Jurnal Manajemen Hutan Tropika

Species Distribution Model and Conservation of Mentaok (Wrightia javanica) in Indonesia

Sutomo — 2025-01-24

The Alas Mentaok was a forest dominated by the mentaok tree (Wrightia javanica) that once existed in Yogyakarta, Java Island, Indonesia. This forest has cultural and historical value, as it is believed to be the first location to establish the Mataram Islam Kingdom in Java in 1582 AD. This study utilized species distribution models (SDMs) to investigate the species distribution pattern and assess its latest conservation status in Java and the Lesser Sunda Islands, Indonesia. The methodology used involved collecting occurrence and environmental data of W. javanica, conducting species distribution modeling using the maximum entropy algorithm, evaluating the model's accuracy, and performing an independent assessment of the area of occupancy (AOO) and extensive occurrence (EOO) using the geospatial conservation assessment tool (GeoCAT). While the number of suitable habitat areas for W. javanica in Yogyakarta is projected to decrease by 2100, the islands of Sumba and Timor are anticipated to experience an increase in the suitable habitat areas for the species during the same year. The analysis of BIOCLIM 34 indicates the mean moisture index of the warmest quarter plays a vital role in the current and future projections. AOO calculation in GeoCAT places this species in the endangered (EN) category, particularly within our regions of interest in Java and the Lesser Sunda Islands. Overall, a full assessment combining a habitat suitability model with current conservation status information would provide a more comprehensive understanding of mentaok's habitat preferences and current conservation status in Indonesia.

Effect of Pandemic COVID-19 on Tropical Forest Cover in Small Island: Case Mansinam Island Papua using Google Earth Imagery

Francine Hematang — 2025-01-24

Covid-19 became a global pandemic in 2020 and has multiple impacts on the economy, social, culture, food systems, and also the environment, especially on tropical forest cover in small island. This study aims to determine the impact of the Covid-19 pandemic on the forest cover of small populated islands. Using remote sensing and geographic information system technology based on high-resolution satellite imagery from google earth imagery, land cover was observed in 2018, 2020, and 2023. This study found that during the 2020 pandemic, tropical forest cover on small populated islands has decreased. Mansinam's forest cover decreased by 4.3%, bare land increased by 80.6%, agricultural land increased by 75.3%, and shrubs increased by 54.9%. Another important finding is that 78.9% of the total deforestation was due to forest conversion to bare land and agricultural land. Land and forest utilization on small islands will increase when accessibility is limited, especially during the pandemic. Future studies will be on the structure and composition of species in locations that experienced deforestation during the pandemic and detailed studies related to changes in the occupations of Mansinam people due to the pandemic that have a relationship with forests.

Avicennia alba, an Additional Potential Carbon Sequester in Mangrove Ecosystems

Nur Hasyimah Ramli — 2025-01-24

Mangrove forests have exceptional carbon sequestration capacity for mitigating climate change impacts. Increased atmospheric CO₂ can accelerate crops growth, improves water-use efficiency, and disrupt soil-plant balance. The performance of Avicennia alba in terms of morphometrics and biomass under environmental stresses such as elevated CO₂ was poorly understood. Thus, this study aims to determine the growth response and survivability of A. alba by examining height, leaf number, and growth rate under elevated CO₂ from the early stages of development. A number of 120 seed samples of A. alba was divided into two groups; 60 germinated seeds placed in a CO₂ incubator and 60 in a shade house as control. The growth rate, plant height, leaf number, and mortality were compared between the two groups and statistical analyses were conducted. Increased concentrations of CO₂ enhance the development and survival of seedlings by promoting greater photosynthesis and more effective water use. The decrease in leaf production is most likely due to a shift in resource allocation, where plants prioritize the accumulation of total biomass over leaf formation. An understanding of this trade-off elucidates the potential response of plants to increasing CO₂ levels in climate change scenarios.

Non-timber Forest Products in Bu Gia Map: Local Use and Sustainable Management

Thanh Sang Dinh — 2025-01-24

Non-timber forest products (NTFPs) in Bu Gia Map National Park (BGMNP) have played a critical role in local livelihood. Thus, the park resources have been threatened by local harvesting. Yet, the local perspective of the NTFP utilization between indigenous ethnic minorities (IMs) and Kinh peoples (KPs) has been poorly understood. Besides, in order to analyze the resource use between the IMs and the KPs, the “walk-in-the-wood” method and the participatory rural appraisal (PRA) were employed. This paper revealed that the local NTFP utilization gradually shifted from purely self-consumption to more income generation (p-value = 0.000 < 0.05). Besides, the IMs relied much upon the NTFPs, whereas the KPs were less dependent upon these resources. The IMs harvested these resources for more subsistence related to their traditional and basic needs than those KPs. Based on the local findings, the institutional management strategies in BGMNP should emphasize resource utilization patterns, human capital empowerment, and group-based arrangements. Likewise, group-based arrangements in BGMNP would play an important role in the local livelihood improvement and the sustainable park development.

Integrating Indigenous Knowledge into Sustainable Forest Management for Climate Change Adaptation and Mitigation Strategies

Mokhamad Asyief Khasan Budiman — 2025-01-24

Frequent natural disasters and extreme weather increase the vulnerability to climate change in rural communities living near forests. Climate change adaptation and mitigation strategies related to forest management should consider indigenous knowledge in accordance with local community conditions and needs. This study aimed to investigate the indigenous knowledge of forest management to cope with climate change challenges. The research was conducted in April - May 2024 in the southern slopes of Mount Slamet, Central Java (i.e., Gununglurah, Sokawera, and Sunyalangu Villages). The research approach uses Participatory Learning Action with descriptive-quantitative analysis based on interpretive and critical sociology. This study revealed that indigenous knowledge comprises three types of forest management. Firstly, the community categorized the forest into three types of space: sacred conservation forests (Tabet), protected forests in steep areas, and production forests using agroforestry. Secondly, the schedule of forest management activities was based on the traditional seasonal calendar (Pranatamangsa). Thirdly, plant types were selected based on their functions, i.e., productions, conservations, and spirituals.

Factors Affecting Bird Diversity in the Wetlands of Muara Gembong, Indonesia

Muhammad Hamas Fathani — 2025-01-24

Marshlands and backswamps are among the threatened habitats in Indonesia, along with mangroves, particularly in Java due to area development and land conversion. Muara Gembong is one of the remaining wetlands in Java and serves as one of the last refuges for the bird community in wetlands, particularly mangrove and marsh-associated birds. We observed bird communities and collected eleven habitat variables in three habitats, namely mangrove, marsh, and fishpond, to see which variable affects bird abundance and diversity most. We found out that the total number of plant species, along with the number of tree, understory, and shrub species, were the strongest factors affecting bird diversity in Muara Gembong. Separate analysis in each habitat, however, reveals that different abiotic factors also strongly correlate with bird diversity. Vegetation correlates strongly with bird diversity in mangroves and marshes, while pH and turbidity play a strong role in bird diversity in fishponds.

Big Data-Driven Risk Analysis of Environmental Grievances in the Palm Oil Industry for Sustainable Decision-Making

Muhammad Syahmi Idris — 2025-01-27

The expansion of the palm oil industry affects environmental sustainability. This study aims to assess palm oil's environmental grievances reported pre- and post-Covid-19. A hybrid of data-driven and multicriteria decision-making analyses was used to analyze unstructured data from nine companies' grievance logs. A total of 884 cases with the trend peaking in 2019. Predominantly deforestation, a total of 564 cases affecting ~66,716.23 ha in Indonesia, 312 cases affecting ~49,704.97 ha in Malaysia, 6 cases affecting ~43,500 ha in Papua New Guinea, and 2 cases in the Philippines. Network analysis reveals that the environmental grievances affected multiple companies, with WILMAR suppliers at the center. On average, companies take ~100 days to resolve. Clustering analysis shows Sime Darby Oil, WILMAR, KLK, and Mewah Group have influences on addressing grievances in high-risk provinces. Quantile-quadrant analysis reveals that provinces in Kalimantan, Pahang, and Sarawak are in the high-risk quadrant and therefore require immediate mitigation plans. This finding points toward the need for the formation of a private consortium among identified key players and local government in the high-risk region as a new strategy to improve management of environmental sustainability issues that predominantly involve deforestation.

Production Potentials of Quality Tree Seeds from Orchards and Plantations in Tanzania

Fortunate Stephen Senya — 2025-01-27

Availability of large quantities and high-quality planting materials is essential for sustainability of tree planting and quality forest products. However, there have been no sufficient information on production potential of quality and quantity of tree seeds. We assessed and compared seed production potential and germination capacity of four young (8 -14 years) and matured (15 -48 years) stands of plantations and seed orchards of Tectona grandis and Pinus patula located in different agro-climatic areas of Tanzania. In each seed source, 16 plots, measuring 100 x 100 m, were randomly selected. In each plot, seeds were collected from 30 trees bearing seeds and possessing good characters. Results showed that matured stands of T. grandis and P. patula produced significantly heavier seeds (51.4 kg ha^-1) (926.1kg ha^-1) than young stands (28.3kg ha^-1) (782.6kg ha^-1) respectively. The weight of seeds in orchards was significantly lighter (17.2kg/ha) than plantations (62.5kg/ ha) for P. patula whereas for T. grandis, the weight of seeds in orchards was heavier (911.8kg/ha.) than plantations (796.9kg/ha). Seeds from matured sources were significantly heavier than young seed sources (P<0.05). The weight of T. grandis and P. patula seeds were higher in seed orchards than plantations and plantation than seed orchards respectively.

Front-matter

Admin JMHT — 2025-01-27

https://doi.org/10.7226/jtfm.31.1.fm

Back-matter

Admin JMHT — 2025-01-27

https://doi.org/10.7226/jtfm.31.1.bm