Based on habitat preferences, in this study, we investigated the spatial distribution of the Magnolia genus in the northern part of Sulawesi. Habitat characteristics, especially temperature, precipitation, and topography, were determined using spatial analysis. The temperature and precipitation datasets were obtained from WorldClim BIO Variables V1, and topographical data were obtained from the Google Earth Engine. Data collection began in 2008–2009 and was completed in 2019–2020. In total, we analyzed 786 waypoints. The genus distribution was then predicted based on the most suitable habitat characteristics and mapped spatially. This study confirmed that Magnolia spp. distribution is affected by the annual temperature range, precipitation seasonality, and elevation. We discovered endemic and endangered species, Magnolia sulawesiana Brambach, Noot., and Culmsee, that were previously distributed exclusively in the central part of Sulawesi. Five waypoints of the endemic species were found in the conservation area of the Gunung Ambang Nature Reserve and on the border of Bogani Nani Wartabone Nation Park. In general, M. sulawesiana is distributed at higher elevations than other Magnolia species. This study provides a scientific basis for forest officers to develop in-situ and ex-situ conservation strategies and landscape protection measures to maintain the sustainable use of the genus, especially the sustainability of endemic species.

Most of the Indonesian agarwood in the international market is harvested from the wild, which raises concerns regarding its sustainability. The Government of Indonesia encourages agarwood cultivation produced from the cultivated Agarwood-Producing Tree (APT) to overcome this concern and replace natural agarwood. APT cultivation in Indonesia is not a new development, but it has faced various obstacles, ranging from production quantity and quality to funding and marketing. Therefore, an appropriate policy is needed to support the success of APT cultivation. This study aims to develop a dynamic system model in order to identify the gaps and determine appropriate policy strategies to improve APT cultivation in Indonesia. The model was established by compiling three conceptual stages: planting to harvest, cost–benefit analysis, and feasibility analysis. Agarwood from Aquilaria malaccensis Lam. cultivated by the community and private sector, which produces kemedangan (an agarwood grade in the Indonesian market) and oil, was chosen for the model. The model developed shows that APT cultivation development in the private sector and the community is unfeasible with the business as usual. There are three options to simulate the feasibility of agarwood produces from APT cultivation. The best scenarios are chosen based on the feasibility indicator, when benefit is higher than cost. The development of APT by the private sector that produces kemedangan and oil products is feasible, with the invention of more effective inoculant and processing technology (scenario 1), as well as applying high thinning, which can increase the yield. Oil production requires more investment, so the revenue obtained is lower than the production cost, resulting in the unfeasibility of the production. The development of APT by the community will be feasible with scenario 2, if there is government funding for the establishment of APT cultivation, inoculants application, and harvesting. Based on the model scenario, APT cultivation will be ecologically sustainable, economically feasible, and socially acceptable if carried out by the private sector or the community by applying inoculation techniques and selecting inoculants to increase production effectiveness, and will be supported by lower production costs and market stability. The Indonesian government needs to take several policies to encourage APT development, including financial assistance for APT development, setting inoculant standards at affordable prices, simplifying trade administration, stabilizing agarwood product prices at the local level, and law enforcement.

Indonesia has around 4000 wood species, and 10% (400) of species are categorized as commercial wood. One species is kayu kuku (Pericopsis mooniana Thwaites), native to Southeast Sulawesi. This species is considered a fancy wood used for sawn timber, veneer, plywood, carving, and furniture. The high demand for wood caused excessive logging and threatened its sustainability. In addition, planting P. mooniana has presented several challenges, including seedling production, viability and germination rate, nursery technology, and silviculture techniques. As a result, the genera of Pericopsis, including P. elata (Europe), P. mooniana (Sri Lanka), and P. angolenses (Africa), have been listed in the Convention on International Trade in Endangered Species (CITES) Appendix. Based on The International Union for Conservation of Nature (IUCN) Red List of Threatened Species, P. mooniana is categorized as Vulnerable (A1cd). This conservation status has raised issues regarding its biodiversity, conservation, and sustainability in the near future. This paper aims to review the conservation of potential and endangered species of P. mooniana and highlight some efforts for its species conservation and sustainable use in Indonesia. The method used is a systematic literature review based on P. mooniana’s publication derived from various reputable journal sources and additional literature sources. The results revealed that the future demand for P. mooniana still increases significantly due to its excellent wood characteristics. This high demand should be balanced with both silviculture techniques and conservation efforts. The silviculture of P. mooniana has been improved through seed storage technology, improved viability and germination rates, proper micro and macro propagation, applying hormones, in vitro seed storage, improved nursery technology, and harvesting techniques. P. mooniana conservation can be conducted with both in situ and ex situ conservation efforts. In situ conservation is carried out by protecting its mother trees in natural conditions (i.e., Lamedae Nature Reserve) for producing good quality seeds and seedlings. Ex situ conservation is realized by planting seeds and seedlings to produce more wood through rehabilitating and restoring critical forests and lands due to its ability to adapt to marginal land and mitigate climate change. Other actions required for supporting ex situ conservation are preventing illegal logging, regeneration, conservation education, reforestation, agroforestry system applied in private and community lands, and industrial forest plantations.

Vegetation dynamics in dipterocarp forest permanent plots after fire (1997-1998) is important to monitor due to the successional process. Monitoring was conducted from 2001 to 2013 to record tree individuals with a more than 4.8 cm diameter. The highest species diversity was found in 2013 (249 species), then decreased in 2022 (237 species). Dominant species during monitoring change from Macaranga gigantea (Euphorbiaceae) and Madhuca kingiana (Sapotaceae) (2001-2002) to M. gigantea (Euphorbiaceae) and Vernonia arborea (2005-2013) and then M. gigantea (Euphorbiaceae) and M. kingiana (Sapotaceae) (2022). Shannon-Wiener diversity index (H’) in 2022 indicates that species diversity in this permanent plot is high (4.85). The class diameter of trees in the permanent plot is dominated by small individuals (DBH <10 cm). The highest diameter increments are M. gigantea (0.42 cm year^-1) and V. arborea (0.41 cm year^-1) in the 5-10 cm diameter class. The highest tree recruitment found in 2005 (41.62%). Mortality rate from 2013-2022 was 3.16%, with high contribution from M. gigantea (141 individuals). Carbon storage value from 2001 to 2022 increased from 38.91 tons ha^-1 (2001) to 114.29 tons ha^-1 (2022). Successional process in this permanent plot needs to be monitored to assess forest health.