Forests are home to 80% of the world’s terrestrial biodiversity; globally, 1.6 billion people (nearly 25% of the world’s population) rely on forests (IUCN, 2021), with most of them (about 1.2 billion) using trees on farms to generate food and cash (MacDicken, 2015). This is the reason that forests are emerging as a key arena of action at the forefront of major global initiatives, i.e., Sustainable Development Goals (SDGs) and Aichi Biodiversity Targets of the Convention on Biological Diversity (Adams et al., 2004). Forests regulate ecosystems and bio-geochemical cycles, support biodiversity and livelihoods, and help to contribute to sustainable growth (MacDicken, 2015; IUCN, 2021). However, deforestation and forest degradation due to environmental change and anthropogenic disturbances disrupt the ecological functions, diversity, and delivery of ecosystem services (IUCN, 2014; Díaz et al., 2019; Soh et al., 2019; Bhatt et al., 2020; Wani et al., 2022). Globally, more than 3.2 billion people have been affected by land degradation and deforestation. Global Assessment of Land Degradation and Improvement (GLADA) reported that 24% of the land is degrading, 23% of broadleaved forests, and 19% of coniferous forests have been degraded (Bai et al., 2008). This assessment further reported that more than 2 billion people directly depend on these degrading areas for their livelihood, therefore, making them most vulnerable. Halting the loss and degradation of forest ecosystems and promoting their restoration have the potential to contribute over one-third of the total climate change mitigation that is required by 2030, to meet the objectives of the Paris Agreement (Palita et al., 2011; Brooks et al., 2012; Bonn Challenge, 2019; IUCN, 2021).

Forest restoration is considered a critical strategy for conserving global biodiversity and climate change mitigation (Bastin et al., 2019; Chazdon and Brancalion, 2019; IUCN, 2021; Wani et al., 2025). Restoration of degraded, deforested, and fragmented land has been globally recognised as an effective strategy for achieving the goal of biodiversity conservation and climate change mitigation (Díaz et al., 2015; Bonn Challenge, 2019). Ecological restoration and mainstreaming of the concept of ecosystem services will be critical if global society is to move toward sustainability. It was well reported that the restoration is successful only through people’s consultation and participation (Maikhuri et al., 1997; Negi et al., 2015; Iype et al., 2025). Large-scale failure of past efforts can be attributed to the lack of a participatory strategy to determine the essential needs of the local population and gain their cooperation (Meli et al., 2014; Wagley and Karki, 2020). Over the past two decades, ecological restoration, particularly forest landscape restoration (FLR), has increasingly been taken into consideration in decision-making processes and international studies, treaties, and conventions (Díaz et al., 2015; Bhattacharya et al., 2018; Bonn Challenge, 2019; Ashraf and Ahmad, 2024). FLR is considered worldwide as a powerful approach to recover ecological functionality and to improve human well-being in degraded and deforested landscapes (Sabogal et al., 2015; Brancalion and Chazdon, 2017; César et al., 2021). Ecosystem restoration is fundamental to achieving the Sustainable Development Goals (SDGs), mainly those on climate change, poverty eradication, food security, water, and biodiversity conservation (Aronson and Alexander, 2013; Bhattacharjee, 2020). This is the reason for declaring this decade (2020-2030) as the Decade of Ecosystem Restoration by the UN General Assembly.

Restoration of degraded land has been an essential activity on the agenda of the Government of India since the early 1980s, when India launched the Social Forestry Programme (SFP), followed by the more participatory Joint Forest Management (JFM) Programme. India joined the Bonn Challenge pledge in 2015 during the UNFCCC Conference of the Parties (COP) in Paris. Further, in the ‘Delhi Declaration’ during UNCCD CoP 14, India committed to the recovery of 26 million hectares of degraded land, and an additional eight million by 2030 (Bhattacharya et al., 2018; Bonn Challenge, 2019; UNCCD, 2019). Further, India has acted as an important stakeholder in shaping the mechanism of REDD⁺ (Reducing Emissions from Deforestation and Forest Degradation) by emphasising the role of conservation and sustainable forest management in mitigating carbon emissions (MoEF&CC, 2018). Among the world’s mountains, the Himalaya regulates the hydrological cycle, sustaining high levels of biodiversity and human well-being (Rawal et al., 2013, 2021; Chettri and Sharma, 2016; Anjum et al., 2023). Forest degradation and deforestation are considered a common process in the Himalayan region, which needs immediate implementation of restoration programmes and their long-term monitoring (Pandit et al., 2007; Alexander et al., 2016; Chakraborty et al., 2018; Negi et al., 2018a). Ecological restoration is an important tool for increasing biodiversity and carbon stock levels in human-altered ecosystems, which will help mitigate climate change impacts (Brudvig, 2011; Erbaugh et al., 2020; Jinger et al., 2023; Ali et al., 2024). Ecological restoration supports the plantation of native species for better survival and performance. Past studies reported that native species are ideal for restoring degraded forests/land due to their adaptability in a particular environment (Thomas et al., 2014; Lu et al., 2017). Therefore, the selection of plant species for the restoration programme is based on local demand and their eco-physiological attributes following past studies (Maikhuri et al., 1997; Negi et al., 2015). Further, the selection of bio-engineering (i.e., trenches, water harvesting tank, gully plugging, check dam), and measures for soil and water conservation for restoration were also highlighted in many studies. GBP-NIHE significantly contributes to environmental conservation and sustainability by developing restoration models in different parts of the Indian Himalaya. The present study attempts to (i) highlight the restoration activities at a successful restoration model, (ii) examine the impact of restoration activities on biodiversity conservation, and (iii) evaluate the social implications of ecological restoration in the western Himalaya.

Forest Landscape Restoration (FLR) emerged in 2000 as a novel approach to recover ecosystem services and strengthen human well-being in deforested and degraded areas (Sabogal et al., 2015; César et al., 2021). ‘Delhi Declaration’ during UNCCD CoP 14, India committed to bringing 13 million hectares of degraded land under restoration by 2020 and an additional 8 million hectares by 2030 is a challenge in the face of global climate change and rapidly increasing human population (Bhattacharya et al., 2018). However, to meet these targets, the successful restoration model with their community linkages and scientific inputs can become a candidate to accelerate restoration or the FLR process across the globe, particularly in the IHR (Bhattacharya et al., 2018; Bastin et al., 2019; Höhl et al., 2020; César et al., 2021). The successful restoration sites can contribute to Aichi Target 15 of the Convention on Biological Diversity, climate change mitigation, and the SDGs goal. Further, the role of forests as a carbon dioxide sink has received increasing attention since the adoption of the Kyoto Protocol to UNFCC in 1997 (Maniatis et al., 2019). It is well known that several restoration projects have been implemented under the FLR programme across the globe; this success depends on their monitoring and management. The success of past restoration projects remains poorly documented; this missed opportunity to learn from past experiences is essentially required for upscaling (Sabogal et al., 2015; Negi et al., 2022).

As a case, our restoration model has resulted in quantifiable improvement of the species richness, community composition, and carbon sequestration potential. Our study has provided an example of successful forest restoration in the Himalayan Mountain region, with 88 species successfully established with sufficient numbers of seedlings and saplings, which further supports that afforestation is an important measure for improving species composition, as also reported elsewhere (Guo et al., 2013; Osuri et al., 2019). Over the years, ‘Surya-Kunj’, which was a degraded slope, has been rehabilitated with around 190 species representing nearly 51% of the total tree species (372 species) of the western Himalaya (Bhatt et al., 2016). The present analysis showed regeneration in 88 species representing nearly 24% of total West Himalayan tree species, belonging to 61 families representing nearly 94% of West Himalayan tree families (Bhatt et al., 2016). Despite its extent, the family representation of tree species aptly reflects the site as an evolving restoration model of representative West Himalayan floral elements. People’s consultation and participation were important components of our restoration model; this motivated villagers for plantation activities and created awareness for biodiversity conservation, as reported in past studies (Maikhuri et al., 2000; Negi et al., 2015). The impacts of the restoration model are seen as the villagers adopted plantation activities on their private farmlands, and also in community-managed abandoned land. The institute has up-scaled the restoration activities in other areas of the IHR through its Regional Centre, engaging the community (please see Bhatt et al., 2020). Further, the institute has developed a few specific techniques for restoration in the IHR, including Sloping Watershed Environment Engineering Technology (SWEET), Agroforestry Model, Silvi-Pasture Development, Contour Hedgerow Farming System, and Bio-Engineering Measures (Bhatt et al., 2020). Taking advantage of these interventions, people across the IHR are implementing them in the restoration activities.

Planting native species is recommended globally for ecosystem restoration and improvement in genetic diversity in a particular ecosystem (Budiharta et al., 2014; Wani et al., 2025). Although the difference in survival of native and non-native species is too low to impact the restoration’s success in the present study. However, it is well known that native species are ideal for restoring degraded forests (Lu et al., 2017; Thomas et al., 2014; César et al., 2021). In addition, the ground layer of vegetation, particularly of shrubs, herbs, lichen, and bryophytes, was improved significantly in the restoration model (Joshi et al., 2014; Bhandari et al., 2019). Few endemic species like Trachycarpus takil, Meizotropis pellita, Pittosporum eriocarpum, etc., are unique to the restoration site. This site also has all five species of Oak, i.e., Quercus leucotrichophora, Q. semecarpifolia, Q. glauca, Q. floribunda, and Q. lanuginosa, that are reported from the western Himalaya. The regeneration and recruitment in the restoration model were quite good for many species. Natural regeneration of tree species has started, as reflected by the presence of seedlings and saplings of other species. It is reported that the presence of seed sources in the restoration site ensures the availability of propagules for seedling production (Budiharta et al., 2014; Uriarte and Chazdon, 2016; César et al., 2021). Simple engineering techniques and interventions adopted during the initial stage of implementation ensured soil stabilisation, prevented soil erosion, reduced runoff, and improved percolation of water at the restoration site, as also reported in previous studies (Schultz et al., 2012; Negi et al., 2015; Kremen and Merenlender, 2018).

Naturalisation of various plant species in the restoration site, especially wild edible plants, has provided the base for various fruit-eating and nectar-feeding birds and butterflies throughout the year; this further ensured the diversity of other faunal species, such as insects. The change in species richness of butterflies reflects improvement in habitat conditions. Birds are one among many forest-associated species that are facing the threat of habitat degradation; however, the population of birds increased in our restoration site. The Important Bird Area (IBA) programme of BirdLife International is a worldwide initiative to identify and protect the world’s birds (BirdLife International, 2021). Considering the four criteria used for designating a site for conservation, Criteria A1, in general, states that the regular presence of a Critically Endangered (CE) or Endangered (E) species, irrespective of population size, qualifies a site as an IBA (BirdLife International, 2016). Therefore, ‘Surya-Kunj with the regular presence of four threatened bird species, qualifies as an IBA under criteria A1. Further, ‘Surya-Kunj’ harbours avifaunal diversity that is comparable to the nearest IBA site (Binsar Wildlife Sanctuary; 166 spp.). Conservation of MP diversity in the ‘Surya-Kunj’ (i) provides base material for in-depth research on the phytochemical and genetic attributes of these MPs, (ii) develops reproducible propagation protocols using conventional and in vitro methods, (iii) cater to the need of locals by making available the elite planting material, and (iv) impart knowledge and build capacity of diverse stakeholder on conservation and sustainable utilisation of MPs. The richness of MPs initially increased from 20 in 1995 to over 90 plants in 2024, including RET species. In this way, the restoration site contributes to the ex-situ conservation of important RET species and is used as a genetic repository of MPs for mass multiplication. Reproducible propagation protocols have helped develop quality planting material to promote the cultivation and recovery/reintroduction of the selected species in their natural habitats.

Biodiversity conservation is widely practiced through the generation of awareness among diverse stakeholders. Considering the importance of education in conservation-related issues through non-formal means, various conservation education programmes have been organised in the present study, as done in the past by the Institute (Dhar et al., 2002). The conservation programme aimed to sensitise the young minds towards valuing biodiversity and its conservation, providing restoration as an example. The literature indicates that investments in restoration or FLR require good governance, a reliable policy environment, and reliable mechanisms to resolve stakeholder conflicts (Sabogal et al., 2015). IUCN and WRI created a Restoration Opportunities Assessment Methodology (ROAM) to help stakeholders what restoration activities provide the greatest ecological, social, and economic benefits in a particular area of degraded land (Hanson et al., 2015). Equitable climate mitigation and biodiversity conservation from forest restoration require the inclusion and participation of local communities (Brancalion et al., 2017; Loft et al., 2017; Pathak et al., 2021). Findings reveal that empowering the local community in restoration projects through technical training and equitable resource access reduces risks associated with community resource management. Our study demonstrated that restoration with community participation ensures biodiversity conservation, a steady flow of ecosystem goods, and a sense of awareness.

The three-decade-long restoration of the ‘Surya-Kunj’ site in the western Himalaya demonstrates that degraded landscapes can be successfully transformed into a self-sustaining, biodiversity-rich restoration model through a combination of scientific planning, community participation, and long-term commitment. The present study has demonstrated that the ecological restoration model has ample potential for biodiversity conservation, livelihood enhancement, and ecosystem-based services. The restored habitat now supports rich plant and faunal diversity, including medicinal plants, lichens, bryophytes, birds, butterflies, and insects, reflecting improved ecosystem complexity and resilience. Native Himalayan species showed better survival and regeneration than non-native species, underscoring the importance of prioritising local flora in restoration programs. Community involvement ensured protection and sustainable use of resources and facilitated replication of restoration practices in surrounding areas. Integrating conservation education further strengthened local stewardship and inspired broader environmental awareness. The ‘Surya-Kunj’ model offers a replicable and adaptable framework for ecological restoration in Himalayan and other mountain landscapes, contributing to biodiversity conservation, ecosystem service recovery, and sustainable livelihoods. Such successful ecological restoration projects are relevant to national and global environmental obligations like REDD+, CBD, and NDCs.