, Indonesia, is a region with a large proportion of tropical heath forest and small areas of tropical rainforest. There are only a few studies on comparison of the flora of the two ecosystem types on Belitung Island. This research aimed to compare the diversity and the ecology of pteridophytes that grow in the Cendil heath forest and the Gurok Beraye tropical rainforest, Belitung Island. The study used the cruise and the purposive sampling methods to record all pteridophytes within the sampling plots measuring 5 x 5 m alternately located on the right and left of line transects with a length of 50 meters each transect. Ecological data were calculated using the Important Value Index (IVI), Shannon-Wiener diversity index, Margalef richness index, Evenness index, Sorensen similarity index, Morisita distribution index, and Canonical Correspondence Analysis. The results showed that as many as 31 species of pteridophytes belonged to 14 families in the Cendil heath forest and Gurok Beraye tropical rainforest. The pteridophytes found in the Gurok Beraye tropical rainforest were higher (30 species) than that in the Cendil heath forest (9 species). There was high dominance of a few species in the Cendil heath forest due to the presence of three species with high IVI, namely Dicranopteris linearis, Palhinhaea cernua and Dicranopteris splendida. In contrast, pteridophytes in the Gurok Beraye tropical rainforest were evenly distributed with no high dominance species. Environmental parameters that affected the diversity and abundance of pteridophytes included temperature, light intensity, humidity, and altitude.

The potential of medicinal plants from heath forest: Local knowledge from Kelubi Village, Belitung Island, Indonesia

Abstract. Oktavia D, Pratiwi SD, Munawaroh S, Hikmat A, Hilwan I. 2022. The potential of medicinal plants from heath forest: Local knowledge from Kelubi Village, Belitung Island, Indonesia. Biodiversitas 23: 3553-3560. The heath forest ecosystem is home to hundreds of species in Belitung Island and is home to medicinal plant resources. The Belitung people prefer to use medicinal plants due to their easy availability and cheap therapy, compared to costly modern pharmaceuticals. In this study, we investigated the potential of medicinal plants from heath forests according to the local knowledge of the Belitung Malay community. This study was conducted in Kelubi Village, Belitung Island, Indonesia. Data and information related to medicinal plant properties were obtained through interviews with local people using an in-depth interview technique. We documented 86 species belonging to 48 families. The medicinal plants are classified into 48 families. The most abundant families are Rubiaceae (8 species), and Myrtaceae (8 species). Many species from the Myrtaceae family are used as medicinal species, such as, jemang (Rhodamnia cinerea), gelam (Melaleuca leucadendra), keremuntingan (Rhodomyrtus tomentosa), and sekudong pelandok (Syzygium buxifolium). The percentages of medicinal plant diversity based on habitus were 45% trees, 21% woody lianas, 13% small trees, 13% herbs, and 8% lianas. We also found that 23 species of medicinal plants were used as herbs after childbirth, and 10 species of plants were used to treat fever. Belitung Malay people use plants for traditional medicine to solve some diseases and therapy. We suggest that conservation efforts for the heath forest ecosystem should be a priority for the sustainable use of medicinal plants on Belitung Island.

Natural distribution of the genus Dacrydium Lamb. (Podocarpaceae) in Central Kalimantan, Indonesia

Abstract. Maimunah S, Kessler PJA, Indrioko S, Naiem M. 2022. Natural distribution of the genus Dacrydium Lamb. (Podocarpaceae) in Central Kalimantan, Indonesia. Biodiversitas 23: 2816-2822. The tropical coniferous genus Dacrydium is widespread in Kalimantan, Indonesia. It is estimated that four species still exist in Borneo, locally known as Alau. This genus thrives in a range of habitats, from heath to deep-peat forests in Central Kalimantan. This genus is currently threatened by logging, fire, and forest conversion to plantations. The objectives of this study were: 1) to know the distribution and abundance of Dacrydium, and 2) to describe the Dacrydium’s habitat. The research was conducted in a heath forest located in PT Taiyoung Engreen (PTTE) in Gunung Mas District and PT Dasa Intiga (PTDI) in Kapuas and North Barito District, and in deep-peat swamp forest located in Sebangau National Park (SNP) in Palangka Raya and Pulang Pisau District. Data were collected in plots, each measuring 50 x 80 m, and the collected data were analyzed using a biodiversity calculator device created by MSU in USAID Lestari 2019. The identified specimens of alau found were sent to Herbarium Bogoriense for validation. The results of the analysis showed that we could identify three species of alau from the four species that are suspected to exist in Kalimantan. namely Dacrydium beccarii Parl. (alau bakam (B)); Dacrydium pectinatum de Laub. (alau kelangkang (K)), and Dacrydium elatum (Roxb.) Wall. ex Hook. (alau tombak (T)) with various abundance. Depending on the conditions of habitat, Alau could be found only in some parts of heath to deep-peat swamp forest. The finding of D. pectinatum in the study areas is a new discovery because it was previously reported that this species was not found in Central Kalimantan.

Wild Pitcher Plant (Nepenthes: Nepenthaceae) in Lowland of Tanjung Selor: A Notes of Diversity, Conservation and Threats

Borneo is the second-highest diversity island for Nepenthes, with approximately comprising 23 species that were spread on this island. Species found on lowland to highland with variety habitat and ecological types. Tanjung Selor is the capital city of Bulungan Regency, North Kalimantan. Nepenthes distribution in these areas has never been reported, particularly in the heath forest. The study was conducted to report the floristic of Nepenthes in Tanjung Selor. We used a desktop study and field exploration on heath forest of Tanjung Selor in 2019 with rapid biodiversity assessment method. The preliminary report of Nepenthes in Bulungan are presented with species description, ecology, threats, illustration, and a brief disscusion regarding the species. We reported six wild species and one natural hybrid of Nepenthes based on exploration. Nepenthe’s habitat is in an open area, roadside, and heath forest vegetation. The threats are higher from habitat degradation and land conversion to agricultural land or non-agricultural uses. In this paper, we mentioned Nepenthes fusca growth in lowland habitat, commonly found in highland.

Vegetation diversity, structure and composition of three forest ecosystems in Angsana coastal area, South Kalimantan, Indonesia

Abstract. Nugroho Y, Suyanto, Makinudin D, Aditia S, Yulimasita DD, Afandi AY, Harahap MM, Matatula J, Wirabuana PYAP. 2022. Vegetation diversity, structure and composition of three forest ecosystems in Angsana coastal area, South Kalimantan, Indonesia. Biodiversitas 23: 2640-2647. Vegetation communities around coastal ecosystems play important roles in mitigating natural disaster and climate change. However, available information about vegetation communities in coastal areas is still limited despite being a requirement in developing strategies for environmental preservation. Angsana coastal area in South Kalimantan, Indonesia has unique characteristics in which it has three different forest ecosystems, namely heath forest (HF), beach forest (BF), and mangrove forest (MF). This study aimed to identify the vegetation diversity, structure and composition of the three forest ecosystems in Angsana coastal area. A field survey was conducted using transect line methods with a sampling plot size of 10 × 10 m and an interval of 20 m. Vegetation communities were assessed using species abundance, plant diversity, importance value index (IVI), and similarity level. Results showed that 37 species from 25 families were recorded at the study site. The highest species abundance was observed in HF (22 species), followed by BF (18 species) and MF (7 species). The same trend was found for vegetation diversity, in which HF had the highest richness (Dmg = 4.52), heterogeneity (H' = 2.86), and evenness (J' = 0.94). Hibiscus tiliaceus L. had the highest IVI in BF in all vegetation stages, and Rhizophora mucronata Lam. consistently had the greatest IVI in MF in all stages. Species thet exhibited the highest IVI in HF were Adina minutiflora Valeton (seedlings), Rhodedomia tomentosa and Premna serratifolia L. (saplings), Tristania maingayi Duthie (poles), and Vitex ovata Thunb. (trees). Our study also observed that species abundance in forest ecosystems gradually declined from seedlings to trees, except in MF. Among the three forest types, vegetation composition was highly similar between MF and BF, with a similarity level of 47.1%. Based on these results, this study concluded that the three forest ecosystems in Angsana coastal area exhibit a highly diverse vegetation structure, and each type of forest has specific characteristics as its entity.

Roles of Heterogeneous Habitat for Conservation of Nymphalidae in Sarawak (East Malaysia)

Species diversity characterises an area or a targeted habitat and provides information on the species assemblages, which is a primary reflection of habitat diversity. It incorporates both species richness and abundance and may rely on factors, such as host-plant availability and food resources. Kubah National Park is a lowland mixed dipterocarp forest, and uniquely offers various vegetation types, which includes heath and submontane forests. In the present study, four contrasting forest habitats were selected along forest trails, namely, primary forests, secondary forests, heath forests and forest edges. Forty baited traps were used within a six-months of sampling period. The highest abundance was recorded at the heath forest while the least was at the secondary forest. However, there was no significant difference in terms of species abundance between forest habitats for subfamilies, as well as for the 15 most abundant nymphalid species sampled, except for Mycalesis mnasicles. This satyrine was regarded as being able to differentiate habitat, apart from sensitive to canopy openings. Secondary forest provides a heterogeneous habitat for nymphalids, and thus highest diversity was observed here. This study implies that habitat association of the family is crucial, as it will provide information for both species inventory as well as the fluctuation patterns of the nymphalids diversity. Similar study is suggested to be carried out in the future, which incorporates more than one habitat types and in a more extensive period.

Acaciainvasion differentially impacts soil properties of two contrasting tropical lowland forests in Brunei Darussalam

AbstractInvasiveAcaciaspecies are known to modify soil properties, although effects are often site-specific. We examined the impact ofAcaciaspecies on the soils of intact and invaded habitats of two contrasting tropical lowland rain forest types in Brunei Darussalam: heath forest (HF) and mixed dipterocarp forest (MDF). Impacts on soil properties differed between the two forest types. Overall,Acacia-invaded HF soil recorded significantly higher gravimetric water content, pH and total P, K and Ca compared to the intact HF soil. In contrast, invaded MDF soil exhibited significantly higher organic matter content and total soil N, P, K and Mg compared to its intact habitat.Acacia-invaded MDF soils were more nutrient-enriched thanAcacia-invaded HF soils by the addition of threefold, threefold and fourfold total soil P, K and Mg, respectively. The positive effect of addition of total soil Ca was, however, fourfold greater in HF soil than MDF soil, indicating that the magnitude of impact on soil properties was strongly site-specific. Overall,Acaciainvasion significantly impacted soil properties in nutrient-rich MDF more than those of nutrient-poor HFs, indicating a potential vulnerability of MDFs to invasion.

Influence of species functional strategy on leaf stoichiometric responses to fertilizer in a Bornean heath forest

Abstract The distribution of Bornean heath forest on white sand soils is believed to be due to element limitation and soil acidity. To determine the impact of both element limitation and soil acidity on tropical heath forest, we established a soil fertilization experiment to investigate the impact that increased soil N availability and reduced soil pH (using lime/CaCO3) had on a range of elements in tree leaves. We hypothesized that alterations in soil resource availability would cause changes in the tree leaf N:P ratio and concentrations of other elements and these changes would be influenced by species' functional strategies. The experiment was carried out in a Bornean heath forest on infertile soil over a 2‐year period. We selected 10 common tree species, spanning acquisitive to conservative strategies and tested whether tree species functional strategies influenced tree leaf elemental concentrations after the fertilization. Leaf N:P ratios showed considerable differences among co‐occurring species. Overall, we found that soil N addition treatments increased leaf N concentration, although leaf N:P ratios were not affected. Changes in leaf Al, Fe and S concentrations were correlated with species functional strategy: conservative species showed a greater increase in leaf Fe compared with acquisitive species, whereas acquisitive species showed a greater increase in leaf Al but a decrease in leaf S compared with conservative species. Synthesis. We show that soil elements uptake differs between acquisitive and conservative species and that acquisitive species may not take up soil elemental resources more effectively than conservative species. We suggest that the greater Fe acquisition by conservative species, in comparison to acquisitive species, might be due to a stress tolerance strategy. The overall increase in leaf N showed that, in this nutrient‐poor forest, N is a fundamental requirement irrespective of species functional strategies. Given the increased leaf Al and Fe concentration after liming, we also suggest that these elements are important, and possibly limiting (Fe), in this heath forest.

Distribution of Proboscis Monkeys (Nasalis Larvatus Wurmb, 1787) in Forest Fragmentation Area, Tunan River, Waru District, East Kalimantan, Indonesia

The proboscis monkey (Nasalis larvatus Wurmb, 1787) is an endemic primate of the island of Borneo that is protected and threatened with extinction. Deforestation is the biggest threat to proboscis monkeys because it destroys the ideal habitat for proboscis monkeys. The proboscis monkey’s habitat includes various types of forest such as wetland forest, peat forest, heath forest, rubber forest, and mangrove forest associated with water. The Tunan River is one of the proboscis monkey’s habitats outside the conservation area in the form of a forest that is fragmented apart by roads, residential areas, plantations, and ponds. Meanwhile, the spread of proboscis monkeys in the Tunan river forest fragmentation area, Waru District, North Penajam Paser Regency, East Kalimantan has never been reported so that a study is needed to determine its distribution. This research was started from January to February 2022. The data was collected using the boat survey method, namely observation by using a boat. The results obtained were twenty-four proboscis monkey distribution points based on direct observation. The distribution pattern of proboscis monkeys tends to be random in the fragmentation area and is found more in the upstream than downstream areas due to habitat conditions and the presence of forage trees that support the proboscis monkey population. Therefore, to preserve the proboscis monkey, it is necessary to provide information to the surrounding community by protecting the proboscis monkey habitat

Floristic composition and species diversity in three habitat types of heath forest in Belitung Island, Indonesia

Oktavia D, Pratiwi SD, Munawaroh S, Hikmat A, Hilwan I. 2021. Floristic composition and species diversity in three habitat types of heath forest in Belitung Island, Indonesia. Biodiversitas 22: 5555-5563. Exploring plant diversity, structure, and composition of vegetation in forest ecosystems is necessary for understanding the mechanism of species coexistence and forest dynamics, moreover in a unique and vulnerable ecosystem such as tropical heath forest (kerangas). We investigated the composition and structure of vegetation of heath forests in East Belitung, Indonesia in three habitat types, namely primary heath forest (rimba), secondary heath forest (bebak), and grassland (padang). Vegetation analysis was conducted using the combination of transect and plot method to calculate the importance value index (IVI) for all species and biodiversity indicators for each habitat type. We recorded 157, 135, and 31 species in rimba, bebak, and padang, respectively. The top three dominant families of species found were Myrtaceae, Clusiaceae, and Euphorbiaceae. In rimba, Syzygium lepidocarpa had the highest IVI for seedlings, Calophyllum lanigerum had the highest IVI for saplings, and Schima walichii had the highest IVI for trees. In bebak, Guioa pleuropteris had the highest IVI for seedlings, Garcinia hombroniana had the highest IVI for saplings, and Schima walichii had the highest IVI for trees. In padang, Fimbristylis sp. had the highest IVI for seedlings, while Leptospermum flavescens had the highest IVI for saplings and trees. Some pioneer species were found such as Rhodomyrtus tomentosa, Rhodamnia cinerea, Syzygium buxifolium. We also found two carnivorous plants Drosera burmannii and Nepenthes gracilis in padang, indicating that this habitat type is poor in nutrients in the soils. We suggested that the presence of species composition in the three habitat types of heath forest is an essential plant resource to be conserved and sustainably utilized. Establishing reserve areas to protect natural habitat and biodiversity is encouraged to provide proper ecosystem function for the people and nature.

Comparative leaf anatomy of ten Nepenthes L. species (Nepenthaceae) from Peninsular Malaysia

The genus Nepenthes (Nepenthaceae) in Peninsular Malaysia includes fourteen species that can be found from the sea-level to over 1000 m in the mountains. Our observation indicated that Nepenthes can be found in five major habitat types: specifically in tropical lowland evergreen rain forest, heath forest, peat swamp forest, montane forest, and limestone forest. Their leaves have several anatomical characters that remain underexplored. There were specific differences between species that could be potential identification characters. The following anatomical characteristics were explored for their diagnostic value and comprised of ten distinct anatomical characteristics in Nepenthes, viz., density and stomatal index (SI), hypodermis cell – cell layers, occurrence of fiber groups mixed with the hypodermis cells, adaxial cuticle thickness, vascular bundle arrangement, midrib outline shape, venation plasticity, druses appearance and appendage/trichome type.

Habitat association and population size of the Madeira Firecrest (Regulus madeirensis)

Basic population information is often lacking for recently recognized species, yet such information is essential for conservation and management. This study provides a detailed assessment of population size and habitat association in the Madeira Firecrest (Regulus madeirensis). Species abundance and habitat data were collected using a point transect distance sampling method. Estimates of density per habitat type were made, in conjunction with presence and absence data derived from the Madeira bird atlas, to estimate population size and habitat associations. We estimate the population size of the Madeira Firecrest to be 698,300 (95% CI: 523,540–869,960), which greatly exceeds the 10,000 individuals threshold for the IUCN “Vulnerable” category. Distribution and abundance were strongly associated with laurel and heath forest, with 56% of the population found in these 2 habitats. Historically, much of the native laurel and heath forest was lost on Madeira, but these remnant native forest habitats are now protected. Based on the large population size and successful management of the laurel forest habitat, our results suggest there is no immediate risk of a change in conservation status for the Madeira Firecrest.

Habitat association and population size of the Madeira Firecrest (Regulus madeirensis)

Basic population information is often lacking for recently recognized species, yet such information is essential for conservation and management. This study provides a detailed assessment of population size and habitat association in the Madeira Firecrest (Regulus madeirensis). Species abundance and habitat data were collected using a point transect distance sampling method. Estimates of density per habitat type were made, in conjunction with presence and absence data derived from the Madeira bird atlas, to estimate population size and habitat associations. We estimate the population size of the Madeira Firecrest to be 698,300 (95% CI: 523,540–869,960), which greatly exceeds the 10,000 individuals threshold for the IUCN “Vulnerable” category. Distribution and abundance were strongly associated with laurel and heath forest, with 56% of the population found in these 2 habitats. Historically, much of the native laurel and heath forest was lost on Madeira, but these remnant native forest habitats are now protected. Based on the large population size and successful management of the laurel forest habitat, our results suggest there is no immediate risk of a change in conservation status for the Madeira Firecrest.

Impacts of invasive Acacias on ion deposition in a coastal Bornean tropical heath forest

ABSTRACT The uncontrolled invasive spread of exotic Acacias is a growing concern for many tropical ecosystems, particularly due to their negative impact upon nutrient cycling. Studies investigating the effects of Acacia invasion on nutrient cycling have focused on litterfall and litter decomposition, although its impact on ion deposition in tropical ecosystems is less understood. We quantified and compared the rates of ion deposition (Ca2+, Mg2+, NH4 +, NO3 −) between Acacia-invaded and non-invaded tropical heath (Kerangas) forest sites in Brunei Darussalam, Southeast Asia. Ion exchange resin (IER) sampler, IER ring and IER bags were used to determine ion depositions via throughfall, in soils and in stream water respectively. Throughfall in Acacia-invaded heath forest sites recorded significantly higher NH4 + and Ca2+ depositions but lower Mg2+ than non-invaded, intact sites. For ion deposition in soil, all depths recorded significantly higher Ca2+ (except for 0 cm depth), Mg2+ and NH4 + depositions, but significantly lower NO3 − depositions, in Acacia-invaded sites. Ion deposition in stream water showed significant monthly variations, with Acacia-invaded sites recording significantly higher Mg2+ depositions in June, August and September 2015 but lower NH4 + depositions in June, July and September, lower NO3 − and Ca2+ depositions in June and September than non-invaded heath forest sites. Overall, these findings demonstrate that ion deposition via throughfall, in soil and in stream water were all affected by Acacia invasion, thus confirming the influence of alien invasive Acacias on nutrient cycling of tropical heath forests.

Identification of Bird species in Wetlands around Siran Lake, Muara Kaman, Central Mahakam, East Kalimantan

The avifauna of tropical peat swamp forests in East Kalimantan has not been well documented because of the smallest peat area compared to central Kalimantan. The surveys were conducted using various methods in the Muara Siran peat swamp forests and surrounding areas of Lake Siran (heath forest and riparian) in East Kalimantan, Indonesia. These findings were recorded on a list of 80 bird species as well as in numerous noteworthy records. Wetlands are an essential habitat for many threatened and near-threatened bird species. We also discovered Gallinula tenebrosa in Siran Lake, a species that has not been seen in over a century. However, it has a wide distribution globally, including in Australia and the United States. In the peat swamp forest, we recorded Cymbirrhinchus macrurus and Ichtyophaga humilis, rare and widely distributed. We also found Dicrurus hottentotus and Dicrurus remifer, some species of Ferruginous Babbler, Trichastoma bicolor, and the White-necked Babbler, Stachyris leucotis. The Hook-billed bulbul Setornis criniger and the Sooty capped Babbler Malacopteron affinae are found in riparian forests. There are six species of woodpecker. Dryocopus javensis, Great Slaty Woodpecker, Mulleripicus pulverulentus, Meyglyptes tukki, Picus puniceus, and Sasia abnormis. Cuckoo-shrike Coracina striata and Pitta sordia were also discovered. Wetlands (peat swamp forest, heath forest, and riparian areas) should be better protected due to their importance to many species, particularly from destruction and loss of habitat caused by forest fires.

Age-dependence of stand biomass in managed boreal forests based on the Finnish National Forest Inventory data

Information on carbon stocks and the rate of carbon accumulation is needed to harness the climate change mitigation potential of boreal forests. While previous studies have revealed general patterns and mechanisms for age-dependence of stand biomass, simple stand-level models that address the age-biomass relationship on average in managed boreal forests in different environmental conditions are largely missing. We developed models for the relationship between stand age and biomass by forest types on peatlands and mineral soils across climate zones in managed forests in Finland based on National Forest Inventory measurements from 1996 to 2018. In addition, we analyzed at which rate biomass accumulates when managed forest ages in different growth conditions. In northern Finland the maximum biomass change rate was one third, and the maximum biomass stock less than half of the corresponding values in sub-xeric heath forests on minerals soils in southern Finland. On drained peatlands the maximum biomass growth rate was approximately half, and on undrained peatlands one third of the maximum growth rate on mineral soils. On most fertile sites on mineral soils the maximum biomasses were three times larger than on the poorest sites. Correspondingly, the maximum biomass stock change rates were almost eight times faster on most fertile sites. In the example cases presented, the highest annual biomass change rates were achieved in young forests on average at the stand ages of 7–32 years, whereas the 95% of the maximum stock were reached on average in stands of 63–147 years. At the age of highest biomass growth rate stands contained 27–59% of the maximum biomass stocks. The developed models can be used in practical applications such as accounting of biogenic carbon in life-cycle assessments, mapping carbon, or creating simple predictions of biomass stock development in regions, or estimating the mitigation potential of afforestation and reforestation or estimating the magnitude of carbon offsets projects.

Effects of El Niño drought on tree mortality and growth across forest types at different elevations in Borneo

The 2015–2016 El Niño drought had a strong impact on tropical forest tree dynamics in Borneo. To assess the effects of the drought on trees growing in different environments, we examined differences in tree mortality and growth before and during the drought at two elevations (ca. 500 m vs. 1000 m a.s.l.) and among forest types (mainly heath forest on sandy soils and mixed dipterocarp forest) in Sabah, Borneo. We hypothesized that the effects of the drought on trees would be greater at low elevation than at high elevation, and in mixed dipterocarp forest than in heath forest, since tree species in heath forest are likely to adapt to stressful conditions.Tree mortality in heath and mixed dipterocarp forests was higher during the drought than before the drought. In addition, tree mortality was markedly higher at low elevation than at high elevation in both forest types. There was no significant interaction between drought and elevation, indicating that the drought and elevation independently affected tree mortality. Contrary to our expectation, at low elevation, heath forest trees showed comparable or higher mortality than mixed dipterocarp forest trees. Moreover, diameter and basal area growth rates were higher during the drought than before, particularly at low elevation, probably owing to the improved light conditions for surviving trees after the death of surrounding trees. Species-level wood density did not significantly affect tree mortality in our sites. Species mean stem growth rates before the drought negatively affected tree mortality, suggesting that species with higher tree mortality had reduced stem growth prior to the severe drought period.Our results show that the El Niño-induced drought increased mortality and growth of heath forest trees on sandy soils as well as in mixed dipterocarp forest trees. The results also suggest that markedly high tree mortality at low elevation was caused by the additive effect of drought and elevation.

Carbon stock potential on various land covers in heath forest in Liang Anggang, South Kalimantan

Heath forest serves as a large carbon and water storage. This study aims to obtain information on carbon storage potential of each carbon component in heat forest in Liang Anggang Protection Forest. Data collection was carried out on six types of land cover, namely: agricultural land, barren land/settlement, scrub, peat soil, and forest. The carbon components were measured such as trees, undergrowth, litter, necromass, and soil. Measurement plots were established with size of 40 x 100 m for trees and necromasses > 30 cm in size, and sub-plots measuring 5 x 40 m for trees with a diameter of 5–30 cm as many as 5 plots for each type of land cover. The understorey and litter components used a plot with size of 0.5 x 0.5 m. In tree pools, carbon stock was determined by indirect measured with alometric model, while the other was used by direct measurenment. The results showed that carbon in the soil contributed the largest potential carbon storage (> 95%) of the total carbon storage in all land cover types. The pattern of the proportion of carbon storage in this forest type was similar to the peat swamp forest type. On heat forest, carbon stock potential on scrub was 318.8 Mg/Ha and the potential of heat forest type was the lowest (256.8 Mg/Ha ). In total, the average carbon storage potential was 285.01 ± 48.78 Mg/Ha. The carbon storage at this location reached 2.99 x 105 tons of carbon, or equivalent to carbon absorption of 1,10 X 106 CO2 e ton CO2e. The large amount of carbon storage in heath forest in the study area has the potential to support diversification and optimization of land use through a carbon trading scheme. Key words: trade, agriculture, proportion, scheme, soil