As the severity of the triple challenges of global inequality, climate change and biodiversity loss becomes clearer, governments and international development institutions must find effective policy instruments to respond. We examine the potential of social assistance policies in this context. Social assistance refers to transfers to poor, vulnerable and marginalized groups to reduce their vulnerability and livelihood risks, and to enhance their rights and status. Substantial public funds support social assistance programmes globally. Collectively, lower- and middle-income countries spend approximately 1.5% of their GDP on social assistance annually. We focus on the potential of paid employment schemes to promote effective ecosystem stewardship. Available evidence suggests such programmes can offer multiple benefits in terms of improvements in local ecosystems and natural capital, carbon sequestration and local biodiversity conservation. We review evidence from three key case studies: in India (the Mahatma Gandhi National Rural Employment Guarantee Scheme), Ethiopia (the Productive Safety Nets Programme) and Mexico (the Temporary Employment Programme). We conclude that, to realize the potential of employment-based social assistance for ecosystem benefits it will be necessary to address two challenges: first, the weak design and maintenance of local public works outputs in many schemes, and second, the concern that social protection schemes may become less effective if they are overburdened with additional objectives. Overcoming these challenges requires an evolution of institutional systems for delivering social assistance to enable a more effective combination of social and environmental objectives. This article is part of the theme issue ‘Climate change and ecosystems: threats, opportunities and solutions’.
NbS Target: Climate Change Mitigation
Climate change mitigation
Better land stewardship is needed to achieve the Paris Agreement’s temperature goal, particularly in the tropics, where greenhouse gas emissions from the destruction of ecosystems are largest, and where the potential for additional land carbon storage is greatest. As countries enhance their nationally determined contributions (NDCs) to the Paris Agreement, confusion persists about the potential contribution of better land stewardship to meeting the Agreement’s goal to hold global warming below 2°C. We assess cost-effective tropical country-level potential of natural climate solutions (NCS)—protection, improved management and restoration of ecosystems—to deliver climate mitigation linked with sustainable development goals (SDGs). We identify groups of countries with distinctive NCS portfolios, and we explore factors (governance, financial capacity) influencing the feasibility of unlocking national NCS potential. Cost-effective tropical NCS offers globally significant climate mitigation in the coming decades (6.56 Pg CO2e yr−1 at less than 100 US$ per Mg CO2e). In half of the tropical countries, cost-effective NCS could mitigate over half of national emissions. In more than a quarter of tropical countries, cost-effective NCS potential is greater than national emissions. We identify countries where, with international financing and political will, NCS can cost-effectively deliver the majority of enhanced NDCs while transforming national economies and contributing to SDGs. This article is part of the theme issue ‘Climate change and ecosystems: threats, opportunities and solutions’.
Seagrass meadows are an important wetland habitat that have been degraded globally but have an important carbon storage role. In order to expand the restoration of these productive and biodiverse habitats methods are required that can be used for large scale habitat creation across a range of environmental conditions. The spreading of seagrass seeds has been proven to be a successful method for restoring seagrass around the world, however in places where tidal range is large such methods become limited by resultant water movements. Here we describe and test a method for deploying seagrass seeds of the species Zostera marina over large scales using a new, simple method “Bags of Seagrass Seeds Line (BoSSLine).” This method involved planting seeds and sediment using natural fiber hessian bags deployed along strings anchored onto the seabed. When deployed in a suitable environment 94% of bags developed mature seagrass shoots, unfortunately one site subjected to a large storm event resulted in sediment burial of the bags and no seed germination. Bags were filled with 100 seeds with each leading to the development of 2.37 ± 2.41 mature shoots (206 ± 87 mm in length) 10 months after planting. The method was proven successful however the experiments illustrated the need to ensure habitat suitability prior to their use. Low seed success rate was comparable to other restoration studies, however further trials are recommended to ensure ways to improve this rate. In conclusion, this study provides evidence for an effective, simple method “Bags of Seagrass Seeds Line (BoSSLine)” for deploying seeds of the seagrass Zostera marina over large scales.
Peatlands are wetland ecosystems that accumulate dead organic matter (i.e., peat) when plant litter production outpaces peat decay, usually under conditions of frequent or continuous waterlogging. Collectively, global peatlands store vast amounts of carbon (C), equaling if not exceeding the amount of C in the Earth’s vegetation; they also encompass a remarkable diversity of forms, from the frozen palsa mires of the northern subarctic to the lush swamp forests of the tropics, each with their own characteristic range of fauna and flora. In this review we explain what peatlands are, how they form, and the contribution that peatland science can make to our understanding of global change. We explore the variety in formation, shape, vegetation type, and chemistry of peatlands across the globe and stress the fundamental features that are common to all peat-forming ecosystems. We consider the impacts that past, present, and future environmental changes, including anthropogenic disturbances, have had and will have on peatland systems, particularly in terms of their important roles in C storage and the provision of ecosystem services. The most widespread uses of peatlands today are for forestry and agriculture, both of which require drainage that results in globally significant emissions of carbon dioxide (CO2), a greenhouse gas (GHG). Climatic drying and drainage also increase the risk of peat fires, which are a further source of GHG emissions [CO2 and methane (CH4)] to the atmosphere, as well as causing negative human health and socioeconomic impacts. We conclude our review by explaining the roles that paleoecological, experimental, and modeling studies can play in allowing us to build a more secure understanding of how peatlands function, how they will respond to future climate- and land-management-related disturbances, and how best we can improve their resilience in a changing world.
Nature-based solutions (NbS) is the latest contribution to the green concept family. NbS is defined as actions based in nature addressing societal challenges. In this study, we lean on the concept boundary object, broken down into three analytical categories: use, core ideas and granularities, to explore the cohesive and fragmenting powers of the NbS concept, and discuss its future role in green space governance. The study is based on a structured, qualitative review of 112 scientific peer-reviewed publications that use the term NbS. Most publications are from 2017 or later, highlighting the novelty of the NbS concept. The concept has a strong footing in the European urban context. Flood mitigation and functional ecosystems and biodiversity conservation are the most targeted sustainability goals in the publications, and a diversity of solutions are considered. There is a close link between the NbS concept, green infrastructure, and the ecosystem service concept, indicating a path dependency in its uptake and use. The publications demonstrate a low level of integration of the NbS concept (i.e. it is commonly used as a buzz word). Most empirical studies focus solely on environmental benefits delivered by NbS, and few studies assess social, economic, and environmental benefits together, which is a central ambition of the concept. We conclude that the NbS concept is working on the boundaries between different scientific disciplines and between science and policy. Depending on how the research community deals with identified temporal, epistemological and ontological granularities, we conclude that the concept has three potential developmental pathways; broader and deeper, biased with stickiness to older green concepts and an empty buzz word.
There is growing international interest in better managing soils to increase soil organic carbon (SOC) content to contribute to climate change mitigation, to enhance resilience to climate change and to underpin food security, through initiatives such as international ‘4p1000’ initiative and the FAO’s Global assessment of SOC sequestration potential (GSOCseq) programme. Since SOC content of soils cannot be easily measured, a key barrier to implementing programmes to increase SOC at large scale, is the need for credible and reliable measurement/monitoring, reporting and verification (MRV) platforms, both for national reporting and for emissions trading. Without such platforms, investments could be considered risky. In this paper, we review methods and challenges of measuring SOC change directly in soils, before examining some recent novel developments that show promise for quantifying SOC. We describe how repeat soil surveys are used to estimate changes in SOC over time, and how long‐term experiments and space‐for‐time substitution sites can serve as sources of knowledge and can be used to test models, and as potential benchmark sites in global frameworks to estimate SOC change. We briefly consider models that can be used to simulate and project change in SOC and examine the MRV platforms for SOC change already in use in various countries/regions. In the final section, we bring together the various components described in this review, to describe a new vision for a global framework for MRV of SOC change, to support national and international initiatives seeking to effect change in the way we manage our soils.
Intact Forest Landscapes (IFLs) are critical strongholds for the environmental services that they provide, not least for their role in climate protection. On the basis of information about the distributions of IFLs and Indigenous Peoples’ lands, we examined the importance of these areas for conserving the world’s remaining intact forests. We determined that at least 36% of IFLs are within Indigenous Peoples’ lands, making these areas crucial to the mitigation action needed to avoid catastrophic climate change. We also provide evidence that IFL loss rates have been considerably lower on Indigenous Peoples’ lands than on other lands, although these forests are still vulnerable to clearing and other threats. World governments must recognize Indigenous Peoples’ rights, including land tenure rights, to ensure that Indigenous Peoples play active roles in decision‐making processes that affect IFLs on their lands. Such recognition is critical given the urgent need to reduce deforestation rates in the face of escalating climate change and global biodiversity loss.
Regional and global assessments periodically update what we know, and highlight what remains to be known, about the link- ages between people and nature that both define and depend upon the state of the environment. To guide research that better informs policy and practice, we systematically synthesize knowledge gaps from recent assessments of four regions of the globe and three key themes by the Intergovernmental Science-Policy Platform for Biodiversity and Ecosystem Services. We assess their relevance to global sustainability goals and trace their evolution relative to those identified in the Millennium Ecosystem Assessment. We found that global sustainability goals cannot be achieved without improved knowledge on feedbacks between social and ecological systems, effectiveness of governance systems and the influence of institutions on the social distribution of ecosystem services. These top research priorities have persisted for the 14 years since the Millennium Ecosystem Assessment. Our analysis also reveals limited understanding of the role of indigenous and local knowledge in sustaining nature’s benefits to people. Our findings contribute to a policy-relevant and solution-oriented agenda for global, long-term social-ecological research.
Land-use change disturbs the function of peatland as a natural carbon sink and triggers high GHG emissions. Nevertheless, historical trends and future trajectories of GHG budgets from soil do not explicitly include peatlands. Here, we provide an estimate of the past and future role of global peatlands as either a source or sink of GHGs based on scenario timelines of land conversion. Between 1850 and 2015, temperate and boreal regions lost 26.7 million ha, and tropical regions 24.7 million ha, of natural peatland. By 2100, peatland conversion in tropical regions might increase to 36.3 million ha. Cumulative emissions from drained sites reached 80 ± 20 PgCO2e in 2015 and will add up to 249 ± 38 Pg by 2100. At the same time, the number of intact sites accumulating peat will decline. In 1960 the global peatland biome turned from a net sink into a net source of soil-derived GHGs. Annual back-conversion of most of the drained area would render peatlands GHG neutral, whereas emissions from peatland may comprise 12–41% of the GHG emission budget for keeping global warming below +1.5 to +2 °C without rehabilitation.
Earth is approaching environmental thresholds that, if crossed, will create serious disruptions to ecosystems, economies, and society. To avoid the devastating effects of climate change and biodiversity loss, humanity must protect and restore native ecosystems. International conventions and organizations support forest restoration as a method for mitigating hazardous environmental shifts, but questions remain as to where and how to focus such restoration efforts. On page 76 of this issue, Bastin et al. describe a new approach that advances our understanding of global tree distribution.
The Global Deal for Nature (GDN) is a time-bound, science-driven plan to save the diversity and abundance of life on Earth. Pairing the GDN and the Paris Climate Agreement would avoid catastrophic climate change, conserve species, and secure essential ecosystem services. New findings give urgency to this union: Less than half of the terrestrial realm is intact, yet conserving all native ecosystems—coupled with energy transition measures—will be required to remain below a 1.5°C rise in average global temperature. The GDN targets 30% of Earth to be formally protected and an additional 20% designated as climate stabilization areas, by 2030, to stay below 1.5°C. We highlight the 67% of terrestrial ecoregions that can meet 30% protection, thereby reducing extinction threats and carbon emissions from natural reservoirs. Freshwater and marine targets included here extend the GDN to all realms and provide a pathway to ensuring a more livable biosphere.
‘Ocean Cities’ of the Pacific are where urban landscapes and seascapes meet, where built and natural environments interface, and where human behaviour and urban development have profound impacts on both terrestrial and marine ecosystems. Ocean Cities are at the forefront of climate change consequences, urbanisation challenges, and other development pressures. This article discusses the potential for nature-based solutions (NbS), including those focused on ecosystem services, in Pacific Small Island Developing States (SIDS) as a response to climate change, population growth, and urbanisation. Attention is directed to identifying the benefits of NbS and case-studies from Pacific SIDS, and if not available regionally, further afield. The article provides focus on possible barriers to implementation of NbS in a Pacific SIDS context and potential policy responses to these. Conclusions are threefold: (i) addressing interlinked ecological, climate, and human wellbeing issues in an integrated, ocean-focused and climate-responsive manner is vital for sustainable development in island systems; (ii) NbS can provide significant human wellbeing and biodiversity benefits in this context; and (iii) Pacific Ocean Cities, with a significant body of relevant traditional knowledge and emerging NbS experience, can inform global understanding of how to address converging urbanisation and climate change issues in Ocean Cities.
The role of forests in climate change mitigation is well documented. However, little is known about the importance of forests to adaptation in response to climate change, and its integration with mitigation options to cushion social and biophysical systems from the impacts of climate change. This paper examines pathways for harmonizing forest-related climate change adaptation and mitigation in francophone Africa covering Burkina Faso, Côte d’Ivoire, Democratic Republic of Congo, Madagascar and Cameroon. Qualitative and quantitative research approaches were employed in this study. It was found that wood energy savings, afforestation, reforestation, promotion of community forests, agro-silvipastoral schemes and urban forestry schemes were the most identified interventions with a potential of climate change adaptation and mitigation outcomes. In this regard, mainstreaming forests into adaptation and mitigation policies in the context of NDCs is critical if the benefits from forests and trees outside forests are to be realized in Francophone Africa.
Over 140 Mha of restoration commitments have been pledged across the global tropics, yet guidance is needed to identify those landscapes where implementation is likely to provide the greatest potential benefits and cost-effective outcomes. By overlaying seven recent, peer-reviewed spatial datasets as proxies for socioenvironmental benefits and feasibility of restoration, we identified restoration opportunities (areas with higher potential return of benefits and feasibility) in lowland tropical rainforest landscapes. We found restoration opportunities throughout the tropics. Areas scoring in the top 10% (i.e., restoration hotspots) are located largely within conservation hotspots (88%) and in countries committed to the Bonn Challenge (73%), a global effort to restore 350 Mha by 2030. However, restoration hotspots represented only a small portion (19.1%) of the Key Biodiversity Area network. Concentrating restoration investments in landscapes with high benefits and feasibility would maximize the potential to mitigate anthropogenic impacts and improve human well-being.
We currently face both an extinction and a biome crisis embedded in a changing climate. Many biodiverse ecosystems are being lost at far higher rates than they are being protected or ecologically restored. At the same time, natural climate solutions offer opportunities to restore biodiversity while mitigating climate change. The Bonn Challenge is a U.N. programme to restore biodiversity and mitigate climate change through restoration of the world’s degraded landscapes. It provides an unprecedented chance for ecological restoration to become a linchpin tool for addressing many environmental issues. Unfortunately, the Forest and Landscape Restoration programme that underpins the Bonn Challenge, as its name suggests, remains focused on trees and forests, despite rising evidence that many non-forest ecosystems also offer strong restoration potential for biodiversity and climate mitigation. We see a need for restoration to step back to be more inclusive of different ecosystem types and to step up to provide integrated scienti c knowledge to inform large-scale restoration. Stepping back and up will require assessments of where to restore what species, with recognition that in many landscapes multiple habitat types should be restored. In the process, trade-offs in the delivery of different ecosystem services (e.g. carbon, biodiversity, water, albedo, livestock forage) should be clearly addressed. We recommend that biodiversity safeguards be included in policy and implemented in practice, to avoid undermining the biophysical relationships that provide ecosystem resilience to climate change. For ecological restoration to contribute to international policy goals will require integrated large-scale science that works across biome boundaries.
Land-based greenhouse gas removal (GGR) options include afforestation or reforestation (AR), wetland restoration, soil carbon sequestration (SCS), biochar, terrestrial enhanced weathering (TEW), and bioenergy with carbon capture and storage (BECCS). We assess the opportunities and risks associated with these options through the lens of their potential impacts on ecosystems services (Nature’s Contributions to People; NCPs) and the United Nations Sustainable Development Goals (SDGs). We find that all land-based GGR options contribute positively to at least some NCPs and SDGs. Wetland restoration and SCS almost exclusively deliver positive impacts. A few GGR options, such as afforestation, BECCS, and biochar potentially impact negatively some NCPs and SDGs, particularly when implemented at scale, largely through competition for land. For those that present risks or are least understood, more research is required, and demonstration projects need to proceed with caution. For options that present low risks and provide cobenefits, implementation can proceed more rapidly following no-regrets principles.
Despite substantial increases in the scope and magnitude of biodiversity conservation and ecological restoration, there remains ongoing degradation of natural resources that adversely affects both biodiversity and human well- being. Nature-based Solutions (NbS) can be an effective framework for reversing this trend, by increasing the alignment between conservation and sustainable development objectives. However, unless there is clarity on its evolution, definition and principles, and relationship with related approaches, it will not be possible to develop evidence-based standards and guidelines, or to implement, assess, improve and upscale NbS interventions globally. In order to address this gap, we present the definition and principles underpinning the NbS framework, recently adopted by the International Union for Conservation of Nature, and compare it to (1) the Ecosystem Approach that was the foundation for developing the NbS definitional framework, and (2) four specific eco- system-based approaches (Forest Landscape Restoration, Ecosystem-based Adaptation, Ecological Restoration and Protected Areas) that can be considered as falling under the NbS framework. Although we found substantial alignment between NbS principles and the principles of the other frameworks, three of the eight NbS principles stand out from other approaches: NbS can be implemented alone or in an integrated manner with other solutions; NbS should be applied at a landscape scale; and, NbS are integral to the overall design of policies, measures and actions, to address societal challenges. Reversely, concepts such as adaptive management/governance, effectiveness, uncertainty, multi-stakeholder participation, and temporal scale are present in other frameworks but not captured at all or detailed enough in the NbS principles. This critical analysis of the strengths and weaknesses of the NbS principles can inform the review and revision of principles supporting specific types of NbS (such as the approaches reviewed here), as well as serve as the foundation for the development of standards for the successful implementation of NbS.
Urban nature has the potential to improve air and water quality, mitigate flooding, enhance physical and mental health, and promote social and cultural well-being. However, the value of urban ecosystem services remains highly uncertain, especially across the diverse social, ecological and technological contexts represented in cities around the world. We review and synthesize research on the contextual factors that moderate the value and equitable distribution of ten of the most commonly cited urban ecosystem services. Our work helps to identify strategies to more efficiently, effectively and equitably implement nature-based solutions.
Limiting climate warming to <2°C requires increased mitigation efforts, including land stewardship, whose potential in the United States is poorly understood. We quantified the potential of natural climate solutions (NCS)—21 conservation, restoration, and improved land management interventions on natural and agricultural lands—to increase carbon storage and avoid greenhouse gas emissions in the United States. We found a maximum potential of 1.2 (0.9 to 1.6) Pg CO2e year−1, the equivalent of 21% of current net annual emissions of the United States. At current carbon market prices (USD 10 per Mg CO2e), 299 Tg CO2e year−1 could be achieved. NCS would also provide air and water filtration, flood control, soil health, wildlife habitat, and climate resilience benefits.
Intensively used coastal zones often know a history of hard defense structures to prevent erosion and protect infrastructure against floods. The interruption of sand transport between sea, beach and dunes however causes a domination of late successional stages such as dune shrub. With the decline of young, dynamic vegetation types, a change occurs in the provision of ecosystem services. In spite of the growing awareness on the role of dune dynamics to support human well-being and biodiversity, redynamisation of dunes is rarely implemented in coastal zone management. It has been argued in research documents that this may be caused by a failure to make those benefits tangible and specific. This study aims to underpin the added value of dynamic versus fixed dunes. Five different ecosystem services in a case-study in Belgium were quantified based on (compound) indicators and expressed in monetary units. The value of a natural, dynamic dune system covering the entire gradient of dune succession and dominated by young successional stages was compared with the value of a fixed dune system dominated by late successional stages. The results indicate that a dynamic dune complex may create up to ∼50% higher economic benefits, and that the main benefits are on account of recreation and coastal safety maintenance. The results underpin the statement that we can only continue benefitting from the services dunes provide if we accept their mobile nature, but that redynamisation requires a site-specific feasibility analysis.
Constructed wetlands (CW) are effective in treating wastewater, particularly in settings that require low tech-nology and low maintenance as operational constraints. Biomass harvested from CW can be used as a renewableenergy source and treated effluent can provide irrigation for agricultural uses. Biomass yields for four selectedwetland plants in CW, namelyPhragmitesspp.,Typhaspp.,A. donax,andC. papyrus, ranged from an average ofabout 1500g of dry mass per square meter (g/m2) forTyphaspp., up to 6000g/m2forA.donax. The energy yieldfor direct combustion of these plants occupied a narrow range, averaging about 18 megajoules per kilogram ofdry mass (MJ/kg) for all plant types, a comparable amount toAcacia spp. Methane yields varied from about170–360L of methane (normalised to standard conditions) per kilogram of dry mass (LN/kg). 1m2of CWplanted withA. donaxcan produce on average 110MJ through direct combustion or 1660L of methane frombiogas production. In a village of 200 people the biomass from a CW planted withTyphaspp. can reduce cookingfuel needs by 4–55% and therefore save up to 12ha of forest per year. The water footprint of these plants wasmeasured as the percent loss in water in the CW from evapotranspiration (ET). Under a fixed set of assumptionson climate and operation, the water used through ET, the CW could deliver from 64% to 76% of the influentwater for subsequent use. In summary, CW have the potential to offset energy and irrigation needs at scalesranging from small communities to peri-urban areas. Constructed wetlands used to treat wastewater have thepotential to provide a sustainable bioenergy source without placing burdens on water resources or displacingother food or energy crops.
The Mediterranean evergreen oak coppices of Southern Europe are increasingly vulnerable to drought because of both the ongoing climate change that increases drought length and intensity, and the lack of forest management that induces a structural aging of the stands. Decreasing stand density through thinning has been widely regarded as a means to improve the resistance of evergreen oak forests to climate change by decreasing the competition for water amongst the remaining stems. Data from a 30-years thinning experiment, that includes a control and four thinning intensity treatments (from 25% to 80% of basal area removed), in a coppiced holm oak (Quercus ilex L.) forest of southern France, was used to quantify the effects of thinning on stem growth. Building on the ‘sink limitation’ paradigm, which proposes that tree growth is controlled by phenology and climatic constraints and decoupled from carbon assimilation, we investigated if the effect of thinning on stem growth was explained by a delayed drought-induced growth cessation. Using a water balance model, we simulated the date of drought-induced growth cessation, previously found to correspond to the day of the year when water potential drops below a threshold of -1.1 MPa, and used it to predict growth in the different treatments of the thinning experiment. Thinning increased long-term growth at the stem level but decreased the wood biomass at the stand level. Decreasing stem density, and hence the leaf area index, was simulated to delay the date of drought-induced growth cessation. A growth model based on the date of growth cessation explained 85% of the effect of thinning on stem growth over the 30-year period of the study, and 95% for the first five years after thinning. The canopy density for which the effect of thinning is the most beneficial was found to maximize the growth duration without lifting completely the water limitation in summer. Moderate thinning had a sustained beneficial effect on the growth of all stem size classes, whereas stronger thinning intensities increased the size asymmetry of competition and their overall effect dropped faster. Our simple predictive model based on the simulation of the water balance as a function of stand density opens the way to providing management guidelines for the optimization of tree density as a function of water limitation in Mediterranean evergreen woodlands.
Ecological infrastructure (EI) refers to ecosystems that deliver services to society, functioning as a nature-based equivalent of, or complement to, built infrastructure. EI is critical for socio-economic development, supporting a suite of development imperatives at local, national and international scales. This paper presents the myriad of ways that EI supports sustainable development, using South Africa and the South African National Development Plan as a case study, linking to the Sustainable Development Goals on a global level. We show the need for EI across numerous development and sustainability issues, including food security, water provision, and poverty alleviation. A strategic and multi-sectoral approach to EI investment is essential for allocating scarce public and private resources for achieving economic and social-ecological priorities. Opportunities to unlock investment in EI, both internationally and on the national level, are identified. This includes leveraging private sector investment into landscape management and integrating the costs of managing EI into public sectors that benefit directly from ecosystem services, such as the water sector and infrastructure development. Additionally, investing in EI also aligns well with international development and climate change funds. Investment in EI from a range of innovative sources supports global and national development, while complementing other development investments.
Forest loss and degradation globally has resulted in declines in multiple ecosystem services and reduced habitat for biodiversity. Forest landscape restoration offers an opportunity to mitigate these losses, conserve biodiversity, and improve human well-being. As part of the Bonn Challenge, a global effort to restore 350 million hectares of deforested and degraded land by 2030, over 30 countries have recently made commitments to national forest landscape restoration. In order to achieve these goals, decision-makers require information on the potential benefits and costs of forest landscape restoration to efficiently target investments. In response to this need, we developed an approach using a suite of ecosystem service mapping tools and a multi-objective spatial optimization technique that enables decision-makers to estimate the potential benefits and opportunity costs of restoration, visualize tradeoffs associated with meeting multiple objectives, and prioritize where restoration could deliver the greatest benefits. We demonstrate the potential of this approach in Uganda, one of the nations committed to the Bonn Challenge. Using maps of the potential benefits and costs of restoration and efficiency frontiers for optimal restoration scenarios, we were able to communicate how ecosystem services benefits vary spatially across the country and how different weights on ecosystem services objectives can affect the allocation of restoration across Uganda. This work provides a generalizable approach to improve investments in forest landscape restoration and illuminates the tradeoffs associated with alternative restoration strategies.
Rio Doce watershed has centuries of land degradation and it was the main victim of the worst environmental disaster in Brazil’s history. This process of deforestation and soil erosion could be significantly mitigated if compliance to the new Brazilian Native Vegetation Protection Law (NVPL) would be ensured. Here, we show how the percentage of forest kept in areas of permanent preservation (APP) required by the NVPL drives the overall resilience and resistance of the entire Rio Doce watershed and how it contributes to the national restoration commitments. We used water quality as a proxy for watershed resilience and resistance and we found that compliance to NVPL would require restoration of about 716 thousand hectares of riverine forest across the watershed. We found that increased forested areas improved watershed resistance and resilience during the rainy and dry seasons, respectively. Our estimates suggest that the implementation of the NVPL could improve water quality, in addition to removing 14 Gt CO2 yr−1 ha−1 from the atmosphere. At this scale, the forest restoration effort would represent 6% of Brazil’s restoration commitment. Financial feasibility of such a restoration enterprise is also achievable; at the highest possible estimate, it would compromise about 59% of the total fund proposed by the mining companies responsible for the accident. Given the low socioeconomic indicators of this basin, intervention should be designed so as to improve local livelihoods and, therefore, contribute to local adaptation and sustainable development.