Remediation and stewardship: Coexisting processes to protect health and the environment

Organizations that manage property that poses risks for surrounding communities need to practice stewardship. Stewardship is defined as carrying out the responsibility to manage land and facilities in a sustainable manner, while being accountable to others who have a stake in those resources. This article reviews six case studies of organizational stewardship and derives a set of five lessons learned, along with four challenges. Lessons include developing stewardship goals, good stakeholder relationships, multiple approaches to safety, and encouraging innovation and stable funding. Challenges include bureaucratic processes, burdensome regulations, organizational continuity, and inter‐organizational cooperation. These crosscutting lessons learned about how to achieve success or avoid failure in long‐term management of resources can be applied to all types of public and private agencies, including the long‐term management of environmental contamination. © 2003 Wiley Periodicals, Inc.     

Trophic ecology and the related functional morphology of the deepwater medusa <Emphasis Type="Italic">Periphylla periphylla</Emphasis> (Scyphozoa,Coronata)

Remotely operated vehicle (ROV)-based field studies on the distribution and behaviour of Periphylla periphylla Péron and Lesueur (Ann Mus Hist Nat Marseille 14:316–366, 1809), from three Norwegian fjords have been combined with on-board experiments and morphological and histological studies in order to understand the trophic ecology of this species. Field studies from one of the fjords showed that the zooplankton biomass was negatively related with P. periphylla abundance, indicating a predatory effect. The majority of zooplankton biomass tended to be distributed above the aggregation of P. periphylla, which in turn showed highest abundance at 100–200 m depth. Observation on the orientation of medusae passing the ROV when descending down in the water column at dawn and dusk, showed no consistency with the theory of diel vertical migration. Estimated metabolic demand of P. periphylla indicated a daily predation impact on the prey assemblage of 13% as an average for the fjord. In situ behavioural observations showed that the dominant tentacle posture of large medusae was straight upward, with tentacles extended to the oral–aboral body axis. The hunting mode alternates between ambush and ramming, whereby tentacle posture minimises the water turbulence that may otherwise alarm the prey. The musculature of the tentacles is well developed, with an especially strong longitudinal muscle on the oral side, facilitating fast movement of the tentacle towards the mouth. In addition, ring-, radial-, and diagonal musculatures are also present. The diagonal is probably most important for the corkscrew retraction of the tentacle, used at the moment of prey capture. Results from laboratory experiments show that different body-parts of P. periphylla vary in sensitivity for chemical and mechanical stimuli, including hydrodynamic disturbance and vibration in the surrounding water. Feeding success is facilitated by combining the vibration-sense on the tentacle tips and the marginal lappets, the touch-sense on the tentacle bases and marginal lappets, and a taste control of the captured prey at the mouthlips.     

Metabolism and model of an estuarine bay ecosystem affected by a coastal power plant

The effects of a coastal power plant on an outer estuarine bay ecosystem on the west coast of Florida were evaluated with measurements and an ecological model. Field measurements of community metabolism and biomass were taken from the thermally affected bay and from similar control bays. Model simulations were used to help understand these observations in terms of ecosystem structure and functioning.In the outer discharge bay the direct impact of the thermal plume was diluted and spread overlarge areas. The ecosystem developed structure and functions with lower biomass than in the control bays but with slightly faster rates of organic turnover. The productive turnover time of producer biomass during the summer was about 5 days in the discharge bay and about 6 days in the control bays. Power plant influence on total community metabolism was small with less than 10% difference in annual averages between the discharge and control bays (5.22 and 5.58 g O₂/m²/day). The selection for faster metabolic turnover rates in the discharge by was evidenced by a dominance of plankton metabolism over benthic metabolism. The annual average gross planktonic production was around 3 g O₂/m²/day in the discharge bay and around 2 g/m²/day in the control bays.In the model, temperature served as a stimulant to both productivity and respiration. When the isolated effects of increased temperature were simulated the model responded with lower producer biomass and faster rates of organic turnover, as was found in field measurements. These simulations also showed increased nutrient recycling and indicated patterns of temperature-induced migrations. Since power plant operation affected water exchange in the bays, several levels of total water exchange were simulated. These simulations indicated the importance of water exchange as a stabilizing factor, especially for sensitive compartments with rapid turnover rates (i.e. plankton and phosphorus stocks). Simulations of the effects of future power plant units on the bay ecosystem showed no large changes in total metabolism but indicated larger effects of plankton entrainment mortality and temperature-induced migrations of larger organisms.     

Set-Back Distances to Protect Nesting Bird Colonies from Human Disturbance in Florida

Breeding colonial waterbirds are particularly susceptible to human disturbance because of their high-density nesting habits. Identified detriments to reproductive success include egg and nestling mortality, nest evacuation, reduced nestling body mass and slower growth, premature fledging, and modified adult behaviors. Fifteen species of colonial waterbirds nesting at 17 colonies in north and central Florida were exposed to three different human disturbance mechanisms (HDMs) in order to determine recommended set-back (RS) distances for protecting these mixed-species nesting assemblages. Both intraspecific and interspecific variation were observed in flushing response distances to the same human disturbance mechanisms. In general, colonial waterbirds exhibited greater average flush distances in reaction to a walking approach than to approaching motor boats. Recommended set-back distances were estimated using a formula based on the mean plus 1.6495 standard deviations of the observed flushing distances plus 40 meters [X = exp (X + 1.6495X + 40)]. In general, a recommended set-back distance of about 100 meters for wading bird colonies and 180 meters for mixed tern/skimmer colonies should be adequate to effectively buffer the sites we studies from human disturbance caused by approach of pedestrians and motor boats. We recommend follow-up studies to test our model at other breeding colonies.     

Source of lead in humans from Broken Hill mining community

This paper documents the first precise lead isotope measurements for men, women and children from the same family in an attempt to determine the source of lead in their blood. The subjects reside in one of the world's largest lead mining cities, Broken Hill, NSW, Australia. Biological and environmental samples have been compared using isotopic compositions and lead contents. Adult males have isotopic profiles (or compositions) which appear to be related to their occupations. Adult females have low blood leads (<10 g dL^–1) and their main source of lead is not from the mine dumps around which the city is built but probably from a mixture of petrol, food and perhaps water. The blood lead contents in children from 1 to 14 years old vary and are partly dependent on age. There is a moderate correlation of blood lead and isotopic compositions (r = 0.73) indicating that a significant component of blood lead derives from the mine dumps in children with elevated blood leads. Some children with blood leads <20 g dL^–1, however, also have a dominant component of mine lead in their blood     

An exploratory look at hydrocarbon data from the Photochemical Assessment Monitoring Stations network

This paper describes some characteristics of speciated nonmethane organic compound (NMOC) data collected in 1994 at five Photochemical Assessment Monitoring Stations (PAMS) and archived in the U.S. Environmental Protection Agency's Aerometric Information Retrieval System (AIRS). Topics include data completeness, distribution of individual NMOCs in concentration categories relative to minimum detectable levels, percentage of total NMOC associated with the sum of the 55 PAMS target compounds, and use of scatterplots to diagnose chromatographic misidentification of compounds. This is an early examination of a database that is expanding rapidly, and the insights presented here may be useful to both the producers and future users of the data for establishing consistency and quality control.     

Assuring the quality of data in the pesticide residue laboratory

Abstract

The importance of quality control procedures to the collection of pesticide residue data is discussed. The equipment requirements of an adequate, safe pesticide residue laboratory are presented. Equipment maintenance, personnel training, and preservation of samples is also reviewed. Appropriate objectives for an intra‐laboratory quality control program are outlined.     

Sequential climate decisions under uncertainty: An integrated framework

We develop an integrated framework for evaluating sequential greenhouse gas abatement policies under uncertainty. The analysis integrates information concerning the magnitude, timing, and impacts of climate change with data on the likely effectiveness and cost of possible response options. Reduced-scale representations of the global climate system, drawn from the MIT Integrated Global System Model, form the empirical basis of the analysis. The method is illustrated in application to emissions control policies of the form considered under the United Nations Framework Convention on Climate Change.