‘Coastal squeeze’— an historical perspective

The use of salt marsh for agricultural use has probably been going on for thousands of years. This paper will look at the situation in southeast England, particularly the Wash. Here enclosure for extended grazing and over the last several hundred years, for arable cultivation, may have taken place since Roman Times. An enclosure of Freiston Shore salt marsh (1979) and a proposed further enclosure at Gedney Drove End at about the same time raised concerns about the cumulative effect of these developments on nature conservation interests. These concerns prompted the nature conservation agencies to oppose the Gedney Drove End enclosure. Though the conservation argument did not persuade the Government that no further enclosure should take place, economic circumstances changed such that the pressure for the creation of new agricultural land diminished. This marked the end of ‘reclamation’ in the Wash. Since then, in the UK at least, there have been no further enclosures of salt marsh for agriculture. What were the arguments that lead to this change? Up to this point the perceived wisdom, in the Wash at least, was that as enclosure took place new inter-tidal land was created to seaward— with no net loss of inter-tidal land. Today we accept that this is not the case and a policy of managed re-alignment has increasingly been adopted in England, at sites ranging from the Porlock shingle ridge in north Devon to the salt marshes of Freiston in the Wash. It is argued that recognition of ‘coastal squeeze’ probably began in the Wash some 20 years ago. It would appear that we are now witnessing a reversal of this trend. How far will it take us? Will we see a return of the large expanses of tidal swamp around the Wash and elsewhere along the southern North Sea coast? Is this an inevitable consequence of global warming? This paper provides an historical perspective of the issues and arguments that have led us to recognize ‘coastal squeeze’ and the importance of dynamic coast, including the European Commission’s ‘EURosion Project’, which reported in 2004 (Salman et al. 2004).     

FLOODPLAINS AND HOUSING VALUES: IMPLICATIONS FOR FLOOD MITIGATION PROJECTS1

ABSTRACT: The hedonic valuation method was used to quantify the impact of floodplain location on housing values in Fargo‐Moor‐head. Being located in the 100‐year floodplain lowered the home values by $8,990, and such homes were worth $10,241 less than similar homes located outside the floodplain before the major flood event of 1997. Required flood insurance premiums for these homes were determined to account for approximately 81 percent of this price depreciation. In contrast, homes in the 500‐year floodplain were worth $3,100 more than similar homes not in the floodplain. It was concluded that more disclosure is needed regarding the location of the 500‐year floodplain, and that the hedonic valuation method can be used to calculate the economic gains and losses associated with flood mitigation projects or floodplain remapping efforts that result in the reclassification of the legal floodplain status of individual homes.     

Results of Treatment Evaluations of a Contaminated Synthetic Soil

Under Phase I of EPA’s Superfund soil treatability research program, which was conducted from April to November 1987, a surrogate soil containing a wide range of chemical contaminants typically occurring at Superfund sites was prepared and subjected to bench- or pilot-scale performance evaluations using the following treatment technologies: 1) physical separation/volume reduction (soil washing); 2) chemical treatment (KPEG); 3) thermal desorption; 4 ) incineration; and 5) stabilization/fixation. This report covers the formulation and development of the surrogate soil; it also highlights the results of the five treatment evaluations. Virtually all of the analytical data underlying this research were developed using EPA-SW846 methods. Detailed project reports covering the findings of each study are available through EPA’s Risk Reduction Engineering Laboratory in Cincinnati, Ohio.     

From issues to indicators: developing robust community sustainability measures

Recent debate on sustainability indicator development has centred upon top-down and bottom-up methods. In practice, a key difficulty is the establishment of defensible issues and indicators to use. Here, we present a structured approach for transitioning from initial community consultation designed to elicit issues to the downstream definition, composition and measurement of those issues via indicators. The approach incorporates two quantitative techniques from the literature, analytic hierarchy process and Qualitative Sustainability System Index. The application of these techniques is designed to foster a better understanding of the priority of and relationships between issues, prior to the construction of measurement instruments and indicators of sustainability. We develop a prototype implementation of the approach, and elicit feedback from an expert panel on its suitability in a community sustainability context.     

Comparison of continuous and filter-based carbon measurements at the Fresno supersite

Results from six continuous and semicontinuous black carbon (BC) and elemental carbon (EC) measurement methods are compared for ambient samples collected from December 2003 through November 2004 at the Fresno Supersite in California. Instruments included a multi-angle absorption photometer (MAAP; lambda = 670 nm); a dual-wavelength (lambda = 370 and 880 nm) aethalometer; seven-color (lambda = 370, 470, 520, 590, 660, 880, and 950 nm) aethalometers; the Sunset Laboratory carbon aerosol analysis field instrument; a photoacoustic light absorption analyzer (lambda = 1047 nm); and the R&P 5400 ambient carbon particulate monitor. All of these acquired BC or EC measurements over periods of 1 min to 1 hr. Twenty-four-hour integrated filter samples were also acquired and analyzed by the Interagency Monitoring of Protected Visual Environments (IMPROVE) thermal/optical reflectance carbon analysis protocol. Site-specific mass absorption efficiencies estimated by comparing light absorption with IMPROVE EC concentrations were 5.5 m2/g for the MAAP, 10 m2/g for the aethalometer at a wavelength of 880 nm, and 2.3 m2/g for the photoacoustic analyzer; these differed from the default efficiencies of 6.5, 16.6, and 5 m2/g, respectively. Scaling absorption by inverse wavelength did not provide equivalent light absorption coefficients among the instruments for the Fresno aerosol measurements. Ratios of light absorption at 370 nm to those at 880 nm from the aethalometer were nearly twice as high in winter as in summer. This is consistent with wintertime contributions from vehicle exhaust and from residential wood combustion, which is believed to absorb more shorter-wavelength light. To reconcile BC and EC measurements obtained by different methods, a better understanding is needed of the wavelength dependence of light-absorption and mass-absorption efficiencies and how they vary with different aerosol composition.     

Chemical transformations of lead compounds under humid conditions: implications for bioaccessibility

This short communication documents chemical transformations caused by weathering of two Pb compounds that commonly occur in house dust. Chamber experiments were designed to simulate humid indoor environment conditions to determine whether Pb compounds undergo chemical transformations influencing bioaccessibility. Reference compounds of Pb metal (12 % bioaccessibility) and Pb sulfate (14 % bioaccessibility) were subjected to an oxygenated, humidified atmosphere in closed chambers for 4 months. X-ray diffraction (XRD) and X-ray absorption near-edge structure (XANES) spectroscopy were used to characterize the main Pb species, and the change in Pb bioaccessibility was determined using a simulated gastric acid digestion. At the end of the weathering period a small amount of Pb carbonate (9 % of total Pb) appeared in the Pb sulfate sample. Weathering of the Pb metal sample resulted in the formation of two compounds, hydrocerussite (Pb hydroxyl carbonate) and Pb oxide, in significant amounts (each accounted for 26 % of total Pb). The formation of highly bioaccessible Pb carbonate (73 % bioaccessibility), hydrocerussite (76 % bioaccessibility), and Pb oxide (67 % bioaccessibility) during weathering resulted in a measurable increase in the overall Pb bioaccessibility of both samples, which was significant (p = .002) in the case of the Pb metal sample. This study demonstrates that Pb compounds commonly found in indoor dust can ‘age’ into more bioaccessible forms under humid indoor conditions.     

The pattern of early growth trajectories affects adult breeding performance

Early environmental conditions can influence the pattern of growth and development. While poor conditions generally cause slower growth, normal adult size can still be reached if growth accelerates or is prolonged once conditions improve, but such catch-up growth may have deleterious effects later in life. Here we investigate for the first time how decelerating as well as accelerating growth trajectories, manipulated independently of food supply, affect subsequent breeding performance. In order to alter growth rates we subjected juvenile three-spined sticklebacks Gasterosteus aculeatus to a short period of altered environmental temperature (high, intermediate, or low), after which all fish had the same (intermediate) temperature regime. In addition, the perceived time stress (until the onset of the spawning season) was manipulated by conducting the experiment twice (in the winter and in the spring immediately prior to breeding) and by exposing half of the fish in each experiment to a delayed photoperiod (two months behind ambient). We found that fish showed full growth compensation, such that in all treatments they were of the same average size by the start of the breeding season. However, those compensating for low temperatures earlier in life (i.e., who then showed an accelerated growth trajectory) had reduced reproductive investment over the following two breeding seasons (males, reduced sexual ornaments and speed of building nests; females, reduced first clutch size, mean egg size, and eggs produced per year). Moreover, these deleterious effects were strongest when the perceived time available for growth compensation prior to breeding was shortest. In contrast, those fish with a decelerating growth trajectory as a result of exposure to high temperatures early in life showed an improved breeding performance compared to steadily growing controls. These results clearly demonstrate that both the shape of the growth trajectory (independent of food supply) and the time available for growth compensation have broad-reaching and prolonged effects on breeding performance, with ecological conditions that prompt catch-up growth just prior to the breeding season being especially damaging for both sexes.     

Costa Rica — Assessing Climate Mitigation Pathways to Support NDC Implementation

Environmental Modeling & Assessment - Costa Rica has set a very ambitious Nationally Determined Contribution (NDC). Despite the low-carbon footprint of its power sector, the goal set in its NDC...