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81.
应对不确定性:呼吁建立新的科学政策论坛   总被引:4,自引:1,他引:4  
科学界和政策界具有不同的目标,这就自然导致了对构成某种变化或现象的"检验"标准的差异,以及用不同的方法去描述不确定性和风险的持性及传达不确定性和风险.这些差异可能损害科学家、决策者和公众之间的有效沟通,同时也限制了科学家所愿意研究的社会紧迫问题的类型.本文主要回顾了一系列处理不确定性问题的方法,阐述了当科学和政策不能很好协调时所可能引起的一些错误.并在此基础上,特别针对解决不确定性问题提出了一些具体建议,包括重构科学规范,建立由科学、政策两方面领导广泛参加的科学政策论坛.  相似文献   
82.
Synthetic fibers as an indicator of land application of sludge   总被引:6,自引:0,他引:6  
Synthetic fabric fibers have been proposed as indicators of past spreading of wastewater sludge. Synthetic fiber detectability was examined in sludges (dewatered, pelletized, composted, alkaline-stabilized) and in soils from experimental columns and field sites applied with those sludge products. Fibers (isolated by water extraction and examined using polarized light microscopy) were detectable in sludge products and in soil columns over 5 years after application, retaining characteristics observed in the applied sludge. Concentrations mirrored (within a factor of 2) predictions based on soil dilution. Fibers were detectable in field site soils up to 15 years after application, again retaining the characteristics seen in sludge products. Concentrations correlated with residual sludge metal concentration gradients in a well-characterized field site. Fibers found along preferential flow paths and/or in horizons largely below the mixed layer suggest some potential for translocation. Synthetic fibers were shown to be rapid and semi-quantitative indicators of past sludge application.  相似文献   
83.
Kay P  Blackwell PA  Boxall AB 《Chemosphere》2005,60(4):497-507
The environment may be exposed to veterinary medicines administered to livestock due to the application of organic fertilisers to land. For other groups of substances that are applied to agricultural land (e.g. pesticides), preferential flow in underdrained clay soils has been identified as an extremely important pathway by which pollution of surface waters can occur. Three soil column leaching experiments have therefore been carried out using a clay soil to investigate the fate of a range of antibiotics from the sulphonamide, tetracycline and macrolide groups. These column studies complemented a range of other experiments at the field and semi-field scales, as well as modelling studies which are being reported in separate papers. Each column study had a different objective. The first examined the effect of pig slurry on the mobility of antibiotics in clay loam soil. The second experiment investigated changes in soil water pH due to the application of slurry. The final experiment quantified the extent to which soil tillage prior to slurry application can reduce the leaching of antibiotic residues found in slurry. It was found that slurry had no impact on the leaching of oxytetracycline although soil water pH was affected significantly by slurry application. It was also shown that pre-tillage can substantially reduce the leaching of antibiotic residues through macroporous clay soils.  相似文献   
84.
Persistence of carbofuran in marine sand and water   总被引:4,自引:0,他引:4  
Campbell S  David MD  Woodward LA  Li QX 《Chemosphere》2004,54(8):1155-1161
Marine sand and seawater samples were collected in March 2002 from Laysan Island in the Hawaiian Islands National Wildlife Refuge, where a small area was contaminated by the carbamate insecticide carbofuran. Carbofuran was still detected at microg g(-1) levels in the Laysan sand after its identification in 1998 and initial observation of the toxicity in 1988. The persistence of carbofuran in the marine sand was investigated in the dark in a 30 degrees C oven, and in distilled deionized water and seawater samples exposed to artificial 300 nm light and to direct sunlight. The laboratory study showed a half-life (t1/2) of approximately 40 days for carbofuran in the native sand and in Ottawa sand. The photolysis of carbofuran was faster in seawater than in distilled deionized water when it was exposed to 300 nm light (t1/2, 0.1 vs. 3.1 h) and to direct sunlight (t1/2, 7.5 vs. 41.6 h). The large difference between the laboratory results and the field observation of carbofuran dissipation suggests that carbofuran degradation at the remote, undisturbed marine site may be governed by its unique environmental factors.  相似文献   
85.
The scientific and policy worlds have different goals, which can lead to different standards for what constitutes "proof" of a change or phenomena, and different approaches for characterizing and conveying uncertainty and risk. These differences can compromise effective communication among scientists, policymakers, and the public, and constrain the types of socially compelling questions scientists are willing to address. In this paper, we review a set of approaches for dealing with uncertainty, and illustrate some of the errors that arise when science and policy fail to coordinate correctly. We offer a set of recommendations, including restructuring of science curricula and establishment of science-policy forums populated by leaders in both arenas, and specifically constituted to address problems of uncertainty.  相似文献   
86.
Summary The social behavior of house mice captured from natural populations was studied in an enclosure. Six replicate experiments with observations totalling 344 h were done to contrast the behavior of outbreeders, individuals that have progeny by interdemic reproduction; inbreeders, individuals that have progeny by intrademic reproduction; and nonbreeders. The frequency of outbreeding was also determined.In each replicate, two male and three female commensal house mice, Mus musculus, homozygous for the same allele at the hemoglobin locus, Hbb s , were put in half of a population cage. A barrier separated this deme from another deme homozygous for the alternative allele, Hbbd. The barrier was removed after a month and each experiment continued for a further two months with daily observations.In five of six experiments, the mice from both demes formed one social group and in the sixth experiment, the mice remained in their original demes. In two experiments, outbreeding occurred: females from one deme produced offspring by males from the other deme. In three experiments, inbreeding occurred: females produced offspring by males from the same deme. Soon after the demes had formed one social group in these three experiments, the remaining male in a deme was killed and the experiment terminated; females without a male readily join other demes. The pattern of breeding resulted in a genetically effective size, N e , that was approximately half of the maximum N e obtainable with random mating. The social organization of house mice, although structured and characterized by male territoriality, presents no major barrier to gene flow within populations.Affiliative (mount, allogroom, follow) and agonistic (fight, chase, attack) behavior occurring when the barrier was present had no predictive value in determining which mice would be outbreeders. With the barrier absent, outbreeders were the recipients of more affiliative behavior than inbreeders. Male outbreeders initiated more agonistic behavior than inbreeders. Outbreeders engaged in more interdemic affiliative behavior than inbreeders.Contribution no. 362 from the Department of Ecology and Evolution at SUNY, Stony Brook  相似文献   
87.
We report three cases of Turner's syndrome with cystic hygromata, which were diagnosed by routine ultrasound scanning before amniocentesis in the second trimester of pregnancy. Maternal and amniotic level of alpha-fetoprotein were normal. Karyotyping carried out afterwards showed a 45,X karyotype. Our data indicate, that cystic hygromata in Turner's syndrome may coexist with a normal amniotic fluid AFP, thus questioning the theory of leakage from the hygroma. It remains to be investigated if all cases of Turner's syndrome present a cystic hygroma in utero.  相似文献   
88.
In order to examine the condition of biota in Atlantic coast estuaries, "Contaminant Exposure and Effects—Terrestrial Vertebrates" database (CEE-TV) has been compiled through computerized search of published literature, review of existing databases, and solicitation of unpublished reports from conservation agencies, private groups, and universities. Summary information has been entered into the database, including species, collection date (1965–present), site coordinates, estuary name, hydrologic unit code, sample matrix, contaminant concentrations, biomarker and bioindicator responses, and reference source, utilizing a 98-field character and numeric format. Currently, the CEE-TV database contains 3699 geo-referenced records representing 190 vertebrate species and >140,000 individuals residing in estuaries from Maine through Florida. This relational database can be directly queried or imported into a Geographic Information System to examine spatial patterns, identify data gaps and areas of concern, generate hypotheses, and focus ecotoxicological field assessments. Information on birds made up the vast majority (83%) of the database, with only a modicum of data on amphibians (<0.1%). Of the >75,000 chemical compounds in commerce, only 118 commonly measured environmental contaminants were quantified in tissues of terrestrial vertebrates. There were no CEE-TV data records in 15 of the 67 estuaries located along the Atlantic coast and Florida Gulf coast. The CEE-TV database has a number of potential applications including focusing biomonitoring efforts to generate critically needed ecotoxicological data in the numerous "gaps" along the coast, reducing uncertainty about contaminant risk, identifying areas for mitigation, restoration or special management, and ranking ecological conditions of estuaries.  相似文献   
89.
Mainstreaming climate change adaptation (CCA) into plans and programs is still a new approach in adaptation and thus there is limited information on how to operationalize it on-ground. This paper addresses this gap by investigating the challenges in mainstreaming CCA into the local land use plans in the province of Albay, Philippines. Specifically, this paper developed 20 quantitative “mainstreaming indicators” to assess the state-of-play and the challenges for local mainstreaming. These indicators were classified under three groupings, namely, the information, institutional, and resource capacities of systems. Qualitative analysis of the indicator scores suggested that developing the institutional capacities of local governments is crucial in the local mainstreaming process. Likewise, the results highlighted the “institutional issues” indicator as the primary barrier in operationalizing the approach. These institutional issues are: fragmented laws and regulations; overlapping policy requirements; and the lack of guidelines for mainstreaming CCA into the local land use plans. Meanwhile, the “leadership” indicator, as signified by a climate change champion in Albay, was evaluated as an opportunity for local mainstreaming. The champion effectively led the CCA efforts because the existing institutional mechanisms supported the champion’s capacity to influence the behavior of people and produce collective action towards CCA.  相似文献   
90.
Social structure emerges from the patterning of interactions between individuals and plays a critical role in shaping some of the main characteristics of animal populations. The topological features of social structure, such as the extent to which individuals interact in clusters, can influence many biologically important factors, including the persistence of cooperation, and the rate of spread of disease. Yet, the extent to which social structure topology fluctuates over relatively short periods of time in relation to social, demographic, or environmental events remains unclear. Here, we use social network analysis to examine seasonal changes in the topology of social structures that emerge from socio-positive associations in adult female rhesus macaques (Macaca mulatta). Behavioral data for two different association types (grooming and spatial proximity) were collected for females in two free-ranging groups during two seasons: the mating and birth seasons. Stronger dyadic bonds resulted in social structures that were more tightly connected (i.e., of greater density) in the mating season compared to the birth season. Social structures were also more centralized around a subset of individuals and more clustered in the mating season than those in the birth season, although the latter differences were mostly driven by differences in density alone. Our results suggest a degree of temporal variation in the topological features of social structure in this population. Such variation may feed back on interactions, hence affecting the behaviors of individuals, and may therefore be important to take into account in studies of animal behavior.  相似文献   
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