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861.
The objectives of this study were to elucidate the effects of soil amendments [Ferrous sulfate (FeII), red mud, FeII with calcium carbonate (FeII/L) or red mud (RM/F), zero-valent iron (ZVI), furnace slag, spent mushroom waste and by-product fertilizer] on arsenic (As)
stabilization and to establish relationships between soil properties, As fractions and soil enzyme activities in amended As-rich
gold mine tailings (Kangwon and Keumkey). Following the application of amendments, a sequential extraction test and evaluation
of the soil enzyme activities (dehydrogenase and β-glucosidase) were conducted. Weak and negative relationships were observed between water-soluble As fractions (AsWS) and oxalate extractable iron, while AsWS was mainly affected by dissolved organic carbon in alkaline tailings sample (Kangwon) and by soil pH in acidic tailings sample
(Keumkey). The soil enzyme activities in both tailings were mainly associated with AsWS. Principal component and multiple regression analyses confirmed that AsWS was the most important factor to soil enzyme activities. However, with some of the treatments in Keumkey, contrary results
were observed due to increased water-soluble heavy metals and carbon sources. In conclusion, our results suggest that to simultaneously
achieve decreased AsWS and increased soil enzyme activities, Kangwon tailings should be amended with FeII, FeII/L or ZVI, while only ZVI or RM/F would be suitable for Keumkey tailings. Despite the limitations of specific soil samples,
this result can be expected to provide useful information on developing a successful remediation strategy of As-contaminated
soils. 相似文献
862.
Steen DA McClure CJ Brock JC Rudolph DC Pierce JB Lee JR Humphries WJ Gregory BB Sutton WB Smith LL Baxley DL Stevenson DJ Guyer C 《Ecological applications》2012,22(4):1084-1097
Habitat loss and degradation are thought to be the primary drivers of species extirpations, but for many species we have little information regarding specific habitats that influence occupancy. Snakes are of conservation concern throughout North America, but effective management and conservation are hindered by a lack of basic natural history information and the small number of large-scale studies designed to assess general population trends. To address this information gap, we compiled detection/nondetection data for 13 large terrestrial species from 449 traps located across the southeastern United States, and we characterized the land cover surrounding each trap at multiple spatial scales (250-, 500-, and 1000-m buffers). We used occupancy modeling, while accounting for heterogeneity in detection probability, to identify habitat variables that were influential in determining the presence of a particular species. We evaluated 12 competing models for each species, representing various hypotheses pertaining to important habitat features for terrestrial snakes. Overall, considerable interspecific variation existed in important habitat variables and relevant spatial scales. For example, kingsnakes (Lampropeltis getula) were negatively associated with evergreen forests, whereas Louisiana pinesnake (Pituophis ruthveni) occupancy increased with increasing coverage of this forest type. Some species were positively associated with grassland and scrub/shrub (e.g., Slowinski's cornsnake, Elaphe slowinskii) whereas others, (e.g., copperhead, Agkistrodon contortrix, and eastern diamond-backed rattlesnake, Crotalus adamanteus) were positively associated with forested habitats. Although the species that we studied may persist in varied landscapes other than those we identified as important, our data were collected in relatively undeveloped areas. Thus, our findings may be relevant when generating conservation plans or restoration goals. Maintaining or restoring landscapes that are most consistent with the ancestral habitat preferences of terrestrial snake assemblages will require a diverse habitat matrix over large spatial scales. 相似文献
863.
Rodhouse TJ Ormsbee PC Irvine KM Vierling LA Szewczak JM Vierling KT 《Ecological applications》2012,22(4):1098-1113
Bats face unprecedented threats from habitat loss, climate change, disease, and wind power development, and populations of many species are in decline. A better ability to quantify bat population status and trend is urgently needed in order to develop effective conservation strategies. We used a Bayesian autoregressive approach to develop dynamic distribution models for Myotis lucifugus, the little brown bat, across a large portion of northwestern USA, using a four-year detection history matrix obtained from a regional monitoring program. This widespread and abundant species has experienced precipitous local population declines in northeastern USA resulting from the novel disease white-nose syndrome, and is facing likely range-wide declines. Our models were temporally dynamic and accounted for imperfect detection. Drawing on species-energy theory, we included measures of net primary productivity (NPP) and forest cover in models, predicting that M. lucifugus occurrence probabilities would covary positively along those gradients. Despite its common status, M. lucifugus was only detected during -50% of the surveys in occupied sample units. The overall naive estimate for the proportion of the study region occupied by the species was 0.69, but after accounting for imperfect detection, this increased to -0.90. Our models provide evidence of an association between NPP and forest cover and M. lucifugus distribution, with implications for the projected effects of accelerated climate change in the region, which include net aridification as snowpack and stream flows decline. Annual turnover, the probability that an occupied sample unit was a newly occupied one, was estimated to be low (-0.04-0.14), resulting in flat trend estimated with relatively high precision (SD = 0.04). We mapped the variation in predicted occurrence probabilities and corresponding prediction uncertainty along the productivity gradient. Our results provide a much needed baseline against which future anticipated declines in M. lucifugus occurrence can be measured. The dynamic distribution modeling approach has broad applicability to regional bat monitoring efforts now underway in several countries and we suggest ways to improve and expand our grid-based monitoring program to gain robust insights into bat population status and trend across large portions of North America. 相似文献
864.
865.
Busch J Dave R Hannah L Cameron A Rasolohery A Roehrdanz P Schatz G 《Conservation biology》2012,26(3):408-419
We examined the cost of conserving species as climate changes. We used a Maxent species distribution model to predict the ranges from 2000 to 2080 of 74 plant species endemic to the forests of Madagascar under 3 climate scenarios. We set a conservation target of achieving 10,000 ha of forest cover for each species and calculated the cost of achieving this target under each scenario. We interviewed managers of projects to restore native forests and conducted a literature review to obtain the net present cost per hectare of management actions to maintain or establish forest cover. For each species, we added hectares of land from lowest to highest cost per additional year of forest cover until the conservation target was achieved throughout the time period. Climate change was predicted to reduce the size of species' ranges, the overlap between species' ranges and existing or planned protected areas, and the overlap between species' ranges and existing forest. As a result, climate change increased the cost of achieving the conservation target by necessitating successively more costly management actions: additional management within existing protected areas (US$0-60/ha); avoidance of forest degradation (i.e., loss of biomass) in community-managed areas ($160-576/ha); avoidance of deforestation in unprotected areas ($252-1069/ha); and establishment of forest on nonforested land within protected areas ($802-2710/ha), in community-managed areas ($962-3226/ha), and in unprotected areas ($1054-3719/ha). Our results suggest that although forest restoration may be required for the conservation of some species as climate changes, it is more cost-effective to maintain existing forest wherever possible. 相似文献
866.
Kim Kyeong Ho Bae Min A. Lee Man Sig Park Hung-Suck Baek Jae Ho 《Journal of Material Cycles and Waste Management》2021,23(1):121-129
Journal of Material Cycles and Waste Management - Organic binders that are used in sand casting emit high amounts of hazardous pollutants and volatile organic compounds during the casting process.... 相似文献
867.
Journal of Material Cycles and Waste Management - Globally, there is rising awareness of the severity of the plastic waste problem, and the implications of plastics accumulation in the environment.... 相似文献
868.
Kim Ye Eun Byun Mi Yeon Lee Kwan-Young Lee Man Sig 《Journal of Material Cycles and Waste Management》2021,23(4):1657-1664
Journal of Material Cycles and Waste Management - The recovery of Pd from spent catalysts has been gaining attention due to its high economic value and limited availability in nature. To recover... 相似文献
869.
A relationship-oriented culture predominates in the Greater China region, where it is more important than in Western countries. Some characteristics of this culture influence strongly the organizational structure and interactions among members in an organization. This study aimed to explore the possible influence of relationships on safety management in relationship-oriented cultures. We hypothesized that organizational factors (management involvement and harmonious relationships) within a relationship-oriented culture would influence supervisory work (ongoing monitoring and task instructions), the reporting system (selective reporting), and teamwork (team communication and co-ordination) in safety management at a group level, which would in turn influence individual reliance complacency, risk awareness, and practices. We distributed a safety climate questionnaire to the employees of Taiwanese high-risk industries. The results of structural equation modeling supported the hypothesis. This article also discusses the findings and implications for safety improvement in countries with a relationship-oriented culture. 相似文献
870.
Environmental epidemiology and health risk and impact assessment have long grappled with problems of uncertainty in data and
their relationships. These uncertainties have become more challenging because of the complex, systemic nature of many of the
risks. A clear framework defining and quantifying uncertainty is needed. Three dimensions characterise uncertainty: its nature,
its location and its level. In terms of its nature, uncertainty can be both intrinsic and extrinsic. The former reflects the
effects of complexity, sparseness and nonlinearity; the latter arises through inadequacies in available observational data,
measurement methods, sampling regimes and models. Uncertainty occurs in three locations: conceptualising the problem, analysis
and communicating the results. Most attention has been devoted to characterising and quantifying the analysis—a wide range
of statistical methods has been developed to estimate analytical uncertainties and model their propagation through the analysis.
In complex systemic risks, larger uncertainties may be associated with conceptualisation of the problem and communication
of the analytical results, both of which depend on the perspective and viewpoint of the observer. These imply using more participatory
approaches to investigation, and more qualitative measures of uncertainty, not only to define uncertainty more inclusively
and completely, but also to help those involved better understand the nature of the uncertainties and their practical implications. 相似文献