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81.
TSP-PM10-PM2.5-2型中流量大气颗粒物采集系统的开发和应用   总被引:13,自引:0,他引:13  
自行开发并研制了TSP-PM10-PM2.5-2型中流量TSP、PM10、PM2.5大气颗粒物采集系统,是目前中国唯一可以采集TSP、PM10、PM2.5样品并提供足够的样品量进行大气颗粒物化学成分分析的中流量大气颗粒物采集器.该系统精心设计和加工的限流孔可以保持完全固定的流量,保证切割粒径的稳定,减小采样的误差并方便操作.该系统已经成功地应用于20多个城市和地区大气颗粒物的监测和研究中,为研究大气颗粒物的污染状况和来源提供了有效的技术手段和支持.  相似文献   
82.
兰州市功能区大气细菌污染和城市绿地系统杀菌效应分析   总被引:7,自引:1,他引:7  
在测定兰州市城市不同功能区和不同类型绿地系统空气细菌数量的基础上,分析了各功能区空气细菌污染状况,以及人流量和车流量与空气细菌数量之间的关系;探讨了不同绿地系统的杀菌效应,指出各绿地系统杀菌能力:乔、灌、草>乔、灌>草、灌>草坪。  相似文献   
83.
This paper argues on both theoretical and empirical grounds that, beyond a certain point, there is an unavoidable conflictbetween economic development (generally taken to mean 'materialeconomic growth') and environmental protection. Think for a moment of natural forests, grasslands, marine estuaries, salt marshes, and coral reefs; and of arable soils, aquifers, mineraldeposits, petroleum, and coal. These are all forms of 'natural capital' that represent highly-ordered self-producing ecosystemsor rich accumulations of energy/matter with high use potential (low entropy). Now contemplate despoiled landscapes, eroding farmlands, depleted fisheries, anthropogenic greenhouse gases,acid rain, poisonous mine tailings and toxic synthetic compounds.These all represent disordered systems or degraded forms of energy and matter with little use potential (high entropy). The main thing connecting these two states is human economic activity. Ecological economics interprets the environment-economyrelationship in terms of the second law of thermodynamics. The second law sees economic activity as a dissipative process. Fromthis perspective, the production of economic goods andservices invariably requires the consumption of available energy and matter. To grow and develop, the economynecessarily 'feeds' on sources of high-quality energy/matter first produced by nature. This tends to disorder and homogenizethe ecosphere, The ascendance of humankind has consistently been accompanied by an accelerating rate of ecological degradation, particularly biodiversity loss, the simplificationof natural systems and pollution. In short, contemporary political rhetoric to the contrary, the prevailing growth-oriented global development paradigm is fundamentally incompatible with long-term ecological and social sustainability. Unsustainability is not a technical nor economic problem as usually conceived, but rather a state of systemic incompatibilitybetween a economy that is a fully-contained, growing, dependent sub-system of a non-growing ecosphere. Potential solutions fly inthe face of contemporary development trends and cultural values.  相似文献   
84.
环境监测业务管理系统的设计与开发   总被引:1,自引:0,他引:1  
以郑州市环境监测中心站监测业务流程为例,从技术路线、系统结构设计、系统功能分析和技术实现等方面分析并介绍了环境监测业务管理系统的特点和开发时需解决的技术问题。探讨了建立基于B/S结构、J2EE技术架构、创新的组件装配方式、Oracle9i数据库、中间件和多层体系结构等多项先进技术进行系统实现的设计方案。  相似文献   
85.
The potential ecological risks associated with contaminants from 15 abandoned shrimp ponds in southern Thailand were assessed at the screening level. Shrimp ponds reported as out of production for more than 2 years were selected as sampling sites. The assessment endpoint was identified as the protection of aquatic life from hazard of multiple agents or stressors in water or sediment from the ponds. The measurement endpoints were amount of toxic phytoplankton species, Yellow Head Viruses, SEMB viruses, oxytetracycline, cadmium, copper, and manganese. Data from field measurements and laboratory analyses obtained primarily from April to June 2003 were used in the risk analysis. The results showed that insignificant amounts of stressors were present, except for the metals. So, only concentration values of the metals were used in the calculation of hazard quotients (HQ) for risk characterization. The highest potential ecological risk characterized by the highest HQ value observed for each metal was 19 for manganese, 4.3 for cadmium, and 1.8 for copper. These findings indicated a need for further ecological risk assessment at a more detailed level to focus on the bioavailability and effects of metals from abandoned shrimp farms, with manganese the highest priority.  相似文献   
86.
Environmental benchmarks are widely used in Canadian environmental assessment as a standard against which to monitor air or water quality in response to human activities in the environment. Recent work in Canada has developed the concept of ecological benchmarks as a complement to environmental benchmarks. However, implementation of ecological benchmarks may be challenging. This paper presents an analogy between ecological benchmarks and the more commonly used environmental benchmarks, as an attempt to increase understanding and use of ecological benchmarks in resource management, assessment, and monitoring. Ecological benchmarks, and their corresponding indicators, will be challenging to identify and use. However, through the use of the principles of adaptive management, effective ecological indicators and benchmarks can be established. Although it is essential that ecological benchmarks are site-specific, the analogy and general principles outlined here are applicable to assessment and monitoring in any part of the world.  相似文献   
87.
用灰色聚类法对荔湾湖水质富营养化程度的评价   总被引:37,自引:2,他引:37  
灰色聚类法把湖泊系统当作一个灰色系统来研究,将灰色聚类理论应用于湖泊富营养化程度的评价中,以广州市荔湾湖为例,建立不同的聚类指标所拥有的隶属函数,确定聚类权重值,求得最大聚类系数及聚类结果,得出用灰色聚类法进行湖泊水质富营养化评价,既能体现水质等级界线的模糊性,又能充分利用信息,避免了模糊数学法的不合理之处。因而,灰色聚类法是一种简便、客观、可靠的方法。  相似文献   
88.
土壤重金属污染的灰色模糊评价   总被引:14,自引:1,他引:14  
以灰色聚类为基础,提出了灰色模糊聚类分析法,并将其应用于土壤环境质量评价中,经实例分析表明,这是一种较为简便,合理、有效的评价方法。  相似文献   
89.
基于B-P神经网络的环境质量评价方法   总被引:3,自引:0,他引:3  
提出可将环境质量评价的无论是定量指标还是定性参数转化成"二进制"的"1"或"0",进而将这种二进制数引入B-P网络.通过实例探讨,这种新的B-P网络既适用于定量指标的水质参数又适用于定性指标的水质参数.  相似文献   
90.
We evaluate a field method for determining species richness andcanopy cover of vascular plants for the Forest Health MonitoringProgram (FHM), an ecological survey of U.S. forests. Measurementsare taken within 12 1-m2 quadrats on 1/15 ha plots in FHM.Species richness and cover are determined for four height classes(strata) within each quadrat and aggregated by stratum over the entireplot. We estimated (1) the agreement between experienced trainers andinexperienced technicians who collected the data on this survey(accuracy) and (2) the agreement among the technicians (precision) forresults on species richness and cover from 3 test plots at 3 timeintervals. The methods appear to be highly precise, although somediscrepancies with the values obtained by the trainers were found.Trainers found significantly more species in the ground stratum (0–0.6 m) and measured significantly more cover in the uppermost stratum(>4.9 m). The proportion of variation due to measurement error andtemporal variability was less than 13% for species richness (all strata)and cover (all but one stratum). This indicates that the method issuitable for monitoring changes in species richness and canopy coverfor a large-scale synoptic monitoring project such as FHM.  相似文献   
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