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781.
2008年北京市大气质量的灰色预测 总被引:7,自引:0,他引:7
运用灰色关联分析方法对北京市大气主要污染物质进行了分析,得出PM10、TSP和SO2是主要污染因子。在此基础上,运用灰色系统理论建模方法,分别建立主要污染因子的预测模型。运用该模型预测出到2008年北京市的TSP和PM10仍不能达到国家二级标准。在今后几年内降低颗粒物的污染是北京市大气污染控制工作的首要任务。 相似文献
782.
PPCPs在不同营养级水生生物体内的累积与代谢 总被引:1,自引:0,他引:1
在总结药品及个人护理品(PPCPs)在水环境中分布特征的基础上,分析和对比了典型PPCPs在不同营养级水生生物(浮游植物、底栖生物和鱼类)体内的累积规律,并阐述了PPCPs在鱼体内的代谢转化途径和机理.提出未来该领域的主要研究方向包括加强对个人护理品生物累积和食物链传递的研究,深入探索PPCPs在食物链上的传递和累积规律,开展实际水体中PPCPs的代谢转化研究. 相似文献
783.
Wayland M Headley JV Peru KM Crosley R Brownlee BG 《Environmental monitoring and assessment》2008,136(1-3):167-182
An immense volume of tailings and tailings water is accumulating in tailings ponds located on mine leases in the oil sands
area of Alberta, Canada. Oil sands mining companies have proposed to use tailings- and tailings water-amended lakes and wetlands
as part of their mine remediation plans. Polycyclic aromatic hydrocarbons (PAHs) are substances of concern in oil sands tailings
and tailings water. In this study, we determined concentrations of PAHs in sediments, insect larvae and adult insects collected
in or adjacent to three groups of wetlands: experimental wetlands to which tailings or tailings water had been purposely added,
oil sands wetlands that were located on the mine leases but which had not been experimentally manipulated and reference wetlands
located near the mine leases. Alkylated PAHs dominated the PAH profile in all types of samples in the three categories of
wetlands. Median and maximum PAH concentrations, especially alkylated PAH concentrations, tended to be higher in sediments
and insect larvae in experimental wetlands than in the other types of wetlands. Such was not the case for adult insects, which
contained higher than expected levels of PAHs in the three types of ponds. Overlap in PAH concentrations in larvae among pond
types suggests that any increase in PAH levels resulting from the addition of tailings and tailings water to wetlands would
be modest. Biota-sediment accumulation factors were higher for alkylated PAHs than for their parent counterparts and were
lower in experimental wetlands than in oil sands and reference wetlands. Research is needed to examine factors that affect
the bioavailability of PAHs in oil sands tailings- or tailings water-amended wetlands. 相似文献
784.
基于GIS的珠三角区域空气质量实况发布平台介绍 总被引:2,自引:1,他引:1
地理信息系统是在计算机软件和硬件支持下,对整个或者部分地球表层空间中的各类地理信息数据进行采集、存储、管理、运算、分析、显示和描述的技术系统。根据中国发布的环境空气质量新标准,提出了基于地理信息系统的区域空气质量实况发布平台的总体设计思路,介绍了这一平台的开发与运行环境、主要功能模块设计和实现方法。该平台已成功应用于珠江三角洲区域。通过广东省环境保护公众网信息平台,实时更新各个站点最新的空气监测数据,为广东开展环境整治工作以及居民日常出行提供参考。 相似文献
785.
Mishra VK Upadhyay AR Pandey SK Tripathi BD 《Environmental monitoring and assessment》2008,141(1-3):49-58
Five heavy metals Cu, Cd, Mn, Pb and Hg were found in high concentration from three sampling sites located in Asia’s largest
anthropogenic lake Govind Ballabh Pant GBP Sagar. Concentrations of these heavy metals were measured in Water, bottom sediment
and in different parts of the aquatic macrophytes collected from the reservoir. Plants collected from the lake were Eichhornia crassipes, Azolla pinnata, Lemna minor, Spirodela polyrrhiza, Potamogeton pectinatus, Marsilea quadrifolia, Pistia stratiotes, Ipomea aquqtica, Potamogeton crispus, Hydrilla verticillata and Aponogeton natans. These plants have shown the high concentrations of Cu, Cd, Mn, Pb and Hg in their different parts due to bioaccumulation.
In general plant roots exhibited higher concentrations of heavy metals than corresponding sediments. A comparison between
different morphological tissues of the sampled plants reveled the metal concentration in following order roots > leaves. Analyses
of bottom sediment indicated the higher concentrations of Cd, Mn, Cu and Pb. Strong positive correlations were obtained between
the metals in water and in plants as well as between metal in sediment and in plants. Indicating the potential of these plants
for pollution monitoring of these metals. 相似文献
786.
Global environmental and societal changes threaten the cultures of indigenous peoples and local communities (IPLC). Despite the importance of IPLC worldviews and knowledge to sustaining human well-being and biodiversity, risks to these cultural resources are commonly neglected in environmental governance, in part because impacts can be indirect and therefore difficult to evaluate. Here, we investigate the connectivity of values associated with the relationship Ngātiwai (a New Zealand Māori tribe) have with their environment. We show that mapping the architecture of values-environment relationships enables assessment of how deep into culture the impacts of environmental change or policy can cascade. Our results detail how loss of access to key environmental elements could potentially have extensive direct and cascading impacts on the cultural values of Ngātiwai, including environmental responsibilities. Thus, considering only direct effects of environmental change or policy on cultural resources, or treating IPLC social-ecological relations simplistically, can severely underestimate threats to cultures.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-021-01670-3. 相似文献
787.
Olivia Langmead Abigail McQuatters-Gollop Laurence D. Mee Jana Friedrich Alison J. Gilbert Marian-Traian Gomoiu Emma L. Jackson Ståle Knudsen Galina Minicheva Valentina Todorova 《Ecological modelling》2009
During recent decades anthropogenic activities have dramatically impacted the Black Sea ecosystem. High levels of riverine nutrient input during the 1970s and 1980s caused eutrophic conditions including intense algal blooms resulting in hypoxia and the subsequent collapse of benthic habitats on the northwestern shelf. Intense fishing pressure also depleted stocks of many apex predators, contributing to an increase in planktivorous fish that are now the focus of fishing efforts. Additionally, the Black Sea's ecosystem changed even further with the introduction of exotic species. Economic collapse of the surrounding socialist republics in the early 1990s resulted in decreased nutrient loading which has allowed the Black Sea ecosystem to start to recover, but under rapidly changing economic and political conditions, future recovery is uncertain. 相似文献
788.
Simple ecological models that mostly operate with population densities using continuous variables, explain quite well the behavior of real populations. In this work we propose and discuss the continuous dynamics of a system of three species, which belongs to the well-known family of Lotka–Volterra models. In particular, the proposed model includes direct effects such as predation and competition among species, and indirect effects such as refuge. The model is proposed to explain recent studies about a group of crustacean (amphipods of genus Hyallela) found in all the plain streams and shallow lakes of the American continent. The studied system includes three compartments: algae, a strictly herbivore amphipod and an omnivore (herbivore and carnivore) one. The analysis of the model shows that there are stable extinction equilibria throughout all the parameters’ space. There are also equilibria with stable coexistence of the three species and two interesting binary equilibria: one with stable coexistence of algae and herbivore and other with coexistence between algae and omnivore amphipods. The presence of Allee effect in the algae growth and the existence of refuge for the herbivore amphipod (prey) determine a bottom-up control. 相似文献
789.
四种岭南水果种植系统的能值、经济与土壤整合分析 总被引:2,自引:0,他引:2
综合运用能值、经济与土壤生态学分析方法,定量研究了番石榴(Psidium guajava Linn)、黄皮(Clausena lansium Skeels)、枇杷(Eriobotrya japonica Lindl)、葡萄柚(Citrus paradisi Maef)4种岭南水果种植系统的物质流、能最流和货币流,综合分析其自然资源基础、经济发展状况及可持续发展程度,并将土壤有机质的消耗纳入不可更新自然资源能值投人分析,为岭南水果业的可持续发展提供科学依据.能值分析表明,4个水果种植系统的可持续发展能力依次为:葡萄柚(0.94)>枇杷(0.15)>番石榴(0.14)>黄皮(0.10).土壤有机质分布与变化分析表明,4种水果种植系统的土壤有机质消耗量依次为:葡萄柚>黄皮>枇杷>番石榴.经济分析表明,4个水果种植系统的经济效益依次为:葡萄柚>番石榴>枇杷>黄皮.综合分析表明,番石榴、黄皮、枇杷三个系统的水果生产效率有待进一步提高;葡萄柚种植系统的水果生产效率、可持续发展能力和经济效益较高,但其对土壤有机质的消耗强度在四个系统中是最高的,这一点在水土流失严重的丘陵地区显然是不容忽视的.同时,如何降低系统在市场交换中的交换性资产流失是四个系统共同面对的问题. 相似文献
790.