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471.
《Marine Policy》2017
Since Hurricane Sandy, there has been heightened attention to increasing the resilience of coastal communities to extreme events, including storm protection provided by coastal ecosystems. Storm protection benefits (SPB) are the ability of ecosystems, including wetlands, reefs, and beaches/dunes, to attenuate waves and storm surge. SPB are a topic of growing interest in the scientific and policy spheres, including discussions of how to incorporate SPB into existing policies. As an engine for restoration and a leading mechanism for the evaluation of ecosystem services, Natural Resource Damage Assessment (NRDA) provides a platform for better internalizing this and other services into decision-making particularly using Habitat Equivalency Analysis (HEA). HEA does not explicitly account for impacts to ecosystem services that flow from one habitat to an adjacent one. This study examines a hypothetical case study of an oil spill that impacts a marsh with resulting impacts on SPB to the adjacent upland forest. To more fully assess these impacts, a “nested HEA” was developed which accounts for cross-habitat ecosystem service flows. The nested HEA captures the impacts of the marsh loss on the forest due to wave and saltwater intrusion that would not be captured by a traditional HEA. By adapting the HEA approach with a nested HEA, NRDA could quantify direct ecosystem services losses as well as additional cross-service flows between habitats. However, additional data are needed in order to perform a nested HEA, and in the case of SPB, location-specific data likely will be needed to appropriately specify the model. 相似文献
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473.
Mountain regions are an important regulator in the global water cycle through their disproportionate water contribution. Often referred to as the “Water Towers of the World”, mountains contribute 40%–60% of the world's annual surface flow. Shade is a common feature in mountains, where complex terrain cycles land surfaces in and out of shadows over daily and seasonal scales, which can impact water use. This study investigated the turbulent water and carbon dioxide (CO2) fluxes during the snow-free period in a subalpine wetland in the Canadian Rocky Mountains, from 7 June to 10 September 2018. Shading had a significant and substantial effect on water and CO2 fluxes at our site. When considering data from the entire study period, each hourly increase of shade per day reduced evapotranspiration (ET) and gross primary production (GPP) by 0.42 mm and 0.77 g C m?2, equivalent to 17% and 15% per day, respectively. However, the variability in shading changed throughout the study, it was stable to start and increased towards the end. Only during the peak growing season, the site experienced days with both stable and increasing shade. During this time, we found that shade, caused by the local complex terrain, reduced ET and potentially increased GPP, likely due to enhanced diffuse radiation. The overall result was greater water use efficiency during periods of increased shading in the peak growing season. These findings suggest that shaded subalpine wetlands can store large volumes of water for late season runoff and are productive through short growing seasons. 相似文献