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951.
952.
张颖 《中国环境管理干部学院学报》2010,20(3):69-72
昌黎县近几年环境空气监测数据显示:大气环境质量有所下降,环境受到轻微污染。污染产生的主要原因为冬季燃煤造成污染物排放增加及风沙、扬尘影响,结合本县采用发展集中供热、改善燃料构成、提升监管力度、严格环境管理、加大资金投入、开展末端治理等防治实践进行探讨。 相似文献
953.
Abstract: Quantifying the extent to which existing reserves meet conservation objectives and identifying gaps in coverage are vital to developing systematic protected‐area networks. Despite widespread recognition of the Philippines as a global priority for marine conservation, limited work has been undertaken to evaluate the conservation effectiveness of existing marine protected areas (MPAs). Targets for MPA coverage in the Philippines have been specified in the 1998 Fisheries Code legislation, which calls for 15% of coastal municipal waters (within 15 km of the coastline) to be protected within no‐take MPAs, and the Philippine Marine Sanctuary Strategy (2004), which aims to protect 10% of coral reef area in no‐take MPAs by 2020. We used a newly compiled database of nearly 1000 MPAs to measure progress toward these targets. We evaluated conservation effectiveness of MPAs in two ways. First, we determined the degree to which marine bioregions and conservation priority areas are represented within existing MPAs. Second, we assessed the size and spacing patterns of reserves in terms of best‐practice recommendations. We found that the current extent and distribution of MPAs does not adequately represent biodiversity. At present just 0.5% of municipal waters and 2.7–3.4% of coral reef area in the Philippines are protected in no‐take MPAs. Moreover, 85% of no‐take area is in just two sites; 90% of MPAs are <1 km2. Nevertheless, distances between existing MPAs should ensure larval connectivity between them, providing opportunities to develop regional‐scale MPA networks. Despite the considerable success of community‐based approaches to MPA implementation in the Philippines, this strategy will not be sufficient to meet conservation targets, even under a best‐case scenario for future MPA establishment. We recommend that implementation of community‐based MPAs be supplemented by designation of additional large no‐take areas specifically located to address conservation targets. 相似文献
954.
成都冬季典型辐射逆温过程分析 总被引:1,自引:0,他引:1
本文利用测温声雷达的探测结果,借助同期探空和地面观测资料,分析了成都平原典型辐射逆温的生消演变规律,指出了其主要特征。这些结果对气候资源利用、污染气象条件的研究等具有重要意义。 相似文献
955.
Rolando Bravo Jerry R. Rogers Theodore G. Cleveland 《Journal of the American Water Resources Association》1996,32(1):39-46
ABSTRACT: Determination of the boundary conditions for modeling ground water flow is a critical point especially in regional models. Normally the regional models require model areas that are greater than the given area of interest. This work focuses on the prediction of hydraulic heads in regional models using flux boundary conditions. The model uses flux boundary conditions that were estimated using a radial flow analog and Darcy's law. The regional model that is presented uses no parameter identification (inverse estimation) procedures. In the present work, the Houston area was used. The simulation of the hydrological conditions of the Chicot and Evangeline Aquifers that underlie the Houston area were made using the available information about the geological profile in the Houston region and the current information about the existing production wells. The regional model works as a forward problem. The system parameters such as hydraulic conductivity, specific storage, and hydrological stresses were specified, and the model predicts the hydraulic head. Actual data from piezometers operated by the U.S. Geological Survey (USGS) in many places throughout Houston were used as initial conditions. Some piezometric head data were generated using the regional variable theory called kriging to supply head estimates in areas where data were unavailable. The Modular Three Dimensional Finite Difference Groundwater Flow Model developed by the USGS was used to predict the hydraulic heads. The predicted ground water heads are compared to the actual data. The results show that the model performs well for locations where data were available. 相似文献
956.
介绍了国外有关腐蚀性空气环境的分级标准及其检测方法。环境中的腐蚀性气体可对电子元器件及自动控制设备产生腐蚀,影响其性能。根据腐蚀性的严重程度,美国仪器学会标准中将腐蚀性空气环境分为四级。环境腐蚀性置于腐蚀性环境中的铜试条进行检测。 相似文献
957.
化工厂排放SO2对周围植物的影响 总被引:6,自引:0,他引:6
对某厂区及常年盛行风下风向地区植物受SO2危害情况进行了调查,并测定了部分植物叶片中的硫含量。从植物叶片中的硫含量可间接地判断大气被SO2污染的程度及植物对SO2吸收与抵抗能力的强弱。 相似文献
958.
氧化镁法脱硫,具有工艺流程短、脱硫效率高等优点,对控制烟气SO2造成的大气污染是一种行之有效的办法,具有推广应用的广阔前景。 相似文献
959.
ABSTRACTHigh seas fisheries remain one of the least transparent global production practices. Distance from shore, coupled with the highly mobile nature of fish stocks, has put attention on new monitoring, control and surveillance technologies to collect spatially referenced data on the location of fishing vessels, gears and even fish stocks and eradicate illegal, unreported and unregulated fishing activity. Faced with their nascent implementation, research is yet to address how these technologies are reconfiguring the roles and responsibilities of public and private actors involved in fisheries management, including who collects and controls fisheries related information. In this paper, we compare three monitoring, control and surveillance technologies that are gaining traction in fisheries; the use of private fish attraction devices in oceanic tuna fisheries, unmanned public drones for marine surveillance and global satellite monitoring of fishing vessels. In doing so, we question how different configurations of actors are structuring flows of information and with what effect on sustainability performance of high seas fisheries. We also explore how these technologies configure new (and imagined) geographies of high seas fisheries which challenge existing modes of fisheries management. 相似文献
960.