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641.
基于SPSS的盐城自然保护区近海海域水质污染状况的分析 总被引:1,自引:0,他引:1
根据盐城自然保护区近海海域的监测数据,选取五大类代表指标,9个监测断面,运用SPSS统计软件对污染因子及主成分进行分析,研究主要污染因子的组合,并对相应污染源进行分析;通过聚类分析对近海海域的监测点及各监测点的污染数据进行分类,优化近海海域监测站点的分布,分析结果表明盐城自然保护区近海海域整体属于面源污染类型,但整个海域由北到南污染情况略有不同,海域北部偏重于化学污染类型,南部偏重于面源污染类型,分析的结论为该区域的环境监测及污染治理提供了重要的信息和依据. 相似文献
642.
烟台市养虾废水排放及控制 总被引:6,自引:0,他引:6
本文通过对人工养殖对虾的生长过程中废水排水排放量及以COD为主要污染因子的污染物排放量的现场调查和则,基本摸清了对虾养殖业对烟台近海海域的污染贡献。同时结合当地实际情况,讨论了控制措施。 相似文献
643.
本文提出中国东南沿海与西南日本内带中生代火山活动时代与旋回对比意见,阐述两带火山喷发与侵入活动时序和交替式演变。两带火山活动时差呈现超前、滞后式迁移性。两带内部火山活动又显示垂直与平行火山岩带的双向迁移性。 相似文献
644.
辽东湾东部砂岸严重蚀退及其原因分析 总被引:1,自引:0,他引:1
辽东湾东部砂岸属冰后期淤长岸。近些年来遭到强烈侵蚀。不仅岬角、平直砂岸在蚀退.连一向稳定的湾内淤长岸也在转侵后退。目前,调查区100km海岸约有2/3的岸段出现严重蚀退现象,不少岸段年蚀退率已超过6m.有的沿海公路多次内迁,引起沙滩粗化、泻湖水量加大、海水倒灌、土地咸化等一系列严重灾害。 相似文献
645.
646.
Michael J. Hilton 《Environmental management》1994,18(6):815-829
The purpose of New Zealand's Resource Management Act (1991) is to promote the sustainable management of natural and physical
resources. Coastal sand mining may be consistent with this purpose where: (1) extractions occur from sediment systems open
to inputs of sediment, and the volumes extracted do not limit the natural development, physical characteristics, and ecological
diversity of the coastal environments affected; or (2) extractions from palimpsest or relict sedimentary deposits occur at
a rate where the rate of extraction is insignificant compared with the volume of the resource.
The response of coastal sand mining companies and consent-granting authorities to the requirements of the Resource Management
Act (1991) are examined with respect to recent applications to mine sand from a coastal sand body in the Hauraki Gulf, New
Zealand. The assessments of environmental effects (AEE) submitted in support of these applications do not establish the sustainability
of the sand mining operations. Specifically they do not define the dimensions of the active sediment system, quantify the
volume of the related resource, or state the period within which sustainability is achievable. Further, the AEE do not consider
the cumulative effects of the extractions, either in terms of the total volume of sand mined or the cumulative effects of
different anthropogenic activities.
The test of sustainability demands a quality of information and understanding of coastal systems that is well beyond that
obtained in the past or accepted at present. There is a clear need for New Zealand's resource management legislation to be
supplemented by technical guidelines that help ensure the test of sustainability is rigorously applied. 相似文献
647.
648.
中国海岸地带面临的重大环境变化与灾害及其防御对策 总被引:16,自引:3,他引:16
中国海岸地带面向21世纪的持续发展,面临着相对海面加速上升和热带气旋、风暴潮与低洼地洪涝不断加剧以及海岸环境急剧恶化等一系列重大环境变化与灾害问题。本文着重分析相对海面上升、热带气旋、风暴潮与洪水灾害以及海岸环境污染的特征、演变趋势及防御对策。 相似文献
649.
Anthropogenic-driven changes with focus on the coastal zone of Mauritius, south-western Indian Ocean
R. Ramessur 《Regional Environmental Change》2002,3(1-3):99-106
Some 44% of the world's population lives within 150 km of the coast and mass migration towards the coast will continue in
the decades ahead. Degrading and exhaustive uses of land, water and other coastal resources and disruption of environmental
processes through degradation of environmental quality and loss of critical terrestrial and aquatic habitats can lead to serious
deleterious impacts on the health and productivity of coastal ecosystems. Following the Arusha Resolution (1993), the Seychelles
Statement (1996) and the Colombo CZM Workshop (1999), the need for integrated coastal zone management has become critical
because of the limited land resources and unproportional domination of coastal areas in the wider Caribbean and Indian Ocean/
Pacific island states. The coastal zone of Mauritius (1,850 km2, 20°S, 58°E, south-western Indian Ocean, 1.12 million inhabitants) was redefined in 1997 in the Environmental Protection
Act of 1991 [Part VII (Act 34)] to include all islets within the Exclusive Economic Zone (EEZ; 1.7 million km2). During the 1980s, the Mauritian economy underwent major structural changes successfully, with a rapid phase of industrialization
diversifying into two major activities, textiles and tourism. Existing reports and data in a common framework have to be synthesized
and organized to fill existing gaps in knowledge with data collection and scientific inquiries, to identify social and economic
drivers and to relate socioeconomic change to demands for environmental resources (land use, water resources, marine systems)
and environmental impacts as proposed under the MERMAID (Mauritius Environmental Resource Management and Industrial Development)
project. Nutrient flux and sediment trace metal contamination studies are currently underway to investigate different watersheds
impacted by agricultural, urban and industrial activities in the north-west of the island. There is a pressing need to integrate
the natural sciences with socioeconomic disciplines as proposed by the International Human Dimensions Program (IHDP) for an
integrated management of coastal zones. Three integrated pilot projects in the Pacific-Indian Ocean and wider Caribbean as
identified by Land Ocean Interaction in the Coastal Zone (LOICZ) in the future, including current status and changes in material
fluxes from drainage basins, transboundary impacts from the ocean and atmospheric inputs, could elucidate the land–sea interactions
and human dimensions of change on small islands. The sustainability of marine resources and the conservation of biological
diversity will depend on a critical understanding of linkages between human activities and ecological responses and upon a
citizenry that assumes ownership of these regions. Case studies would also help in investigating how humans affect transport
pathways and biogeochemical cycles in small island states.
Electronic Publication 相似文献
650.
ABSTRACT: Wetlands exist in a transition zone between aquatic and terrestrial environments which can be altered by subtle changes in hydrology. Twentieth century climate records show that the United States is generally experiencing a trend towards a wetter, warmer climate; some climate models suggest that this trend will continue and possibly intensify over the next 100 years. Wetlands that are most likely to be affected by these and other potential changes (e.g., sea‐level rise) associated with atmospheric carbon enrichment include permafrost wetlands, coastal and estuanne wetlands, peat lands, alpine wetlands, and prairie pothole wetlands. Potential impacts range from changes in community structure to changes in ecological function, and from extirpation to enhancement. Wetlands (particularly boreal peat‐lands) play an important role in the global carbon cycle, generally sequestering carbon in the form of biomass, methane, dissolved organic material and organic sediment. Wetlands that are drained or partially dried can become a net source of methane and carbon dioxide to the atmosphere, serving as a positive biotic feedback to global warming. Policy options for minimizing the adverse impacts of climate change on wetland ecosystems include the reduction of current anthropogenic stresses, allowing for inland migration of coastal wetlands as sea‐level rises, active management to preserve wetland hydrology, and a wide range of other management and restoration options. 相似文献