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Different Management Strategies (different + management_strategy)
Selected AbstractsSediment quality assessment and dredged material management in Spain: Part II, analysis of action levels for dredged material management and application to the bay of Cádiz,INTEGRATED ENVIRONMENTAL ASSESSMENT AND MANAGEMENT, Issue 4 2007Manuel Alvarez-Guerra Abstract When sediments are removed from aquatic bottoms, they turn into dredged material that must be managed, taking into account its environmental impact. In Part II of this 2-part paper addressing sediment quality assessment and dredged material management in Spain, legislation and criteria used to regulate dredged material disposal at sea in different European countries are reviewed, as are action levels (ALs) derived by different countries used to evaluate management of dredged sediments from Cádiz Bay located on the South Atlantic coast of Spain. Comparison of ALs established for dredged material disposal by different countries reveals orders of magnitude differences in the values established for the same chemical. In Part I of this 2-part paper, review of different sediment quality guideline (SQG) methods used to support sediment quality assessments indicated a great heterogeneity of SQGs, both with regard to the numeric values for a particular chemical and the number of substances for which SQGs have been derived. The analysis highlighted the absence of SQGs for priority substances identified in current European Union water policy. Here, in Part II, the ALs are applied to dredged sediments from Cádiz Bay (South Atlantic coast of Spain), evidencing that the heterogeneity of ALs implemented in the reviewed countries could determine different management strategies. The application of other measurements such as bioassays might offer information useful in identifying a cost-effective management option in a decision-making framework, especially for dredged material with intermediate chemical concentrations. [source] A framework for assessing the biodiversity and fishery aspects of marine reservesJOURNAL OF APPLIED ECOLOGY, Issue 4 2009Phillip S. Levin Summary 1. ,Resource management agencies are often charged with managing natural resources for economic and social goals, while also protecting and conserving biodiversity and ecosystem function. However, this may not always be possible. Ecosystem-based management is frequently suggested as a way to achieve multiple objectives in resource management and requires that trade-offs among conflicting objectives be identified and an effective means to utilize these trade-offs developed. 2. ,We examine the relationship between area and species richness in a diverse assemblage of fishes along the US West Coast and then use parameters from this relationship as input for a model that considers trade-offs between fisheries yield and the number of species protected by different management strategies. 3. ,The species,area relationship (S = cAz) for fishes along the US Pacific coast is well described by the relationship S = 16·18A0·226. 4. ,There are nearly linear trade-offs between diversity and yield when fishing effort is low. However, the trade-offs become nonlinear as fishing effort increases and imposing MPAs increases both the conservation and fisheries value of the system when the system is overfished. 5. ,Synthesis and applications. Solving conflicts between fisheries and conservation requires attention as to how conservation benefits accrue as fishing effort is reduced. However, scientists often lack quantitative information about the trade-offs inherent in human activities such as fisheries. The approach we develop here can begin to help frame the questions to be posed and evaluate the likely consequences of different management options. [source] Fillet yield and fat content in common carp (Cyprinus carpio) produced in three Austrian carp farms with different culture methodologiesJOURNAL OF APPLIED ICHTHYOLOGY, Issue 5 2009C. Bauer Summary The fat content and fillet yield of common carp (Cyprinus carpio) from three carp farms were investigated with respect to pond management and overall climatic conditions. The mean fat content of the trimmed fillet varied from 2.7 to 6.9% and differed significantly among the three facilities (P < 0.001). It is suggested that differences in the fillet fat content may be based on the climatic conditions as well as the different management strategies (feeding, stocking biomass). The mean fillet yield was calculated as 34.0,39.0%. No significant correlation between fish weight and fillet yield (, = ,0.16) was found. Results suggest that producing smaller fish for fillets of serving size may lead to a higher production and conclude with lower production risks and costs. [source] Pathophysiological characteristics of patients with non-erosive reflux disease differ from those of patients with functional heartburnALIMENTARY PHARMACOLOGY & THERAPEUTICS, Issue 1 2004M. Frazzoni Summary Background :,Patients with endoscopy-negative heartburn can be subdivided into non-erosive reflux disease and functional heartburn on the basis of abnormal and normal, respectively, oesophageal acid exposure. Different pathophysiological characteristics could explain the reportedly low efficacy of proton pump inhibitors in functional heartburn. Aim :,To assess if non-erosive reflux disease and functional heartburn are pathophysiologically distinguishable. Methods :,Oesophageal manometry and pH-monitoring were performed in 145 patients with endoscopy-negative heartburn, in 72 patients with erosive reflux disease, in 58 patients with complicated reflux disease, and in 60 controls. Results :,Patients with non-erosive reflux disease (84 cases) and functional heartburn (61 cases) differed with regard to the prevalence of hiatal hernia (49% vs. 31%, P = 0.008), the mean lower oesophageal sphincter tone (18.5 vs. 28.4 mmHg, P < 0.05), and the number of upright diurnal acid refluxes lasting more than 5 min (3.6 vs. 0.37, P < 0.05). The results were very close in thenon-erosive reflux disease, erosive reflux disease and complicated reflux disease groups, whilst patients with functional heartburn were indistinguishable from controls. Conclusions :,Pathophysiological characteristics typical of gastro-oesophageal reflux disease are found in patients with non-erosive reflux disease but not in patients with functional heartburn. This could explain the reportedly low efficacy of proton pump inhibitors in functional heartburn and suggests considering different management strategies. [source] Quality of life compared during pharmacological treatments and clinical monitoring for non-localized prostate cancer: a randomized controlled trialBJU INTERNATIONAL, Issue 7 2004H.J. Green OBJECTIVES To investigate the effects of different management strategies for non-localized prostate cancer on men's quality of life and cognitive functioning. PATIENTS, SUBJECTS AND METHODS Men with prostate cancer were randomly assigned to one of four treatment arms: leuprorelin, goserelin, cyproterone acetate (CPA), or close clinical monitoring. In a repeated-measures design, men were assessed before treatment (baseline) and after 6 and 12 months of treatment. A community comparison group of men of the same age with no prostate cancer participated for the same length of time. The men were recruited from public and private urology departments from university teaching hospitals. All those with prostate cancer who were eligible for hormonal therapy had no symptoms requiring immediate therapy. In all, 82 patients were randomized and 62 completed the 1-year study, and of the 20 community participants, 15 completed the study. The main outcome measures were obtained from questionnaires on emotional distress, existential satisfaction, physical function and symptoms, social and role function, subjective cognitive function, and sexual function, combined with standard neuropsychological tests of memory, attention, and executive functions. RESULTS Sexual dysfunction increased for patients on androgen-suppressing therapies, and emotional distress increased in those assigned to CPA or close clinical monitoring. Compared with before treatment there was evidence of an adverse effect of leuprorelin, goserelin, and CPA on cognitive function. Conclusions In deciding the timing of androgen suppression therapy for prostate cancer, consideration should be given to potential adverse effects on quality of life and cognitive function. [source] Conservation implications of complex population structure: lessons from the loggerhead turtle (Caretta caretta)MOLECULAR ECOLOGY, Issue 8 2005B. W. BOWEN Abstract Complex population structure can result from either sex-biased gene flow or population overlap during migrations. Loggerhead turtles (Caretta caretta) have both traits, providing an instructive case history for wildlife management. Based on surveys of maternally inherited mtDNA, pelagic post-hatchlings show no population structure across the northern Atlantic (,ST < 0.001, P = 0.919), subadults in coastal habitat show low structure among locations (,ST = 0.01, P < 0.005), and nesting colonies along the southeastern coast of the United States have strong structure (,ST = 0.42, P < 0.001). Thus the level of population structure increases through progressive life history stages. In contrast, a survey of biparentally inherited microsatellite DNA shows no significant population structure: RST < 0.001; FST = 0.002 (P > 0.05) across the same nesting colonies. These results indicate that loggerhead females home faithfully to their natal nesting colony, but males provide an avenue of gene flow between regional nesting colonies, probably via opportunistic mating in migratory corridors. As a result, all breeding populations in the southeastern United States have similar levels of microsatellite diversity (HE = 0.70,0.89), whereas mtDNA haplotype diversity varies dramatically (h = 0.00,0.66). Under a conventional interpretation of the nuclear DNA data, the entire southeastern United States would be regarded as a single management unit, yet the mtDNA data indicate multiple isolated populations. This complex population structure mandates a different management strategy at each life stage. Perturbations to pelagic juveniles will have a diffuse impact on Atlantic nesting colonies, mortality of subadults will have a more focused impact on nearby breeding populations, and disturbances to adults will have pinpoint impact on corresponding breeding populations. These findings demonstrate that surveys of multiple life stages are desirable to resolve management units in migratory marine species. [source] | |||||||||||||