Use of metal-reducing bacteria for bioremediation of soil contaminated with mixed organic and inorganic pollutants

Mixed contamination by organic and inorganic compounds in soil is a serious problem for remediation. Most laboratory studies and field-scale trials focused on individual contaminant in the past. For concurrent bioremediation by biodegradation and bioleaching processes, we tested metal-reducing microorganism, Geobacter metallireducens. In order to prove the feasibility of the coupled process, multiple-contaminated soil was prepared. Mineralogical analyses have shown the existence of labile forms of As(V) as amorphous and/or weakly sorbed phases in the secondary Fe oxides. In the biotic experiment using G. metallireducens, biodegradation of toluene and bioleaching of As by bacteria were observed simultaneously. Bacteria accelerated the degradation rate of toluene with reductive dissolution of Fe and co-dissolution of As. Although there have been many studies showing each individual process, we have shown here that the idea of concurrent microbial reaction is feasible. However, for the practical use as a remediation technology, more details and multilateral evaluations are required in future studies.     

Multi-scale marine biodiversity patterns inferred efficiently from habitat image processing

Cost-effective proxies of biodiversity and species abundance, applicable across a range of spatial scales, are needed for setting conservation priorities and planning action. We outline a rapid, efficient, and low-cost measure of spectral signal from digital habitat images that, being an effective proxy for habitat complexity, correlates with species diversity and requires little image processing or interpretation. We validated this method for coral reefs of the Great Barrier Reef (GBR), Australia, across a range of spatial scales (1 m to 10 km), using digital photographs of benthic communities at the transect scale and high-resolution Landsat satellite images at the reef scale. We calculated an index of image-derived spatial heterogeneity, the mean information gain (MIG), for each scale and related it to univariate (species richness and total abundance summed across species) and multivariate (species abundance matrix) measures of fish community structure, using two techniques that account for the hierarchical structure of the data: hierarchical (mixed-effect) linear models and distance-based partial redundancy analysis. Over the length and breadth of the GBR, MIG alone explained up to 29% of deviance in fish species richness, 33% in total fish abundance, and 25% in fish community structure at multiple scales, thus demonstrating the possibility of easily and rapidly exploiting spatial information contained in digital images to complement existing methods for inferring diversity and abundance patterns among fish communities. Thus, the spectral signal of unprocessed remotely sensed images provides an efficient and low-cost way to optimize the design of surveys used in conservation planning. In data-sparse situations, this simple approach also offers a viable method for rapid assessment of potential local biodiversity, particularly where there is little local capacity in terms of skills or resources for mounting in-depth biodiversity surveys.     

Sexual conflict in a polygynous primate: costs and benefits of a male-imposed mating system

Fundamental reproductive interests dictate that females generally benefit most from mate selectivity and males from mate quantity. This can create conflict between the sexes and result in sexual coercion: male use of aggression to garner mating success at a cost to females. Potential fitness costs of sexual coercion, however, can be difficult to measure. Here, we demonstrate benefits to males and costs to females of female defense polygyny in wild hamadryas baboons, cercopithecoid primates in which females are coercively transferred among social units by males, restricting both female choice and bonding among female kin. Of all coercive transfers (takeovers) of females with young infants, 67 % were followed by infant mortality, which was significantly more likely to occur after takeovers than at other times. As expected, infant mortality decreased time to subsequent conception but lengthened intervals between surviving infants. Following infant survival, whether a female had experienced a takeover after the previous birth was a significant predictor of subsequent interbirth interval, with interbirth intervals of females remaining with the same male between births being significantly shorter than those of females incurring takeovers between births. Together, these results reveal that takeovers increase the chance of infant mortality while delaying subsequent conception. Male-driven female defense polygyny in this species is thus costly to females in two ways. These results demonstrate that reproductive strategies benefitting males can evolve despite substantial costs to females. These costs may be mitigated over the long term, however, by female counterstrategies and protective behavior by males.     

Policy planning under uncertainty: efficient starting populations for simulation-optimization methods applied to municipal solid waste management

Evolutionary simulation-optimization (ESO) techniques can be adapted to model a wide variety of problem types in which system components are stochastic. Grey programming (GP) methods have been previously applied to numerous environmental planning problems containing uncertain information. In this paper, ESO is combined with GP for policy planning to create a hybrid solution approach named GESO. It can be shown that multiple policy alternatives meeting required system criteria, or modelling-to-generate-alternatives (MGA), can be quickly and efficiently created by applying GESO to this case data. The efficacy of GESO is illustrated using a municipal solid waste management case taken from the regional municipality of Hamilton-Wentworth in the Province of Ontario, Canada. The MGA capability of GESO is especially meaningful for large-scale real-world planning problems and the practicality of this procedure can easily be extended from MSW systems to many other planning applications containing significant sources of uncertainty.     

Interrole conflict and marital functioning amongst employed fathers

While the influence of maternal interrole conflict on marital functioning has been investigated, the issue of fathers' interrole conflict has been neglected. Consequently, 67 fathers' (M age = 38.51 years) interrole conflict and marital adjustment are investigated. In addition, the moderating role of personality hardiness is assessed. Using multiple moderator regression and sub-group analyses, hardiness was shown to moderate negative effects of interrole conflict on marital adjustment. Conceptual and practical implications of these findings are discussed.     

Snowblower injuries in Vermont, 1981–1984

The Vermont Department of Health carried out two studies of snowblower injuries in Vermont during the winters of 1982–1983 and 1983–1984. The first was a case-control study in which we assessed risk factors that predisposed operators to injury during snowblower use. We found 20 persons who had been injured by snowblowers and matched 28 controls to these by neighborhood. In this study, owning a snowblower for 1 year or less and having operated a snowblower for 10 days or less in one's lifetime were significantly associated with injury. The second study was population-based. We estimated that approximately 1.5% of Vermont residents owned snowblowers during the winter of 1982–1983 and that, among snowblower owners, injuries occurred at a rate of 1.3/1,000 person-years of ownership (0.1% chance of injury).     

Buoyancy and turbulence-driven atmospheric circulation over urban areas

In the buoyancy and turbulence-driven atmospheric circulations (BTDAC) that occur over urban areas where the approach means wind speeds are very low (less than turbulent fluctuations and typically < 3 m/sec), the surface temperatures are significantly higher than those in the external rural areas, and the atmosphere above the mixing layer is stably stratified. In this paper, the mechanisms of BTDAC formation are studied through laboratory experiments and modelling, with additional low-level inflow from external rural areas and a divergent outflow in the opposite direction in the upper part of the mixed layer. Strong turbulent plumes in the central region mix the flow between lower and higher levels up to the inversion height. There are shear-driven turbulent eddies and weaker buoyant plumes around the periphery of the urban area. As the approach flow is very weak, the recirculating streamlines within the dome restrict the ventilation, and the dispersion of pollution emitted from sources below the inversion height leading to a rise in the mean concentration. Low-level air entrained from rural areas can, however, improve ventilation and lower this concentration. This trend can also be improved if the recirculating structure of the BTDAC flow pattern over urban areas breaks down as a result of the surface temperature distribution not being symmetrical, or as the approach wind speed increases to a level comparable with the mean velocity of circulation, or (except near the equator) the urban area is large enough that the Coriolis acceleration is significant.     

额济纳绿洲生态环境保护对策的探讨

黑河下游额济纳河沿岸绿洲是阿拉善独特的三道生态屏障——额济纳河沿岸绿洲、横贯东西绵延800多公里梭梭林带、贺兰山天然次生林之一。三道生态屏障同时也是我国西北地区的一条重要生态防线。但由于气候旱化和对动植物资源的不合理开发利用等因素的共同作用,目前黑河下游额济纳河沿岸绿洲生态功能退化严重,生态防护功能受损。为改善黑河下游额济纳河沿岸绿洲的生态环境状况,恢复额济纳绿洲生态功能,需要尊重自然规律,遵循生态学原理,在可持续发展原则指导下合理开发、利用自然资源,加大环保监管力度,综合运用经济、工程、法制、宣传等规划管理措施和手段加强生态环境保护与建设,保护额济纳绿洲生态屏障。