Gunung Leuser National Park (NP) is the biggest NP in North Sumatra. Though very few plant ecological studies were conducted there. Most studies in Gunung Leuser NP are related with protected animals, such as Sumatran Tiger, Elephant or... more
Gunung Leuser National Park (NP) is the biggest NP in North Sumatra. Though very few plant ecological studies were conducted there. Most studies in Gunung Leuser NP are related with protected animals, such as Sumatran Tiger, Elephant or Orang Utan. Thus, the aim of this preliminary study is to understand the plant structure and composition in the tropical forest of Gunung Leuser National Park. A 0.5-ha plot was established near Gua Kambing, Tangkahan area in November 2015. All tree species bigger than 15 cm girth were recorded, measured, and identified. The dominant species were from Dipterocarpaceae, followed by Myrtaceae and Achariaceae. The total number of trees was 693 trees or 1,386 trees/ha with the total Basal area was 42.9m2/ha and the biggest diameter was 147cm. The results from diversity index analysis ((H’=4.43; D=0.97; α=75) confirm that the forest area had a relatively high diversity, with Agrostistachis sessilifolia dominates the understory layer. The Gua Kambing area had relatively high plant diversity, less disturbance, and bigger trees than other studied areas in tropical Indonesian forests in Sumatra.
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Research Interests:
Ecosystems are under the control of negative feedback due to resource competition, and it is difficult to explain the coexistence of many species in an ecosystem. By contrast, evolutionary history suggests that positive feedback between... more
Ecosystems are under the control of negative feedback due to resource competition, and it is difficult to explain the coexistence of many species in an ecosystem. By contrast, evolutionary history suggests that positive feedback between living organisms and environments contributes to increasing biodiversity. This paper presents a conceptual framework to interface these feedbacks, taking forests and tree communities as an example. One of the prevailing global patterns of biodiversity is the latitudinal gradient of tree species diversity in forests. A tenfold difference exists in species diversity between tropical lowland forests and either tropical high-altitude forests or temperate forests. We examined tree census data from permanent plots across various forest types in eastern Asia. Tree species diversity increased exponentially along a geographic gradient while ecosystem measures such as biomass, biomass turnover rate and asymptotic canopy height increased only linearly. Examination of a size-structure-based dynamic model of tree populations suggests that these ecosystem measures multiplicatively contribute to the extreme species diversity in tropical lowland rain forests. The same model also shows that any singular species with higher resource-use efficiency replaces all coexisting species under the constraint of functional tradeoff. Such replacement brings about increasing efficiency of ecosystems in resource exploitation, and in turn presents a greater opportunity for species coexistence. The non-linear relationship between whole ecosystem measures and species diversity develops through the process of positive feedback between the energetic efficiency of ecosystems and the functional differentiation among species, on evolutionary time scales.
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Despite their fundamental importance the links between forest productivity, diversity and climate remain contentious. We consider whether variation in productivity across climates reflects adjustment among tree species and individuals, or... more
Despite their fundamental importance the links between forest productivity, diversity and climate remain contentious. We consider whether variation in productivity across climates reflects adjustment among tree species and individuals, or changes in tree community structure. We analysed data from 60 plots of humid old-growth forests spanning mean annual temperatures (MAT) from 2.0 to 26.6 °C. Comparing forests at equivalent aboveground biomass (160 Mg C ha–1), tropical forests ≥24 °C MAT averaged more than double the aboveground woody productivity of forests <12 °C (3.7 ± 0.3 versus 1.6 ± 0.1 Mg C ha–1 yr–1). Nonetheless, species with similar standing biomass and maximum stature had similar productivity across plots regardless of temperature. We find that differences in the relative contribution of smaller- and larger-biomass species explained 86% of the observed productivity differences. Species-rich tropical forests are more productive than other forests due to the high relativ...
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This data paper presents the vascular plant biodiversity sampled from four plots on Amami‐Oshima Island, three plots on Tokunoshima Island, and one plot on Okinawa Island within the natural World Heritage site, and an additional three... more
This data paper presents the vascular plant biodiversity sampled from four plots on Amami‐Oshima Island, three plots on Tokunoshima Island, and one plot on Okinawa Island within the natural World Heritage site, and an additional three plots in southern Kyushu using the standardized belt‐transect survey method during July 2012 to October 2020. The dataset includes 99 families, 215 genera, and 381 species of vascular plants, and provides species occurrence among 10 subplots for all vascular plants, girth at breast height (GBH) and height of all trees and climbers with GBH ≥ 3.2 cm or height ≥ 4 m in each 5 × 100 m plot. This dataset serves as baseline data for subsequent plant diversity monitoring of the natural World Heritage site. The Darwin Core Archive is deposited in the Global Biodiversity Information Facility (GBIF) through the Japan Initiative for Biodiversity Information, and are thus accessible through the GBIF portal under the Creative Commons Attribution 4.0 International ...
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The research of decomposition rate ofAltingia excelsaNoroña, Schima wallichii(D.C.) Korth., Castanopsis acuminatissima(Bl.) A. DC., C. javanica(Bl.) A. DC., andQuercus lineataBlume was carried out in the low montane forest in Gunung... more
The research of decomposition rate ofAltingia excelsaNoroña, Schima wallichii(D.C.) Korth., Castanopsis acuminatissima(Bl.) A. DC., C. javanica(Bl.) A. DC., andQuercus lineataBlume was carried out in the low montane forest in Gunung Halimun Salak National Park, West Java. The aim of the research was to examine the decomposition rate of dominant species and their role in the nutrient cycling. The decomposition rate of those dominant species was carried out by using the litterbag methods. The highest decomposition rate was observed forQ. lineatafollowed byC. javanica,C. acuminatissima,S. wallichii,A. excelsaand the mixed litter in Cikaniki research station. Meanwhile, in the Wates plot, the highest rate was observed forC. acuminatissimafollowed byC. javanica,Q. lineata,S. wallichii,A. excelsaand the mixed litter. This research shows thatC. acuminatissimadecomposed faster compared to other dominant species due to their litter quality combination of high nitrogen and low lignin content....
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Six pteridophyte species of five families and 12 spermatophyte species of 10 families are reported from Bolaven Plateau, southern Laos, as new records to the flora of Laos. Moreover, two new species, Sterculia bolavenensis (Malvaceae) and... more
Six pteridophyte species of five families and 12 spermatophyte species of 10 families are reported from Bolaven Plateau, southern Laos, as new records to the flora of Laos. Moreover, two new species, Sterculia bolavenensis (Malvaceae) and Wikstroemia bolavenensis (Thymelaeaceae), are described. For each species, voucher specimens are cited, photographs are shown and additional information including geographical distribution, ecology and taxonomic notes are provided.
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Research Interests:
Corridor area of Gunung Halimun Salak National Park was degraded and fragmented by human activities. However, little is known about recovery process in tropical degraded forest under different land use history. To clarifyvegetation... more
Corridor area of Gunung Halimun Salak National Park was degraded and fragmented by human activities. However, little is known about recovery process in tropical degraded forest under different land use history. To clarifyvegetation structure and forest recovery related to land use history we placed 22 plots (11 of 10 x 10 m2 in abandoned plantation and 11 of 20 x 20 m2 in secondary forest, respectively). DCA (Detrended correspondence analysis) discriminated the plots into three community groups. Swieteniamacrophylla –Agathisdammaa community in abandoned plantation where had a land use history of clear felling.Maesopsiseminii–Cyathea spp. community had a history of severe human disturbance. Fagaceae-Schimawallichii was in less disturbed forest. Below the plantation canopy, light tolerant species, weeds, grasses, and fern of Dicranopteris linearis were dominant. Some exotic plants spread to the disturbed forest. The less disturbed forest in distant area from village remained in good c...
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Ecosystems are under the control of negative feedback due to resource competition, and it is difficult to explain the coexistence of many species in an ecosystem. By contrast, evolutionary history suggests that positive feedback between... more
Ecosystems are under the control of negative feedback due to resource competition, and it is difficult to explain the coexistence of many species in an ecosystem. By contrast, evolutionary history suggests that positive feedback between living organisms and environments contributes to increasing biodiversity. This paper presents a conceptual framework to interface these feedbacks, taking forests and tree communities as an example. One of the prevailing global patterns of biodiversity is the latitudinal gradient of tree species diversity in forests. A tenfold difference exists in species diversity between tropical lowland forests and either tropical high-altitude forests or temperate forests. We examined tree census data from permanent plots across various forest types in eastern Asia. Tree species diversity increased exponentially along a geographic gradient while ecosystem measures such as biomass, biomass turnover rate and asymptotic canopy height increased only linearly. Examination of a size-structure-based dynamic model of tree populations suggests that these ecosystem measures multiplicatively contribute to the extreme species diversity in tropical lowland rain forests. The same model also shows that any singular species with higher resource-use efficiency replaces all coexisting species under the constraint of functional tradeoff. Such replacement brings about increasing efficiency of ecosystems in resource exploitation, and in turn presents a greater opportunity for species coexistence. The non-linear relationship between whole ecosystem measures and species diversity develops through the process of positive feedback between the energetic efficiency of ecosystems and the functional differentiation among species, on evolutionary time scales.
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The marked biogeographic difference between western (Malay Peninsula and Sumatra) and eastern (Borneo) Sundaland is surprising given the long time that these areas have formed a single landmass. A dispersal barrier in the form of a dry... more
The marked biogeographic difference between western (Malay Peninsula and Sumatra) and eastern (Borneo) Sundaland is surprising given the long time that these areas have formed a single landmass. A dispersal barrier in the form of a dry savanna corridor during glacial maxima has been proposed to explain this disparity. However, the short duration of these dry savanna conditions make it an unlikely sole cause for the biogeographic pattern. An additional explanation might be related to the coarse sandy soils of central Sundaland. To test these two nonexclusive hypotheses, we performed a floristic cluster analysis based on 111 tree inventories from Peninsular Malaysia, Sumatra, and Borneo. We then identified the indicator genera for clusters that crossed the central Sundaland biogeographic boundary and those that did not cross and tested whether drought and coarse-soil tolerance of the indicator genera differed between them. We found 11 terminal floristic clusters, 10 occurring in Borne...
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ABSTRACTAim Tropical forests have been recognized as important global carbon sinks and sources. However, many uncertainties about the spatial distribution of live tree above‐ground biomass (AGB) remain, mostly due to limited availability... more
ABSTRACTAim Tropical forests have been recognized as important global carbon sinks and sources. However, many uncertainties about the spatial distribution of live tree above‐ground biomass (AGB) remain, mostly due to limited availability of AGB field data. Recent studies in the Amazon have already shown the importance of large sample size for accurate AGB gradient analysis. Here we use a large stem density, basal area, community wood density and AGB dataset to study and explain their spatial patterns in an Asian tropical forest.Location Borneo, Southeast Asia.Methods We combined stem density, basal area, community wood density and AGB data from 83 locations in Borneo with an environmental database containing elevation, climate and soil variables. The Akaike information criterion was used to select models and environmental variables that best explained the observed values of stem density, basal area, community wood density and AGB. These models were used to extrapolate these param...
Research Interests: Environmental Science, Carbon, Biomass, Ecology, Density, and 15 moreBiogeography, Biodiversity, Tropical forest, Carbon Capture and Storage, STEM, Carbon Storage, Tree, Density gradient, Storage, Global Ecology, Ecological Applications, Biodiversity In Borneo, Environment, Amazonian, and Basal Area
Research Interests: Geography, Environmental Science, Diversity, Phylogenetics, Ecology, and 13 moreBiodiversity, Biological Sciences, Tropical trees, Seasonality, Environmental Sciences, Soil Carbon, Borneo, Species Richness, Meta Analysis, Spatial Distribution, Spatial Variation, Soil Texture, and Distribution Pattern
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Vegetation types in fresh water swampy areas: Mandor in West Kalimantan and Lahei in Central Kalimantan, were compared.There were three types: kerangas, kerangas shrub and peat swamp forest. Kerangas forests in both areas had similar... more
Vegetation types in fresh water swampy areas: Mandor in West Kalimantan and Lahei in Central Kalimantan, were compared.There were three types: kerangas, kerangas shrub and peat swamp forest. Kerangas forests in both areas had similar flora in some extent.That of peat swamp was very different from kerangas though both vegetations distributed in adjacent area.
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Research Interests:
The high species richness of tropical forests has long been recognized, yet there remains substantial uncertainty regarding the actual number of tropical tree species. Using a pantropical tree inventory database from closed canopy... more
The high species richness of tropical forests has long been recognized, yet there remains substantial uncertainty regarding the actual number of tropical tree species. Using a pantropical tree inventory database from closed canopy forests, consisting of 657,630 trees belonging to 11,371 species, we use a fitted value of…
Research Interests: Nonparametric Statistics, Phylogeography, Biology, Ecology, Biodiversity, and 15 moreMedicine, Multidisciplinary, Tropics, Forests, Global Biodiversity, Rainforest, Trees, Species Richness, Plant Community Ecology, Ecosystem, Conservation of Natural Resources, Species Specificity, Tropical Climate, Temperate Climate, and diversity estimation
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Research Interests:
Page 1. Biodivers Conserv (2008) 17:523538 DOI 10.1007/s10531-007-9268-1 1 C ORIGINAL PAPER Species diversity, abundance, and vertical size structure of rattans in Borneo and Java Natsuki M. Watanabe · Eizi Suzuki ...