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91.
环境思考还没有被大多数商业关注看做是主流业务问题.  相似文献   
92.
The fates of two compounds, 2,4 Dichlorophenoxy Acetic Acid Butoxyethyl Ester (2,4-DBEE) and 1,4 Dichlorobenzene (1,4-DCB), were examined in in situ microcosms placed in a pond and compared with the fates in the pond itself. Results also were compared with predictions of an aquatic fate and transport model (EXAMS). Decay rates of 2,4-DBEE were not significantly different among the microcosms, pond and model predictions. The decay rate of 1,4-DCB in the microcosms was significantly lower than the rate for the pond, and lower than the rate predicted by the model. The low volatility of 1,4-DCB in the microcosms is attributed primarily to lack of water surface turbulence in the microcosms.  相似文献   
93.
94.
The development and effective introduction of strategies designed to ensure the ecologically and economically sustainable utilization of coastal and marine resources is perhaps the major challenge for Small Island Developing States (SIDS). In response, the 1994 Barbados Programme of Action (BPoA) called upon the SIDS to implement appropriate coastal and marine strategies and, crucially, ensure that such strategies were integrated into sustainable national development plans (NDPs). This article examines the extent to which contemporary NDPs and donor support programmes have incorporated the fisheries sector — arguably the most important coastal/marine resource for many SIDS — into such documents. Applying an assessment methodology, originally developed to identify levels of environmental mainstreaming within World Bank country assistance strategies to NDPs and donor support programmes, we are able to identify those SIDS who have most effectively integrated the fisheries sector into such documents. Comparison with data indicating the importance of the sector to the national economy (in terms of generating foreign exchange, employment generation and/or supporting domestic protein consumption levels) enables us to pinpoint those countries with substantial fisheries sectors, but a correspondingly lower than expected degree of sectoral mainstreaming. We suggest that the January 2005 review of the BPoA offers an opportune moment for such countries to redress these omissions.  相似文献   
95.
Adaptation to climate change has been reviewed in several developed nations, but in none where consideration of the effects of climate change is required by statute and devolved to local government. We examine the role of institutional arrangements, the players operating under them, the barriers and enablers for adaptation decision-making in the developed nation of New Zealand. We examine how the roles and responsibilities between national, regional and local governments influence the ability of local government to deliver long-term flexible responses to changing climate risk. We found that the disciplinary practices of law, engineering and planning, within legal frameworks, result in the use of static mechanisms which create inflexible responses to changing risk. Several enablers are identified that could create greater integration between the different scales of government, including better use of national policy instruments, shared professional experience, standardised information collection and risk assessment methods that address uncertainties. The framing of climate risk as dynamic and changing that differentiates activities over their lifetime, development of mechanisms to fund transitions towards transformational change, are identified as necessary conditions for delivering flexible responses over time.  相似文献   
96.
Schultz C  Grundl T 《Chemosphere》2004,57(10):1301-1306
This work examines the abilities of two smectite minerals (SWa-1 and Wyoming montmorillonite) to adsorb ferrous iron at concentrations from 0.037 mM (2 ppm) to 2.5 mM (240 ppm) over a range of pHs from 4.0 to 8.0. Both sorption isotherm and sorption edge data are presented. Ferrous sorption (Fe(aq)2+ = 0.1 mM) to both SWa-1 and Wyoming montmorillonite over the pH range 4.0-6.75 is relatively constant at approximately 1000 l kg(-1) for both minerals. Sorption in this pH range is attributed to the cation exchange capacity of the clay along the basal surfaces. At pH values above 6.75 the amount of ferrous iron sorbed increases dramatically. At pH 8, sorption (Fe(aq)+ = 0.1 mM) reaches 6600 l kg(-1) and 8000 l kg(-1) for Swa-1 and Wyoming montmorillonite respectively. This is attributed to the specific interaction between ferrous ions and surface sites along mineral edges. The overriding geochemical implication is that in reduced sediments containing more than a few percent clay, the pool of sorbed ferrous iron is vast. This pool of reduced iron is both redox labile and bio-available and is not readily indicated by simple measurement of dissolved Fe2+.  相似文献   
97.
Ng TY  Pais NM  Dhaliwal T  Wood CM 《Chemosphere》2012,87(11):1208-1214
We tested the use of whole-body and subcellular Cu residues (biologically-active (BAM) and inactive compartments (BIM)), of the oligochaete Lumbriculus variegatus to predict Cu toxicity in fresh water. The critical whole-body residue associated with 50% mortality (CBR50) was constant (38.2-55.6 μg g−1 fresh wt.) across water hardness (38-117 mg L−1 as CaCO3) and exposure times during the chronic exposure. The critical subcellular residue (CSR50) in metal-rich granules (part of BIM) associated with 50% mortality was approximately 5 μg g−1 fresh wt., indicating that Cu bioavailability is correlated with toxicity:subcellular residue is a better predictor of Cu toxicity than whole-body residue. There was a strong correlation between the whole-body residue of L. variegatus (biomonitor) and survival of Chironomus riparius (relatively sensitive species) in a hard water Cu co-exposure. The CBR50 in L. variegatus for predicting mortality of C. riparius was 29.1-45.7 μg g−1 fresh wt., which was consistent within the experimental period; therefore use of Cu residue in an accumulator species to predict bioavailability of Cu to a sensitive species is a promising approach.  相似文献   
98.
In the Cape honey bee Apis mellifera capensis, workers lay female eggs without mating by thelytokous parthenogenesis. As a result, workers are as related to worker-laid eggs as they are to queen-laid eggs and therefore worker policing is expected to be lower, or even absent. This was tested by transferring worker- and queen-laid eggs into three queenright A. m. capensis discriminator colonies and monitoring their removal. Our results show that worker policing is variable in A. m. capensis and that in one colony worker-laid eggs were not removed. This is the first report of a non-policing queenright honey bee colony. DNA microsatellite and morphometric analysis suggests that the racial composition of the three discriminator colonies was different. The variation in policing rates could be explained by differences in degrees of hybridisation between A. m. capensis and A. m. scutellata, although a larger survey is needed to confirm this.  相似文献   
99.
A new spatially balanced sampling design for environmental surveys is introduced, called Halton iterative partitioning (HIP). The design draws sample locations that are well spread over the study area. Spatially balanced designs are known to be efficient when surveying natural resources because nearby locations tend to be similar. The HIP design uses structural properties of the Halton sequence to partition a resource into nested boxes. Sample locations are then drawn from specific boxes in the partition to ensure spatial diversity. The method is conceptually simple and computationally efficient, draws spatially balanced samples in two or more dimensions and uses standard design-based estimators. Furthermore, HIP samples have an implicit ordering that can be used to define spatially balanced over-samples. This feature is particularly useful when sampling natural resources because we can dynamically add spatially balanced units from the over-sample to the sample as non-target or inaccessible units are discovered. We use several populations to show that HIP sampling draws spatially balanced samples and gives precise estimates of population totals.  相似文献   
100.
在线富集HTLC/MS/MS分析环境水资源中多种抗生素   总被引:2,自引:0,他引:2  
<正>人们日益关注环境水资源中抗生素的存在情况.这迫使环境和政府实验室开发新的液相色谱/质谱(LC/MS)方法,以监测水资源中抗生素的存在状况.然而,环境水资源中含有的抗生素通常是很痕量的,往往需要大量的水样进行富集和净化.在液相色谱/质谱(LC/MS)分析之前,需要对大约100—1000ml水样进行富集和清理,以达到被测物质的检测限。  相似文献   
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