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参考流域生态健康评估综合指数法,通过构建陆域生态健康评估指标体系,综合利用生态格局指标、生态功能指标和生态压力指标对某河流域陆域生态健康进行评估。结果表明:该河流域陆域生态健康总体呈良好状态,流域内评估单元4得分最低,评价等级为一般;评估单元3得分最高,评价等级为优秀;其他评估单元陆域生态健康状态均为良好。生态健康状态总体表现为支流优于干流,干流上下游优于中游。景观破碎度、水源涵养功能指数、受保护地区面积占国土面积比例和面源污染负荷排放指数等是影响该河流域陆域生态健康状态的主要指标。通过对该河流域陆域生态健康进行评估,全面识别人类活动对流域陆域生态系统的影响范围和程度,为流域生态环境保护和可持续发展提供技术支撑。 相似文献
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低碳经济背景下的海港区景观重建是实现滨海城市可持续发展的重要途径之一。以威海新港景观环境建设为例,尝试提出低碳经济背景下现代海港区低碳景观规划的新模式,改观过去港区建设中仅注重服务功能和环境功用的传统理念,将港区低碳景观建设与港区生态性、文化性、艺术性有机结合起来,真正实现港区景观的可持续发展。 相似文献
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为减小海面溢油,自主设计吸油单元组装结构,利用数值模拟的方法,研究吸油单元形状对吸油性能的影响,通过对吸油阵列单元速度场、油组分浓度场分析发现:圆形结构吸油单元表面平滑,运动阻力小,与流体接触面积大,有利于增加吸油效率。采用上下间隔三角阵列方式对吸油单元进行排布,研究不同流速下阵列单元横向间距、纵向间距、分布排数以及入口含油浓度对吸油效率的影响,发现吸油单元的横向间距对吸油效率作用显著,而纵向间距和入口含油浓度对吸油效率影响不大,随吸油单元分布排数的增加,吸油效率趋于稳定。在工程应用范围内,保持阵列单元横向间距为1.5 D,运动速度低于1m/s,阵列单元的吸油效率能达到90%以上。 相似文献
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《资源开发与市场》2016,(9)
太平湾作为大连港距离东北腹地最近的港区,其建设将对营口港和大连港的腹地空间效应产生重要影响。从港城可达性、港城引力、港腹潜力三大空间指数,探讨太平湾港区建设对营口港和大连港的空间效应变化。研究结果发现:1太平湾港区的建设将进一步提升东北腹地城市与大连和营口各港区的空间联系,各空间指数提升幅度均呈现由南向北依次递减的趋势。2太平湾港区建设将进一步巩固大连港在东北腹地优势区的竞争优势,同时降低营口港在东北腹地优势区的绝对优势,在加剧大连港和营口港腹地竞争的同时,使营口港和大连港在东北腹地市场划分中呈现新的局面。随着大连发展重心向太平湾港区的转移,这种空间效应变化将更加明显。3太平湾港区建设加剧了大连各港区之间的内部竞争,容易造成港口资源浪费,因此大连在合理开发太平湾港区的同时,要注意内部港口之间的协同合作。 相似文献
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裴倩王利杜鹏崔晓琪焦雅楠 《资源开发与市场》2022,(10):1153-1160
以大连市旅顺口区为研究对象,基于绿色基础设施评价(GIA)方法,通过构建生态建设空间必要性模型识别生态源地。运用最小累积阻力模型和水文分析构建潜在陆域和水域生态廊道,基于重力模型分析生境斑块间的作用强度,利用连通评价指数提出生态网络构建方案。结果表明:(1)共构建219个生态建设空间斑块,其中面积大于1km2的有13个,多为极重要和较重要生态源地分布区,主要分布于研究区的南部和西北部山地。(2)初步生成的86条潜在陆域生态廊道中,重复廊道较多且交叉严重,而通过MCR模型构建的生态廊道缺少了水域生态廊道。(3)选取相互作用强度> 0.7的陆域生态廊道为重要陆域生态廊道,共17条;当汇水面积为2.25km2时,水域生态廊道为9条,能较好地连通各生态建设空间。(4)将生态建设空间和生态廊道的重要性评价分为三级,I级生态源地和生态廊道为生态网络的核心区,位于旅顺口区西南部,以林地、耕地和水域为主,有利于物种迁移,应优先考虑对其进行保护和建设。 相似文献
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以黑龙江垦区土地资源利用为例,运用统计分析方法,结合土地利用变化幅度和土地利用动态度等分析指标,对黑龙江垦区土地利用现状与动态变化进行分析。在此基础上,提出了黑龙江垦区土地利用中存在的主要问题:耕地面积总量增加,但人均耕地面积下降;土地资源利用效益有待提高;土地质量逐年下降,生态环境趋于恶化;部分农场场址道路建设用地过大,土地浪费现象严重;土地后备资源日益匮乏,开发整理复垦难度大等5个方面,并提出了相关的对策建议。 相似文献
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Spatial and Temporal Effects of Port Facilities Expansion on the Surface Area of Shallow Coral Reefs
There is a close relationship between ports and reef areas, mainly because reefs provide protection to vessels against extreme weather events like storms and hurricanes. This historical relationship has generated severe impacts on reef ecosystems. In order to identify the main impacts from the construction of port facilities in shallow coral reef areas, we analyzed and described the effects of land reclamation and coastal structure construction associated to port growth throughout a century in the Sistema Arrecifal Veracruzano National Park, Mexico. We used aerial photographs and maps of the nineteenth and early twentieth century to assess the impacts caused by port expansion activities on shallow coral reefs. Three types of impacts were identified: (a) direct reef area loss caused by landfills and perpendicular coastal structures construction leading to the loss of nearly 50 % of the fringing reef near to the port; (b) fragmentation in short- and medium-term scale, which affects two fringing reefs, and (c) long-term modification of coastal dynamics leading to sedimentation and loss of a complete reef area. On the eve of a new expansion of Veracruz Port, we used the New Port Project Plan, long-shore net drift geomorphic indicators and the port impact typology from the 100-year period assessment to evaluate a possible future scenario. The scenario describes how the new expansion project will repeat the three types of impacts affecting a whole reef area, which is currently part of the National Park. 相似文献
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Herbert G. Stangland Rolf T. Skrinde 《Journal of the American Water Resources Association》1975,11(4):783-795
ABSTRACT: Land development projects that are presumed to have regional impact according to the Florida Land and Water Management Act of 1972 are forced to minimize adverse environmental impact through a detailed procedure called Application for Development Approval (ADA). In Southeast Florida, as part of this review process, the water-supply and flooding conflicts must be resolved with the regional water management agency, Central and South Florida Flood Control District (FCD). This paper discusses the efforts to resolve these two conflicts for a large proposed residential development in Broward County, Florida. The project, as envisioned by Leadership Housing, Inc., places 25,000 dwelling units on the 3,960-acre site. The project is located in a flood prone area of the Hillsboro Canal Basin and is at the northwest edge of the Biscayne Aquifer. Significant land modification is required to flood-proof the project. The water-supply conflict was resolved only when the FCD was assured that the ultimate water demand for the project was balanced by the natural recharge to the site. Significant water-resources studies were required to produce these conflict resolutions. 相似文献
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Characteristics of major secondary ions in typical polluted atmospheric aerosols during autumn in central Taiwan 总被引:1,自引:0,他引:1
Fang GC Lin SC Chang SY Lin CY Chou CC Wu YJ Chen YC Chen WT Wu TL 《Journal of environmental management》2011,92(6):1520-1527
In autumn of 2008, the chemical characteristics of major secondary ionic aerosols at a suburban site in central Taiwan were measured during an annually occurring season of high pollution. The semicontinuous measurement system measured major soluble inorganic species, including NH(4)(+), NO(3)(-), and SO(4)(2-), in PM(10) with a 15 min resolution time. The atmospheric conditions, except for the influences of typhoons, were dominated by the local sea-land breeze with clear diurnal variations of meteorological parameters and air pollutant concentrations. To evaluate secondary aerosol formation at different ozone levels, daily ozone maximum concentration (O(3,daily max)) was used as an index of photochemical activity for dividing between the heavily polluted period (O(3,daily max) ≧80 ppb) and the lightly polluted period (O(3,daily max)<80 ppb). The concentrations of PM(10), NO(3)(-), SO(4)(2-), NH(4)(+) and total major ions during the heavily polluted period were 1.6, 1.9, 2.4, 2.7 and 2.3 times the concentrations during the lightly polluted period, respectively. Results showed that the daily maximum concentrations of PM(10) occurred around midnight and the daily maximum ozone concentration occurred during daytime. The average concentration of SO(2) was higher during daytime, which could be explained by the transportation of coastal industry emissions to the sampling site. In contrast, the high concentration of NO(2) at night was due to the land breeze flow that transport inland urban air masses toward this site. The simulations of breeze circulations and transitions were reflected in transports and distributions of these pollutants. During heavily polluted periods, NO(3)(-) and NH(4)(+) showed a clear diurnal variations with lower concentrations after midday, possibly due to the thermal volatilization of NH(4)NO(3) during daytime and transport of inland urban plume at night. The diurnal variation of PM(10) showed the similar pattern to that of NO(3)(-) and NH(4)(+) aerosols. This indicated that the formatted secondary aerosols in the inland urban area could be transported to the coastal area by the weak land breeze and deteriorated the air quality in the coastal area at night. 相似文献
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T. C. Daniel R. C. Wendt P. E. McGuire D. Stoffel 《Journal of the American Water Resources Association》1982,18(1):117-120
ABSTRACT: Loading rates derived from monitoring natural runoff from selected land uses are compared. Land uses selected for evaluation are construction sites, barnyards, and agriculture (dairying). Runoff volumes, sediment, and nutrient fractions were monitored and expressed as areal loadings for comparison purposes. Sediment yield and total phosphorus (total P) loss was directly proportional to runoff (m3/ha). In decreasing order, the loadings for sediment and total P were as follows: construction site > barnyard > general dairying. Runoff from the barnyard area was approximately 10 times higher in soluble phosphorus and ammonium nitrogen than the other land uses under investigation. Areal loss for nitrate nitrogen was highest from the construction site and was attributed to the higher volume of runoff per unit area. Results show that barnyards in a dairying watershed are potentially a major source of sediment and nutrients, especially those dissolved fractions which have the potential for immediate water quality impacts. Relative to general agricultural land, urban construction sites also appear to be a major source of sediment and nutrients. As with barnyard sites, however, the effect of such sites on water quality likely depends on proximity to surface water bodies and other watershed characteristics affecting delivery ratios of contaminants. 相似文献
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Environmental impact assessment of a proposed info-tech complex in East Calcutta wetlands 总被引:1,自引:0,他引:1
An info-tech complex is proposed for 286 acres (116 ha) of land within the East Calcutta wetlands. The proposed site is 15 km east of Kolkata city and only 8 km south of Dum Dum airport. The site is vacant, with pockets of agricultural land and a few degrading water-logged areas. In order to assess the likely impact of the proposed development on the environment, a rapid environmental impact assessment of an area of 10 km radius from the centre of the project site was carried out. The present status of the environment with respect to ambient air, surface water, groundwater, soil, landuse, noise, and socio-economics of the core and buffer zone has been documented and correlated with 24 project activities during construction, development and operational phases. The frequency of adverse impacts is greater than that of beneficial impacts. Out of the total adverse impacts 20 are short term, reversible and have a low magnitude. The total impact score for the proposed project is (–)468.75 and as per the Assessment Value Index Scale the environmental impact of the proposed project activities is no appreciable impact. But there are certain sectors where the environment will be adversely impacted. Therefore, appropriate measures have been suggested to ameliorate the adverse impacts. It is envisaged that if these measures are implemented then there will be an improvement in the quality of the environment, as well as life, by 687.5 units. 相似文献
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ESTIMATING TMDL BACKGROUND SUSPENDED SEDIMENT LOADING TO GREAT LAKES TRIBUTARIES FROM EXISTING DATA1
Peter J. Whiting 《Journal of the American Water Resources Association》2006,42(3):769-776
ABSTRACT: The total maximum daily load (TMDL) for suspended sediment is the maximum quantity of suspended sediment that can enter a waterway without affecting the beneficial uses of the waterway. It is calculated as the sum of permissible allotments of point sources of suspended sediment, permissible allotments of nonpoint sources of suspended sediment, background (natural) loading of suspended sediment, and a margin of safety. The goal of this project was to develop methods for estimating background levels of sediment loads in tributaries of the Great Lakes. Such quantification is key to determining permissible TMDL in waters that do not meet water quality standards under the Clean Water Act of 1972. Suspended sediment loading for 46 rivers was estimated from data collected at U.S. Geological Survey (USGS) gages. Land use and physiographic attributes were estimated for these gaged basins with a geographic information system (GIS). Basin attributes and sediment yield data are the basis for examining two approaches to estimating background suspended sediment loads. One method, based upon envelope curves of sediment yield and drainage area, will be shown to have considerable merit. A second method, based upon correlation of sediment yield to various basin attributes such as drainage area and land use, will be shown to be fraught with difficulties. 相似文献
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国内外生态足迹研究进展 总被引:9,自引:0,他引:9
在可持续发展的定量研究中,生态足迹形象地反映了人类经济活动对环境影响的程度,对地区可持续发展的决策具有一定的指导意义。本文阐述了:(1)生态足迹的理论背景、相关概念、计算方法以及与能值分析法、产品生命周期法和投入产出法等综合应用的趋势;(2)生态足迹在全球、国家、地区尺度上的研究成果,以及在国际贸易、能源、旅游、交通、饮食等领域的应用进展;(3)土地互斥假设、全球面积单位、等效因子取值以及研究尺度方面的局限性。最后,本文指出了在多指标整合、污染影响分析和家庭消费尺度研究等方面的研究趋势。 相似文献