T hrough the Bonn Challenge (www.bonnc halle nge.org) and the multinational New York Declaration on Forests agreement, participating nations have made an unprecedented commitment to restore 350 million ha of degraded land by 2030. However, there remains a huge gap between political rhetoric and the reality of implementing restoration at this scale (Fagan et al. 2020). In bridging this gap, a key role exists for novel policy instruments that encourage private investment in restoration (Brancalion et al. 2017). Unsustainable logging has led to the depletion of timber resources across vast swaths of tropical forests (Cerullo and Edwards 2019). For example, in Indonesia in 2018, of the 56.5 million ha of natural forests officially under production forest licenses, 38.2 million ha were abandoned by the license holder (MOEF 2018). These forests are vulnerable to encroachment (Burivalova et al. 2020) and, because they do not earn government revenue, are often converted to plantations and are specifically excluded from Indonesia's moratorium on deforestation (Sloan et al. 2012). However, selectively logged tropical forests (see nutshell for definition) retain large amounts of carbon (C), support high levels of biodiversity, and provide many other ecosystem services (Berry et al. 2010; Fisher et al. 2011b; Chazdon 2014). Restoring selectively logged tropical forests will therefore be critical if ambitious global restoration and conservation targets are to be achieved (Cerullo and Edwards 2019). Can restoration of selectively logged forests be economically viable? To address this question, we reviewed over a decade's worth of evidence regarding restoration concessions in Indonesia, based on experience among the authors (RDH, TS, AA, and MS) of managing a 98,000 ha restoration concession in Sumatra since 2007, the responses of license holders to a short survey conducted in November 2016, and participation

Problem statement: There was no information about the relationship between growth parameters, such as diameter and height and tree component biomass of Khaya ivorensis plantations with different soil types. The objectives of this study were, first, to determine and compare the growth of K. ivorensis in three different (Padang Besar, Durian and Rengam) soil series of Ultisols and, second, to develop an allometric equation that estimates the biomass accumulation of the K. ivorensis plantation in three different soil series five years after planting. Approach: This study was conducted at a K. ivorensis plantation in the Forest Research Institute Malaysia (FRIM) Research Station in Segamat, Johor, Malaysia. The tree height (H) and Diameter at Breast Height (DBH) were measured to evaluate the growth performance of the K. ivorensis plantation. Five sampled or trees stand of K. ivorensis in each soil series were destructively analyzed. Results: The highest growth rates in terms of MAI diameter and height, and basal area were found for the Padang Besar soil series, which was followed by the Durian and Rengam soil series. The best fit regression of site-specific equations developed from the independent variable D are recommended for estimating tree component biomass and stem volume in each site. A single allometric equation using D was applicable for the estimation of biomass and stem volume however, in Padang Besar, stem biomass and stem volume were estimated with an equation using D 2 H. The highest stem volume and biomass accumulation value were recorded at Padang Besar (77.99 m 3 h −1 and 63.16 t ha −1 , respectively), which was followed by the Durian (53.10 m 3 h −1 and 46.33t ha −1 , respectively) and Rengam soil series (43.13 m 3 h −1 and 40.96 t ha −1 , respectively). Conclusion: Differences in the growth and biomass accumulation data indicate that forest productivity of K. ivorensis was affected by different site conditions. The higher growth performance and productivity of K. ivorensis in terms of the stem volume and biomass accumulation in Padang Besar compared those in the Durian and Rengam soil series shows that the species was able to adapt to the soil characteristics of the Padang Besar soil series.

Problem statement: It is widely accepted that conversion of natural forest to other land use types leads to deterioration of soil fertility and increased soil compaction which consequently become degraded secondary forests. Degraded secondary forest is indicated by low soil fertility and organic matter due to imbalance input and output from original vegetation. Forest plantation through planting fast growing exotic species is usually implemented to curtail degradation of secondary forest or forestland and to improve the soil fertility through organic matter accumulation. However, fundamental information on degraded forestland being converted to forest plantation using exotic species such as Khaya ivorensis is not available. The objectives of this study were: (1) to characterize the properties of three degraded soils under rehabilitation using K. ivorensis; and (2) to evaluate their fertility status by Soil Fertility Index (SFI) and Soil Evaluation Factor (SEF). Approach: This study was concentrated on three soil series (Rengam, Durian and Padang Besar) found under K. ivorensis plantation and at the adjacent secondary forest in Segamat, Johor, Malaysia. To characterize and evaluate the soil fertility status for each soil series, three plots (30 x 40 m) were randomly established on each soil series. Soils for each series were sampled at the depth of 0-10 cm (surface soil) and 20-30 cm (subsurface soil). They were randomly collected at six different points for each replicate. Soil analyses were carried out physical and chemical properties. Results: The soils both in planted and secondary forests were moderately acidic to slightly acidic with low content of exchangeable bases and available P but high in Al saturation. The Rengam series under K. ivorensis plantation contained higher total carbon and clay compared with those of Padang Besar and Durian series. Clay and total carbon contents were highly correlated with the Cation Exchange Capacity (CEC), indicating the potential of negative charge produced by the clay and organic playing an important role in supplying and holding plant nutrients. The SFI result revealed that soil fertility status of Rengam soil was significantly higher than the other two soil series. There was no significant difference observed for SEF. Based on SFI and SEF values, there were no significant differences of fertility status between the planted and secondary forests for both soil depths. Conclusion: This study revealed that Rengam soil is more fertile than the other two soils. Based on the using SFI and SEF it can be concluded that fast growing exotic species of K. ivorensis has the potential to improve site productivity and soil fertility

Problem statement:There is general agreement that human activities such as deforestation and land use change to other land use types have contributed to degraded secondary forests or forestland and increases the emission of greenhouse gases which ultimately led to global climate change. An establishment of forest plantation in particular is regarded as an important approach for sequestering carbon. However, limited information exists on productivity and potential of fast growth exotic and indigenous tree plantations for sequestering CO 2 from the atmosphere through photosynthesis. This study aimed at assessing the productivity and biomass accumulation along with the potential for sequestering CO 2 of planted exotic and indigenous species on degraded forestland. Approach: This study was conducted at Khaya ivorensis and Hopea odorata plantations, which was planted at the Forest Research Institute Malaysia (FRIM) Research Station in Sega mat Johor, Malaysia five years ago. In order, to evaluate the forest productivity and biomass accumulation of both species, we established plots with a size of 40x30 m in three replications in each stand, followed by measuring all trees in the plots in terms of height and Diameter at Breast Height (DBH). To develop allometric equation, five representative trees at each stand were chosen for destructive sampling. Results: The growth performance in terms of mean height, DBH, annual increment of height and diameter and basal area of exotic species (K. ivorensis) was significantly higher than that of the indigenous species (H. odorata). We used the diameter alone as independent variable to estimate stem volume and biomass production of both species. The stem volume of K. ivorensis stand was 43.13 m 3 ha −1 and was significantly higher than H. odorata stands (33.66 m 3 ha −1 ).The results also showed that the K. ivorensis and H. odorata stands have the potential to absorb CO 2 from the atmosphere which was stored in aboveground biomass with value 15.90 Mg C ha −1 and 13.62 Mg C ha -1 , respectively. In addition, the carbon content in root biomass of H. odorata stand was higher than that in K. ivorensis stand with value 7.67 Mg C haand 4.58 Mg C ha −1 , respectively. Conclusion/Recommendation:The exotic (K. ivorensis) and indigenous (H. odorata) species which was planted on degraded forestland exhibited different growth rate, biomass production and ability to absorb CO 2 from the atmosphere in each part of the tree. In general, forest productivity and ability to absorb CO 2 from the atmosphere of exotics species (K. ivorensis) was higher than that indigenous species (H. odorata). These findings suggest that forest plantation productivity has been affected by species characteristics and suitability of species to site condition. Thus, to sustain high productivity with suitable species selection for carbon sequestration, these factors should be considered for future forest establishment.

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.

Harapan rainforest situated in South Sumatera is a restoration area of PT REKI company that highly susceptible to land conversion. The problem faced in the effort of restoration is the restorated area that is too large and has not been tested any silvicultural techniques. The condition of land cover is the basic information that could be used as a reference in the preparation of restoration strategy. The study aimed to determine the level of damage, the condition of the ecosystem, appropriate silvicultural techniques, and plant species restoration priorities. The used methods were analysis of vegetation in 4 typologies (secondary forest, old shrub, young shurb, former akasia plantations). The order of area with the level of damage from the lowest to the highest were: the typology of secondary forest, old shurb, young shrub, and former akasia plantation, respectively. The typology of secondary forests had the highest value of diversity, richness, and evenness (H'>3, Dmg>5, and E>0.6). Relationship between former akasia plantations typology and another tipologies was not germane (euclidean distance> 3.31), and the relationship between seedling and trees in all typologies (with the exception of former akasia plantations) was very high (r> 0.9). Silvicultural techniques that could be done include eradicating A. mangium in the former akasia plantation and planting in the all typologies with the exception of secondary forest. The plants that could be used for restoration are Macaranga sp.

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planting density and the practice of thinning. Density effects on stand growth and Pinus merkusii Jungh. et D HtMortality and D growth were positively density related, but H growth was not affected by density. During the measurement period, tree density decreased from 7779 to 679Results suggested that optimal harvesting was at about 30 years of age if no thinning occurs. The SDMD was established to predict the course of stand development in merkus pine. The simulation of stand growth under 2m x 3 m spacing and thinning