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261.
Human actions can contribute to degradation of coastal environments or they can increase the likelihood that these environments will be restored. Beach nourishment provides a basis for restoration, but ways must be found to add habitat improvement to projects designed for shore protection. This study examines how beach nourishment projects can help reinstate dune landscapes in locations where beaches and dunes had been replaced by static shore protection structures. Dune topography and vegetation on three nourished sites on the northern Adriatic Coast of Italy are compared to a reference site to evaluate changes after beach fill was emplaced. Results reveal how nourishment projects used for shore protection can restore the space available for dunes to form, increase the likelihood of sediment transfers inland and increase the diversity of topography and vegetation. Beach raking prevents formation and growth of hummocky, incipient backshore dunes that would otherwise evolve into a naturally functioning foredune. Sand-trapping fences can speed the process of foredune development but can be counterproductive if they interfere with transport to beach grass (Ammophila littoralis) planted landward of them. Shore protection structures can provide stability and more time for dune evolution on eroding shores, resulting in greater species richness and longer retention of ecological niches. These structures need not be required if re-nourishment occurs frequently enough to provide a beach wide enough to protect against storm wave uprush.  相似文献   
262.
Mutuc MD  Love NG  Vikesland PJ 《Chemosphere》2008,70(8):1390-1398
This study examined the feasibility of using surface catalyzed Fenton treatment to remediate soil and groundwater contaminated by the chlorinated ethers, bis(2-chloroethyl) ether (BCEE) and bis(2-chloroethoxy) methane (BCEM). Parameters that affect the contaminant loss rate such as porewater pH, hydrogen peroxide concentration, and solid/water ratio were systematically evaluated. Batch reactors were set-up utilizing either contaminated or uncontaminated soil, obtained from an industrial site in Moss Point, MS, that was mixed with synthetic groundwater containing the contaminants of interest. The results show an increase in contaminant reduction with a decrease in pH, an increase in hydrogen peroxide concentration, or an increase in the solid/water ratio. For a similar set of conditions, contaminant reduction was greater for systems utilizing contaminated soil as compared to the systems containing uncontaminated soil. In addition, specific oxygen uptake rates (SOURs) were measured for biomass, collected from an activated sludge plant, exposed to different dilutions of untreated and surface catalyzed Fenton treated water to evaluate whether residual BCEE, BCEM, and their co-contaminants as well as their oxidation by-products were potentially inhibitory or can potentially serve as a substrate for the biomass. The measured SOURs show that the surface catalyzed Fenton treatment enhanced the biodegradability of the contaminated groundwater and served as a substrate for the biomass.  相似文献   
263.
A 14‐month pilot‐scale bioventing study, sponsored by the New Hampshire Department of Environmental Services, was conducted by the University of New Hampshire to determine the effects of the time between the contamination event and the onset of bioventing, as well as air flowrate, temperature, and nutrient amendments. Freshly contaminated soil was not readily amenable to bioventing. Bioventing was effective (82–92.5 percent removal) for acclimated soil amended with nutrients at 10 °C and 20 °C for the 275 cm3/min and 140 cm3/min air flowrates, respectively. First order degradation rates after nutrient addition were ?6.11 ± 0.83 (×10?3)/day and ?6.57 ± 1.71 (×10?3)/day, respectively. The results indicate that bioventing will be best applied when the contamination has occurred at least two years before the onset of treatment. © 2014 Wiley Periodicals, Inc.  相似文献   
264.
Recent studies of mortality among coke plant workers indicate that there is an excess of respiratory cancer among men employed at the coke ovens and that the mortality is related to work areas and length of exposure to coal tar effluents, the body of information presented in this paper is directed to categorization of coke oven jobs into different work areas in terms of exposure to coal tar pitch volatiles developing an index of cumulative exposure to investigate the dose-response relationship between exposure and mortality. The exposure data have been taken from a study conducted by the Pennsylvania Department of Health, State Division of Occupational Health, and mortality data are based on a long-term study of steelworkers, conducted by the Department of Biostatistics, University of Pittsburgh. A summary index calculated for each worker combining the level of exposure and length of time exposed indicates that, as expected, both these factors are related to the development of cancer, particularly cancers of the respiratory system.

Conclusions of note are: Measured levels of coal tar pitch volatiles are 2-3 times higher for men who work at the top of coke ovens as compared to men employed at the side of the ovens. Even though the specific carcinogenic element or elements in the coke oven environment are not known at the present time, in-. creasing levels of exposure to coal tar pitch volatiles are related to art increased risk of dying from malignant neoplasms. Further coal tar pitch volatile measurements need to be made and analyses designed which will specify the dose-response relationship more precisely. This will provide information necessary to evaluate the recommended Threshold Limit Value.  相似文献   
265.
ABSTRACT: Human land use is a major source of change in catchments in developing areas. To better anticipate the long‐term effects of growth, land use planning requires estimates of how changes in land use will affect ecosystem processes and patterns across multiple scales of space and time. The complexity of biogeochemical and hydrologic interactions within a basin makes it difficult to scale up from process‐based studies of individual reaches to watershed scales over multiple decades. Empirical models relating land use/land cover (LULC) to water quality can be useful in long‐term planning, but require an understanding of the effects of scale on apparent land use‐water quality relationships. We empirically determined how apparent relationships between water quality and LULC data change at different scales, using LIJLC data from the Willapa Bay watershed (Washington) and water quality data collected along the Willapa and North Rivers. Spatial scales examined ranged from the local riparian scale to total upstream catchment. The strength of the correlations between LTJLC data and longitudinal water quality trends varied with scale. Different water quality parameters also varied in their response to changes in scale. Intermediate scales of land use data generally were better predictors than local riparian or total catchment scales. Additional data from the stream network did not increase the strength of relationships significantly. Because of the likelihood of scale‐induced artifacts, studies quantifying land use‐water quality relationships performed at single scales should be viewed with great caution.  相似文献   
266.
267.
地方环境举措国际理事会 (ICLEI)城市气候保护运动与地方政府一起工作,采用综合的和战略的能源管理手段减少温室气体排放 .对参加气候保护运动的 43个国家的 386个城市地方政府的抽样调查表明,实质性的行动已经改善了地方的能源管理并且减少了温室气体( GHG)排放 .  相似文献   
268.
Allocating costs for hazardous waste site cleanup among potentially responsible parties is unique to the specific circumstances, history, and data for the site. As such, distinct technical approaches are often needed considering the Gore and Torres factors to develop an overall allocation. These factors include both technical and nontechnical considerations that the trier of fact must weigh to arrive at the overall allocation. This article reviews the legal and technical framework in allocating cleanup costs at hazardous waste sites and presents several case histories illustrating the integration of fact, science and law in the final allocation.  相似文献   
269.
This paper examines some of the social processes associated with disaster conditions. Utilising an asset‐based perspective of community capacity, it focuses on four types of normative systems to interpret the ability of communities to manage disasters through market‐, bureaucratic‐, associative‐, and communal‐based norms. Drawing on experience of a wildfire in the Crowsnest Pass region of southwest Alberta, Canada, in 2003, the tensions and compatibilities among these normative systems are evaluated through interviews with 30 community leaders. The results confirm the contributions of all types of social capital to resiliency, the necessity for rapid use of place‐based knowledge, and the importance of communication among all types and levels of agents. In addition, they point to the value of identifying and managing potential conflicts among the normative systems as a means to maximising their contributions. The integration of local networks and groups into the more general disaster response minimised the impacts on health and property.  相似文献   
270.
Khunjar WO  Love NG 《Chemosphere》2011,82(6):917-922
The sorption of carbamazepine (CBZ), iopromide (IOP), trimethoprim (TMP) and 17α-ethinylestradiol (EE2) was evaluated using four biomass types (pure ammonia oxidizing bacterial culture, two heterotrophic enrichment cultures with varying levels of oxygenase activity, and a full-scale nitrifying activated sludge (NAS) culture). CBZ and IOP did not sorb to the four biomass types. EE2 did not sorb to the pure culture but sorbed significantly to the heterotrophic cultures and NAS. TMP sorbed to the heterotrophic cultures and NAS, and was not evaluated for the pure culture. Three floc characteristics (hydrophobicity, median particle size, organic matter content) correlated moderately well with the EE2 organic matter sorption coefficient (KOM,EE2). Zeta potential did not correlate well with KOM,EE2 but did with KOM,TMP, indicating that TMP sorption is more influenced by electrostatic factors than EE2. Once divalent cation-linked exocellular polymeric substances (EPS) were removed from flocs, EE2 and TMP sorption to the non-EPS (cellular) fraction decreased by approximately 50%. The correlation between KOM,EE2 for the non-EPS cellular fraction deteriorated while the correlation between KOM,TMP improved. EE2 seemed to sorb more strongly to EPS protein whereas TMP sorbed equally to polysaccharide and protein EPS. Attempts to develop predictive models were not successful. Pharmaceuticals that sorbed to biomass samples underwent biodegradation whereas those that did not sorb were not biodegraded, suggesting a relationship between sorption and pharmaceutical biotransformation.  相似文献   
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