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Land cover is crucial for island management, but the lack of accessible and high-resolution remote sensing data has reduced investigations on small islands, including land cover identification. Therefore, this study aimed to investigate land cover using Unmanned Aerial Vehicle (UAV) technology, providing very highresolution images. Classification and delineation were conducted using automatic segmentation followed by manual reinterpretation and visual verification. The results showed 14 cover classes, consisting of 8 vegetated and six non-vegetated categories. Forest cover on Mansinam island accounted for 75.5% or 302.4 ha, which was evenly distributed. Furthermore, primary forest covered 31.91% or 127.74 ha, and secondary covered 43.63% or 174.68 ha. The classification achieved an overall accuracy of 96% and a kappa coefficient of 0.94. Low-cost UAVs effectively produced high-resolution aerial images of small islands for land cover identification. Therefore, future studies were recommended to consider whether segmentation can reliably distinguish between primary and secondary forests, as well as assess the impact of flight altitude on segmentation accuracy using ground control points. The results were also expected to support spatial planning or sustainable forest and environment management on Mansinam Island. [ABSTRACT FROM AUTHOR]

Tropical forests play an important role in ecosystem services, yet anthropological activities have changed the ecological conditions. Thus, this research was designed to reveal the species richness and diversity in secondary forests, including the lifeform alteration. The 50 perpendicular plots were placed in both forests and distributed 25 for each. The study revealed that the secondary forest represents a stage of ecological succession in which species richness and diversity decreased. Additionally, the composition of life forms in the secondary forest changed, with dominant herbs indicating more dynamic vegetation due to shifting ecological conditions. Species classified as Threatened have disappeared due to human activities in the forest. However, the secondary forest has provided a habitat for certain species, including those with conservation status, such as Threatened or Extinct, to thrive and colonize, where approximately 15.7% of species exclusively thrive in secondary forests, including Antiaropsis uniflora C.C.Berg. Therefore, to promote sustainable forest management, this study suggests monitoring the species in secondary forests, particularly since the use of forests has traditionally been determined by local communities, including in restricted forest areas. Moreover, the local government could officially designate traditional forest use, thereby allowing restricted forests to be conserved as old-growth forests. [ABSTRACT FROM AUTHOR]

Healthy plants can be seen from good morphology and are not even attacked by pests. Local community knowledge of seeing symptoms and signs of plant stature will be very helpful, especially in dealing with problems related to plant growth. This study aims to determine the form of local wisdom in dealing with plant pests in residential areas around the Gunung Meja Nature Park. The method used is observation and interviews related to the identification of forms of attack, the level of pest attack on plants, and their handling by the community. The research object is focused on multipurpose tree species that produce wood and non-timber trees such as fruits that have high economic value. The results showed that the number of plant species in Anggori was 137 plants with a diversity index (H) of 2.956 which was included in the medium category. Plants in Anggori also suffered damage caused by pests with an attack frequency (FS) of 50% and attack intensity (IS) on plants of 21%. Pest control has been carried out by the community traditionally, such as 12% pruning, 8% logging, 20% fumigation, 8% stove ash and 16% soap to eradicate pest attacks. [ABSTRACT FROM AUTHOR]

Tree height is one of the important indicators in forest management, then to collect data in the field including the tree height is costly. We applied Unmanned Aerial Vehicle (UAV) to measure the tree height and then produced the proper equation. This study aims to test the ability of low-cost UAVs in estimating tree height and the distribution of tree height classes on Mansinam island. The canopy height model (CHM) approach through aerial photography using UAV can be used to quickly estimate the height of large-scale trees combined with field measurements. CHM analysis was carried out using spatial statistics to get tree height value based on the canopy. Photogrammetry results show that the obtained CHM has a resolution of 11,8 cm/pixel with the results of the evaluation of tree height accuracy having an RMSE of 2,4 m, MAE 2,0 m, SDE 3,8 m. The Statistical test shows that the tree height estimation accepts H0 and there is a strong relationship between the observed tree height and the estimation through linear regression with an R2 value of 0,67. The broad estimation of height shows that Mansinam island has a tree height in the range of 7 -- 66 m. This study shows that CHM obtained from aerial photography using low-cost UAVs is still able to estimate tree height well. Measuring tree height with a low-cost UAV can be another option for conducting a large-scale inventory. This research, tree height can be estimated quickly and can be carried out on a forest cover area. [ABSTRACT FROM AUTHOR]

Part of forests in Papua is still as logging concession. Pometia is one of target species, but there is still a lack of information regarding the ecological condition of this species. Thus, the objectives of this research were to describe what tree species (small and large individuals) associated with Pometia, how logging and soil properties influence the association and to analyze the structure of Pometia in term of diameter distribution. Canonical correspondence analysis (CCA) was applied to describe the association and its relationship with environmental factors (soil and litterfall). The results showed that association of small and large individuals of trees with both Pometia showed a different pattern in which the small individuals had a positive association and had certain tree species as a community. This association resulted from logging activity leading to the change in ecological conditions. Conversely, the association between large tree species with Pometia acuminata Radlk. and Pometia pinnata J. R. Forst. & G.Forst. showed negative pattern and tree species correlated with both Pometia were different. C content of litterfall had a positive correlation with large Pometia acuminata and its community . from environmental factors Furthermore, the small individuals of Pometia were dynamic as a response to logging in which a number of the small individuals of Pometia tended to increase after logging. [ABSTRACT FROM AUTHOR]

Some parts of forest in southern Papua Indonesia is used as production forest. Therefore, cutting is one of factors which has impact to population of trees. Research was done to see recuperation of non-commercial species (Actinodaphne nitida, Blumeodendron sp.) in logged area. Integral projection models (IPMs) were applied to analyze population dynamics of the 2 species. Mortality, growth, fecundity, autocorrelation of growth were included in IPMs. Data were collected from 3 permanent sample plots (3 ha) between 2005-2009 in PT. Tunas Sawaerma, Assiki, and Boven Digul. Data showed a significance in autocorrelation of growth. In this research, IPMs can be used to describe recuperation of the tree species. Population dynamics occur in which trees have the same survival probability among diameter size, while growth of trees and autocorrelations contribute to the change of population structure of trees. Elastisity test of growth autocorrelation pointed out that A. nitida and Blumeodendron sp remain to grow faster over time and have a larger contribution to population growth than other species. In addition, the more faster-growing individuals will have the more significant contributions for population growth rate of A. nitida and Blumeodendron sp. [ABSTRACT FROM AUTHOR]

Key message: Permanent sampling plots (PSPs) are a powerful and reliable methodology to help our understanding of the diversity and dynamics of tropical forests. Based on the current inventory of PSPs in Indonesia, there is high potential to establish a long-term collaborative forest monitoring network. Whilst there are challenges to initiating such a network, there are also innumerable benefits to help us understand and better conserve these exceptionally diverse ecosystems. [ABSTRACT FROM AUTHOR]