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101.
102.
Potentially hazardous trace elements such as Cd, Cu, Cr, Ni and Zn are expected to accumulate in biosolids–amended soil and remain in the soil for a long period of time. In this research, uptake of metals by food plants including cabbage, carrot, lettuce and tomato grown on soils 10 years after biosolids application was studied. All the five metals were significantly accumulated in the biosolids-amended soils. The accumulation of metal in soil did not result in significant increase in concentrations of Cu, Cr and Ni in the edible plant tissues. However, the Cd and Zn concentrations of the edible tissues of plants harvested from the biosolids receiving soils were significantly enhanced in comparison with those of the unaffected soils. The plant uptake under Greenfield sandy loam soil was generally higher than those under the Domino clayey loam soil. The metal concentration of edible plant tissue exhibited increasing trends with respect to the concentrations of the ambulated metals. The extents of the increases were plant species dependent. The indigenous soil metals were absorbed by the plants in much higher rates than those of the biosolids–receiving soils. It appeared that the plant uptake of the indigenous soil-borne metal and the added biosolids-borne metals are independent of one another and mathematically are additive.  相似文献   
103.
Although a large number of medical error taxonomies have been published, there is little evidence to suggest that these taxonomies have been systematically compared. This paper describes a study comparing 26 medical error taxonomies using a human factors perspective. The taxonomies were examined to determine if they classified systemic factors of medical errors and if they utilized theoretical error concepts in their classifications. Scope of classification was also examined. It was found that two-thirds of the taxonomies classified systemic factors of medical errors and only a third utilized theoretical error concepts. Medical error taxonomies based on theoretical error concepts were more likely to be generic in applicability and also more likely to classify systemic factors and psychological error mechanisms of medical errors. In addition to terminology, the medical error taxonomies also varied in terms of domain-specificity, granularity, and developmental process. Different medical error taxonomies provide different information; how these differences affect medical error management needs to be investigated.  相似文献   
104.
Herbicide contamination from agriculture is a major issue worldwide, and has been identified as a threat to freshwater and marine environments in the Great Barrier Reef World Heritage Area in Australia. The triazine herbicides are of particular concern because of potential adverse effects, both on photosynthetic organisms and upon vertebrate development. To date a number of bioremediation strategies have been proposed for triazine herbicides, but are unlikely to be implemented due to their reliance upon the release of genetically modified organisms. We propose an alternative strategy using a free-enzyme bioremediant, which is unconstrained by the issues surrounding the use of live organisms. Here we report an initial field trial with an enzyme-based product, demonstrating that the technology is technically capable of remediating water bodies contaminated with the most common triazine herbicide, atrazine.  相似文献   
105.
106.
The introduction of non-native species has accelerated due to increasing levels of global trade and travel, threatening the composition and function of ecosystems. Upon arrival and successful establishment, biological invaders begin to spread and often do so with considerable assistance from humans. Recreational areas can be especially prone to the problem of accidental non-native species transport given the number of visitors that arrive from geographically diverse areas. In this paper, we examine camping permit data to the Apostle Islands National Lakeshore in northwestern Wisconsin, USA, from 1999 to 2007 relative to gypsy moth distribution, phenology and outbreak data. During this time, gypsy moth populations became established in this area ahead of the moving population front of the gypsy moth, suggesting anthropogenic introduction. The permit data revealed that the majority of visitors arrived from outside of the gypsy moth established area. However, there was a consistent yearly trend of visitors that arrived from areas of high gypsy moth populations and who arrived during the gypsy moth life stage (egg masses) most likely to be successfully introduced. Using available data on the gypsy moth and its relationship to camping permit data, we describe how recreational managers could optimize park strategies to mitigate unwanted introductions of the gypsy moth as well as develop analogous strategies for managing other biological invaders in recreational areas.  相似文献   
107.
Abstract

The effects of the herbicide triclopyr (3,5,6‐trichloro‐2‐pyridinyloxyacetic acid) on the mineralization of 2,4‐D (2,4‐dichlorophenoyxacetic acid) in two soils which differed in their histories of prior exposure to the two herbicides were investigated. The relative effects of triclopyr on 2,4‐D mineralization and most probable numbers of 2,4‐D degraders were dependent upon the soil. Triclopyr was shown to increase 2,4‐D mineralization rates in a soil which had been exposed to both 2,4‐D and triclopyr, but decreased the mineralization rate of 2,4‐D and inhibited the increase of most probable numbers of 2,4‐D degraders in a soil that had not been directly exposed to either herbicide.  相似文献   
108.
Some of the largest concentrations of dugongs (Dugong dugon) occur in the coastal waters of eastern Cape York Peninsula, Queensland, Designation of the Great Barrier Reef Marine Park has prompted the development of a program for management of dugong hunting by the aboriginal communities of the region. Assessment of the population by aerial surveys combined with monitoring of the aboriginal hunters' harvest suggest that the take is well below the sustainable yield. However, the reproductive rate of dugongs is so low that it will be a decade before the status of the population can be established. Therefore, a conservative management policy for dugongs is recommended while acknowledging the rights of traditional hunters. Greater participation of the aboriginal communities in the management program is sought to overcome initial misunderstandings and hostility.  相似文献   
109.
This research demonstrates the contribution of phenomenological inquiry within the realm of geographic and environmental planning. The contention is that a focus on the wide range of individual meanings and values ascribed to landscapes, a marginalized element in many planning assessments, can bring out data to more substantively inform decision making, A case study of user meanings imparted to residual waterfront land in Hoboken, New Jersey, USA, suggests that such property provides an array of amenities to residents. Most importantly, it expands the range of recreational activities, creates visual relief from the monotonous urban milieu, and provides scenic vistas to promote an awareness of the quality of life still possible in cities. The study concludes that planners can use phenomenology to generate data for more judicious decision making.  相似文献   
110.
ABSTRACT: Literature on the flood hazard/residential land market relationship is full of contradictory findings, many of which are counter-intuitive to the belief that flooding has a negative impact on house prices. This research advances a conceptual framework through which these relationships might be re-examined. Based on the expected utility model, the theoretical framework integrates the economic notion of capitalization with spatial and temporal characteristics of the flood hazard. Four communities with different flood regimes are used to test the effect of flooding on the residential real estate market. Results show that, (1) there is an identifiable relationship between characteristics of the flood hazard and changes in house values; (2) the length of the recovery period is dependent on characteristics and expectations of flooding, attributes of the real estate market, and availability of capital to fuel recovery; and (3) dynamics of the urban market and spatial extent of the flood hazard influence these relationships. Further research is now necessary to examine these findings under different spatial, temporal, hydrological, and socio-economic conditions.  相似文献   
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