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111.
Managing risk by adapting long-lived infrastructure to the effects of climate change must become a regular part of planning for water supply, sewer, wastewater treatment, and other urban infrastructure during this century. The New York City Department of Environmental Protection (NYCDEP), the agency responsible for managing New York City’s (NYC) water supply, sewer, and wastewater treatment systems, has developed a climate risk management framework through its Climate Change Task Force, a government-university collaborative effort. Its purpose is to ensure that NYCDEP’s strategic and capital planning take into account the potential risks of climate change—sea-level rise, higher temperature, increases in extreme events, changes in drought and flood frequency and intensity, and changing precipitation patterns—on NYC’s water systems. This approach will enable NYCDEP and other agencies to incorporate adaptations to the risks of climate change into their management, investment, and policy decisions over the long term as a regular part of their planning activities. The framework includes a 9-step Adaptation Assessment procedure. Potential climate change adaptations are divided into management, infrastructure, and policy categories, and are assessed by their relevance in terms of climate change time-frame (immediate, medium, and long term), the capital cycle, costs, and other risks. The approach focuses on the water supply, sewer, and wastewater treatment systems of NYC, but has wide application for other urban areas, especially those in coastal locations.  相似文献   
112.
This paper reports the findings of a two‐wave longitudinal study investigating relationships between organizational and individual career management activities and organizational commitment in the early years of graduate careers. Several hypotheses are tested and receive mixed support. High organizational commitment predicts the practice of career management activities by graduates to further their career within the organization while low commitment is closely associated with behaviour aimed at furthering the career outside the organization. Graduates who manage their own careers also receive more career management help from their employer. This suggests that there may be the potential for employers to create a ‘virtuous circle’ of career management in which individual and organizational activities complement each other. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   
113.
The article summarizes outcomes of a biomass study conducted in a young speckled alder plantation on a cold mountain site. At this location, the previously existing old forest was clear felled because of damage from air pollution, and present-day surface humus is in need of restoration. The intention of this study was to quantify the biomass and nutrients accumulated by alders and their components and assess whether the initial fertilization resulted in increased biomass production and nutrient accumulation in the biomass. Besides the control, two fertilized treatments were installed. In the surface treatment (SUT), the amendment was applied as a base dressing in small circles around trees. In the planting-hole treatment (PHT), the amendment was incorporated into soil inside the planting holes. Five growth seasons after planting and fertilization, six alders from each treatment were harvested including roots. Their biomass was quantified and analyzed for macroelements. The greatest pool of dry mass (DM) was branches in the control and stem wood in the fertilized treatments. The greatest pools of macroelements were leaves and branches. The most pronounced effects of fertilization were recorded in the DM and consequently in the absolute quantities of nutrients. The DM of an average tree in the control, SUT, and PHT was 85, 226, and 231 g, respectively. The absolute contents of nutrients per tree in the fertilized treatments showed the following increases, as compared with the control: (N) 2.5–2.6 times; (P) 1.6–2.4 times; (K) 1.8–2.1 times; and (Mg) 1.8–2.0 times, respectively. Speckled alder responded positively to fertilization.  相似文献   
114.

During the 1990s the social scientific literature on local opposition to proposed developments has moved from a focus on individual motives to a concern with the social causes and significance of such protest. However, the language of NIMBYism is still widely used by researchers. Drawing on data from a case study of local responses to a proposed new road the central role that the language of NIMBY plays within siting disputes is illustrated, and it is concluded that academics interested in understanding the dynamics and process of local development disputes might usefully study participants' use of NIMBY, but should distance themselves from the activity of attributing NIMBYism to certain parties. In addition those concerned with managing, mediating or resolving local disputes should also steer clear of the language of NIMBY and engage with the diversity and complexity of local concerns and interests.  相似文献   
115.
116.
This paper focuses on the issues arising from Local Agenda 21 where the role of local authorities is seen as vital in promoting and achieving sustainable development. The implications of the current forms of public sector restructuring for local authorities, and in particular the consequences of the requirement to contract out the delivery and management of traditional environmental services such as grounds maintenance are considered. The paper concludes that the ongoing processes of local government restructuring, together with the removal of many functions from local democratic control, are reducing the capacity of local communities to respond positively to the demands of Local Agenda 21.  相似文献   
117.
Badgers are carnivores that show considerable variation in their social and spatial organization. At the westernmost part of their range, in Britain and Ireland, variation in spatial organization appears to be determined by the availability of resources. However, the majority of studies has focussed at one end of the social/spatial spectrum, where population densities are high and adjacent territories are contiguous and non-overlapping. To examine whether the same limiting factors appear to apply across a wider range of badger densities, we established a study site in a predominantly coniferous habitat within an upland area of northeast England, where population densities were predicted to be low. Seasonal home ranges of individual badgers were largest in autumn, followed by summer and spring, then winter. This pattern is reflective of the likely seasonal changes in food availability within the area, as opposed to being related to breeding patterns. There were also significant correlations between territory size and the number of grassland patches (positive) and the proportion of grassland (negative), which are consistent with predictions from the Resource Dispersion Hypothesis. Although badgers at the site were living at low to moderate densities relative to many other studied populations in Britain, they showed patterns of spatial organization that were close to those of high-density populations. The nature of the relationship between resource availability and abundance patterns is likely to have important consequences for the conservation and management of badgers and other species that show flexible spatial organization.  相似文献   
118.
Soil is an important compartment in the environmental cycling of trichloroacetic acid (TCA), but soil TCA concentration is a methodologically defined quantity; analytical methods either quantify TCA in an aqueous extract of the soil, or thermally decarboxylate TCA to chloroform in the whole soil sample. The former may underestimate the total soil TCA, whereas the latter may overestimate TCA if other soil components (e.g. humic material) liberate chloroform under the decarboxylation conditions. The aim of this work was to show that extraction and decarboxylation methods yield different TCA concentrations because the decarboxylation method can also determine "bound" TCA. Experiments with commercial humic acid solutions showed there was no additional chloroform formation under decarboxylation conditions, and that all TCA in a TCA-humic acid mixture could be quantitatively determined (108 +/- 13%). Anion exchange resin was used as a provider of solid-phase TCA binding; only 5 +/- 1% of a TCA solution mixed with the resin was present in the aqueous extract subsequently separated from the resin, yet the decarboxylation method yielded mass balance (123 +/- 22%) with TCA remaining in the resin. In aqueous extraction of a range of soil samples (with or without added TCA spike), the decarboxylation method was able to satisfactorily account for TCA in the extractant + residue post-extraction, compared with whole-soil TCA (+ spike) pre-extraction: e.g. mass balances for unspiked soil from Sikta spruce and larch forest were 99 +/- 8% and 93 +/- 6%, respectively, and for TCA-spiked forest and agricultural soils were 114 +/- 13% and 102 +/- 2%. In each case recovery of TCA in the extractant was substantially less than 100%(<20% for unspiked soils, <55% for spiked soils). Extraction efficiencies were generally lower in more organic soils. The results suggest that analytical methods which utilise aqueous extraction may underestimate whole-soil TCA concentrations. Application of both methodologies together may enhance insight into TCA behaviour in soil.  相似文献   
119.
The current study analyzes the contribution of 10 water quality parameters (including pH, turbidity, conductivity, total dissolved solids (TDS), hardness, total organic carbon (TOC), alkalinity, calcium ions, chlorides and sulfates) to corrosion extent of stainless steel valves taken from different locations in a reverse osmosis system of a reclaimed water plant. The valves were in service for 5 years. Raman spectroscopy and X-ray photoelectron spectroscopy analyses are conducted to quantify corrosion products on different valves under various water quality conditions. On that basis, bivariate and multivariate regression analyses between the 10 water quality parameters and the corrosion extent of valve specimens (represented by metal loss percentage (MLP) values) are carried out to check the contribution of those water quality parameters to MLP. The results indicate that the proportions of metal oxides as corrosion products vary according to the corrosion extent of the valves. Although no linear correlation is found, all 10 water quality parameters except for pH show a significant positive correlation with the MLP values of the valve specimens. Moreover, results of multivariate regression suggest that the variation of MLP can be explained by turbidity, TDS, TOC and sulfates. A positive contribution of turbidity, TDS and TOC to MLP is observed, whereas the contribution of sulfates is negative. The results from the current work help to identify the reasons for water quality-induced failure of stainless steel equipment in RO systems.  相似文献   
120.
Stainless steels generally have extremely good corrosion resistance, but are still susceptible to pitting corrosion. As a result, corrosion scales can form on the surface of stainless steel after extended exposure to aggressive aqueous environments. Corrosion scales play an important role in affecting water quality. These research results showed that interior regions of stainless steel corrosion scales have a high percentage of chromium phases. We reveal the morphology, micro-structure and physicochemical characteristics of stainless steel corrosion scales. Stainless steel corrosion scale is identified as a podiform chromite deposit according to these characteristics, which is unlike deposit formed during iron corrosion. A conceptual model to explain the formation and growth of stainless steel corrosion scale is proposed based on its composition and structure. The scale growth process involves pitting corrosion on the stainless steel surface and the consecutive generation and homogeneous deposition of corrosion products, which is governed by a series of chemical and electrochemical reactions. This model shows the role of corrosion scales in the mechanism of iron and chromium release from pitting corroded stainless steel materials. The formation of corrosion scale is strongly related to water quality parameters. The presence of HClO results in higher ferric content inside the scales. Cl and SO42 − ions in reclaimed water play an important role in corrosion pitting of stainless steel and promote the formation of scales.  相似文献   
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