Indonesia has 14 million ha of degraded and marginal land, which provides very few benefits for human wellbeing or biodiversity. This degraded land may require restoration. The leguminous tree Pongamia pinnata syn. Milettia pinnata (pongamia) has potential for producing biofuel while simultaneously restoring degraded land. However, there is limited information on this potential for consideration. This paper aims to address the scientific knowledge gap on pongamia by exploring its potential as a biofuel and for restoring degraded land in Indonesia. We applied a literature review to collect relevant information of pongamia, which we analyzed through narrative qualitative and narrative comparative methods with careful compilation and scientific interpretation of retrieved information. The review revealed that pongamia occurs naturally across Indonesia, in Sumatra, Java, Bali, Nusa Tenggara and Maluku. It can grow to a height of 15–20 m and thrive in a range of harsh environmental conditions. Its seeds can generate up to 40% crude pongamia oil by weight. It is a nitrogen-fixing tree that can help restore degraded land and improve soil properties. Pongamia also provides wood, fodder, medicine, fertilizer and biogas. As a multipurpose species, pongamia holds great potential for combating Indonesia’s energy demand and restoring much of the degraded land. However, the potential competition for land and for raw material with other biomass uses must be carefully managed.

Globally, planted forests are increasing, providing increased resources to forest industries and ecosystem services (ES) to local and wider communities. However, assessment of the impacts of plantations on ES has been limited. Planted forests have expanded rapidly in Vietnam over the last 20 years, with much of the planting undertaken by smallholder growers using exotic Acacia and Eucalyptus species. This study aimed to test a framework to assess changes in four ES due to an increase in Acacia plantations from 2005–2015 in central Vietnam: carbon sequestration, sediment retention, water yield and habitat. Quantitative and qualitative indicators for each service were derived from the literature. Results showed that the area of planted forests in Quảng Trị and Thừa Thiên-Huế Provinces increased from 130,930 hectares (ha) to 182,508 ha, mostly replacing non-forest areas (degraded lands, grasslands and agricultural lands) and poor forests. The framework demonstrated capacity to assess the effect of planted forests on wood flow, carbon stocks, sediment retention, streamflow and the extent of wildlife habitat. Apart from the wood supply and carbon sequestration, more research is required to translate biophysical indicators to benefit relevant indicators related to human welfare. The study also revealed that the area of rich forests decreased by 20% over the ten years, mostly through degradation to poorer quality natural forests. Therefore, at the landscape scale, improvement in ES due to conversion of non-forests to planted forests was offset by a reduction in some services as a result of degradation of native forest from rich to poorer condition. Assessment of changes in ES due to planted forests also needs to consider other landscape changes. These analyses can inform policymakers, forest owners and managers, environmental organizations and local communities of the benefits and impacts of planted forests and provide an improved basis for payments for ES and potential additional income for smallholder tree growers.

Large areas of deforested and degraded land, particularly degraded peatlands, need a viable long-term solution for restoration, ideally one that ensures energy security without compromising food security or biodiversity conversation. To address a knowledge gap on the most adaptive bioenergy crop(s) for degraded lands, this research project assessed the survival and growth performance of potential bioenergy crops to restore burned and degraded peatlands. Our methodology compared the bioenergy species with the potential to survive in extreme environments, i.e., gamal [Gliricidia sepium (Jacq.) Walp.], kaliandra (Calliandra calothyrsus Meissner), kemiri sunan [Reutealis trisperma (Blanco) Airy Shaw], and nyamplung (Calophyllum inophyllum L.). Observed parameters are plant survival rates, tree height, and circular stem growth. The experiment was conducted between March 2016 to February 2017 in a two-hectare demonstration plot on burned and degraded peatland in Buntoi village, Pulang Pisau, Central Kalimantan province. Using a split plot design, two treatments were given to each species, i.e., monoculture plantation and agroforestry (intercropped with Ananas comosus (L.) Merr.); with each treatment, the species were replicated on two separate plots. Results indicate that nyamplung is the most adoptable species followed by kemiri sunan, however both species performed very well under agroforestry treatment when compared with monoculture. Further study is needed to assess the productivity and associate biofuel yield.