Population Structures of Four Tree Species in Logged-over Tropical Forest in South Papua, Indonesia: an Integral Projection Model Approach

Selective logging has been taking place in Papua for several decades. In contrast, very little is known about the stand structure in post-logged forest. Hence, this paper investigates stand structures in logged-over area of tropical forest in South Papua. Four species were selected in three one-hectare permanent sample plots (PSPs): Vatica rassak, Syzygium sp, Litsea timoriana and Canarium asperum. PSPs were located in the forest concession area of PT. Tunas Sawaerma in Assiki, Boven Digul, in South Papua. Data sets comprised measurements made in 2005 and 2012 consisting of species, diameter at breast height (DBH), mortality and number of tree of each species. Integral Projection Models (IPMs) were developed, taking into account mortality, growth, recruitment and fecundity. Results show the pattern of stand structures of the four species were more or less similar, i.e. more individual trees were present in the small diameter classes than in the larger diameter classes. The general pattern of the individual distribution of the four species is the typical reverse-J shape. Syzygium sp. has a greater number of individuals in the small diameter classes than the other three species. Population growth rates (λ) are above one, indicating that the stand structures of the population dynamics of the four species are recuperating. Conclusively, these results suggest that species composition and population structure in these logged-over forests are recovering increasingly

Persepsi Masyarakat Terhadap Pengelolaan Lingkungan Di Kelurahan Amban Kabupaten Manokwari

Pengelolaan lingkungan pada kelurahan Amban merupakan suatu hal yang menarik karena kawasan ini merupakan salah satu kawasan padat penduduk di Kabupaten Manokwari. Tujuan penelitian ini adalah untuk mengetahui bagaimana persepsi masyarakat terhadap pengelolan lingkungan pada kawasan ini. Metode yang digunakan dalam penelitian ini adalah metode survei dengan metode deskriptif dengan pembagian kasus atas enam kategori penilaian, dan didukung oleh data sekunder. Hasil penelitian menunjukkan bahwa sebagian besar masyarakat yang berada pada kelurahan Amban sangat setuju terhadap pola perencanaan pemanfaatan, pengendalian, pemeliharaan, pengawasan serta penegakan hukum yang dilakukan pada wilayah ini. Data ini diperoleh dari tiga wilayah yang tersebar pada wilayah Kelurahan Amban Manokwari.  

Secondary Succession after Slash-and-Burn Cultivation in Papuan Lowland Forest, Indonesia

Papuan forests have been subjected to shifting cultivation for centuries by indigenous people affecting the ecological processes therein; during secondary succession, fallow forests recover naturally. However, the information on ecological succession after swidden practices remains poorly understood in Papuan lowland forests. This study aimed to examine the plant species richness and density of different plant lifeforms in fallows of increasing time after slash-and-burn cultivation along with basic edaphic factors. We performed data collection in the northern part of the lowland evergreen tropical forest near Manokwari, West Papua, Indonesia. The sampling consisted of 26 plots distributed in the primary forest (n = 6) and in secondary/fallow forests 2-, 4-, 7-, and 9-years after cultivation (n = 5 for each age class). The plant community in primary forest clearly differed from the secondary forests. The plant species richness was about twice as high in primary compared to secondary forests. The density of trees and shrubs increased during succession whereas that of lianas declined. The soil fertility declined in secondary forests, although soil organic matter was greatest two years after swidden and then decreased gradually over time. This research underlined that indigenous swidden practices alter ecological conditions and that secondary forests will take a long time to fully recover to resemble primary forest. Hence, the monitoring of vegetation during the process is necessary to inform conservation programs

Co-limitation towards lower latitudes shapes global forest diversity gradients

The latitudinal diversity gradient (LDG) is one of the most recognized global patterns of species richness exhibited across a wide range of taxa. Numerous hypotheses have been proposed in the past two centuries to explain LDG, but rigorous tests of the drivers of LDGs have been limited by a lack of high-quality global species richness data. Here we produce a high-resolution (0.025° × 0.025°) map of local tree species richness using a global forest inventory database with individual tree information and local biophysical characteristics from ~1.3 million sample plots. We then quantify drivers of local tree species richness patterns across latitudes. Generally, annual mean temperature was a dominant predictor of tree species richness, which is most consistent with the metabolic theory of biodiversity (MTB). However, MTB underestimated LDG in the tropics, where high species richness was also moderated by topographic, soil and anthropogenic factors operating at local scales. Given that local landscape variables operate synergistically with bioclimatic factors in shaping the global LDG pattern, we suggest that MTB be extended to account for co-limitation by subordinate drivers

Opportunities and challenges for an Indonesian forest monitoring network

© 2019, INRA and Springer-Verlag France SAS, part of Springer Nature. 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

Co-limitation towards lower latitudes shapes global forest diversity gradients

The latitudinal diversity gradient (LDG) is one of the most recognized global patterns of species richness exhibited across a wide range of taxa. Numerous hypotheses have been proposed in the past two centuries to explain LDG, but rigorous tests of the drivers of LDGs have been limited by a lack of high-quality global species richness data. Here we produce a high-resolution (0.025° × 0.025°) map of local tree species richness using a global forest inventory database with individual tree information and local biophysical characteristics from ~1.3 million sample plots. We then quantify drivers of local tree species richness patterns across latitudes. Generally, annual mean temperature was a dominant predictor of tree species richness, which is most consistent with the metabolic theory of biodiversity (MTB). However, MTB underestimated LDG in the tropics, where high species richness was also moderated by topographic, soil and anthropogenic factors operating at local scales. Given that local landscape variables operate synergistically with bioclimatic factors in shaping the global LDG pattern, we suggest that MTB be extended to account for co-limitation by subordinate drivers

Co-limitation towards lower latitudes shapes global forest diversity gradients

The latitudinal diversity gradient (LDG) is one of the most recognized global patterns of species richness exhibited across a wide range of taxa. Numerous hypotheses have been proposed in the past two centuries to explain LDG, but rigorous tests of the drivers of LDGs have been limited by a lack of high-quality global species richness data. Here we produce a high-resolution (0.025° × 0.025°) map of local tree species richness using a global forest inventory database with individual tree information and local biophysical characteristics from ~1.3 million sample plots. We then quantify drivers of local tree species richness patterns across latitudes. Generally, annual mean temperature was a dominant predictor of tree species richness, which is most consistent with the metabolic theory of biodiversity (MTB). However, MTB underestimated LDG in the tropics, where high species richness was also moderated by topographic, soil and anthropogenic factors operating at local scales. Given that local landscape variables operate synergistically with bioclimatic factors in shaping the global LDG pattern, we suggest that MTB be extended to account for co-limitation by subordinate drivers

Model Pendugaan Diameter Pohon Berbasis Citra Unmanned Aerial Vehicle (Uav) Pada Hutan Hujan Tropis Papua: Studi Di Pulau Mansinam Papua Barat (Model of Tree Diameter Estimation Based on Unmanned Aerial Vehicle (Uav) Image in Papua Tropical Rain Forest: a Study in Mansinam Island Papua Barat)

Unmanned aerial vehicle (UAV) sudah sering digunakan untuk berbagai tujuan, bukan hanya untuk fotografi, namun telah dimanfaatkan untuk sains di berbagai bidang keilmuan, termasuk bidang kehutanan. UAV memiliki kemampuan bergerak dengan bebas di udara dan merekam objek di darat dengan resolusi spasial tinggi, dan cakupan areal yang luas. Penelitian ini bertujuan untuk melakukan pendugaan diameter setinggi dada (DBH) berdasarkan citra yang dihasilkan dari UAV. UAV digunakan untuk memperoleh foto udara yang diambil pada ketinggian 150 m di atas permukaan darat pada empat areal sampel seluas 27 ha di lokasi penelitian. Foto udara diproses dengan menggunakan perangkat lunak agisoft photoscan untuk menghasilkan Digital Elevation Model (DEM) dan ortofoto. Tajuk pohon dideliniasi dari ortofoto dan dianalisis untuk memperoleh luas dan diameter tajuk. Pengukuran DBH di lapangan dilakukan terhadap 206 pohon sampel yang selanjutnya digunakan untuk membangun model penduga DBH. Hasil uji korelasi menunjukkan bahwa diameter tajuk mempunyai korelasi yang tinggi dengan DBH sehingga variable ini digunakan sebagai variable bebas. Model terbaik penduga DBH adalah model polinomial dengan persamaan y = 0,0118744 x² + 1,08835 x + 22,8125, dengan y adalah DBH dan x adalah diameter tajuk hasil interpretasi foto udara. Pendugaan DBH menggunakan UAV memiliki beberapa manfaat seperti mampu mengurangi waktu, biaya dan tenaga kerja

Status Kawasan Hutan dan Potensi Ekowisata Pantai Syari di Kabupaten Manokwari Selatan

Pantai syari merupakan salah satu objek wisata di Kabupaten Manokwari Selatan berada di poros Jalan Trans Papua Barat yang menghubungakan antara Kabupaten Manokwari, Kabupaten Manokwari Selatan dan Kabupaten Teluk Bintuni. Ekowisata Pantai Syari merupakan jasa lingkungan yang unik, dimana dalam hutan dataran rendah terdapat tiga tipe hutan dalam suatu kawasa hutan yaitu, hutan rawa, hutan mangrove dan hutan pantai. Tidak hanya hutan dataran rendah saja yang dimiliki ekowisata Pantai Syari namun ada destinasi wisata lain yaitu destinasi wisata religi yang berada di pantai ini. Kawasn hutan Pantai Syari menurut SK 783/Menhut-II/2014 terdiri dari Kawasan Hutan Areal Penggunaan Lain  dan Hutan Produksi yang dapat dikonvesi, sehingga ada beberapa mekanisme yang perlu dilakukan untuk mengelola ekowisata Pantai Syari secara optimal