MUSTAQIM, W. A., HUTABARAT, P. W. K., PUTERA, A. K. S., BANDJOLU, K. P., AHMAD, R. P. P. & YUDISTIRA, Y. R. 2026. Bulbophyllum alsiosum (Orchidaceae): a new record from Sulawesi, Indonesia. Reinwardtia 25(1): 41‒47. — Bulbophyllum alsiosum Ames, a previously Philippines endemic, is reported for the first time in Sulawesi and also represents the first country record for Indonesia. The species was collected from three localities in the montane forest of central and the upper montane forest of the southwestern part of the island. The finding increases the number of Bulbophyllum sect. Beccariana in Sulawesi to nine species. Description, note, preliminary conservation status, and photographs are given.
REZEKIAH, A. A., FITHRIA, A., YAMANI, A., ROSIDAH, RUDY, G. S., ALI, S. D. & SHIBA, Y. N. 2026. Carbon stock and carbon economic value of forest ecosystem in the Suwangi Island Nature Park, Tanah Bumbu Regency, South Kalimantan, Indonesia. Reinwardtia 25(1): 1‒11. — The forests on Suwangi Island are currently facing significant challenges arising from human activities, land degradation, and potential land-use conflicts, all of which critically undermine their capacity to absorb and store carbon. The purpose of this study was to analyze the carbon stock value and economic value of carbon stored in Suwangi Island Nature Park. The allometric method was employed to calculate carbon stocks, with sampling locations determined using purposive sampling. The carbon stock results were subsequently converted to estimate the economic value of carbon. The land cover types identified in Suwangi Island Nature Park include primary forest, secondary forest, plantation, medium-density mangrove forest, and high-density mangrove forest. The analysis revealed that the highest biomass was stored in the primary forest and the lowest in the medium-density mangrove forest. The total carbon that can be stored at the research site is 80,45554667 tons/ha, and the resulting carbon economic value is IDR 2,851,347,872.68. These findings highlight the significant variation in carbon storage across different land cover types and underscore the critical role of primary forests as major carbon sinks. The novelty of this study lies in the integration of spatial (ArcGIS), ecological (allometric), and economic approaches within a single analytical framework, which remains rarely applied. The practical implications of this research emphasize the importance of management strategies based on carbon economic valuation and the potential utilization of carbon trading schemes, such as REDD+, to enhance conservation incentives and ensure the sustainability of Suwangi Island Nature Park management.
SUSANTI, R., GIRMANSYAH, D., PRATAMA, B. A. & JAKALELANA, S. 2026. Tree species composition of the lowland forest in Bukit Baka Bukit Raya National Park, East Kalimantan, Indonesia. Reinwardtia 25(1): 31‒40. — Tree species diversity and structural characteristics in the lowland forest of Bukit Baka Bukit Raya National Park (TNBBBR) were examined to assess the overall floristic diversity of this conservation area. A survey was conducted at the national park boundary with PT. Sari Bumi Kusuma, a forest company concession in East Kalimantan. Data were collected using transect plots of 50 × 10 m at 100 m elevation intervals across three locations (Km. 37, Km. 39a, and Km. 39b), for a total of eight plots. All trees with a diameter at breast height (DBH) ≥ 10 cm were measured and identified. We recorded 352 trees inside the plots, representing 138 species and 35 families, with a total basal area of 24.7 m2/0.4ha. The dominant families in terms of basal area are Dipterocarpaceae and Myrtaceae. We found 79 Dipterocarpaceae trees, representing 22.4% of individuals, in the surveyed area. In terms of species richness, Dipterocarpaceae composed 21% of the species. There were seven genera (Dipterocarpus, Dryobalanops, Hopea, Shorea, Rubroshorea, Richetia, and Anthoshorea) and 29 species. Shorea was the richest genus among them. Shorea laevis, Rubroshorea leprosula, and R. dasyphylla were the most common species found in Dipterocarpaceae.
AULIA, S. A. Z., MULYANTO, D., ISKANDAR, B. S. & ISKANDAR, J. 2026. Exotic wild plants, cultural adaptation, and local food diversity in tea estate’s buffer-village (West Java, Indonesia): an ethnobotanical analysis. Reinwardtia 25(1): 13‒29. — This research examines the ethnobotanical knowledge of exotic wild plants utilized as complementary food in Tegallega hamlet, a part of the buffer village adjacent to a historic tea estate in West Java, Indonesia. Through semi-structured interviews and field surveys with 22 local informants, 42 exotic wild plants from 22 families were recorded, primarily from Asteraceae and Solanaceae. Predominant species were herbaceous neophytes introduced during or after European colonization, illustrating the historical impact of the Columbian Exchange and plantation practices. Leaves were the most commonly used plant part, frequently consumed as lalapan, an essential ingredient of Sunda cuisine. The community emphasizes readily accessible resources that require the least effort, consistent with optimal foraging theory, whereas gender roles markedly affect foraging practices—women generally collect plants near villages, whereas men tend to explore farther into the forest. The incorporation of these exotic wild plants into local diets underscores cultural adaptation and the enhancement of local knowledge. Using exotic wild plants sparingly can enhance conservation of native and endemic species, lessen the negative effects of invasive species, and create opportunities for ecotourism growth. This study highlights the interaction of historical, ecological, and cultural factors that influence local plant utilization practices.
Version 2 Note: This article was updated on 29 June 2026 to correct an omission where Angga Irfandi Yudistira as a co-author was left out of the Indonesian abstract. The author has now been added to the official author list following approval from all original authors and the editorial board. Check the updated Galley PDF RISNA, R. A., LUGHADHA, E. N., PRASETYO, L. B., SUTOMO, AIDI, M. N., BUCHORI, D., PLUMMER, J., LATIFAH, D., YUSWANDI, A. Y. & YUDISTIRA, A. I. 2026. Climate-driven range shifts threaten keystone endemic figs of Java: complementing IUCN Red List assessment with species distribution modelling to guide conservation priorities. Reinwardtia 25(1): 49‒63. — This study evaluates the extinction risk and climate-driven habitat dynamics of two endemic figs of Java, Ficus trachycoma Miq. and F. miqueliana C.C.Berg. Both species are poorly known, with no confirmed field records for more than six decades. Conservation status was assessed under IUCN Red List criteria, with extent of occurrence (EOO) and area of occupancy (AOO) calculated using validated herbarium records. Ficus trachycoma is restricted to a single 19th-century locality, with an EOO and AOO of 4 km², a single known location, and continuing decline in habitat, qualifying it as Critically Endangered. Ficus miqueliana has been more widely recorded, with an AOO of 20 km² and an EOO of about 600 km², ≤5 locations, and continuing decline in habitat, meeting the thresholds for Endangered. Species distribution modelling using MaxEnt and CMIP6 climate projections (SSP2-4.5 and SSP5-8.5) was applied to predict current and future habitat suitability. The models performed with high accuracy (AUC = 0.912‒0.935, TSS = 1.0) and identified slope (52–73% contribution), temperature seasonality, and precipitation in the wettest, warmest, and coldest quarters as key predictors of occurrence. Ficus miqueliana’s current suitable habitat is 16,233 km² (12.4% of Java) in fragmented lowland and foothill forests. CMIP6 projections (MIROC6, SSP2-4.5/SSP5-8.5 for 2050s and 2090s) forecast net contractions with upslope shifts: mid-century losses of 9–11% in Java, late-century persistence in montane refugia under moderate emissions but severe fragmentation under high emissions. These findings demonstrate that both endemic figs are highly vulnerable to environmental change. Applying IUCN Red List assessments alongside species distribution modelling provides a replicable framework for evaluating extinction risk in data-limited species and identifies priority areas for climate-adaptive conservation planning on Java.
