Application of the DPSIR framework to environmental degradation assessment in northern Ghana

In many communities in northern Ghana, the environment has been altered by complex natural and human driven forces with significant impact on the lives of their inhabitants. The need to formulate an improved, holistic and consistent methodological approach to assess the problem is critical for sustainable natural resource management. This paper examines the potential of the DPSIR environmental assessment framework utilizing GIS‐based participatory methodology in the assessment of environmental degradation in northern Ghana. Community truthing tools such as key informant interviews, focus group discussions, participant observation and participatory Geographical Information Systems (GIS) were employed as a means of soliciting societal responses integrated to conventional GIS spatial analysis to measure the indicators of the Driving force–Pressure–State–Impacts–Response (DPSIR) assessment framework. Post classification GIS imagery results show a marked natural vegetation decrease of 634 km2 (42%) of the study area with a corresponding increase of 600 km² (39%) of grasses and built‐up and barren environment in the period of 14 years from 1990 to 2004. This is attributed to extreme climatic conditions and human driven causes such as poverty, population growth, migration and land tenure system. Poverty reduction strategies, amendment of the Mining and Mineral Law (PNDC law 153), improvement of the existing land tenure system and the control of migrants and Fulani herdsmen from neighbouring Burkina Faso were some of the solutions selected by the research participants, to be emphasized in the National Environmental Action Plan (EPA Act 490). This paper concludes that the DPSIR environmental assessment framework is an effective means of organizing complex environmental information to facilitate policy decision making.     

Seasonal variations in activity concentrations of 99Tc and 137Cs in the edible meat fraction of crabs and lobsters from the central Irish Sea

Discharges of most radionuclides into the Irish Sea from the BNFL site at Sellafield have decreased over the past 20 years or so. For a few radionuclides, however, discharges have peaked more recently. Notably, operation of the Enhanced Actinide Removal Plant (EARP) since 1994 has led to an increase in discharges of (99)Tc, as a result of the treatment of previously stored waste, with consequent increases in (99)Tc activity concentrations in a number of marine species, particularly in crustaceans such as lobsters. Previous research has considered the significance of factors such as sex and body weight on radionuclide concentrations. The current project set out to investigate whether seasonal variations in radionuclide concentrations in crabs and lobsters occur, with particular emphasis on the dynamics of (99)Tc and (137)Cs. Organisms were obtained from a site off the Isle of Man, where radionuclide concentrations were measurable but the site was sufficiently distant from Sellafield that the radionuclides were well mixed in the water column and not likely to be influenced by the pulsed nature of discharges of (99)Tc. Crab and lobster samples were collected monthly, between February 2000 and February 2001. Fifteen or 16 individuals (evenly split as male and female) of each species were collected on each occasion. Seawater samples were also collected over the 12-month period. Activity concentrations of (99)Tc in the edible meat fraction (both brown and white meat) ranged from 0.23 to 2.46 Bq kg(-1) (fresh weight (fw)) in crabs and 124 to 216 Bq kg(-1) (fw) in lobsters, with no observed seasonal variations. Activity concentrations of (137)Cs in both crab and lobster were lower, ranging from <0.16 to 0.85 Bq kg(-1) for crab meat (fw) and <0.3 to 3.3 Bq kg(-1) for lobster meat (fw). A statistically significant increase in activity concentrations of (137)Cs in the meat was observed in the summer months for both crab and lobster. The cause has not been investigated but may be related to the laying down of energy reserves during the active feeding period over the summer. At all times, uptake of (99)Tc is higher in the brown meat fraction of both crabs and lobsters, whilst (137)Cs is more uniformly distributed. These results are used to discuss the implications for sampling and monitoring programmes.     

Climate change and the geography of weed damage: Analysis of U.S. maize systems suggests the potential for significant range transformations

By the end of the century, climate change projections under a “business-as-usual” emissions scenario suggest a globally averaged warming of 2.4–6.4 °C. If these forecasts are realized, cropping systems are likely to experience significant geographic range transformations among damaging endemic weed species and new vulnerabilities to exotic weed invasions. To anticipate these changes and to devise management strategies for proactively addressing them, it is necessary to characterize the environmental conditions that make specific weed species abundant, competitive, and therefore damaging the production of particular crops (i.e. defining the damage niche). In this study, U.S. maize is used as a model system to explore the implications of climate change on the distribution of damaging agricultural weeds. To accomplish this, we couple ensemble climate change projections of annual temperature and precipitation with survey data of troublesome weed species in maize. At the state scale, space-for-time substitution techniques are used to suggest the potential magnitude of change among damaging weed communities. To explore how the geography of damage for specific species may evolve over the next century, bioclimatic range rules were derived for two weed species that are pervasive in the Northern (Abutilon theophrasti Medicus, ABUTH) and Southern (Sorghum halepense (L.) Pers., SORHA) U.S. Results from both analyses suggest that the composition of damaging weed communities may be fundamentally altered by climate change. In some states, potential changes in the coming decades are commensurate to those possible by the end of the century. Regions such as the Northeastern U.S. may prove particularly vulnerable with emerging climate conditions favoring few weed species of present-day significance. In contrast, regions like the mid-South are likely to experience fewer shifts even with a similar magnitude in climate change. By the end of the century in the U.S. Corn Belt, cold-tolerant species like A. theophrasti may be of minor importance whereas S. halepense, a predominantly Southern U.S. weed species at present, may become common and damaging to maize production with its damage niche advancing 200–600 km north of its present-day distribution.     

Uptake and depuration of 131I from labelled diatoms (Skeletonema costatum) to the edible periwinkle (Littorina littorea)

Uptake and depuration of (131)I into winkles through consumption of the diatom Skeletonema costatum is described. The work follows on from previous studies that investigated the uptake of iodine into winkles from seawater and seaweed. Incorporation of (131)I in S. costatum from labelled seawater followed linear first-order kinetics with an uptake half-time of 0.40 days. Iodine uptake in winkles from labelled S. costatum also followed linear first-order kinetics, with a calculated equilibrium concentration (C(infinity)) of 42Bqkg(-1) and a transfer factor (TF) of 1.1x10(-4) with respect to labelled diatom food. This TF is lower than that observed for uptake of (131)I in winkles from labelled seaweed. For the depuration stage, a biphasic sequence with biological half-lives of 1.3 and 255 days was determined. The first phase is biokinetically important, given that winkles can lose two-thirds of their activity during that period. This study shows that, whilst winkles can obtain radioactive iodine from phytoplankton consumption, they do not retain the majority of that activity for very long. Hence, compared with other exposure pathways, such as uptake from seawater and macroalgae, incorporation from phytoplankton is a relatively minor exposure route.     

Policy design,spatial planning and climate change adaptation: a case study from Australia

There are gaps in the existing climate change adaptation literature concerning the design of spatial planning instruments and the relationship between policy instruments and the sociopolitical barriers to adaptation reform. To help address this gap, this article presents a typology of spatial planning instruments for adaptation and analyses the pattern of instrument choice in Australian planning processes in order to shed light on contextual factors that can impede adaptation. The analysis highlights how policy design can amplify the barriers to adaptation by arranging policy actors in ways inimical to reform and stripping decision makers of the instruments necessary to make and sustain desired policy changes.     

Total mercury in marine species from the French coast of the Eastern English Channel

Mercury (Hg) in fish can present a potential risk to wildlife and human consumers. Mercury levels were determined in 12 fish species and 2 invertebrate species from the French coast of the Eastern English Channel collected in June and November 2012. Total mercury concentrations in the muscle tissues ranged between 0.04 and 1.63 µg g^-1 (d.w.). Dab and sandeel displayed a significant positive correlation between Hg concentrations and fish length. Seasonal differences in Hg concentrations were observed for dab and shrimp. The lesser weever showed significantly higher concentrations of Hg (0.97 ± 0.34 µg g^-1 d. w.) than all other species. Gobies and sprat, which had the smallest size, showed significantly lower concentrations than herring, whiting, pout and sardine. Among the considered species, flatfish such as dab, flounder, plaice and sole displayed intermediate levels of Hg. In the present study, the fish age expressed as specimen length seems to be one of the major factors governing Hg contents in muscle tissues. Finally, mercury concentrations in commercial fish from the Eastern English Channel were below the levels fixed by the European Union for total mercury in edible parts of fish products.     

Escherichia coli loading at or near base flow in a mixed-use watershed

This study analyzed the occurrence of Escherichia coli in a mixed land-use watershed with human, cattle, and wildlife fecal inputs located in a karstic geologic region using synoptic monitoring (samples taken throughout the watershed system) during base-flow conditions. The objective of the study was to evaluate the occurrence of E. coli during base-flow conditions for several months at seven different main channel and nine different tributary sampling sites in the Stock Creek watershed, a 49.3-km(2) basin located in Knoxville, TN. Escherichia coli densities were measured using the Colilert (Defined Substrate Technology) method. The instantaneous loads for E. coli were determined from measured flow rates and E. coli densities, with the highest loading rates observed in the late fall. The study indicated a strong correlation between E. coli load rate (colony-forming units [CFU]/d), 7-d antecedent precipitation, and turbidity. Water quality data, however, also exhibited a spatial dependency; for example, the E. coli load rate was better correlated with turbidity in the slower draining basin tailwater sampling sites than in the faster draining upstream headwater sampling sites. In the headwater sites, the E. coli load rate was better correlated with 7-d antecedent precipitation than turbidity.     

Identifying sources of fecal contamination inexpensively with targeted sampling and bacterial source tracking

Most bacterial source tracking (BST) methods are too expensive for most communities to afford. We developed targeted sampling as a prelude to BST to reduce these costs. We combined targeted sampling with three inexpensive BST methods, Enterococcus speciation, detection of the esp gene, and fluorometry, to confirm the sources of fecal contamination to beaches on Georgia's Jekyll and Sea Islands during calm and stormy weather conditions. For Jekyll Island, the most likely source of contamination was bird feces because the percentage of Ent. faecalis was high (30%) and the esp gene was not detected. For the Sea Island beach during calm conditions, the most likely sources of fecal contamination were leaking sewer lines and wildlife feces. The leaking sewer lines were confirmed with fluorometry and detection of the esp gene. For the Sea Island beach during stormflow conditions, the most likely sources of fecal contamination were wildlife feces and runoff discharging from two county-maintained pipes. For the pipes, the most likely source of contamination was bird feces because the percentage of Ent. faecalis was high (30%) and the esp gene was not detected. Sediments were also a reservoir of fecal enterococci for both Jekyll and Sea Islands. Combining targeted sampling with two or more BST methods identified sources of fecal contamination quickly, easily, and inexpensively. This combination was the first time targeted sampling was conducted during stormy conditions, and the first time targeted sampling was combined with enterococcal speciation, detection of the esp gene, and fluorometry.     

Like father,like son? Intergenerational transmission of values,attitudes, and behaviours in the environmental domain

How is young people's pro-environmental orientation related to their parents' pro-environmental values, attitudes, and behaviours? To answer this question, we examine parent–child similarities of general values as well as specific attitudes and behaviours related to three common household practices: purchasing environmentally friendly products, curtailing electricity use, and handling waste responsibly in a sample of 601 Danish families. Significant and positive, but weak correlations between parents' and children's values are found across all of Schwartz's ten value domains. The parent–child correlations are stronger for specific pro-environmental attitudes and behaviours. The positive correlations suggest that family socialization exert a significant influence on young consumers' pro-environmental orientation. Still, the young generation is, on average, significantly less environmentally concerned than their parents' generation. Implications of these findings are discussed.