Floods in India are regular phenomenon that occurs in almost all parts of the country, causing significant damage to human lives, assets and ecosystem. Rapid change in weather patterns and decline in forest cover are considered to be the main reasons for frequent floods and associated damage to both human and natural system. Does forest cover help prevent frequent occurrences of flood and reduce flood related damages? Empirical evidences on the flood protective role of forest cover do not give a clear picture. While few studies find a strong link between forest cover and reduced flood incidence, several other studies from across the globe have challenged this traditional notion of the protective role of forest cover. The present study makes an attempt to examine the association between forest cover and flood damage using data from Indian states and the flood affected districts of the eastern Indian state of West Bengal, taking into account the social, economic, climatic and infrastructural parameters. The findings suggest that forest cover tends to reduce the extent of flood damage and hence has the ability to protect human lives and properties during flood events. It is essential that mitigation and adaptation strategies are shaped in a way that promotes preservation and regeneration of forest resources. Hence, the present study suggests adoption of ecosystem-based adaptation measures along with traditional hard structure flood prevention measures in order to prevent flood related damages effectively.
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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.
The choice of areas for nature conservation involves the attempt to maximize the benefits, whether by carrying out an economic activity or by the provision of Ecosystem Services. Studies are needed to improve the understanding of the effect of the extent and position along the watershed of restored areas on soil and water conservation. This study aimed to understand how different restoration strategies might reflect in soil conservation and sediment retention. Using InVEST tool, sediment transport was simulated in a small 12 km2 watershed (Posses River, in Southeast Brazil), where one of first Brazilian Payment for Ecosystem Services (PES) projects is being carried out, comparing different hypothetical restoration strategies. With 25% of restoration, sediment export decreased by 78% for riparian restoration, and 27% for the steepest slopes restoration. On the other hand, the decrease in soil loss was lower for riparian restoration, with a 16% decrease, while the steepest slopes restoration reduced it by 21%. This mismatch between the reduction of sediment export and soil loss was explained by the fact that forest not only reduces soil loss locally but also traps sediment arriving from the upper parts of the watershed. While the first mechanism is important to provide soil stability, decreasing the risk of landslip, and to maintain agricultural productivity, the second can improve water quality and decrease the risk of silting, with positive effects on the water reservoirs at the outlet of the watershed. This suggests that Riparian and the Steepest Slopes restoration strategies are complementary in the sense of preventing sediments from reaching the water bodies as well as protecting them at their origin (with the reduction of erosion), so it will be advisable to consider the two types of restoration.
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.
Raising interest in ‘nature-based solutions’ (NBS) has inspired attempts to organise their principles and qualities within comprehensive and internally consistent evaluation frameworks, so as to demonstrate the superior per- formance of ‘working with nature’. However, the proposed frameworks stop short of taking into account the changing conditions in which NBS are set to operate. Climate change, in particular, can alter ecosystems and their services, and may undermine the performance of green solutions that rely on them. We present here a ‘dy- namic’ assessment framework that explicitly accounts for the impact of climate change on the effectiveness of the proposed NBS. The framework is based on an innovative approach that integrates system analysis and backcasting. Although it has not yet been applied to the NBS context, backcasting is well-suited to seize the trans- formational character of NBS, as it encourages ‘breakthrough’ leaps rather than incremental improvements. Our framework factors in the multifunctional character of NBS and is designed to capture associated direct benefits/ costs and co-benefits/costs. It is meant to be applied ex ante to ideally support the choice between innovative NBS and traditional options, in an effort to respond to the societal challenges identified by the EU Research & Innova- tion agenda on the environment.
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.
Planted and invading non-native plant species can alter fire regimes through changes in fuel loads and in the structure and continuity of fuels, potentially modifying the flammability of native plant communities. Such changes are not easily predicted and deserve system-specific studies. In several regions of the southern hemisphere, exotic pines have been extensively planted in native treeless areas for forestry purposes and have subsequently invaded the native environments. However, studies evaluating alterations in flammability caused by pines in Patagonia are scarce. In the forest-steppe ecotone of northwestern Patagonia, we evaluated fine fuels structure and simulated fire behavior in the native shrubby steppe, pine plantations, pine invasions, and mechanically removed invasions to establish the relative ecological vulnerability of these forestry and invasion scenarios to fire. We found that pine plantations and their subsequent invasion in the Patagonian shrubby steppe produced sharp changes in fine fuel amount and its vertical and horizontal continuity. These changes in fuel properties have the potential to affect fire behavior, increasing fire intensity by almost 30 times. Pruning of basal branches in plantations may substantially reduce fire hazard by lowering the probability of fire crowning, and mechanical removal of invasion seems effective in restoring original fuel structure in the native community. The current expansion of pine plantations and subsequent invasions acting synergistically with climate warming and increased human ignitions warrant a highly vulnerable landscape in the near future for northwestern Patagonia if no management actions are undertaken.
New sustainable, cost-effective solutions are urgently needed for river management since conventional practices have posed serious ecological threats on streams, rivers and the surrounding riparian areas. Besides addressing the societal needs e.g. for flood management, river management should increasingly address the ecosystem requirements for improved water quality and biodiversity. We argue that it is not feasible to solve existing and future river management challenges with intensive restoration projects. Instead, we believe that less resource-intensive solutions using natural channel processes and features, including vegetation, should be investigated. Besides directly supporting biota, aquatic and riparian vegetation traps, takes up and helps to process nutrients and harmful substances, and thus this paper emphasizes vegetation as a tool for nature-based solutions (NBS) in river management. We synthesize findings from key literature, showing that the fate of substances in channel systems is largely controlled by abiotic and biotic processes facilitated and modified by vegetation, including flow hydrodynamics, channel morphology, and sediment transport. Subsequently, we demonstrate how vegetation can be incorporated into channel designs, focusing on a two-stage (compound) design to improve resilience to flooding, control the transport of substances, and enhance the ecological status. As a conclusion, clever use and maintenance of vegetation present an unused potential to obtain large-scale positive environmental impacts in rivers and streams experiencing anthropogenic pressures.
Coastal fisheries provide staple food and sources of livelihood in Pacific Island countries, and securing a sustainable supply is recognised as a critical priority for nutrition security. This study sought to better understand the role of fish for Pacific Island communities during disasters and in disaster recovery. To evaluate community impacts and responses after natural disasters, focus group discussions were held with men and women groups at ten sites across Shefa, Tafea, Malampa and Sanma provinces in Vanuatu. The combined impacts of category 5 Tropical Cyclone Pam (TC-Pam) in March 2015 and prolonged El-Niño induced drought have had a profound impact across much of Vanuatu. Terrestrial systems had been disproportionately impacted with substantial shortages in drinking water, garden crops, cash crops and damage to infrastructure. Localized impacts were noted on marine environments from TC-Pam and the drought, along with an earthquake that uplifted reef and destroyed fishing grounds in Malampa province. Communities in Malampa and Shefa provinces also noted a crown-of-thorns outbreak that caused coral mortality. The significant reduction in terrestrial-based food and income generation capacity generally led to increased reliance on marine resources to cope and a shift in diets from local garden food to rice. However, limited market access, lack of fishing skills and technology in many sectors of the community reduced the capacity for marine resources to support recovery. A flexible management approach allowed protected areas and species to be utilized as reservoirs of food and income when temporarily opened to assist recovery. These findings illustrate that fish and fisheries management is at the center of disaster preparedness and relief strategies in remote Pacific Island communities. High physical capital (e.g. infrastructure, water tanks and strong dwellings) is key for disaster preparedness, but supporting community social capital for the purpose of natural resource management and human capital for diverse adaptation skills can also improve community resilience. Recognizing the humanitarian value that well managed fisheries resources and skilled fishers can play to disaster relief adds another dimension to the imperative of improving management of coastal fisheries and aligning policies across sectors.
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.
Background Enhancing water provision services is a common target in forest restoration projects worldwide due to growing concerns over freshwater scarcity. However, whether or not forest cover expansion or restoration can improve water provision services is still unclear and highly disputed. Purpose The goal of this review is to provide a balanced and impartial assessment of the impacts of forest restoration and forest cover expansion on water yields as informed by the scientific literature. Potential sources of bias on the results of papers published are also examined. Data sources English, Spanish and Portuguese peer-review articles in Agricola, CAB Abstracts, ISI Web of Science, JSTOR, Google Scholar, and SciELO. Databases were searched through 2015. Search terms Intervention terms included forest restoration, regeneration/regrowth, forest second-growth, forestation/afforestation, and forestry. Target terms included water yield/quantity, stream-flow, discharge, channel runoff, and annual flow. Study selection and eligibility criteria Articles were pre-selected based on key words in the title, abstract or text. Eligible articles addressed relevant interventions and targets and included quantitative information. Results Most studies reported decreases in water yields following the intervention, while other hydrological benefits have been observed. However, relatively few studies focused specifically on forest restoration, especially with native species, and/or on projects done at large spatial or temporal scales. Information is especially limited for the humid tropics and subtropics. Conclusions and implications of key findings While most studies reported a decrease in water yields, meta-analyses from a sub-set of studies suggest the potential influence of temporal and/or spatial scales on the outcomes of forest cover expansion or restoration projects. Given the many other benefits of forest restoration, improving our understanding of when and why forest restoration can lead to recovery of water yields is crucial to help improve positive outcomes and prevent unintended consequences. Our study identifies the critical types of studies and associated measurements needed.
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.
Resource managers increasingly seek to implement cost-effective-watershed restoration plans for multiple ecosystem service benefits. Using locally adapted ecosystem service tools and historical management costs, we quantified spatially explicit management costs and benefits (in terms of groundwater recharge and landscape flammability) to assist a state agency in evaluating cobenefits for a predefined restoration scenario (focused on biodiversity benefits) and to prioritize an expanded restoration scenario in the state-managed Pu’u Wa’awa’a watershed (Hawai’i) now and under the Representative Concentration Pathway (RCP) 8.5 midcentury climate scenario. Restoring all available -areas increases recharge by similar to 1.74 million m(3)/yr (5% of recharge over the entire watershed) under the current climate and does not meaningfully change recharge under RCP 8.5 midcentury, whereas climate change decreases recharge by similar to 50%. For landscape flammability, climate change increases the median and maximum probability of fire occurrence across all land use scenarios, and full restoration results in the greatest reduction in landscape flammability under both current and RCP 8.5 midcentury climate scenarios. We demonstrate that location and type of forest restoration influence overall cost-effectiveness of – restoration, providing insights for landscape planning for ecosystem services under a limited budget. Across all scenarios, capturing potential benefits at low elevations requires greater expenditures ($13,161/ha) than at high elevations ($5,501/ha) due mainly to the substantial costs of removing Pennisetum setaceum (fountain grass), the dominant land cover below 1,000 m. If management focuses on groundwater recharge only, the most cost-effective areas occur at high elevations (>1,000 m), with ample fog interception, although recharge benefits decline across the landscape under RCP 8.5 midcentury. Focusing instead on cost-effective landscape flammability reduction as the primary management objective shifts emphasis toward dry low-elevation areas under the current climate. However, under the RCP 8.5 midcentury scenario, the most cost-effective areas for flammability management shift toward higher elevations with greater potential overlap with recharge benefits.
Future scenarios indicate that growing human encroachment on coasts, more frequent and stronger storms and sea level rise will result in worsening coastal squeeze. In consequence, human lives, property and infrastructure, as well as ecosystem services, will increasingly be threatened. It is therefore vital to find the means to maintain or increase the resilience and resistance of coastal zones. As an alternative to hard infrastructure, ecosystem-based coastal defense strategies have been recommended as better and more sustainable solutions. Thus, the goal of this study wasto understand the interaction of dune plants with waves, dunes and humans. We used a pantropical beach plant (Ipomoea pes-caprae) and performed 24 wave flume experiments with two beach-dune profiles, four densities of vegetation cover, and three storm regimes. We also tested tolerance to burial in seed germination and seedling growth and finally explored the impact of tourism on Ipomoea. Erosion regimes of collision and overwash were observed in the dune profiles with a berm, whereas swash and overwash regimes were observed when no berm was present. Plant cover prevented overwash and thereby erosion of the landward side of the dune. Positive responses in seeds and seedlings of Ipomoea to burial by sand enable this plant to act as a dune builder. In conditions with low tourism, Ipomoea seems to be more affected by seasonal and meteorological conditions than by trampling. These responses increase further the potential for coastal protection of Ipomoea and, thus, such an ecosystem-based protective structure can be self-sustainable.
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.
In the international climate policy arena, Ecosystem-based Adaptation (EbA) has become the preferred adaptation approach to climate change in the least developed and developing countries. Its perceived strength lies in the premise that adaptation strategies need to address both ecosystems and livelihoods simultaneously, given these are crucially intertwined and both under a threat from climate change. While EbA has certainly made progress as an adaptation approach, a lack of understanding still exists how EbA approaches contribute to ‘effective’ adaptation, including the circumstances where they face constraints and limits. Furthermore, implementation of EbA approaches ideally requires a level of understanding about ecosystem structure, productivity and dynamics, and how these are affected by climate change and other direct anthropogenic stressors, that are rarely available in developing countries. This paper aimed to synthesise the current knowledge in the emerging body of EbA specific literature on the kinds of constraints that hamper the use of EbA. Our analysis examined the following constraints: economic and financial, governance and institutional, social and cultural, knowledge constraints and gaps, and physical and biological constraints and limits. The identified constraints demonstrate the complexities in developing, implementing, monitoring and evaluating EbA and propose significant further areas of research, including the need to provide well-documented case studies of EbA, which crystallise the main lessons learned such as practical challenges in designing and implementing EbA projects and research programs.
Coral reefs can provide significant coastal protection benefits to people and property. Here we show that the annual expected damages from flooding would double, and costs from frequent storms would triple without reefs. For 100-year storm events, flood damages would increase by 91% to $US 272 billion without reefs. The countries with the most to gain from reef management are Indonesia, Philippines, Malaysia, Mexico, and Cuba; annual expected flood savings exceed $400 M for each of these nations. Sea-level rise will increase flood risk, but substantial impacts could happen from reef loss alone without better near-term management. We provide a global, process-based valuation of an ecosystem service across an entire marine biome at (sub)national levels. These spatially explicit benefits inform critical risk and environmental management decisions, and the expected benefits can be directly considered by governments (e.g., national accounts, recovery plans) and businesses (e.g., insurance).
Forest management in several boreal countries is strongly focused on conifers because they are more productive, the technical quality of their stems is better, and their wood fibers are longer as compared to broadleaves. Favoring conifers in forest management leads to simple forest structures with low resilience and diversity. Such forests are risky in the face of climate change and fluctuating timber prices. Climate change increases the vitality of many forest pests and pathogens such as Heterobasidion spp. and Ips typographus L. which attack mainly spruce. Wind damages are also increasing because of a shorter period of frozen soil to provide a firm anchorage against storms. Wind-thrown trees serve as starting points for bark beetle outbreaks. Increasing the proportion of broadleaved species might alleviate some of these problems. This study predicts the long-term (150 years) consequences of current conifer-oriented forest management in two forest areas, and compared this management with silvicultural strategies that promote mixed forests and broadleaved species. The results show that, in the absence of damages, conifer-oriented forestry would lead to 5-10% higher timber yields and carbon sequestration. The somewhat lower carbon sequestration of broadleaved forests was counteracted by their higher albedo (reflectance). Mixed and broadleaf forests were better providers of recreational amenities. Species diversity was much higher in mixed stand and broadleaf-oriented silviculture at stand and forest levels. The analysis indicates that conifer-oriented forest management produces rather small and uncertain economic benefits at a high cost in resilience and diversity.
Coastal communities in tropical environments are at increasing risk from both environmental degradation and climate change and require urgent local adaptation action. Evidences show coral reefs play a critical role in wave attenuation but relatively little direct connection has been drawn between these effects and impacts on shorelines. Reefs are rarely assessed for their coastal protection service and thus not managed for their infrastructure benefits, while widespread damage and degradation continues. This paper presents a systematic approach to assess the protective role of coral reefs and to examine solutions based on the reef’s influence on wave propagation patterns. Portions of the shoreline of Grenville Bay, Grenada, have seen acute shoreline erosion and coastal flooding. This paper (i) analyzes the historical changes in the shoreline and the local marine, (ii) assess the role of coral reefs in shoreline positioning through a shoreline equilibrium model first applied to coral reef environments, and (iii) design and begin implementation of a reef-based solution to reduce erosion and flooding. Coastline changes in the bay over the past 6 decades are analyzed from bathymetry and benthic surveys, historical imagery, historical wave and sea level data and modeling of wave dynamics. The analysis shows that, at present, the healthy and well-developed coral reefs system in the southern bay keeps the shoreline in equilibrium and stable, whereas reef degradation in the northern bay is linked with severe coastal erosion. A comparison of wave energy modeling for past bathymetry indicates that degradation of the coral reefs better explains erosion than changes in climate and historical sea level rise. Using this knowledge on how reefs affect the hydrodynamics, a reef restoration solution is designed and studied to ameliorate the coastal erosion and flooding. A characteristic design provides a modular design that can meet specific engineering, ecological and implementation criteria. Four pilot units were implemented in 2015 and are currently being field-tested. This paper presents one of the few existing examples available to date of a reef restoration project designed and engineered to deliver risk reduction benefits. The case study shows how engineering and ecology can work together in community-based adaptation. Our findings are particularly important for Small Island States on the front lines of climate change, who have the most to gain from protecting and managing coral reefs as coastal infrastructure.
There is growing interest in promoting the use of Ecosystem-based Adaptation (EbA) practices to help smallholder farmers adapt to climate change, however there is limited information on how commonly these practices are used by smallholder farmers and what factors influence their use. Using participatory mapping and field surveys, we examined the prevalence and characteristics of EbA practices on 300 smallholder coffee and maize farmers in six landscapes in Central America and explored the socioeconomic and biophysical factors associated with their use. The prevalence of individual EbA practices varied across smallholder farms. Common EbA practices included live fences, home gardens, shade trees in coffee plantations, and dispersed trees in maize fields. We found a mean of 3.8 EbA practices per farm. Factors that were correlated with the total number of EbA practices on farms included the mean area of coffee plantations, farmer age, farmer experience, the farm type and the landscape in which farms were located. Factors associated with the presence or characteristics of individual EbA practices included the size of coffee plantations, farmer experience, farmer education, land tenure, landscape and farm type. Our analysis suggests that many smallholder farmers in Central America are already using certain EbA practices, but there is still scope for greater implementation. Policy makers, donors and technicians can encourage the broader use of EbA by smallholder farmers by facilitating farmer-to-farmer exchanges to share knowledge on EbA implementation, assessing the effectiveness of EbA practices in delivering adaptation benefits, and tailoring EbA policies and programs for smallholder farmers in different socioeconomic and biophysical contexts.
In view of past environmental degradation and anticipated climate change impacts, we assessed the potential for ecosystem-based adaptation in the Murray-Darling Basin, Australia. In a workshop with staff from three Catchment Management Authorities (CMAs) who had jurisdiction over three sub-basins, as well as technical experts, nine adaptation options were identified that ranged from environmental flows, restoring river channel habitat, reoperating infrastructure and controlling invasive species. A Catchment Adaptation Framework was developed and used to assess and compare these adaptation options with each of the CMAs, drawing on interviews with their key stakeholders, to identify the risks, benefits and costs. We found that ecosystem-based adaptation can augment catchment management programs and requires investment in a suite of different but complementary measures to lower risk. Our research found institutional challenges in implementing this approach, including the complexities of multi-agency management, constricting legal requirements, narrow funding arrangements, under-developed institutional capacity, difficulties of implementing catchment-scale programs on private property and the need to adhere to community expectations. These institutional issues are ubiquitous internationally and point to the wider issues of providing sufficient management capacity to support adaptation. The Catchment Adaptation Framework presented here enables river basin managers to systematically assess the adaptation options to better inform their decision-making.
Drawing on information presented throughout this book, this chapter identifies key knowledge gaps relating to climate and climate-change effects on agriculture, forestry, and wetlands. It further points toward research needed to make management of these ecosystems part of a solution, by identifying gaps in the current understanding of biosphere-based adaptation or mitigation strategies. The list presented here is only concerned with climate change — biosphere interactions, and with questions of land use or management where they intersect with this topic. It cannot tackle the much larger subject of “global change,” or strategies for GHG mitigation that are not biosphere based. Further, it focuses on science needed to support economic or policy decision, without making reference to specific market or legislative tools. It also makes no attempt to include knowledge gaps relating to the development of economic or policy mechanisms needed to make biosphere-based GHG mitigation a functional and attractive option. For an introduction to this field, the reader is referred to Chapter 19.
Farming freshwater prawns with fish in rice fields is widespread in the coastal region of southwest Bangladesh because of favourable resources and ecological conditions. This article provides an overview of an ecosystem-based approach to integrated prawn-fish-rice farming in southwest Bangladesh. The practice of prawn and fish farming in rice fields is a form of integrated aquaculture-agriculture, which provides a wide range of social, economic and environmental benefits. Integrated prawn-fish-rice farming plays an important role in the economy of Bangladesh, earning foreign exchange and increasing food production. However, this unique farming system in coastal Bangladesh is particularly vulnerable to climate change. We suggest that community-based adaptation strategies must be developed to cope with the challenges. We propose that integrated prawn-fish-rice farming could be relocated from the coastal region to less vulnerable inland areas, but caution that this will require appropriate adaptation strategies and an enabling institutional environment.
Forests are sources of wood, non-timber forest products and ecosystems services and goods that benefit society as a whole, and are especially important to rural livelihoods. Forest landscape restoration (forest-landscape-restoration:Forest landscape restoration) has been proposed as a way to counteract deforestation and reconcile the production of ecosystem services and goods with conservation and development goals. But limited evidence indicates how large-scale forest restoration could contribute to improving local livelihoods. Here, we present a conceptual framework to analyze the effects of large-scale restoration on local livelihoods, and use it to review the scientific literature and reduce this knowledge gap. Most of the literature referred to case studies (89%), largely concentrated in China (49%). The main theme explored was income, followed by livelihoods diversification, off-farm employment opportunities, poverty reduction, equity and the provision of timber and energy as ecosystem services. Nearly 60 percent of the papers discussed the importance of governance systems to socioeconomic outcomes. The reforestation/restoration programs and policies investigated in the studies had mixed socioeconomic effects on local livelihoods depending on other variables, such as availability of off-farm jobs, household characteristics, land productivity, land tenure, and markets for forest products and ecosystem services. We conclude that the effects of large-scale restoration initiatives on local livelihoods may vary due to several factors and is still not clear for many situations; therefore, monitoring over time with clear indicators is needed.