Postcopulatory sexual selection favours intrinsically good sperm competitors

We used guppies to study repeatability in sperm competitiveness and postcopulatory sexual selection on male ornamentation. In a block design involving 25 pairs of males, artificial insemination was used to mate each pair (A and B) to four unrelated females—two that were mated with the combined ejaculates of both males (sperm-competition treatment) and two receiving sperm from each of the two males individually (single-male treatment). Our analysis revealed significantly repeatable patterns of paternity across females in the sperm-competition treatment, suggesting that certain males are intrinsically better sperm competitors than others, irrespective of female identity. Next, we compared mean brood success (number of offspring per brood) between sperm competition and single-male treatments. We found no significant effect of treatment on female fecundity, suggesting that the previously reported direct benefits of polyandry in this species may be due to factors such as differential maternal effects or differences in the number of inseminated sperm between treatments. Our artificial insemination assay was designed to control both factors. Finally, we determined whether variation in relative paternity was random with respect to male phenotype. Unlike previous work on Trinidadian populations, we found no significant relationship between male sexual ornamentation and sperm competitiveness in the focal population.     

Regulation with direct benefits of information disclosure and imperfect monitoring

We model the optimal design of programs requiring heterogeneous firms to disclose harmful emissions when disclosure yields both direct and indirect benefits. The indirect benefit arises from the internalization of social costs and resulting reduction in emissions. The direct benefit results from the disclosure of previously private information which is valuable to potentially harmed parties. Previous theoretical and empirical analyses of such programs restrict attention to the former benefit while the stated motivation for such programs highlights the latter benefit. When disclosure yields both direct and indirect benefits, policymakers face a tradeoff between inducing truthful self-reporting and deterring emissions. Internalizing the social costs of emissions, such as through an emissions tax, will deter emissions, but may also reduce incentives for firms to truthfully report their emissions.     

THE EFFECTS OF CLIMATE CHANGE ON STREAM FLOW AND NUTRIENT LOADING'

ABSTRACT: This study assesses the potential impact of climate change on stream flow and nutrient loading in six watersheds of the Susquehanna River Basin using the Generalized Watershed Loading Function (GWLF). The model was used to simulate changes in stream flow and nutrient loads under a transient climate change scenario for each watershed. Under an assumption of no change in land cover and land management, the model was used to predict monthly changes in stream flow and nutrient loads for future climate conditions. Mean annual stream flow and nutrient loads increased for most watersheds, but decreased in one watershed that was intensively cultivated. Nutrient loading slightly decreased in April and late summer for several watersheds as a result of early snowmelt and increasing evapotranspiration. Spatial and temporal variability of stream flow and nutrient loads under the transient climate scenario indicates that different approaches for future water resource management may be useful.     

Assessing the demand of solid waste disposal in urban region by urban dynamics modelling in a GIS environment

The twentieth century saw a dramatic increase in the production of urban solid waste, reflecting unprecedented global levels of economic activity. Despite some efforts to reduce and recover the waste, disposal in landfills is still the most usual destination. However, landfill has become more difficult to implement because of its increasing cost, community opposition to landfill siting, and more restrictive environmental regulations regarding the siting and operation of landfills. Moreover, disposal in landfill is the waste destination method with the largest demand for land, while land is a resource whose availability has been decreasing in urban systems. Shortage of land for landfills is a problem frequently cited in the literature as a physical constraint. Nonetheless, the shortage of land for waste disposal has not been fully studied and, in particular, quantified. This paper presents a method to quantify the relationship between the demand and supply of suitable land for waste disposal over time using a geographic information system and modelling techniques. Based on projections of population growth, urban sprawl and waste generation the method can allow policy and decision-makers to measure the dimension of the problem of shortage of land into the future. The procedure can provide information to guide the design and schedule of programs to reduce and recover waste, and can potentially lead to a better use of the land resource. Porto Alegre City, Brazil was used as the case study to illustrate and analyse the approach. By testing different waste management scenarios, the results indicated that the demand for land for waste disposal overcomes the supply of suitable land for this use in the study area before the year 2050.     

Natural and Anthropogenic Changes in The Chemistry of Six UK Mountain Lakes, 1988 to 2000

Trends have been analysed for 12 years ofchemical data from six mountain lakes in the UK AcidWaters Monitoring Network (AWMN). With minimal localanthropogenic impacts, these sites offer the bestavailable opportunity for clear identification of surfacewater chemical response to external factors, whethernatural or anthropogenic. Results indicate that naturalclimatic variations have had a major impact on lakechemistry, through fluctuations in (i) intensity ofstorms, which cause dilution of weathering-derived basecations, and/or displacement of hydrogen and aluminiumions on soil exchange sites by deposited marine basecations; and (ii) winter temperature, which is thought tobe inversely related to spring nitrate (NO₃) maxima.Both climatic factors can be linked to the North AtlanticOscillation. For the first decade of AWMN monitoringthese natural `confounding factors' to a significantextent obscured any recovery from acidification due todeclining anthropogenic sulphur deposition. However, theadditional data presented here provide strengtheningevidence for chemical recovery at a number of sites, atwhich decreases in sulphate (SO₄), acidity andlabile aluminium can now be identified. It is believedthat changes at these sensitive mountain lake sites mayherald more widespread recovery in UK surface waters aspollutant emissions decline further. However, largeincreases in dissolved organic carbon, and hence inorganic acidity, may have partially offset reductions inmineral acidity. The cause of these increases remainsuncertain, but may be linked to climatic change.     

Northern Rivers Ecosystem Initiative: Distribution and Effects of Contaminants

In response to a number of recommendations following the Northern Rivers Basin Studies (NRBS) contaminant program, the Northern Rivers Ecosystem Initiative (NREI) focused considerable attention on assessing contaminants from specific sources including pulp mill effluents, atmospheric transport of mercury and the Alberta oil sands operations. NRBS identified a number of major contaminants of concern including polychlorinated biphenyls, dioxins and furans, mercury and various hydrocarbons. Together, the NRBS and the NREI studies have demonstrated major declines in the levels of dioxins and furans over the last decade as pulp and paper mills have changed their process and treatment strategies in response to new Federal regulations. Polychlorinated biphenyls however, continue to be a concern for the region as their levels have not declined in fish and sediments over the course of these studies. Higher levels in sediments downstream of Grande Prairie and Hinton were identified, but the source of these contaminants remains unknown. Chlorinated pesticides were also investigated, and although toxaphene, DDT and other chlorinated organic pesticides were detected in fish tissue, they were present at very low levels. Studies on the oil sands industry in northern Alberta demonstrated limited impacts on the Athabasca River to date, although studies did identify slight to moderate impacts of natural oil seeps on fish and benthic communities in tributary streams. NREI studies also identified endocrine active compounds in the three pulp and paper mill effluents tested, but endocrine disruptive effects in wild fish were minimal. Municipal sewage effluents also contain endocrine active compounds and it is recommended that monitoring continue around these point sources.     

Contrasting controls on arsenic and lead budgets for a degraded peatland catchment in Northern England

Atmospheric deposition of trace metals and metalloids from anthropogenic sources has led to the contamination of many European peatlands. To assess the fate and behaviour of previously deposited arsenic and lead, we constructed catchment-scale mass budgets for a degraded peatland in Northern England. Our results show a large net export of both lead and arsenic via runoff (282 ± 21.3 gPb ha(-1) y(-1) and 60.4 ± 10.5 gAs ha(-1) y(-1)), but contrasting controls on this release. Suspended particulates account for the majority of lead export, whereas the aqueous phase dominates arsenic export. Lead release is driven by geomorphological processes and is a primary effect of erosion. Arsenic release is driven by the formation of a redox-dynamic zone in the peat associated with water table drawdown, a secondary effect of gully erosion. Degradation of peatland environments by natural and anthropogenic processes has the potential to release the accumulated pool of legacy contaminants to surface waters.     

Applying sustainable development principles to contaminated land management using the SuRF‐UK framework

In the past decade, management of historically contaminated land has largely been based on prevention of unacceptable risks to human health and the environment, to ensure a site is “fit for use.” More recently, interest has been shown in including sustainability as a decision‐making criterion. Sustainability concerns include the environmental, social, and economic consequences of risk management activities themselves, and also the opportunities for wider benefit beyond achievement of risk‐reduction goals alone. In the United Kingdom, this interest has led to the formation of a multistakeholder initiative, the UK Sustainable Remediation Forum (SuRF‐UK). This article presents a framework for assessing “sustainable remediation”; describes how it links with the relevant regulatory guidance; reviews the factors considered in sustainability; and looks at the appraisal tools that have been applied to evaluate the wider benefits and impacts of land remediation. The article also describes how the framework relates to recent international developments, including emerging European Union legislation and policy. A large part of this debate has taken place in the “grey” literature, which we review. It is proposed that a practical approach to integrating sustainability within risk‐based contaminated land management offers the possibility of a substantial step forward for the remediation industry, and a new opportunity for international consensus. © 2011 Wiley Periodicals, Inc.     

Journalistic Norms,Cultural Values,and Coverage of Climate Change in the Philippines

Developing nations have tended to have been overlooked in studies of climate reporting. This study is based upon a content analysis of three daily newspapers in the Philippines to examine climate change coverage compared to reporting by Western wire services. In addition, the study draws on individualist–collectivist theory to theorize about differences in reporting between the Philippine and Western wire sources. Despite the historic influence of the American news system on Philippine journalism, the study finds that Western journalistic norms do not describe Philippine climate reporting well and that Filipino-penned articles are more likely to include the value of collectivism rather than individualism. This suggests that national cultural differences may be reflected in climate reporting.     

Traffic noise and executive functioning in urban primary school children: The moderating role of gender

The objective of this study was to examine the relationships between noise and school children's executive functioning (EF). The study included 311 children (146 boys and 165 girls) aged 7–11 years, who lived in the center of Belgrade. Teachers rated children's EF on a standard scale evaluating their ability to work independently in a focused manner to achieve an end goal as well as children's ability to follow directions carefully. Residential noise exposure was estimated in three daytime intervals, one evening interval and two nighttime intervals in the middle of the streets where children lived. School noise exposure was measured on three different school days in front of children's schools. Socioeconomic status (mother's highest level of education and family income) was used as a statistical control. There were no significant main effects of ambient noise levels on EF, however, a significant interaction indicated adverse noise impacts on boy's EF. We discuss possible reasons for male EF vulnerability to noise.