The forests in the Republic of Korea (ROK) successfully recovered through the national forestation program as did the ecosystem services associated with them. With this positive experience, it is instructive to investigate the economic viability of the forestation program. In this study, we estimated the changes in the key ecosystem services (disaster risk reduction (DRR), carbon sequestration, water yield enhancement, and soil erosion control; 1971–2010) and the monetary investment of the forestation (1960–2010) in the ROK, at a national scale. These benefits and costs were estimated by biophysical and monetary approaches, using statistical data from several public organizations, including the Korea Forest Service and the Korea Meteorological Administration, combined with model simulation. All monetary values were converted to the present value in 2010. The net present value and the benefit-cost ratio of the forestation program were 54,316 million $ and 5.84 in 2010, respectively, in the long-term. The break-even point of the extensive investment on the forestation appeared within two decades. In particular, the enhancements of DRR and carbon sequestration were substantial. This economic viability was ensured by the subsidiary implementations (e.g., participation of villagers, shifting energy source, and administrative regulation). Early and extensive investment in forestation is recommended for economic viability and successful implementation of the program. Our study is expected to provide a scientific rationale for implementing forestation program in other countries.
NbS Approach: Disaster Risk Reduction
Ecosystem-based disaster risk reduction
Since the Indian Ocean tsunami on 26 December 2004, there have been continuous efforts to upgrade the (tsunami) early warning systems as well as their accessibility in local and regional places in South and Southeast Asia. Meanwhile, the protection offered by coastal vegetation like mangroves to the people, property and physical landscape was also recognized and prioritized by both public and private authorities at various governance levels. As more than 90% of the Sri Lankan coastline is vulnerable to water-related impacts and existing bioshields like mangroves are potentially able to protect less than one-third of it, if at all they are in good condition, an attempt was made to build knowledge on the other potential natural barriers along the coast. In this context, a ca. 2 km belt of the entire coast was digitized, classified and assessed for vulnerability in relation to the existing land-use/cover. First, a visually interpreted land-use/cover map comprising 16 classes was developed using Google Earth imagery (Landsat-5, 2003). Second, based on the Global Digital Elevation Model data from the ASTER satellite, the land-use/cover map was further re-classified for elevation demarcation into waterless, run-up and flooded areas. And finally, both vulnerable and less vulnerable areas were identified by taking into account the average wave heights that the 2004 tsunami reached in the country (North: 5.5 m, South: 7 m, East: 5 m and West: 3.75 m). Among the selected areas studied, Jaffna and Kaluvanchikudy-Komari are found to be vulnerable and, Trincomalee, Yala and Puttalam are less vulnerable. While vulnerability was largely associated with the conditions devoid of natural barriers, the less vulnerable areas had mangroves, Casuarina, dense vegetation and/or sand dunes as land cover, all of which might prove effective against ocean surges. However, these land cover types should never be considered as providing full protection against the type of threats that can be expected. As the present study provides only base-line information on island-wide vulnerability of areas to water-related impacts, further investigation and validation along similar research lines are needed to establish a blueprint for future preparedness.
Louisiana is in the midst of a land loss crisis that has claimed more than 4800 km(2) since the 1930s. Unless aggressive, large-scale action is taken, Louisiana could lose an additional 4500 km(2) in the next 50 years, resulting in a projected increase in annual damages from hurricane storm surge flooding of more than $23 billion. Louisiana’s 2012 Coastal Master Plan is a long-term plan with clear economic, social, and environmental benefits, such as decreasing potential damages from storm surge by $5.3 billion to $18 billion. Implementation of projects in the master plan should result in no net loss of land after 20 years and an annual net gain of land after 30 years. To develop the plan, the Coastal Protection and Restoration Authority (CPRA) utilized a state-of-the-art systems approach to coastal planning and a science-based decision-making process that resulted in a funding- and resource-constrained plan that makes the greatest progress toward achieving a sustainable coast. A series of integrated, coastwide predictive models were developed to provide data for a new planning tool used to identify the suite of projects that would make the greatest progress toward meeting the master plan objectives while considering uncertainties in future environmental conditions. Recognizing that the success of the plan hinges on stakeholder support, as well as science, the CPRA also implemented a comprehensive outreach plan to obtain input and feedback from key stakeholders and the public. The resulting plan recommends a specific list of restoration and protection projects and has achieved widespread support.
Extensive cultivation of rubber plantations in Xishuangbanna in southwest (SW) China has resulted in negative hydrological consequences, particularly drought, during the pronounced dry season. Although rubber-tea agroforestry is regarded as the most successful agroforestry system for improving the sustainability of rubber agriculture and environmental conservation, plant water use patterns and their related interactions have rarely been examined in such systems. How do coexisting plants compete and share water under water deficit remains to be explored. Therefore, we used stable isotope (delta D and delta O-18) methods to determine the spatial water use patterns of both rubber trees and tea trees in a rubber-tea agroforestry system during the pronounced dry season and explored the movement of soil water in this system. The results of the MixSIAR model (a Bayesian mixing model) indicated that tea trees primarily uptake water from the 5-30 cm soil layer (40.3%, on average), and rubber trees primarily uptake water from the 30-80 cm soil layer (35.3%, on average) and absorb soil water evenly along slopes during the dry season. These results suggest that rubber trees and tea trees have different but complementary water use patterns. We also observed that the soil of the uphill and downhill tea rows contained much more water; however, the collaborative hydraulic redistribution in the studied agroforestry system could redistribute the soil water along the slope and below the ground well. Therefore, soil drought on terraces can be alleviated during the dry season. Our results confirmed that the tea tree is an appropriate crop for intercropping with rubber trees when considering water sharing and water management and provided a practical analysis of water use benefits from a rubber agroforestry system during drought stress.
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.
Around 0 AD, the Rhine-Meuse estuary in the southwest of the Netherlands was a typical coastal plain estuary. Drainage of peatland and land subsidence behind the dunes later caused the sea to penetrate into the land. Most of the peat was eroded, and by 1000 AD the so-called Delta area had turned into a landscape of large estuaries and intertidal zones. Rotterdam developed from a small fishing village on the banks of the tidal river “Nieuwe Maas” from the 14th century onwards into the largest seaport of Europe in 2013. The Rotterdam harbour area situated in the northern part of the Delta area includes the former Europoort harbour, and is nowadays known as Rijnmond. The hydrology of the area is controlled by the drainage regime of the sluices in the Haringvliet barrier that was constructed as part of the “Delta Works” project to protect the southwest of the Netherlands against storm surges. The sluices are opened at slack tide to discharge river water to the sea and are always closed at flood tide. As a baseline study for environmental and ecological reconstruction and development, we describe in detail the loss of intertidal soft sediment ecotopes due to land reclamation, harbour development and river training works (straightening of the navigational channel) in the tidal rivers, and the expansion of hard substrate ecotopes (quay walls, groynes, training walls, riprap, concrete, stones etc.) in the Rijnmond area in the 19th and 20th centuries. Within 135 years, more than 99% of the original 4775 ha of characteristic pristine soft sediment estuarine ecotopes have disappeared. In the same period, 338 ha of hard intertidal substrate zone was constructed. Such trends can also be observed in harbour areas elsewhere, and have ecological and environmental consequences for estuarine areas in particular. Restoration of soft substrate estuarine ecotopes can be achieved by opening the Haringvliet Sluices at both ebb and flood tide, which would restore large-scale estuarine dynamics to the northern part of the Rhine-Meuse estuarine system. This will have a highly favourable effect on many ecosystem services. The Dutch division of the Word Wild Life Fund has launched a new proposal for a safer and more attractive South-West Delta area. It comprises the reopening of the sea inlets such as the Haringvliet by removing the barriers, and building climateproof dikes in combination with natural wetlands. In case of storm surges, the hinterland could be protected with a new generation of barriers that do not hamper the free transport of sediment, tides and animals. Based on 30 ecosystem services or subservices, it was calculated that opening the Haringvliet inlet would lead to an increase in Total Economic Value (TEV) of at least 500 million Euro per year. The costs of removing old barriers and the construction of new ones was not included in the calculations.
Selection of areas for restoration should be based on cost-effectiveness analysis to attain the maximum benefit with a limited budget and overcome the traditional ad hoc allocation of funds for restoration projects. Restoration projects need to be planned on the basis of ecological knowledge and economic and social constraints. We devised a novel approach for selecting cost-effective areas for restoration on the basis of biodiversity and potential provision of 3 ecosystem services: carbon storage, water depuration, and coastal protection. We used Marxan, a spatial prioritization tool, to balance the provision of ecosystem services against the cost of restoration. We tested this approach in a mangrove ecosystem in the Caribbean. Our approach efficiently selected restoration areas that at low cost were compatible with biodiversity targets and that maximized the provision of one or more ecosystem services. Choosing areas for restoration of mangroves on the basis carbon storage potential, largely guaranteed the restoration of biodiversity and other ecosystem services
Traditionally, actions taken to reduce vulnerability to beach erosion have been based on protecting economic resources, recreational activities and human lives. Hard infrastructure for coastal protection has proven effective, but the side effects have been called into question, given that making the coastal system more rigid alters the natural dynamics, degrades environmental services and damages the landscape. Ecosystem based coastal defence strategies are now seen as a more environmentally friendly alternative which can maintain and even increase the resilience and resistance of coastal zones. This work aims to improve the understanding of the behaviour of nature-based coastal defences by analysing the morphodynamic response of a dune-beach system with vegetation to storms. Small scale tests were performed in which beach profiles with natural dune vegetation were exposed to high energy waves. Free surface elevation and velocity profiles were recorded during the tests and the profile evolution was measured at the end of each experiment. 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. Retarding erosion time seems to be the most relevant morphological effect of the dune vegetation, which gives a slight, but relevant, contribution to the resilience and resistance of the beach profile. In turn, the wave breaking point is displaced seawards and bed velocities close to the shoreline are lower when vegetation is present, both of which explain the protective role of vegetation on the beach profile. To develop a numerical tool capable of reproducing the morphological evolution of the beach profiles tested, the CSHORE model was calibrated and validated for the laboratory data finding good correlation.
This paper offers a different framework for managing Mediterranean drought carob-tree orchard ecosystems. Two dry-farming systems were compared during two consecutive years: pure productive orchards and mixed orchards in a total of 360 mature trees distributed by 18 plots with areas of 0.55 and 0.30 ha per plot, respectively. Carob, fig, almond and olive trees compose mixed orchards. Trees of the mixed orchards were more productive than those of pure orchards. The main problem of both systems was the large variability and the low fruit production due to non-bearing trees, inducing unfavorable economic returns. Yield varied between 7.7 and 28.5 kg tree(-1) respectively in pure and mixed orchards. In this paper we propose to use carbon sequestration calculations as an added benefit to farmers. A carbon stocking model estimation was established, based on trunk diameters of different trees. We depicted two management scenarios based on fruits production and carbon sequestration incomes: a low value scenario, using mean fruit production, and a high valuable scenario based on the hypothesis that all trees reached its potential maximum. Since under dry-farming systems fruit production irregularity is still a pendent problem, mixed orchards may offer a potential higher revenue, while maintaining higher crop diversification and whole biodiversity. C sequestration benefit, as here we purpose, may represent 125-300 % of income, respectively under low or high valuable scenario. Thus, CO2 equivalent is a novel ecological economic incentive that may potentiate a new income for farmers while assuring carob ecosystem services.
Ecosystem-based approaches have proven effective and efficient in reducing disaster risks while ensuring continued benefits to people from ecosystem services. In this article, a new concept of Ecosystem-based Disaster Risk Reduction (Eco-DRR) for enhancing social-ecological resilience is proposed, based on analysis of several case studies. Field studies in developing countries such as Ghana and Myanmar have shown the benefits of Eco-DRR as implemented by local communities. These projects improve local livelihoods and social-ecological resilience. In Japan, after the massive damage from the 11 March 2011, Great East Japan earthquake and tsunami, ecosystem-based approaches were an important element of the national government’s DRR efforts. Analysis of these cases shows that Eco-DRR is a socially, economically and environmentally sustainable tool for DRR that creates new value for a region. It also shows the importance of multi-stakeholder participation in the process of promoting Eco-DRR. It is likely to become even more important in the future, as a means for addressing the increase in disasters resulting from climate and ecosystem change as well as demographic change. The contribution of Eco-DRR to maintaining and restoring ecosystems is particularly valuable for countries where there is reduced capacity for land management, as currently occurring in Japan due to rapid population decline and aging.
Coastal saltmarsh ecosystems occupy only a small percentage of Earth’s land surface, yet contribute a wide range of ecosystem services that have significant global economic and societal value. These environments currently face significant challenges associated with climate change, sea level rise, development and water quality deterioration and are consequently the focus of a range of management schemes. Increasingly, soft engineering techniques such as managed realignment (MR) are being employed to restore and recreate these environments, driven primarily by the need for habitat (re)creation and sustainable coastal flood defence. Such restoration schemes also have the potential to provide additional ecosystem services including climate regulation and waste processing. However, these sites have frequently been physically impacted by their previous land use and there is a lack of understanding of how this ‘disturbance’ impacts the delivery of ecosystem services or of the complex linkages between ecological, physical and biogeochemical processes in restored systems. Through the exploration of current data this paper determines that hydrological, geomorphological and hydrodynamic functioning of restored sites may be significantly impaired with respects to natural ‘undisturbed’ systems and that links between morphology, sediment structure, hydrology and solute transfer are poorly understood. This has consequences for the delivery of seeds, the provision of abiotic conditions suitable for plant growth, the development of microhabitats and the cycling of nutrients/contaminants and may impact the delivery of ecosystem services including biodiversity, climate regulation and waste processing. This calls for a change in our approach to research in these environments with a need for integrated, interdisciplinary studies over a range of spatial and temporal scales incorporating both intensive and extensive research design.
Stormwater wetlands (CSWs) have become one of the more popular SCMs, offering a hybrid between larger detention technologies such as wet ponds and newer green infrastructure technologies. A well-functioning stormwater wetland will be a resilient, diverse ecosystem that includes many plant and animal species. This research looks to investigate whether or not wetlands need regular maintenance to sustain their treatment capacity. The research site is located in River Bend, NC. Flow-weighted samples, rainfall, and hydrologic data are being collected at both the inlet and outlet from April 2012 – April 2013, aiming a minimum of 15 storms spaced throughout the year. Monitoring of phosphorus deposition consists of taking soil samples and analyzing for Soil Test Phosphorous. These monitoring results will be compared with the results of a study that was conducted at the same site for a one-year period immediately following construction completion. This will allow researchers to see the effects of no maintenance plan (or activity) and time on wetland performance in removing phosphorus and achieving other wetland performance goals. Vegetation in a CSW is essential for nutrient removal and thermal pollution reduction. However, a portion of the storage volume designed to retain the water quality event is occupied by vegetation, which may result in the CSW being undersized from a hydrologic perspective – especially in unmaintained, mature systems. The fraction of the volume associated with vegetation mass was unknown, and designers have been unsure as to (1) how they should account for volume occupied by vegetation and (2) whether this was a significant design issue. Twelve stormwater wetlands and one hybrid wet pond in North Carolina were sampled to assess their percent vegetative occupancy by volume. A conservative recommended factor of safety is 1.025. Species-specific factors of safety (FOS) were also calculated; at the 30 cm temporary pool elevation, the Iris (Iris spp.) FOS was highest at 1.020 and the mixed vegetation FOS was lowest at 1.005. When designing a wetland, a more specific FOS may be calculated using a weighted average of the FOS for each species in the planting plan. The outcomes of this research allow designers to account for the volume taken up by emergent wetland vegetation; however, the uncertainty in other factors such as discrepancies between designed and as-built bathymetry probably have a greater impact on the design volume loss when compared with vegetation occupancy (<2%). © 2013 American Society of Civil Engineers.