Penelitian ini bertujuan untuk menentukan model perkembangan lebar tajuk pohon dominan jati asal Kebun Benih Klon pada tegakan berkualitas baik.Penelitian dilakukan di Kesatuan Pemangkuan Hutan Ngawi pada petak tanaman jati asal Kebun Benih Klon bertumbuhan baik pada umur 615 tahun. Petak tanaman bertumbuhan baik ditentukan berdasarkan kriteria persentase keberhasilan tanaman, rata-rata tinggi pohon dan rata-rata diameter batang serta aksesibilitasnya. Pada petak yang memenuhi syarat bertumbuhan baik dipilih sebanyak 30 sampel pohon dominan dan tiap sampel diukur radius tajuk pada empat arah mata angin. Hasil pengukuran radius tajuk digunakan untuk menghitung rata-rata radius tajuk sebagai rata-rata kuadratik 4 arah pengukuran radius tajuk dan lebar tajuk sebagai dua kali rata-rata radius tajuk. Rata-rata aritmatik dari lebar tajuk 30 pohon dominan tiap petak pengukuran digunakan sebagai variabel respons dan umur tegakan sebagai variabel prediktor. Data pengukuran selanjutnya dipilah menjadi dua bagian, yaitu sebagian besar untuk pengembangan model dan satu bagian lagi untuk validasi model. Analisis regresi non linear dengan metode kuadrat terkecil digunakan untuk memilih 4 kandidat model penduga rata-rata lebar tajuk, yaitu model Sigmoid, Power, Schumacher dan Gompertz. Pemilihan model didasarkan atas nilai koefisien determinasi tertinggi dan standard error of the estimate terkecil serta signifikansi uji F dan uji T. Akhirnya, model terbaik diuji kelayakannya dengan kriteria root mean squared error, simpangan agregatif dan simpangan relatif. Model Gompertz adalah model terbaik untuk memprediksi perkembangan rata-rata lebar tajuk pohon dominan, yang dapat dituliskan dengan persamaan: CW = 6,585 Xe-0,705xe-0,091sage dan dapat menjelaskan 79% variasi data. Model tersebut lolos validasi dan layak digunakan untuk memprediksi rata-rata lebar tajuk pohon dominan jati asal Kebun Benih Klon pada tegakan berkualitas baik umur 6 tahun sampai dengan umur 15 tahun di Kesatuan Pemangkuan Hutan Ngawi.
Predicting Crown-width of Dominant Trees on Teak Plantation from Clonal Seed Orchards in Ngawi Forest Management Unit, East JavaAbstractThis study aims to determine the model of crown width development of the dominant teak tree planted using seeds from clonal seed orchards. The research was carried out in Ngawi Forest Management Unit on the good quality teak compartment having stands age from 6 to 15 years old. The good quality compartments were determined based on higher stand density, taller average tree height, larger average stem diameter, and good accessibility. In a well-qualified compartment, 30 samples of the dominant tree were selected and each sample was measured for the crown radius in the four radii. The measured crown radius was used to calculate average crown radius as a quadratic mean of 4-crown radii and crown width as double of average crown radius. The arithmetic mean of the crown width of the 30 dominant trees in each measured compartment was used as the response variable and stand age as the predictor variable. The measurement data were then sorted into two parts, namely: mostly for model fitting and the remaining for model validation. Non-linear regression analysis with the least squares method was used to evaluate 4 candidate models of average crown width, namely: Sigmoid, Power, Schumacher, and Gompertz models. The model selection was based on the highest coefficient of determination and the smallest standard error of the estimate and the significance of F test and T test. The best model was eventually validated using the following criteria : root mean squared error, aggregate deviation, and relative deviation. Gompertz model was the best model to predict the average crown width development of dominant teak tree and expressed as: CW = 6.585 Xe-0.705xe-0.091xage and able to explain 79% variation of data. The model was passed based on statistical validation and it was feasible for predicting the average of crown width of dominant teak tree from clonal seed orchards on good quality stand aged 6 to 15 years in Ngawi Forest Management Unit.

This study investigated the land cover changes, carbon storage dynamics and their underlying socio-economic processes before and after a community forest permit in Bleberan village, Gunungkidul, Indonesia, during 1999-2018. We used a combination of the forest canopy density model, carbon conversion and socio-economic related data to analyze land cover classes in the periods of 1999-2003, 2003-2009, and 2009-2018, representing the phases of several years before community forestry permit, initial phase of community forestry establishment and several years after community forestry permit, respectively. Results showed that at baseline (1999), where illegal logging was started on the ground, the condition of the 40 ha investigated area was dominated by non-forest in the form of open land by 54% with an amounted carbon storage of 1352.62 ton. In the phase of before community forestry permit (1999-2003), when there was continuous illegal logging, the open land rise quickly achieved to 83%, with only 312.09 ton of carbon storage remaining. In the initial phase of community forestry establishment (2003-2009), when the government issued a legalization of community forest, the mixed dryland agriculture shifted to dominate the area by 55%, with the carbon storage being increased to 1840.94 ton. The last phase, several years after community forestry permit (2009-2018), which characterized by active engagement of the community in forest rehabilitation, the area was altered to fully stocked teak plantation forest by 82%, with a carbon storage enhancement of 3379.16 ton or two times higher than that at baseline. Such results are important for the forest community authority and related stakeholder for designing appropriate forest-related policies and supporting REDD + implementation.

Background: Wood biomass from forests is a renewable energy source that has the potential to support global green development. However, the process of traditional firewood extraction and its contribution to the energy supply varies and is usually underrecognized, especially in the local context. Therefore, this study aimed to describe the traditional use and estimate the supply and demand for wood bioenergy from small-scale privately owned forests (SSPF) in Ciamis Regency, West Java Province, Indonesia. Methods: The sample location was determined in 3 subdistricts, namely, Sukamantri, Ciamis, and Banjaranyar, which represent the northern, central, and southern regions, respectively. The data were collected through observations on stands, interviews with respondents, key informants from users and business actors of wood in the SSPF, and observations on the processes taking place in the flow and use of biomaterials and firewoods. Results and conclusion: Firewood is a secondary product that cannot be separated from the main products along SSPF’s chain of production based on the integration of raw material sources, linkages between actors, and volume sharing. The local knowledge and wisdom entanglements included the identification of the type and quality of firewood, distribution of resource allocation for household and industrial needs, and sharing of firewood for household needs. Although wood biomass contributes to the fulfillment of households and industrial needs of 8.51 million m³, there are indications of an imbalance between the potential supply and the demand for firewood due to its high intensity of use in industries. Therefore, multistakeholder and cross-regional support are needed to achieve sustainable SSPF management and fulfill the self-sufficiency of wood energy.

Sadono R, Soeprijadi D, Susanti A, Matatula J, Pujiono E, Idris F, Wirabuana PYAP. 2020. Local indigenous strategy to rehabilitate and conserve mangrove ecosystem in the southeastern Gulf of Kupang, East Nusa Tenggara, Indonesia. Biodiversitas 21: 1250-1257. The existence of local communities around mangrove ecosystems plays essential role to support the effort of conservation programs in this area. This study is aimed to investigate a set of situation faced by local communities in the southeastern Gulf of Kupang (SGK), East Nusa Tenggara Province which led to the rehabilitation of once degraded mangrove forests in SGK and the strategies to conserve the recovered mangrove forests. A case study approach was developed using purposive sampling to collect information regarding the historical situation of mangrove forests in SGK. Further, remote sensing method using multi-temporal observation data was used to investigate the changes in mangrove cover from 1994 to 2019. This study revealed that a series of situations became the fundamental of the success in retaining the existence of mangrove ecosystems in SGK. First, the negative impacts of mangrove degradation affected the communities badly in relation to their livelihoods in fisheries and marine sector as well as other environmental services. Then, this situation led to the emergent of a local champion to initiate mangrove rehabilitation efforts which firstly did not get attention from most of the communities. After some initial successes, the efforts of the local champion was then followed by other members of communities, triggering a bigger scale of mangrove rehabilitation. Having the mangrove recovered, the communities set of highly strict local indigenous rules in which every indigenous people who conducting illegal logging in the mangroves would be expelled from the village, while a large fine was given for outside people who did the similar action. Currently, more than 90% of respondents have understood the benefits of mangroves and derived advantages from it, particularly in improving their prosperity and security. The results of the success of mangrove rehabilitation and conservation in SGK was confirmed by the increasing extent of mangrove vegetation using remote sensing data. The case study of rehabilitation and conservation in SGK provided valuable learning for communities in other areas.