Economics of additionality for environmental services from agriculture

We present a model of additionality for offsets sold from agriculture to industrial sector sources regulated by cap-and-trade. We consider a potential policy where agricultural sources would not be covered by cap-and-trade requirements but would be eligible to receive offsets whenever their emissions fall below a policy-specified baseline, and would not be penalized for emissions above their baseline. Major results are: (1) The optimal baseline should be set above the average counterfactual emissions of participating farms, an unexpected result that has been missing from the literature. (2) The optimal trading ratio should be greater than one (a ton of offsets counts for less than a ton of covered emissions) even under emissions certainty. Previous research has justified such trading ratios by emissions uncertainty. (3) Emissions uncertainty does not justify a change in the baseline if the accompanying emissions model is unbiased. (4) An optimal combination of policies is to subsidize offsets and tighten the baseline relative to the no-subsidy case.     

How safe is the playground? An environmental health risk assessment of As and Pb levels in school playing fields in NE England

The risk from potentially toxic elements in playground soils is of concern to children’s health as a result of the potential for intentional or unintentional consumption. Current approaches, based on total potentially toxic element concentration, may overestimate the risk. This has resulted in the development and use of in vitro gastrointestinal extraction protocols. The concentration of arsenic (As) and lead (Pb) in soils collected from 12 schools in north-east England has been compared with Soil Guideline Values from seven countries as well as reported literature concentrations for playgrounds and recreational parks. It was found that the mean As concentration of 14.1 ± 5.4 mg/kg does not exceed the England residential Soil Guideline Value in any location, while the mean Pb concentration of 298 ± 380 mg/kg is high but not excessive. Both concentrations have been assessed using the maximum potential daily intake from soil that a child could ingest. Based on this protocol Pb does not exceed the tolerable daily intake in any playground location, while As is generally 10 times lower than the oral index dose in the majority of playgrounds. The oral bioaccessibility of As and Pb was investigated. It was concluded that the highest concentrations were determined in the gastric phase with maximum bioaccessibilities of 54 and 46 % for As and Pb, respectively. Here we have demonstrated that minimal risk arises from the investigated playgrounds provided that good personal hygiene is adhered to.     

Temporal separation of two fin whale call types across the eastern North Pacific

Fin whales (Balaenoptera physalus) produce a variety of low-frequency, short-duration, frequency-modulated calls. The differences in temporal patterns between two fin whale call types are described from long-term passive acoustic data collected intermittently between 2005 and 2011 at three locations across the eastern North Pacific: the Bering Sea, off Southern California, and in Canal de Ballenas in the northern Gulf of California. Fin whale calls were detected at all sites year-round, during all periods with recordings. At all three locations, 40-Hz calls peaked in June, preceding a peak in 20-Hz calls by 3–5 months. Monitoring both call types may provide a more accurate insight into the seasonal presence of fin whales across the eastern North Pacific than can be obtained from a single call type. The 40-Hz call may be associated with a foraging function, and temporal separation between 40- and 20-Hz calls may indicate the separation between predominately feeding behavior and other social interactions.     

Seasonal and diel variation in movement rhythms of sand dollar, Peronella lesueuri (Valenciennes 1841), in Cockburn Sound, Western Australia

Rates and direction of movement in the sand dollar Peronella lesueuri were measured in summer and winter in Cockburn Sound, a large coastal embayment in south-western Australia. P. lesueuri was found to have a diurnal activity pattern throughout the year and had a greater movement rate in the summer (mean of 5.3 cm h^?1, day; 3.9 cm h^?1, night) than in the winter (mean of 2.7 cm h^?1, day; 2.0 cm h^?1, night). Seasonal change in temperature and physiological requirements by the sand dollar are the most likely reason for the seasonal differences. Reasons for diurnal variation were not clear. Direction of movement was found to be random at both times of the year. Based on these movement rates, one sand dollar can bioturbate an approximate area of 0.1 m² day^?1 and 36.4 m² year^?1. At a conservative density estimate of 0.5 sand dollars per m² it takes approximately 20 days for the sand dollars to rework the entire area of the sediments in the habitats they occupy.     

Body condition of predatory fishes linked to the availability of sandeels

Lesser sandeels Ammodytes marinus are eaten by a range of predatory fishes including commercially fished species, but are also exploited at large scale by industrial fisheries. Is availability of sandeels, as key prey source, linked to the body condition of predatory fishes? In the North Sea, the largest sandeel biomass is concentrated in the Dogger Bank region. Here we studied predator–sandeel interactions at two sites differing widely in sandeel abundance and local sandeel fishing effort. Surveys took place in 2004, 2005, and 2006, years when local sandeel densities observed at these sites were low, intermediate, and high, respectively. Five predator species––whiting, lesser weever, grey gurnard, plaice, and haddock––showed better body condition indices in either the years or study area (or both) characterised by higher local sandeel densities, when compared to sandeel-poorer conditions. Moreover, whiting, weever, and gurnard condition was better for those individuals actually observed to have eaten sandeels (based on stomach contents) than for those that had not. As body condition relates to growth, reproduction, and survival, predators in sandeel-rich conditions may be inferred to have a higher fitness. These links between sandeel availability, sandeel consumption, and predator condition hint that, if large-scale localised depletions of sandeels were to occur, negative indirect effects on predatory fish might become apparent, underlining the importance of considering the sandeel fishery in an ecosystem context.     

Comparison and Evaluation of Gridded Precipitation Datasets in a Kansas Agricultural Watershed Using SWAT

Gridded precipitation datasets are becoming a convenient substitute for gauge measurements in hydrological modeling; however, these data have not been fully evaluated across a range of conditions. We compared four gridded datasets (Daily Surface Weather and Climatological Summaries [DAYMET], North American Land Data Assimilation System [NLDAS], Global Land Data Assimilation System [GLDAS], and Parameter‐elevation Regressions on Independent Slopes Model [PRISM]) as precipitation data sources and evaluated how they affected hydrologic model performance when compared with a gauged dataset, Global Historical Climatology Network‐Daily (GHCN‐D). Analyses were performed for the Delaware Watershed at Perry Lake in eastern Kansas. Precipitation indices for DAYMET and PRISM precipitation closely matched GHCN‐D, whereas NLDAS and GLDAS showed weaker correlations. We also used these precipitation data as input to the Soil and Water Assessment Tool (SWAT) model that confirmed similar trends in streamflow simulation. For stations with complete data, GHCN‐D based SWAT‐simulated streamflow variability better than gridded precipitation data. During low flow periods we found PRISM performed better, whereas both DAYMET and NLDAS performed better in high flow years. Our results demonstrate that combining gridded precipitation sources with gauge‐based measurements can improve hydrologic model performance, especially for extreme events.     

Pollution,place, and premature death: evidence from a mid-sized city

ABSTRACT

Neighborhood life expectancy varies by as much as 10 years across the City of Louisville. In 2013, the Greater Louisville Project funded by local government, businesses, and foundations, argued these differences had little to do with environmental factors. The Greater Louisville Project (2013) study argued that these neighborhood differences could be attributed 40% to socio-economic factors (with a major emphasis on education), 10% to physical environment, 30% to health behaviors, and 20% to access to medical care. To test these claims, we construct our own model of neighborhood variation in years of potential life lost (YPLL) by adding two variables testing environmental degradation. We operationalise two separate measures of environmental contamination: proximity to EPA designated brownfield sites and proximity to chemical factories in an industrial park in the neighborhood known as “Rubbertown”. We conduct several regression analyses, which show a relationship between proximity to environmental contaminants and an increase in neighborhood YPLL. Our beta weights challenge the claims made by the Greater Louisville Project, which minimize the impact nearness to environmental contaminants has on reductions in life expectancy in Louisville neighborhoods.     

Investigations of ash fouling with cattle wastes as reburn fuel in a small-scale boiler burner under transient conditions

Fouling behavior under reburn conditions was investigated with cattle wastes (termed as feedlot biomass [FB]) and coal as reburn fuels under a transient condition and short-time operation. A small-scale (30 kW or 100,000 Btu/hr) boiler burner research facility was used for the reburn experiments. The fuels considered for these experiments were natural gas (NG) for the ashless case, pure coal, pure FB, and blends of coal and FB. Two parameters that were used to characterize the ash "fouling" were (1) the overall heat-transfer coefficient (OHTC) when burning NG and solid fuels as reburn fuels, and (2) the combustible loss through ash deposited on the surfaces of heat exchanger tubes and the bottom ash in the ash port. A new methodology is presented for determining ash-fouling behavior under transient conditions. Results on the OHTCs for solid reburn fuels are compared with the OHTCs for NG. It was found that the growth of the layer of ash depositions over longer periods typically lowers OHTC, and the increased concentration of ash in gas phase promotes radiation in high-temperature zones during initial periods while decreasing the heat transfer in low-temperature zones. The ash analyses indicated that the bottom ash in the ash port contained a smaller percentage of combustibles with a higher FB percentage in the fuels, indicating better performance compared with coal because small particles in FB burn faster and the FB has higher volatile matter on a dry ash-free basis promoting more burn out.     

Modulation of steroidogenesis by coastal waters and sewage effluents of Hong Kong, China, using the H295R assay

BACKGROUND, AIM, AND SCOPE: The presence of a variety of pollutants in the aquatic environment that can potentially interfere with the production of sex steroid hormones in wildlife and humans has been of increasing concern. The aim of the present study was to investigate the effects of extracts from Hong Kong marine waters, and influents and effluents from wastewater treatment plants on steroidogenesis using the H295R cell bioassay. After exposing H295R cells to extracts of water, the expression of four steroidogenic genes and the production of three steroid hormones were measured. MATERIALS AND METHODS: Water samples were collected during the summer of 2005 from 24 coastal marine areas and from the influents and effluents of two major waste water treatment plants (WWTPs) in Hong Kong, China. Samples were extracted by solid phase extraction (SPE). H295R cells were exposed for 48 h to dilutions of these extracts. Modulations of the expression of the steroidogenic genes CYP19, CYP17, 3betaHSD2, and CYP11beta2 were determined by measuring mRNA concentrations by real-time polymerase chain reaction (Q-RT-PCR). Production of the hormones progesterone (P), estradiol (E2), and testosterone (T) was quantified using enzyme linked immunosorbent assays (ELISA). RESULTS: Extracts from samples collected in two fish culture areas inhibited growth and proliferation of H295R cells at concentrations greater or equal to 10(5) L equivalents. The cells were exposed to the equivalent concentration of active substances in 10,000 L of water. Thus, to observe the same level of effect as observed in vitro on aquatic organisms would require a bioaccumulation factor of this same magnitude. None of the other 22 marine samples affected growth of the cells at any dilution tested. Twelve of the marine water samples completely inhibited the expression of CYP19 without affecting E2 production; inhibition of CYP17 expression was observed only in one of the samples while expression of CYP11beta2 was induced as much as five- and ninefold after exposure of cells to extracts from two locations. The expression of the progesterone gene 3betaHSD2 was not affected by any of the samples; only one sample induced approximately fourfold the production of E2. Although more than twofold inductions were observed for P and T production, none of these values were statistically significant to conclude effects on the production of these two hormones. While influents from WWTPs did not affect gene expression, an approximately 30% inhibition in the production of E2 and a 40% increase in P occurred for the exposure with influents from the Sha Tin and Stonecutters WWTPs, respectively. Effluents from WWTPs did not affect the production of any of the studied hormones, but a decrement in the expression of the aldosterone gene CYP11beta2 was observed for the Sha Tin WWTP exposure. No direct correlation could be established between gene expression and hormone production. DISCUSSION: Observed cytotoxicity in the two samples from fish culture areas suggest the presence of toxic compounds; chemical analysis is required for their full identification. Although effluents from WWTPs did not affect hormone production, other types of endocrine activity such as receptor-mediated effects cannot be ruled out. Interactions due to the complexity of the samples and alternative steroidogenic pathways might explain the lack of correlation between gene expression and hormone production results. CONCLUSIONS: Changes observed in gene expression and hormone production suggest the presence in Hong Kong coastal waters of pollutants with endocrine disruption potential and others of significant toxic effects. The aromatase and aldosterone genes seem to be the most affected by the exposures, while E2 and P are the hormones with more significant changes observed. Results also suggest effectiveness in the removing of compounds with endocrine activity by the WWTPs studied, as effluent samples did not significantly affect hormone production. The H295R cell showed to be a valuable toll in the battery required for the analysis of endocrine disrupting activities of complex environmental samples. RECOMMENDATIONS AND PERSPECTIVES: Due to the intrinsic complexity of environmental samples, a combination of analytical tools is required to realistically assess environmental conditions, especially in aquatic systems. In the evaluation of endocrine disrupting activities, the H295R cell bioassay should be used in combination with other genomic, biological, chemical, and hydrological tests to establish viable modes for endocrine disruption and identify compounds responsible for the observed effects.