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251.
提出了城市生活垃圾填埋处置及资源化利用的循环经济产业模式,分析论述了该模式实施的关键点及其资源化优势,并通过案例估算突出其投资优势,最后提出了该模式产业化应用的发展建议. 相似文献
252.
This study evaluates the spatial patterns of land occupation and their relationship to water quality in the Cuiabá River watershed, one of the main affluents of the Pantanal floodplain. The impact of farming and other land occupation forms were studied using a three year time series. Monitoring included 15 parameters at 21 stations with a total of 1266 different samples. Ten stations along the Cuiabá River were ordinated by Principal Component Analysis (PCA). For an exploratory analysis in the spatial domain, sub-basins of the Cuiabá watershed were classified according to mean concentrations of selected water quality parameters. Supervised classification of digital Landsat ETM imagery and standard GIS techniques were applied to parameterize land use and occupation according to a watershed scale. Redundancy Analysis (RDA) was then used to evaluate impacts of environmental and socio-economic factors on water quality.A Cuiabá headwater station only shows slightly elevated total coliform counts and concentrations of nutrients in the river after it passes regions of extensive cattle farming. After the confluence with the Manso River, nutrient and COD concentrations increase significantly, receiving loads from sub-basins under intensive agricultural land use, with mean annual concentrations up to 1.74 mg/L of total nitrogen (Kjedahl). Sub-watersheds with intensive fishing culture activities were shown to have significant impact on nitrogen concentrations, reaching mean concentrations of 2.66 mg/L of total nitrogen in the affluents. Most serious biological and chemical water pollution can be observed at stream outlets in the urban agglomeration of Cuiabá/Várzea Grande. Affluent pollution is reflected in the water quality of the Cuiabá River: subsequent monitoring stations in the urban area are ordinated on a gradient of increasing degradation of chemical and biological water quality. The auto-depuration capacity of the Cuiabá River is intact, but elevated concentrations of Phosphorous and Chemical Oxygen Demand can be observed as far away as the Pantanal floodplain, about 120 km downstream from the urban agglomeration. 相似文献
253.
Urban Air Pollution Patterns, Land Use, and Thermal Landscape: An Examination of the Linkage Using GIS 总被引:1,自引:0,他引:1
This article investigates the relationship of local air pollution pattern with urban land use and with urban thermal landscape
using a GIS approach. Ambient air quality measurements for sulfur dioxide, nitrogen oxide, carbon monoxide, total suspended
particles, and dust level were obtained for Guangzhou City in South China between 1981 and 2000. Landsat TM images and aerial
photo derived maps were used to examine city's land use and land cover at different times and changes. Landsat thermal infrared
data were employed to compute land surface temperatures and to assess urban thermal patterns. Relationships among the spatial
patterns of air pollution, land use, and thermal landscape were sought through GIS and correlation analyses. Results show
that the spatial patterns of air pollutants probed were positively correlated with urban built-up density, and with satellite
derived land surface temperature values, particularly with measurements taken during the summer. It is suggested that further
studies investigate the mechanisms of this linkage, and that remote sensing of air pollution delves into how the energy interacts
with the atmosphere and the environment and how sensors see pollutants. Thermal infrared imagery could play a unique role
in monitoring and modeling atmospheric pollution. 相似文献
254.
Coppedge BR Engle DM Masters RE Gregory MS 《Environmental monitoring and assessment》2006,118(1-3):125-145
We utilized landscape and breeding bird assemblage data from three Breeding Bird Survey (BBS) routes sampled from 1965–1995
to develop and test a grassland integrity index (GII) in a mixed-grass prairie area of Oklahoma. The overall study region
is extensively fragmented from long-term agricultural activity, and native habitat remnants have been degraded by recent encroachment
of woody vegetation, namely eastern redcedar (Juniperus virginiana L.). The 50 individual bird survey points along the BBS routes, known as stops, were used as sample sites. Our process first
focused on developing a grassland disturbance index (GDI) as a measure of cumulative landscape disturbances for these sites.
The GDI was based on five key landscape variables identified in an earlier species-level study of long-term avian community
dynamics: total tree, shrub, and herbaceous vegetation cover indices, overall mean landscape patch size, and grassland patch
core size. The GII was then developed based on breeding bird assemblage data. Assemblages were based on commonly used response
guilds reflective of five avian life history parameters: foraging mode/location, nesting location, habitat specificity, migratory
pattern, and dietary guild. We tested the response of 78 candidate assemblage metrics to the GDI, and eliminated those with
no or poor response or with high correlations (redundant), resulting in 13 metrics for use in the final index. Individual
metric scores were scaled to fall between 0 and 10, and the cumulative index to range from 0 to 100. Although broader application
and refinement are possible, the avian-based GII has an advantage over labor-intensive, habitat-based monitoring in that the
GII is derived from readily available long-term BBS data. Therefore, the GII shows promise as an inexpensive tool that could
easily be applied over other areas to monitor changes in regional grassland conditions. 相似文献
255.
主题公园的体验化设计模式研究——以西安大唐芙蓉园为例 总被引:2,自引:0,他引:2
主题公园成功的关键是根据游客的需要为其提供足够的体验,吸引与留住游客并且增加游客的重游率。从体验经济的角度,提出主题公园产品的核心就是体验。分析了主题公园体验的影响因素、类型和体验化设计模式,指出主题公园的体验化设计能力将是主题公园核心竞争力所在,探讨了西安大唐芙蓉园的体验化设计模式。 相似文献
256.
代伟 《中国环境管理干部学院学报》2012,22(3):73-75
OBTL模式是以明确的目标和成果为导向,以学生为中心,以培养学生适应未来岗位要求的能力和素质为根本目的的教育模式。借鉴OBTL教学模式及其理念,依据市场营销专业的人才培养目标,确立了数据处理能力、案例分析能力和数学建模能力的能力目标,设计相匹配的多种数学实践活动,并构建多元化评估体系,旨在增强教学的针对性和实效性,提升高职学生的数学应用能力。 相似文献
257.
为了研究非稳定状态下生物除磷的特点,采用序批式间歇反应器(SBR),通过不同的进水方式(连续进水和瞬时进水),系统地考察了进水体积、NOX-N、限制曝气等因素对除磷过程的影响。结果表明,在温度为(23±0.5)℃、pH为7.0~8.0时,厌氧搅拌期连续进水的比释磷量(单位质量污泥(以MLSS计)的释磷量(以PO43-P计))比瞬时进水时高出42.11%。在运行条件相似的情况下,厌氧搅拌期的比释磷量与每周期进水体积无关。相对于连续进水,瞬时进水更有助于促进微生物利用有机底物进行自身的生长。限制曝气对连续进水和瞬时进水的释磷过程都存在明显的影响,在DO小于0.1mg/L的情况下,2者的比释磷量相对非限制曝气时分别降低了57.14%和55.56%。在连续进水时,NOX-N的反硝化结束伴随着释磷速率的突然升高。利用贮存作用并不能每次都成功地抑制丝状菌污泥膨胀。 相似文献
258.
259.
The spatial pattern of the different species in complex ecosystems reflects the underlying ecological processes. In this paper a second order moment function is proposed and tested to analyse the spatial distribution of a mark, which could be a tree characteristic such as diameter or height, between two different types of points, which could be two different tree species. The proposed function was a conditional density function based on the intertype Krs(d) function, incorporating as test function the correlation of the marks between pairs composed of points of different types. The results obtained in simulated and real plots prove that the function is capable of revealing the scale at which spatial correlation of the mark between two types of points exists. The proposed function allows the spatial association between individuals of different species at different life stages to be identified. This analysis may reveal information on species ecology and interspecific interactions in forest ecosystems. 相似文献
260.
采用实地调查与资料收集相结合的方法,以县(市)为基本地理单元建立江苏省陆栖濒危脊椎动物二元分布数据库;基于GIS技术,研究濒危动物物种丰富度格局;依据地理单元中物种组成的相似程度进行聚类分析,探讨江苏省濒危动物相似性分布格局。结果显示,江苏省陆栖濒危脊椎动物共有35科62属83种;西南部丘陵山区、盐城、连云港及启东地区濒危物种丰富度较高,江苏中部地区(主要为泰州和淮安)濒危物种丰富度较低,这与江苏省生物多样性分布热点基本一致,濒危物种丰富度与总物种丰富度之间呈极显著正相关关系(P<0.01,n=73),Pearson相关系数为0.869;依据物种组成相似性,当组间距离分别为23.8、20.6、18.8时,江苏省73个基本单元可聚为3、4、5组,该聚类结果表明江苏省陆栖濒危脊椎动物分布受自然地理亚区、地形地貌以及人为活动的共同影响。 相似文献