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651.
652.
开封市公园灰尘重金属含量及潜在生态风险 总被引:3,自引:0,他引:3
采集河南省开封市区4个典型公园(清明上河园、龙亭公园、铁塔公园、相国寺)52个地表灰尘样品,采用原子荧光(AFS)法、电感耦合等离子体发射光谱法(ICP)和电感耦合等离子体质谱(ICP-MS)法测定灰尘重金属含量,并用调整后的Hkanson潜在生态危害分级标准对重金属潜在生态危害进行评价。结果表明:灰尘Cd、Hg、Pb、Zn、Cu富集显著。重金属单项生态风险指数(E)顺序为HgCdPbCuNiZnCoCrMnTi,除Hg和Cd出现强烈以上生态风险外,其他重金属风险轻微。所有公园灰尘重金属潜在生态总风险(RI)均在很强等级以上,其大小依次为RI相国寺RI龙亭公园RI铁塔公园RI清明上河园。灰尘Hg和Cd对RI的平均贡献率分别为45.28%和46.77%,是最主要的风险因子。 相似文献
653.
654.
采用非均相催化臭氧氧化工艺深度处理化工废水二级生化出水,探索负载不同活性组分的活性炭催化剂及该工艺处理化工废水的影响因素。结果表明:当进水COD为85~110 mg/L,臭氧投加量为60 mg/L,催化剂投加量为200 mg/L Cr时,臭氧氧化、ACCA-1、ACCA-2和ACCA-3催化臭氧氧化对出水COD的平均去除率分别为22.46%、32.7%、40.5%和35.7%,3种催化剂均可强化臭氧氧化效果。活性炭催化剂能提高臭氧利用率,叔丁醇对ACCA-2抑制效果最明显。 相似文献
655.
采用自身对照试验,利用个体噪声剂量系统检测海洋石油钻井平台作业人员在作业期间生产性噪声个体暴露水平(40 h等效声级),采用酶联免疫吸附试验(ELISA)分别检测噪声暴露作业前后血清皮质醇水平,并分析血清皮质醇水平变化与噪声暴露水平和暴露时间的关系。结果表明:噪声暴露作业后,全部作业人员血清皮质醇水平明显升高(p0.05,α=0.05);不同噪声暴露水平作业人员血清皮质醇水平差别没有统计学意义(p0.05);噪声暴露20 d的作业人员血清皮质醇水平明显高于噪声暴露≤20 d者(p0.05)。血清皮质醇水平变化与噪声暴露水平没有显著关联性,而与噪声暴露时间呈明显的正相关(p0.05)。研究表明,生产性噪声慢性暴露使血清皮质醇水平升高,且暴露时间是主要影响因素。 相似文献
656.
Aleksander Astel Vasil Simeonov Hans Puxbaum 《Environmental pollution (Barking, Essex : 1987)》2010,158(10):3201-3208
The present study deals with the application of N-way factor analysis for modeling and interpretation of a three-dimensional environmental data set acquired from monitoring of particulate matter (PM) collected at four different sampling locations in Lower Austria region (Central Europe). In the study the Tucker3 algorithm for N-way modeling was used. It was statistically validated that the Tucker3 model offered having the dimensionality [222] is appropriate for correct interpretation of the relationships between chemical parameters, sampling locations and sampling period. The Tucker3 model allowed to distinguish three major sources of pollution in the region of interest conditionally named “soil dust”, “combustion” and “street dust” latent factors as responsible for chemical profile of PM and to identify seasonal variability. Additionally, some specificity of the sampling locations was also pointed out. 相似文献
657.
Eva S. Stangler Stefan Jarau Michael Hrncir Ronaldo Zucchi Manfred Ayasse 《Chemoecology》2009,19(1):13-19
Foragers of several species of stingless bees deposit pheromone spots in the vegetation to guide recruited nestmates to a
rich food source. Recent studies have shown that Trigona and Scaptotrigona workers secrete these pheromones from their labial glands. An earlier report stated that species within the genus Geotrigona use citral from their mandibular glands for scent marking. Since convincing experimental proof for this conjecture is lacking,
we studied the glandular origin of the trail pheromone of Geotrigona mombuca. In field bioassays, newly recruited bees were diverted by artificial scent trails that branched off from the natural scent
trail deposited by their nestmates only when they were baited with extracts from the foragers’ labial glands. Compounds extracted
from the mandibular glands, however, did not release trail following behavior. This demonstrates that the trail pheromone
of G. mombuca is produced in the labial glands, as in Trigona and Scaptotrigona. Furthermore, in chemical analyses citral was identified exclusively in the foragers’ mandibular glands, which disproves
its supposed role as a trail pheromone. The labial glands contained a series of terpene- and wax type esters, with farnesyl
butanoate as major constituent. We, therefore, postulate that the trail pheromone of G. mombuca is composed of a blend of esters. 相似文献
658.
Protected areas’ chief conservation objectives are to include species within their boundaries and protect them from negative external pressures. Many protected areas are not achieving these goals, perhaps in part due to land development inside and outside protected areas. We conducted spatial analyses to evaluate the ability of Canadian protected areas to mitigate the effects of nearby land development. We investigated correlations of national patterns of land development in and around protected areas and then examined national patterns of roads, urban area, and croplands in protected areas. We calculated the amount of developed land in protected areas and within 25–100 km of protected‐area borders, the density of roads, and extent of urban and cropland area in protected areas. We constructed logistic‐regression models to test whether development in a protected area was associated with landscape and protected‐area characteristics. Land development was far less extensive inside than outside protected areas. However, several protected areas, particularly small southern areas near small urban centers had substantial development inside their boundaries, and nearly half of protected areas had roads. The cumulative extent of development within 50 km of protected areas was the best predictor of the probability of land development in protected areas. Canadian First Nations, industries, government, and nongovernmental organizations are currently planning an unprecedented number of new protected areas. Careful management of areas beyond protected‐area boundaries may prove critical to meeting their long‐term conservation objectives. Desarrollo de Tierras Dentro y Alrededor de Áreas Protegidas en la Frontera Silvestre 相似文献
659.
With the development of increasingly complex processes and technologies in chemical and manufacturing industries, Process Safety Management (PSM) has been globally recognized as the primary tool for operating companies to reduce process accidents on their industrial sites and the risks posed to their employees and surrounding communities. Yet, industrial facilities are often interdependent and collocated with others. Recognizing this, regional authorities are also applying PSM principles to reduce the cumulative incidents associated with high density industrial areas and the multiplicative risks posed to broader communities. This paper compares Strathcona County Emergency Service (SCES) in Alberta, Contra Costa County Health Service Hazard Material Programs (CCCHSHMP) in California, and Technical Standards & Safety Authority (TSSA) in Ontario and their PSM systems to provide practical recommendations to improve SCES's system. Four aspects of PSM are considered: regulation and guidance, auditing and inspection, annual performance indicators, and public participation. Based on the results of this comparison, we recommend that SCES develop comprehensive PSM regulations based on CSA Z767-17 PSM including clear instructions for assessing technologies and methodologies for consequence analysis. Both worst-case scenarios and alternative scenarios need to be considered as well as the domino effect of primary accidents. Furthermore, regular audits and inspections will ensure compliance with PSM regulations while helping the design of planning, performing, and following-up strategies to ensure effectiveness. In addition, we suggest the use of lagging and leading performance indicators to evaluate the performance of the PSM program. Finally, we recommend using advisory councils or commissions to increase public participation and ensure the representation of stakeholders' perspectives with the PSM system. 相似文献
660.
发展旅游业是扩大就业的重要渠道。森林公园旅游业是中国森林旅游业的主体。本文首先概述了中国森林公园建设与发展状况,并基于林业统计年鉴数据,分析中国森林公园旅游业发展及直接就业效应,进而采用投入产出法对森林公园旅游业的间接就业效应进行了测算,最后总结全文并提出相关政策建议。研究结果表明:森林公园旅游业持续发展的就业效应可观。测算数据显示,2011-2020年森林公园旅游业的总体就业量为512.1万人,其中直接和间接就业量分别为238.5万人和273.6万人。 相似文献