Welcome to PAP/RAC Mediterranean Coastal Alert! This newsletter is regularly updated monthly. It contains abstracts of selected current articles and archives on various environmental themes, in particular those dealing with all aspects of coastal issues. The selection is made from the articles published in the leading international scientific journals. This newsletter is an excellent way of keeping you updated with coastal studies and processes.
At three coastal dune sites at the island of Hiddensee, north-east Germany, vegetation cover was mapped during 2002 and compared to vegetation surveys from the late 1980s and 1930s. Abiotic and biotic factors, which have been identified as being critical for coastal dunes in former studies such as disturbance, salt spray or nutrient availability, were measured. Grazing and land-use history were reviewed by literature and interviews. Tall graminoid communities, mainly Carex arenaria, are a common vegetation unit today. Development, distribution of these dominances and possible causes for its occurrence have not been analysed. Generally, older successional vegetation units increased and pioneer stages decreased from the 1930s until 2002. At the geologically youngest site, the southern dunes, grass encroachment by Carex arenaria was highest (ca. 50% cover in 2002), and age and density of trees lower than at the older, central dunes. Land-use changes such as decrease in grazing pressure, additional feeding of livestock, increase in coastal protection measures and subsequent decrease in shifting sands as well as varying availability of groundwater and amount of salt spray are relevant factors for vegetation changes in coastal dunes over the past 70 years. Site-specific land-use differences such as livestock density and land-use history have a stronger influence than atmospheric N-pollution on the vegetation composition of these acidic, coastal dunes under low to moderate N-deposition loads of 6–8 kg N ha−1 yr−1.
Source: E. S. Remke and I. Blindow (2010); “Site specific factors have an overriding impact on Baltic dune vegetation change under low to moderate N-deposition - a case study from Hiddensee island”, Journal of Coastal Conservation (2011), Volume 15, No. 1, pages: 87 – 97; Received: 14 April 2010; Revised: 18 August 2010; Accepted: 19 August 2010; Published online: 24 September 2010, under DOI: 10.1007/s11852-010-0123-2.
This study aimed at the ecological-economic valuation of the Potengi estuary mangrove wetlands, based on the integration of spatial data (mangrove forest coverage map, Nautical Chart, Environmental Sensitivity Chart) with data from literature on the biogeochemistry of nitrogen (N), phosphorus (P), and heavy metals in the mangrove estuary wetland Potengi) and field verification data (topographic profile of mangrove forest, GPS routes obtained in the field in the touristy sightseeing areas and plots of mariculture). The ecological and economic valuation of the services performed by the Potengi estuary mangrove wetlands, mainly as biogeochemical barrier for the transport of P, N and heavy metals in tropical coastal areas, were obtained just as if the retention of those elements was necessary by Wastewater Treatment Plants (WTP) with Stabilization Ponds, typical in the estuary, and Zeolitic plant, respectively. Closer to real scenarios were observed for obtaining the values of these ecological services, such as the release of the P, N and heavy metals in domestic and industrial sewage in the estuary, the capability of dilution and the influence of the tides in the estuary. The tourism potential of the Potengi estuary mangrove wetlands were assessed according to the current forms of use, and potential of aquaculture through the main types of farming in mangrove areas. For these ecological services, considerable values were obtained of about USS15,500/ha, such as costs of implementation and construction of sewage treatment plants, as well as costs of sewage treatment plants. Nearly US$ 12.500 / ha amount each year from tourism and aquaculture income, demonstrating the economic viability of the Potengi estuary mangrove wetlands conservation.
Source: F. E. S. Souza and C. A. Ramos e Silva (2010); “Ecological and economic valuation of the Potengi estuary mangrove wetlands (NE, Brazil) using ancillary spatial data“, Journal of Coastal Conservation (2011), Volume 15, No. 1, pages: 195 – 206; Received: 1 April 2010; Revised: 5 August 2010; Accepted: 5 October 2010; Published online: 20 October 2010, under DOI: 10.1007/s11852-010-0133-0.
Because air - water and water - air interfaces are equally refractive, cloud droplets and microbubbles dispersed in bodies of water reflect sunlight in much the same way. The lifetime of sunlight-reflecting microbubbles, and hence the scale on which they may be applied, depends on Stokes Law and the influence of ambient or added surfactants. Small bubbles backscatter light more efficiently than large ones, opening the possibility of using highly dilute micron-radius hydrosols to substantially brighten surface waters. Such microbubbles can noticeably increase water surface reflectivity, even at volume fractions of parts per million and such loadings can be created at an energy cost as low as J m − 2 to initiate and mW m − 2 to sustain. Increasing water albedo in this way can reduce solar energy absorption by as much as 100 W m − 2, potentially reducing equilibrium temperatures of standing water bodies by several Kelvins. While aerosols injected into the stratosphere tend to alter climate globally, hydrosols can be used to modulate surface albedo, locally and reversibly, without risk of degrading the ozone layer or altering the color of the sky. The low energy cost of microbubbles suggests a new approach to solar radiation management in water conservation and geoengineering: Don’t dim the Sun; Brighten the water.
Keywords: Hydrosols; Solar radiation management; Water conservation; Geoengineering.
Source: R. Seitz (2010); “Bright water: hydrosols, water conservation and climate change”, Climatic Change (2011), Volume 105, Numbers 3-4, pages: 365-381; From the issue entitled "Climatic Change Letters”; Edited by Michael Oppenheimer; Pages 627-645; Received: 19 July 2009; Accepted: 28 September 2010; Available online under DOI: 10.1007/s10584-010-9965-8.
Fisheries management around the world has experimented with regulations to promote privatization, in order to reach such multifaceted goals as ending overfishing and reducing economic inefficiencies. This review surveys a wide range of empirical experiences in different contexts around the world to help provide a fuller picture of potential and sometimes disparate consequences from privatization in general and new ways of organizing around fishing that can follow in the wake of such measures. Looking at the many different participants in the fishing industry - from crew, small-boat owners, to households and communities - as well as the diverse socio-cultural contexts in which fishing takes place, enables a better understanding of who and what is impacted, how they are impacted, why and with what further consequences, such that communities come to be seen less oppositional to economy, but rather constituted by multiple scalar processes and by economic relations comprising different motivations and behaviors.
Keywords: Social impacts; Privatization; Fisheries.
Source: Julia Olson (2011); “Understanding and contextualizing social impacts from the privatization of fisheries: An overview”; Ocean & Coastal Management, Volume 54, Issue 5, May 2011, Pages 353-363; Available online: 19 February 2011, under DOI:10.1016/J.OCECOAMAN.2011.02.002.