Vietnam’s forests have experienced a notable transformation over the past 20 years from net deforestation to reforestation and expanding forests. Continued reforestation that aims to achieve further economic and environmental benefits remains a national priority and strategy. We explore the current status of plantation forests and highlight possible means to facilitate their expansion in the uplands of Vietnam. We employ mixed method triangulation to empirically explore plantation forests and their economic role in household livelihood, to quantify trade-offs between plantation forests and shifting cultivation, and to assess the constraints on plantation forest expansion in Nghe An province, north-central Vietnam. Results show that forest in the study area expanded by 406,000 ha (71.1%) between 1990 and 2016. Plantation forests increased by nearly 500% (from 32,000 ha to 190,000 ha), while natural forests expanded by 48.1% (from 538,000 ha to 797,000 ha). Plantation forests contributed an average of 35.1 percent of total household income in wealthier households and 27.9 percent of income in poor households. Switching from shifting cultivation to plantation forests would increase total household income and average carbon stock but decrease food provision. Total Economic Value would be higher for plantation forest scenarios if increased carbon stocks in plantations can be monetized. This carbon income might drive conversion of shifting cultivation to plantation forests. Constraints on further expansion of plantation forest are low external cooperation, education, market stability, and agroforestry extension services. Our empirical results inform national plantation forest development, sustainable upland livelihood development, and climate change mitigation programs to ultimately facilitate forest transition and improve the resilience and sustainability of socio-ecological systems.

Mangroves are recognized as a highly valuable resource due to their provision of multiple ecosystem services. Therefore, mangrove ecosystems mapping and monitoring is a crucial objective, especially for tropical regions. Thai Binh province is one of the most important mangrove ecosystems in Vietnam. The mangrove ecosystem in this province has faced threats of deforestation from urban development, land reclamation, tourism activities, and natural disasters. Recently, to maintain the fundamental functions of the ecosystems, a large mangrove area was planted in Thai Binh. The aim of this research is to detect the change in the mangrove areas and to create an aboveground biomass map for mangrove forests in Thai Binh province. Landsat and Sentinel-2 satellite images from 1998 to 2018 were analysed using the supervised classification method to detect mangrove area change. Mangrove Above-ground Biomass (AGB) was estimated using linear regression between vegetation indices and field AGB survey. The accuracy assessment for the classified images of 1998, 2003 and 2007, 2013 and 2018 are 93%, 86%, 96%, 94% and 91% respectively with kappa of 0.8881, 0.7953, 0.9357, 0.9114 and 0.8761. The mangrove cover in the study area was estimated at 5874.93 ha in 1998. This figure decreased significantly to 4433.85 ha in 2007, before recovery began to take place in the study area, which was estimated at 6587.88 ha in 2018. In 1998, the average AGB in this study area was 22.57 ton/ha, and in 2018 it was 37.74 ton/ha with a standard error of 12.41 ton/ha and the root mean square error (RMSE) was ±12.08 ton/ha.

Climate change continues to pose a constant threat to nature and human beings, and thus demands adaptability and flexibility in forestry and domestic land use management. In this context, the Reducing Emission from Deforestation and Forest Degradation (REDD+) project was introduced to harness forests to curb greenhouse gas emissions in an effort to combat climate change. As of 2020, REDD+ was implemented in 65 countries across the world, including Vietnam. While the missions of afforestation and forest protection cannot be accomplished without the aid of local residents, low participation from stakeholders, particularly poor farmers, is an obstacle in climate mitigation projects. To contribute to improving REDD+ with a useful Vietnam reference, this study uses a random sample approach coupled with a face-to-face interview method to survey 215 households in Chau Thai, one of 206 poor communes in Nghe An province, to learn about (1) residents’ perception towards the importance of forests, (2) how forests contribute as a source of livelihood, (3) potential for household engagement in REDD+. The research findings show that the important role of forests is well acknowledged, the majority of forestland was allocated to plantation forests, and the seeds are carefully selected to satisfy market demand. In addition, forests are recorded to make major contributions to residents’ income and roughly four-fifths of households revealed their willingness to get involved in the REDD+ project with a monthly subsidy of 500–2000 kVND (22.3–89.2 USD). The study provides valuable information about forest-based rural livelihood and policy options to facilitate REDD+ participation among farmers. This, in turn, helps devise more appropriate policies for climate change mitigation and sustainable rural mountainous development nationwide and beyond.

Most of the extraordinary biodiversity richness of South-East Asian countries is concentrated in the national parks and other Protected Areas, with species-rich turtle communities surviving mostly in these reserves where their natural habitats are better preserved. However, very few studies have documented the turtle species richness of the various Protected Areas in Vietnam, which is not only one of the hotspots of chelonian diversity in the world but also one of the countries where their exploitation is the highest. Here, the diversity of turtles is studied in the Bach Ma National Park in central Vietnam, mainly characterised by forested hills and mountains, with ponds and streams of various shapes and structures. The study was carried out by conducting (i) semi-structured interviews of hunters recruited through a snow-ball procedure in local villages, (ii) inspection of turtle individuals in their hands, (iii) field surveys along random transects inspecting the various microhabitats used by these reptiles. We observed a total of 15 species, out of which 14 (93.3%) are threatened, based on IUCN Red List. A natural hybrid of Cuora bourreti × C. mouhotii obsti (Cuora «serrata») was observed. Three species (Cuora bourreti, Manouria impressa, Platysternon megacephalum) were the most frequently encountered species according to our interviewees. We conclude that, in order to enhance the conservation status of the turtle communities at the local level, it would be important (i) to increase the number of rangers patrolling the study area in the rainy season (from April to September) and (ii) to list the hunter's names in the villages surrounding the Bach Ma National Park and to convince them to sign an agreement with the local authorities to avoid hunting turtles within the Protected Area.

According to the IUCN, Southeast Asia is the area of the world with the highest number of threatened turtle species. The current status of chelonians is particularly catastrophic in Vietnam. However, there is still a lack of field data to unambiguously support this fact for a few species. To better understand the freshwater turtle diversity and eventually undertake efficient conservation actions, we conducted surveys with local fishers using standardized questionnaires in two independent river systems in northern Vietnam. A total of 112 questionnaires were administered to as many fishers in April and October 2022. We directly observed four sympatric freshwater species (Pelodiscus sinensis, Palea steindachneri, Mauremys sinensis and Sacalia quadriocellata) in Lao Cai and Yen Bai provinces, and two species (Pelodiscus sinensis and Palea steindachneri) in Bac Giang, Hai Duong, Thai Binh, and Hung Yen provinces. Based on the interviews, we added as possible the presence of two other species (Rafetus swinhoei and Pelochelys cantorii) in each of the two study areas. Moreover, we recorded for the first time in Vietnam, two wild individuals of an invasive alien species, the Common snapping turtle (Chelydra serpentina), confirming that the distribution and ecology of turtle species in Vietnam is poorly understood. Furthermore, recent photos (year 2019) of a 38 kg softshell turtle, possibly attributable to Rafetus swinhoei, were recorded from a restaurant in the area. In conclusion, interviews with local fishers have been found to be useful for exploring the likely presence and the local distribution of the various turtle species.

Although woody plant encroachment of tropical forest ecosystems has been related to altered disturbance regimes, its impacts on the nearest neighborhood structures and community phylogenetics are still poorly understood. Streblus macrophyllus is a light-demanding species during its early life stages and is shade-tolerant as a mature tree. S. macrophyllus can be found in tropical karst evergreen forests in northern Vietnam. It often regenerates at high densities in anthropogenic disturbed forest stands. To understand the structural patterns of disturbed forests encroached by S. macrophyllus at different abundance levels, three fully mapped 1-ha plots were established in Cuc Phuong National Park. Methods considering the phylogenetic community and nearest neighbor statistics were applied to identify how community structure changes during S. macrophyllus encroachment. Results showed that phylogenetic distance, phylogenetic diversity, and mean phylogenetic distance increased when species diversity increased and the abundance of S. macrophyllus decreased in forest communities. Net related index values were positive, which indicates a clustered phylogenetic structure among all sampled forest communities. S. macrophyllus trees were mixed well with heterospecifics and had regular to aggregated distributions, whereas the species showed evidence of being a strong competitor with its neighbors. Competition could be a major ecological process regulating forest communities encroached by S. macrophyllus. According to the forest disturbance effects, phylogenetic community properties showed the loss of phylogenetic relatedness when S. macrophyllus increased in abundance. To our knowledge, S. macrophyllus encroaches tropical rain forest communities as a disturbance-adapted species.