A decision framework for estimating the cost of marine plastic pollution interventions

Marine plastic pollution has emerged as one of the most pressing environmental challenges of our time. Although there has been a surge in global investment for implementing interventions to mitigate plastic pollution, there has been little attention given to the cost of these interventions. We developed a decision support framework to identify the economic, social, and ecological costs and benefits of plastic pollution interventions for different sectors and stakeholders. We calculated net cost as a function of six cost and benefit categories with the following equation: cost of implementing an intervention (direct, indirect, and nonmonetary costs) minus recovered costs and benefits (monetary and nonmonetary) produced by the interventions. We applied our framework to two quantitative case studies (a solid waste management plan and a trash interceptor) and four comparative case studies, evaluating the costs of beach cleanups and waste-to-energy plants in various contexts, to identify factors that influence the costs of plastic pollution interventions. The socioeconomic context of implementation, the spatial scale of implementation, and the time scale of evaluation all influence costs and the distribution of costs across stakeholders. Our framework provides an approach to estimate and compare the costs of a range of interventions across sociopolitical and economic contexts.     

USING A CHOICE MODELLING APPROACH FOR CUSTOMER SERVICE STANDARDS IN URBAN WATER1

ABSTRACT: A series of reforms in the water industry in Australia has created a demand from the industry and regulators for objective methodologies to evaluate incremental changes in the customer service standards. In this paper, the use of choice modeling for estimating implicit prices associated with urban water supply attributes is explored. Results from multinomial logit (MNL) and random parameters logit (RPL) models show that increases in annual water bills and the frequency of future interruptions were the most important attributes. Implicit price confidence intervals based on the best models suggest that people are willing to pay positive amounts to achieve a water supply that is less frequently interrupted. The provision of alternative water supplies during an interruption and notification of the interruption were found to be unimportant to respondents. Choice modeling proved to be a useful technique and provided the industry and regulators with additional information for standard setting.     

Overgrowth competition in encrusting bryozoan assemblages of the intertidal and infralittoral zones of Alaska

Almost 2000 cheilostomatid–cheilostomatid (bryozoan) interactions were recorded from 110 rocks from intertidal and infralittoral zone locations at Kodiac Island in the Alaskan Boreal–Arctic. Intraspecific interactions were unusually rare; this may have resulted from inhibition of con-specific settlement by adult colonies. In one species, rank did vary as a function of depth. The proportion of determinate-species encounter-pairings (a pairing in which one competitor/species wins all encounters) and tied outcomes (whereby neither competitor/species wins or loses but are involved in a “standoff” or mutual overgrowth) increased from the upper midlittoral to the lower infralittoral. The assemblage of bryozoans formed a clear hierarchy, with a score of 0.83 on Tanaka and Nandakumar's transitivity index. Overgrowth dominants did not monopolise the assemblage. The most abundant species were mid- or lower-ranked competitors. The identity of the competitive species had a major influence on the outcome of encounters. Zooidal height and colony growth morphology were important factors determining overall overgrowth rank. The greatest number of interaction types was recorded on medium-sized (surface area >300 and <600 cm²) rocks, and the overall diversity of intertidal species was very high compared with studies conducted elsewhere. The high interaction and species diversity recorded may both have resulted from intermediate levels of disturbance. Received: 16 July 1998 / Accepted: 14 December 1999     

Perceptions of behaviors that cause and mitigate global warming and intentions to perform these behaviors

Individual household and travel behaviors represent a sizeable contribution to U.S. greenhouse gas emissions. This paper investigates people's knowledge of these behaviors and perceptions of these behaviors' impact in causing and mitigating climate change. In the present study, a sample of college students were asked to list the behaviors they perform that cause global warming (GW) and the behaviors they could perform to mitigate GW, to rate the impact of the behaviors in terms of their effect on causing or mitigating GW, and to rate their intention to perform each of the behaviors. Results revealed that this sample was well aware of the effect of driving on GW. However, participants underestimated the relative impact of adjusting the thermostat and eating meat on GW and overestimated the impact of littering on causing GW. Although knowledge about GW-mitigating behaviors was not consistently related to behavioral intention, belief that a behavior mitigated GW (whether accurate or not) was strongly related to intention to perform that behavior. Specifically, correlations between belief in the mitigating potential of a behavior and intention were relatively high for adjusting the thermostat, reducing meat consumption, and several behaviors that do not mitigate GW, but were relatively low for reducing driving and not littering. Practical implications and comparisons with previous literature are discussed.     

The Cl-initiated oxidation of CH3C(O)OCH=CH2, CH3C(O)OCH2CH=CH2, and CH2=CHC(O)O(CH2)3CH3 in the troposphere

Background, aim, and scope  

Unsaturated esters are emitted to the atmosphere from biogenic and anthropogenic sources, including those from the polymer industry. Little information exists concerning the atmospheric degradation of unsaturated esters, which are mainly initiated by OH radicals. Limited information is available on the degradation of alkenes by Cl atoms and almost no data exists for the reactions of unsaturated esters with Cl atoms. This data is necessary to assess the impact of such reactions in maritime environments where, under circumstances, OH radical- and Cl atom-initiated oxidation of the compounds can be important. Rate coefficients for the reactions of chlorine atoms with vinyl acetate, allyl acetate, and n-butyl acrylate have been determined at 298 ± 3 K and atmospheric pressure. The kinetic data have been used in combination with that for structurally similar compounds to infer the kinetic contributions from the possible reaction channels to the overall reaction rate.     

Growth trajectories of corallites and ages of polyps in massive colonies of reef-building corals of the genus Porites

Massive colonies of the reef-building coral genus Porites were collected at inshore, midshelf and shelf-edge reefs in the central section of the Great Barrier Reef in November 1987. These colonies were comprised of 4 species: P. lobata, P. lutea, P. solida and P. mayeri. X-radiographs made of skeletal slices cut from the skeletons displayed the annual density-banding pattern characteristic of massive corals, and appeared to show corallites within each slice. The average age of the 36 colonies was 41±12 yr (mean±SD). The images of corallites displayed by the X-radiographs were not images of actual corallites, but approximated the position and size of actual corallites. Consequently, X-radiographs provide information about the formation and growth trajectories of corallites, and about the history of the polyps which deposited the corallites. Individual corallites were always normal to the growth surface. The growth surface of the colonies became bumpy when they reached 50 to 80 mm in height and, as a result, corallites took on a fan-shaped arrangement within a bump. New corallites were initiated at the summit of each bump and grew upwards and outwards. Thus, growth of colonies resulted in corallites becoming increasingly displaced from the summit of a bump. The X-radiographs showed that corallite growth becomes occluded at the bottom of valleys between adjacent bumps. Corallite growth then stops and the associated polyps are probably resorbed. Annual density banding showed that the average age of polyps in these colonies was 2 to 3 yr, average life expectancy 5 yr, and that no polyp was likely to be older than 8 yr. Small but significant variations in polyp longevity between corals from different reefs were probably associated with significant differences in bumpiness of growth surfaces. Even in Porites colonies which have been growing for several centuries, polyp longevity is likely to be 5 yr.     

The Race for Space: Tracking Land-Cover Transformation in a Socio-ecological Landscape, South Africa

Biosphere Reserves attempt to align existing biodiversity conservation with sustainable resource use, specifically for improving socio-economic circumstances of resident communities. Typically, the Biosphere Reserve model is applied to an established landscape mosaic of existing land uses; these are often socio-ecological systems where strict environmental protection and community livelihoods are in conflict, and environmental degradation frequently accompanies “use”. This raises challenges for successful implementation of the model, as the reality of the existing land-use mosaic undermines the theoretical aspirations of the Biosphere concept. This study focuses on the Kruger to Canyons Biosphere Reserve (K2C), South Africa; a socio-ecological landscape where formal conservation is juxtaposed against extensive impoverished rural communities. We focus on land-cover changes of the existing land-use mosaic (1993–2006), specifically selected land-cover classes identified as important for biodiversity conservation and local-level resource utilization. We discuss the implications of transformation for conservation, sustainable resource-use, and K2C’s functioning as a “Biosphere Reserve”. Spatially, changes radiated outward from the settlement expanse, with little regard for the theoretical land-use zonation of the Biosphere Reserve. Settlement growth tracked transport routes, transforming cohesive areas of communal-use rangelands. Given the interdependencies between the settlement population and local environmental resources, the Impacted Vegetation class expanded accordingly, fragmenting the Intact Vegetation class, and merging rangelands. This has serious implications for sustainability of communal harvesting areas, and further transformation of intact habitat. The distribution and magnitude of Intact Vegetation losses raise concerns around connectivity and edge effects, with long-term consequences for ecological integrity of remnant habitat, and K2C’s existing network of protected areas.     

Coral calcification: Sources of error in radioisotope techniques

Isotopic exchange occurs between coral skeleton and ⁴⁵Ca⁺⁺ and H¹⁴CO ₃ ^- in seawater. Exchange of ¹⁴C onto skeletons is more rapid than exchange of ⁴⁵Ca⁺⁺. Exchange of ¹⁴C from skeletons to seawater takes place more slowly than exchange of ⁴⁵Ca⁺⁺ to seawater. When living coral is incubated in the dark with radioisotopes for 1 h, the tissues contain considerably more radioactivity than is associated with the skeleton. The tissue radioactivity reflects permeation of tissues and coelenteron by radioactive compounds from the incubation seawater. Addition of alkalis to cardioactive seawater results in a radioactive precipitate, part of which becomes associated with any coral skeleton present, and part of which forms on the wall of the containing vessel. Strong alkali removes biologically-deposited radioisotope from coral skeletons. Deposition, of ¹⁴C from H¹⁴CO ₃ ^- in skeletons of living coral incubated in the dark is greater than in dead coral. The reverse situation occurs with ⁴⁵Ca⁺⁺.     

Stock discrimination of orange roughy,Hoplostethus atlanticus,by parasite analysis

Seasonal changes of respiratory metabolism and biochemical composition were studied in Actinia equina L. (Cnidaria: Anthozoa) collected in 1982 and 1983 from two shore locations in Spain. Changes of metabolic activity follow closely those of biochemical constituents, particularly carbohydrates and lipids, showing maxima in late fall and spring. Weight dependence, established according to the exponential equation y=a x^b (x=weight), results in virtually isometric relationships for proteins, total lipids and sugars but not glycogen. Allometry for this last compound represents a reduction in glycogen level in connection with size decrease; this weight effect declines when glycogen levels rise, both in field and laboratory fed anemones, thus suggesting a stronger influence of food availability on storage in small anemones.