三峡库区场地建筑安全评价研究

三峡水库自 2 0 0 3年蓄水后 ,水对斜坡 (滑坡 )的软化作用和库岸再造大大改变了库区的工程地质条件 ,库区的地质灾害严重制约了库区移民迁镇工程 ,场地建筑安全评价显得尤为重要。笔者根据库区工程地质的特点 ,提出了场地建筑适宜性评价的指标体系 ,建立了场地建筑安全评价人工神经网络模型。通过对红石包滑坡进行各种工况下的稳定性评价 ,利用稳态坡形、坡角工程地质类比法对红石包进行库岸再造的预测 ,对三峡库区巴东县新城区红石包油库建筑进行安全评价。为库区移民迁镇工作提供科学依据。     

Development of synthetic criteria for the ecological evaluation of woodlots and woodlot units

Different criteria have been proposed for the rapid ecological evaluation of wooded areas. It is difficult, however, to determine the criteria most likely to yield results similar to those that would be obtained through detailed surveys and exhaustive evaluation. In order to identify such synthetic criteria, data from a detailed evaluation of Montreal Urban Community woodlots were studied with the help of multivariate analysis. This detailed evaluation was undertaken at two levels—woodlot unit and the woodlots themselves—using 16 different criteria.At the woodlot unit level, area and abundance indices of shade intolerant species in the tree layer could be used as synthetic criteria, while at the woodlot level the ecological value of the constituent units stand out as the first synthetic criterion. These results are compared with criteria proposed in the literature, and the use of multivariate analysis in ecological evaluation is briefly discussed.     

Does taxation alter exploration? : The effect of uncertainty and risk

The effect of resource rent taxation on mineral exploration is a controversial issue on which very little research has been carried out. Simple numerical examples are used in this paper to demonstrate that a ‘pure’ resource rent tax, or Brown Tax, can reduce the extent of exploration of a ‘promising’ deposit by a risk averse explorer, but encourage exploration of ‘unpromising’ deposits. This counter-intuitive result is explained in terms of the effect of the tax and of exploration on the costs of risk and uncertainty.     

煤层气勘探开发中的水污染分析及防治对策

煤层气勘探开发过程的三个阶段(勘探阶段、试生产阶段、和开采阶段)除了都产生生活污水外,勘探阶段的废水污染源主要是钻探过程中排出含有钻井液的废水,试生产阶段的废水污染源主要是含有含11大类20余种化学物质化学成分较复杂的压裂液,开采阶段的废水污染源特征主要是产生大量高矿化度、高盐度的采出水。勘探作业完成后钻井泥浆固化并经过无害化处理后,就地掩埋、清理现场后或复垦或绿化,压裂液废水由于成分复杂,必须处理达标后进行排放,对煤层气采出水经除盐装置处理达标后排放到纳水体中。并对煤层气勘探开发的环境保护具有一定意义。     

Persistence and developmental transition of wide seismic lines in the western Boreal Plains of Canada

This study examined the fate of seismic lines utilized in oil and gas exploration in Canada's western Boreal Plains. It retrospectively followed the persistence, recovery and developmental transition of seismic lines established between the 1960s and the mid-1970s through to 2003. We examined lines that passed through three forest types; aspen, white spruce, and lowland black spruce. In general, the recovery rates of seismic lines to woody vegetation were low. After 35 years, 8.2% of seismic lines across all forest types had recovered to greater than 50% cover of woody vegetation. Only the upland forest types recovered; aspen and white spruce. Most seismic lines ( approximately 65% at 35 years) remained in a cleared state with a cover of low forbs. The most common transition for seismic lines was to tracked access ( approximately 20% at 35 years). Transition to other anthropogenic developments such as roads, pipelines, buildings, and timber harvest blocks was 5% after 35 years. The pulse of industrial activity initiated in the mid-1990s greatly increased the transition rate of seismic to tracked access for a short period of time. The discussion focused on natural and anthropogenic factors that hinder recovery and on the management directions that would facilitate greater recovery rates.     

南海北部海域油气勘探保障建设选址适宜性研究

为分析南海北部海域油气勘探保障建设选址的适宜性,在广泛研究备选区特征资料的基础上,基于层次分析法(Analytic Hierarchy Process, AHP)原理,以自然环境因素、开发环境因素、基础设施与投资情况以及其他因素作为一级评判准则,建立了包括12项二级评判准则的递进层次结构模型,并以永兴岛、赵述岛和晋卿岛作为3个假定备选区,来验证分析评价模型的有效性和可靠性。AHP评判结果显示,3个备选区的整体优劣指数依次为0.587 1, 0.212 1, 0.200 8;AHP模型的一致性比例CR值为0.020 3。通过分析和筛选影响远海油气勘探保障建设的选址因子,构建基于AHP原理的选址评价模型,可用于分析评价南海北部岛礁油气勘探保障建设选址的适宜性。     

初探场地土壤及地下水调查采样方法

随着我国环境保护力度的不断加大,环境调查工作正在有序的开展,其中场地土壤、地下水污染是环境调查的重点,而科学的调查采样方法则是确保调查结果准确性、客观性的必然要求。有鉴于此,首先从污染场地特征分析、调查目标两个角度介绍了场地环境调查的准备工作,然后探讨了布点中的前期准备以及具体方法,最后围绕土壤样品以及地下水样品的采集与保存做了分析。     

环境监理在龙岗气田的实践与探索

文章简要介绍了龙岗气田试采工程特点、环境保护要求及过程管理的难度,以及开展环境监理工作的必要性和重要性。重点总结了龙岗气田工程环境监理工作开展过程中,在前期准备、人员组织、资源配置、目标实现、现场实施、成果体现等方面所做的探索与实践,对今后大型油气地面工程建设开展环境监理工作具有一定的借鉴意义和参考作用。     

Concentrations of (137)Cs in summer pasture plants that reindeer feed on in the reindeer management area of Finland

Samples of summer pasture plants that reindeer feed on were collected in order to study ¹³⁷Cs concentrations in different plant species and in species nested in certain site types, and to study the regional distribution of ¹³⁷Cs in the Finnish reindeer management area. Plant species were categorized by the site types of mineral soil forest (xeric heath forest and mesic heath forest) and peatland. A third category called ’other plant species’ included plants with various site types, poorly determined species and species with poor statistics. The ¹³⁷Cs concentrations in different site types differed significantly. The mean ¹³⁷Cs concentrations of the whole reindeer management area in the xeric heath forest plant species was 44 ± 27 Bq/kg dw, in the mesic heath forest plant species 75 ± 59 Bq/kg dw and in the peatland plant species 219 ± 150 Bq/kg dw. The peatland species uptake ¹³⁷Cs more efficiently than plant species of mineral soil forests. A particularly efficient collector of ¹³⁷Cs was Trichophorum sp. It is suggested that Trichophorum sp. could be used as an indicator species for reindeer summer fodder plants. The highest concentrations of ¹³⁷Cs were found in Southern Lapland and the lowest in Northern Lapland. Today, the concentrations of ¹³⁷Cs in summer pasture plants that reindeer feed on in Finland are at such a level that there is no need to avoid any plant species. In the case of future nuclear fallout, reindeer grazing in peatlands would increase concentrations of ¹³⁷Cs in reindeer meat.     

Seasonal variation of organochlorine contaminants in bonito (Sarda sarda L. 1758) and anchovy (Engraulis encrasicolus L. 1758) in Black Sea region, Turkey

The concentrations of indicator polychlorinated biphenyls (PCBs) and organochlorine insecticides were determined in bonito (Sardasarda L. 1758) and anchovy (Engraulisencrasicolus L. 1758) from the Black Sea, Turkey. Concentrations of total indicator PCBs ranged between <1-17.0 in bonito, and <1-17.5 ng/g fresh weight in anchovy, and total of 1,1,1-trichloro-2,2-bis-chlorophenyl-ethane and its metabolites’ (DDTs) concentrations ranged between 13.4-26.3, and 2.96-19.0 ng/g fresh weight in bonito and anchovy respectively. PCB 52, p,p′-DDE and endosulfan (α + β) were found dominant in both of the fish species. Except endosulfan, and some DDT metabolites, none of the studied organochlorine pesticides was detected in the fish samples. Concentrations of PCBs in anchovy were found higher than those in bonito, whereas DDT and endosulfan concentrations were found similar in both of the fish species. All of the fish samples had residue concentrations below the maximum residue limits (MRL) recommended by FAO/WHO Codex Alimentarius Commission.