Impact of 100-Year Human Interventions on the Deltaic Coastal Zone of the Inner Thermaikos Gulf (Greece): A DPSIR Framework Analysis

The Axios River delta and the Inner Thermaikos Gulf coastal zone have experienced a long period of human interventions during the past 100 years. A post-evaluation of long run coastal zone changes under the Drivers-Pressures-State-Impacts-Response (DPSIR) conceptual framework is presented. The DPSIR approach is then used to project out into possible futures in order to connect with policy and management options proposed for the improvement of the current conditions and the achievement of sustainable development, in the coastal zone. Socio-economic driving forces with their origins in the end of the 19^th century have generated numerous pressures in the coastal environment that changed the state of the environment. In the first part of the last century, there was no coupling between change of state and policy. Due to increasing environmental awareness, a coupling became more apparent over the last thirty years. Human interventions include river route realignment, extensive drainage of the plains, irrigation network, roads and dam constructions. The consequences were positive for the economic development of the area, human health, and navigation for the port of Thessaloniki. In contrast, the manipulation and over-use of natural resources has led to a reduction of wetlands, biodiversity loss, stress on freshwater supplies, and subsidence of coastal areas, aquifer salinization, and rapid coastal erosion. Three plausible future scenarios are utilised in order to investigate the implications of this environmental change process and possible socio-economic consequences.     

Temporal and Spatial Turbidity Patterns Over 30 Years in a Managed Forest of Western Washington1

Abstract: Forest practices have progressively changed over the last 30 years in the Pacific Northwest to address water quality concerns. There have been some assessments of these new management practices made at a site scale but very few studies have attempted to evaluate their efficacy at reducing cumulative sediment production at a watershed scale. Such an evaluation is difficult due to the spatial and temporal variability in sediment delivery and transport processes. Due to this inherent variability, detecting a response to management changes requires a long‐term data record. We utilized a water quality dataset collected over 30 years at four locations in the Deschutes River watershed (western Washington) to assess trends in turbidity and whether sediment control procedures implemented over this time period had any detectable influence. The sample sites ranged from small headwater streams (2.4 and 3.0 km²) to the mainstem of the Deschutes River (150 km²). Declining trends in turbidity were detected at all the permanently monitored sites. The mainstem Deschutes River site, which integrates sediment processes from the entire study watershed, showed dramatic declines in turbidity even with continued active forest management. For the small basins, logging and road construction occurred in the 1970s and 1980s and turbidity declined thereafter, achieving prelogging levels by 2000. There are no temporal trends in flow that could be responsible for the observed trends in turbidity. Our results suggest that increased attention to reducing sediment production from roads and minimizing the amount of road runoff reaching stream channels has been the primary cause of the declining turbidity levels observed in this study.     

Processing of antifouling paint particles by Mytilus edulis

Particles of spent antifouling paint collected from a marine boatyard were ground and subsequently administered to the filter-feeding bivalve, Mytilus edulis, maintained in static aquaria. Concentrations of Cu and Zn were measured in seawater throughout a 16 h feeding phase and a 24 h depuration phase, in rejected and egested particles collected during the respective phases, and in the organisms themselves at the end of the experiments. Concentrations and distributions of Cu and Zn in processed particles indicated that M. edulis was able to ingest paint particles, regardless of whether nutritionally viable silt was present, and no mechanism of particle discrimination was evident. Enrichment of Cu and Zn in the visceral mass of individuals and in the aqueous phase during depuration supported these assertions, although elevated concentrations in other compartments of the organism (e.g. shell, gill) suggested that biotic and abiotic uptake of aqueous metal was also important.     

Estimating the contribution of point sources to atmospheric metals using single-particle mass spectrometry

Single-particle mass spectra were collected using an Aerosol Time-of-Flight Mass Spectrometer (ATOFMS) during December of 2003 and February of 2004 at an industrially impacted location in East St. Louis, IL. Hourly integrated peak areas for twenty ions were evaluated for their suitability in representing metals/metalloids, particularly those reported in the US EPA Toxic Release Inventory (TRI). Of the initial twenty ions examined, six (Al, As, Cu, Hg, Ti, and V) were found to be unsuitable due to strong isobaric interferences with commonly observed organic fragments, and one (Be) was found to have no significant signal. The usability of three ions (Co, Cr, and Mn) was limited due to suspected isobaric interferences based on temporal comparisons with commonly observed organic fragments. The identity of the remaining ions (Sb, Ba, Cd, Ca, Fe, Ni, Pb, K, Se, and Zn) was substantiated by comparing their signals with the integrated hourly signals of one or more isotope ions. When compared with one-in-six day integrated elemental data as determined by X-ray fluorescence spectroscopy (XRF), the daily integrated ATOFMS signal for several metal ions revealed a semi-quantitative relationship between ATOFMS peak area and XRF concentrations, although in some cases comparison of these measurements were poor at low elemental concentrations/ion signals due to isobaric interferences. A method of estimating the impact of local point sources was developed using hourly integrated ATOFMS peak areas, and this method attributed as much as 85% of the concentration of individual metals observed at the study site to local point sources. Hourly surface wind data were used in conjunction with TRI facility emissions data to reveal likely point sources impacting metal concentrations at the study site and to illustrate the utility of using single-particle mass spectral data to characterize atmospheric metals and identify point sources.     

Calculation of serum "total lipid" concentrations for the adjustment of persistent organohalogen toxicant measurements in human samples

Persistent organohalogen toxicants such as 2,3,7,8-tetrachlorodibenzo-p-dioxin or polychlorinated biphenyls measured in human serum are often expressed on a lipid weight basis, most commonly by dividing the toxicants' concentration by the weight of total lipids in the sample. Therefore, the manner in which this lipid adjustment is calculated may influence the final reported result. Gravimetric total lipid assays have been used, but they are time-consuming and sometimes may be ill-defined. Consequently, alternative methods using enzymatic assays have been developed based on summing the individual lipid species measured. Recent reports, however, have suggested that significantly different total lipid results may be obtained when using alternative formulae in a summation approach. In this report, we summarize the results obtained from lipid measurements of nearly 900 samples made as part of a study of a group of older American men (mean age 62 years), and we compare our total lipid estimates obtained by using both our standard and "short" formula (the latter based on total cholesterol and triglycerides only) with results obtained using the recently proposed alternative formulae. Our findings indicate that both our long and short formulae provide similar estimates of serum total lipid concentrations, and that differences observed in lipid estimates when using the newer alternative summation methods may reflect differences in how the term "total lipid" is defined, especially with regard to the need to include the contribution of the weight of the cholesterol ester fatty acids in the calculation.     

The potential future contribution of shipping to acidification of the Baltic Sea

International regulation of the emission of acidic sulphur and nitrogen oxides from commercial shipping has focused on the risks to human health, with little attention paid to the consequences for the marine environment. The introduction of stricter regulations in northern Europe has led to substantial investment in scrubbers that absorb the sulphur oxides in a counterflow of seawater. This paper examines the consequences of smokestack and scrubber release of acidic oxides in the Baltic Sea according to a range of scenarios for the coming decades. While shipping is projected to become a major source of strong acid deposition to the Baltic Sea by 2050, the long-term effect on the pH and alkalinity is projected to be significantly smaller than estimated from previous scoping studies. A significant contribution to this difference is the efficient export of surface water acidification to the North Sea on a timescale of 15–20 years.     

EFFECTWENESS OF INTEGRATED STORMWATER MANAGEMENT IN A PORTLAND,OREGON, WATERSHED1

ABSTRACT: The City of Portland's stormwater management program, winner of EPA's Environmental Excellence Award for 1996, is committed to partnership-based, cost-effective, “green” approaches to healthy neighborhoods and water quality. The stormwater program encourages innovative, non-structural pollution reduction techniques like native landscaping, stormwater pollution reduction bioswales and ponds, and public involvement and education. Effectiveness of stormwater best management practices (BMPs) has been difficult to determine on a citywide basis. Recognizing this problem, the City of Portland launched the Parkrose Pilot Project in 1994 to test the effectiveness of a wide range of BMPs in a small watershed in north Portland, the Parkrose catchment, and monitor the results prior to citywide implementation. This catchment was selected because of its small size (144 acres), its representative mix of land uses, and an extensive record of water quality monitoring data. This paper examines the City's strategy in selecting the Parkrose study area as a pilot watershed, the BMPs chosen for use in the watershed, and the results of the program to date. Final success of the Parkrose project will be gauged by the attainment of measurable pollution reduction within the catchment while providing opportunities for meaningful participation by the local community in achieving water quality. Involvement by private citizens in the community is crucial to the success of the project and to ensure compliance with the federal mandate to reduce pollutants to the maximum extent practicable.     

Surfactant-induced mobilisation of trace metals from estuarine sediment: implications for contaminant bioaccessibility and remediation

The mobilisation of metals (Al, Fe, Cd, Cu, Mn, Ni, Pb, Sn, Zn) from contaminated estuarine sediment has been examined using commercially available surfactants. Metal release by the anionic surfactant, sodium dodecyl sulphate (SDS), increased with increasing amphiphile concentration up to and above its critical micelle concentration (CMC). Metal mobilisation by the bile acid salt, sodium taurocholate, and the nonionic surfactant, Triton X-100, however, did not vary with amphiphile concentration. SDS was the most efficient surfactant in mobilising metals from the sample, and Cd, Cu and Ni were released to the greatest extents (12-18% of total metal at [SDS] > CMC). Metal mobilisation appeared to proceed via complexation with anionic amphiphiles and denudation of hydrophobic host phases. Surfactants may play an important role in the solubilisation of metals in the digestive environment of deposit-feeding animals and, potentially, in the remediation of metal-contaminated soil and sediment.     

Stakeholder perceptions of grassland ecosystem services in relation to knowledge on soil fertility and biodiversity

The concept of ecosystem services is increasingly being used by scientists and policy makers. However, most studies in this area have focussed on factors that regulate ecosystem functions (i.e. the potential to deliver ecosystem services) or the supply of ecosystem services. In contrast, demand for ecosystem services (i.e. the needs of beneficiaries) or understanding of the concept and the relative ranking of different ecosystem services by beneficiaries has received limited attention. The aim of this study was to identify in three European mountain regions the ecosystem services of grassland that different stakeholders identify (which ecosystem services for whom), the relative rankings of these ecosystem services, and how stakeholders perceive the provision of these ecosystem services to be related to agricultural activities. We found differences: (1) between farmers?? perceptions of ecosystem services across regions and (2) within regions, between knowledge of ecosystem services gained by regional experts through education and farmers?? local field-based knowledge. Nevertheless, we identified a common set of ecosystem services that were considered important by stakeholders across the three regions, including soil stability, water quantity and quality, forage quality, conservation of botanical diversity, aesthetics and recreation (for regional experts), and forage quantity and aesthetic (for local farmers). We observed two contrasting stakeholder representations of the effects of agricultural management on ecosystem services delivery, one negative and the other positive (considering low to medium management intensity). These representations were determined by stakeholders?? perceptions of the relationships between soil fertility and biodiversity. Overall, differences in perceptions highlighted in this study show that practitioners, policy makers and researchers should be more explicit in their uses of the ecosystem services concept in order to be correctly understood and to foster improved communication among stakeholders.     

Impacts of boat paint chips on the distribution and availability of copper in an English ria

Discarded paint chips collected from a leisure boat maintenance facility on the Kingsbridge estuary, SW England, have been fractionated to <63 microm and chemically characterised. At about 16% by weight, Cu was the most abundant metallic component, reflecting its biocidal application in antifouling paint. Bioavailability of Cu in the chips, determined by protein digestion, was about 4%, and sea water leachability was about 8%. Copper concentrations in fractionated intertidal sediment from the estuary were highly variable (<10-460 microg g(-1)). Specifically, greatest concentrations and greatest variability among replicates were found in samples collected near boat maintenance facilities. Bioavailability of Cu in sediment averaged 7% but was also variable. We attribute Cu "hot spots" to heterogeneous contamination of local sediment by small quantities of paint chips. Contamination may arise directly, from relatively inert particulates, or indirectly, via release of Cu from chips to interstitial waters and its subsequent adsorption to local sediment.