共查询到20条相似文献，搜索用时 15 毫秒
1.
《Applied Geochemistry》2002,17(8):1029-1045
The advantages of quantitative environmental risk assessment techniques over the more commonly used qualitative approach is widely accepted. Yet, correct implementation of quantitative risk assessment is a difficult task, given the present state of understanding of the environmental processes. One important parameter related to the level of risk is the extent and geographic spread of pollutants. Geographic information systems (GIS) provide a very powerful and highly flexible tool that increases the sophistication of the risk assessment methodology. Through spatial representation, the estimated risk becomes more comprehensive, thus facilitating the decision making process. In addition, valuable qualitative information can be incorporated into the risk assessment procedure with the help of GIS. This paper illustrates a methodology which incorporates a probabilistic risk assessment model within a GIS. The case study utilised to illustrate the methodology is a large industrial area around a number of decommissioned minerals production and processing sites with known high heavy metal loads at Lavrio, Greece. The spatial distribution of Pb concentration in soils was derived from 425 soil samples collected over a total area of 120 km2. A risk assessment model was constructed to simulate and assess the risk associated with high Pb loads in soils in the study area. The methodology consists of a typical exposure assessment model, constructed for adult and child populations. The Pb exposure for both populations is compared with relevant reference dose levels providing hazard quotients. The results of the quantitative risk assessment study are analysed and presented in the form of GIS maps covering the study area. 相似文献
2.
Integration of RADARSAT and GIS modelling for estimating future Red River flood risk 总被引：1，自引：0，他引：1
A new geomatics-based approach for flood prediction was developed and used to model the magnitude and spatial extent of a
future Red River flood in southern Manitoba. This approach combines the statistical modelling capabilities of Markov (non-spatial)
analysis and logistic regression (spatial) within a geographic information system (GIS) environment, utilizing modelling inputs
derived from remotely sensed RADARSAT imagery and other digital geographic data. The 1997 Red River flood was the second largest
in recorded history, and the largest for which accurate data are available. The results indicate: (i) a flood “one time interval-in
terms of 3 days time unit measurement- larger in area” than the 1997 flood is expected to affect 17.6% more land (an additional
47.6 km2) within the study area compared to 1997 levels based on Markovian probability derived from observations from the 1997 event;
and (ii) the majority of this excess flooding will take place on agricultural land; no additional communities are expected
to be at risk. Quantitative assessment verified the capability of this modelling approach for producing statistically significant
results. The methodology used in this research would be easily transferable to other areas, and may provide the basis for
a viable alternative to conventional hydrologic-based flood prediction approaches
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
3.
M. A. Hamadouche K. Mederbal L. Kouri Z. Regagba Y. Fekir D. Anteur 《Arabian Journal of Geosciences》2014,7(2):419-434
This paper presents a geographic information system (GIS)-based multicriteria decision-making approach for biodiversity preservation of the Ahaggar National Park in Algeria. This tool named spatial decision-making aid (SDMA) enables decision makers to evaluate the relative priorities of conserving the biodiversity in protected areas basing on a set of preferences, criteria and indicators of the area. In this study, we have developed conceptual and methodological solutions to integrate outranking methods (such as elimination and choice to translate reality TRI, preference ranking organizational methods and analytical hierarchy process) of multicriteria analysis in the GIS software to enhance its potential as tools of spatial decision support in land management problems. We integrated the results and other data relevant studied area in a GIS as a starting point for our SDMA prototype for resources management. Through the application, we have designed functionalities that allow producing maps of areas which needed urgent preservation. These methods are more appropriate to decision-making problems and their integration into GIS software (ArcView GIS 3.2 software from Environmental Systems Research Institute) that constitutes a powerful tool of spatial decision-making aid. 相似文献
4.
利用矢量数据结构的地理信息系统(GIS)软件和模拟模型集成开发流域面源污染管理系统.以上海市苏州河流域为例,通过土地利用类型、土壤类型、子流域等图层的叠加,将流域空间分割为一系列不规则的矢量多边形,并将这些矢量多边形作为非点源模拟的空间单元;利用组件式地理信息系统平台MapX、Surfer等,设计和开发了无缝集成的苏州河面源管理信息系统的结构、功能和数据库组成,并初步建立了可运行的苏州河流域面源管理信息系统.在系统的支持下,可有效地实现流域面源污染负荷估算、面源污染指数评价、单位面源负荷的等值线绘制以及面源污染的总量控制等功能.所开发的系统,既是面源污染专业软件开发的有益尝试,同时也是流域数字化环境管理的有益探索. 相似文献
5.
Elsayed Said Mohamed 《Arabian Journal of Geosciences》2013,6(12):4647-4659
This study aims to use spatial analyses and a geographic information system (GIS) to assess the environmental sensitivity for desertification in the north Sinai Peninsula, Egypt. Based on the Mediterranean Desertification and Land Use (MEDALUS) approach and the characteristics of the study area, a regional model was developed using GIS. Five main indicators of desertification including soil, climate, erosion, plant cover, and management were considered for estimating the environmental sensitivity to desertification. A spatial analyst extension Arc-GIS 10 software was used for matching the thematic layers and assessing the desertification index, of which the map of environmentally sensitive areas of the north Sinai Peninsula is produced. The obtained data reveals that 65 % of north Sinai is characterized by very severe sensitivity to desertification while the low sensitive one exhibits only 1.2 %. The moderately sensitive area occupies approximately 23 % of the study area. ETM+ and SPOT images are recommended to monitor sensitivity. The MEDALUS model was developed under the Egyptians to assess desertification sensitivity. 相似文献
6.
Catchment scale spatial variability of soil salt content in agricultural oasis,Northwest China 总被引：4，自引：0，他引：4
Soil salinization is a serious environmental problem in the world, especially in arid and semi-arid regions. Therefore, estimating
spatial variability of soil salinity plays an important role in environmental sciences. Aiming at the problem of soil salinization
inside an oasis, a case study was carried out at the Sangong River catchment in Xinjiang province, northwest China. Methods
of classical statistics, geostatistics, remote sensing (RS) and geographic information system (GIS) were applied to estimate
the spatial variability of soil salt content in the topsoil (0–20 cm) and its relationship with landscape structure at catchment
scale. The objective of this study was to provide a scientific basis to understand the heterogeneous of spatial distribution
of soil salt content at a large scale. The results revealed that (1) elevation of landform was a key factor for soil salt
content’s spatial variability, and soil salt content had a strong spatial autocorrelation, which was mainly induced by structural
factors. (2) Mapping of soil salt content by Kriging and comparing it with landscape maps showed that area of soil salinization
in old oasis was smaller than that in new oasis, and degree of soil salinization in old oasis was also lower than that in
the new one. Among all landscapes, cropland was mostly affected by salinity, with 38.8% of the cropland in new oasis moderately
affected by soil salinity, and 8.54% in old oasis. 相似文献
7.
Thomas R. Allen Harri T. Tolvanen George F. Oertel George M. McLeod 《Estuaries and Coasts》2007,30(6):959-977
Spatial patterns of environmental processes are intrinsic yet complex components of estuaries. Spatial characterization of environmental gradients is a necessary step to better understand and classify estuarine environments. A geographic information system is developed to analyze the major abiotic environmental processes, to evaluate accuracy and spatial uncertainty, and to analyze potential zonation within the choked coastal lagoon of Chincoteague Bay in Maryland and Virginia, USA. Spatially extensive grid-based models of environmental gradients are constructed from existing geospatial and environmental databases, including tidal prism, bathymetry, salinity, wave exposure, and Secchi disk depth. Integration of wetland boundaries and bathymetric data provide for full basin analysis of flushing and tidal prism. Multivariate Principal Components Analysis demonstrates the covariation among gradients and provides an empirical approach to mapping multidimensional zones within the lagoon. The project documents the development of an estuarine geographic information system that can be used to analyze and compare estuarine environments and provide data for environmental decision making. 相似文献
8.
Pan Ming Huang Shan-Li Wang Yu-Min Tzou Yibin Huang Boqi Weng Shunyao Zhuang Ming Kuang Wang 《Environmental Earth Sciences》2013,68(8):2199-2209
Soil is a vital biological habitat, which is of primary importance in determining and regulating biological activity and biodiversity. Therefore, it is Earth’s most important resource in sustaining both belowground and aboveground biological activities. Biodiversity versus landscape diversity and land use practices in multifunctional landscapes have been addressed. Humans have so manipulated nature that few locations in the world remain without human influence, causing unforeseen changes in ecosystem continuously and biodiversity. Among the environmental compartments, about 90 % of environmental pollutants are bound with soil particles. The soil-bound pollutants may be released to the soil solution through physical, chemical and biological interfacial interactions and pose a threat to biodiversity and ecosystem integrity. These interfacial interactions are especially important in the rhizosphere, where the kinds and concentrations of biomolecules are different from the bulk soil because of intense biological activity. These biomolecules affect biogeochemical processes, soil microbial ecology, nutrient and contaminant dynamics, abiotic and biotic factors, and soil biodiversity through allelopathic interactions. Soil interfacial interactions under different pedogenic processes and anthropogenic activity in relation to belowground biodiversity and the impact on aboveground biodiversity, productivity and integrity should be an important and exciting area of science for years to come. 相似文献
9.
10.
Spatial variability of soil organic matter and nutrients in paddy fields at various scales in southeast China 总被引：2，自引：0，他引：2
Xingmei Liu Keli Zhao Jianming Xu Minghua Zhang Bing Si Fan Wang 《Environmental Geology》2008,53(5):1139-1147
The present study examines the spatial dependency of soil organic matter and nutrients in paddy fields at three different
scales using geostatistics and geographic information system techniques (GIS). The spatial variability of soil organic matter
(SOM), total nitrogen (TN) and available phosphorus (AP) has been characterized using a total of 460, 131 and 64 samples that
were, respectively, collected from the Hangzhou–Jiaxing–Huzhou (HJH) Plain (10 km), Pinghu county (1,000 m) and a test plot
area (100 m) within the Pinghu county, Zhejiang province of the southeast China. Semivariograms showed that the SOM and TN
had moderate spatial dependency on the large scale of HJH plain and moderate scale of Pinghu county with long spatial correlation
distances. At the moderate scale of Pinghu county and the small scale of a test plot area, the AP data did not show any spatial
correlation, but had moderate spatial dependency in HJH plain. Spherical and exponential variogram models were best fitted
to all these soil properties. Maps of SOM and TN were generated through interpolation of measured values by ordinary kriging,
and AP by lognormal kriging. This study suggests that precision management of SOM and TN is feasible at all scales, and precision
management of AP is feasible at large scales. 相似文献
11.
Spatial analysis and hazard assessment of mercury in soil around the coal-fired power plant: a case study from the city of Baoji, China 总被引：2，自引：0，他引：2
Based on systematic sampling of soil around the coal-fired power plant (CFPP), the content of Hg was determined, using atomic
fluorescence spectrometry. The result shows that the content of Hg in soil is different horizontally and vertically, ranges
from 0.137 to 2.105 mg/kg (the average value is 0.606 mg/kg) and is more than the average content of Hg in Shaanxi, Chinese
and world soil. In this study, spatial distribution and hazard assessment of mercury in soils around a CFPP were investigated
using statistics, geostatistics and geographic information system (GIS) techniques. Ordinary kriging was carried out to map
the spatial patterns of mercury and disjunctive kriging was used to quantify the probability of the Hg concentration higher
than the threshold. The maps show that the spatial variability of the Hg concentration in soils was apparent. These results
of this study could provide valuable information for risk assessment of environmental Hg pollution and decision support.
An erratum to this article can be found at 相似文献
12.
Iason Papaioannou Daniel Straub 《Georisk: Assessment and Management of Risk for Engineered Systems and Geohazards》2017,11(1):116-128
ABSTRACTField data is commonly used to determine soil parameters for geotechnical analysis. Bayesian analysis allows combining field data with other information on soil parameters in a consistent manner. We show that the spatial variability of the soil properties and the associated measurements can be captured through two different modelling approaches. In the first approach, a single random variable (RV) represents the soil property within the area of interest, while the second approach models the spatial variability explicitly with a random field (RF). We apply the Bayesian concept exemplarily to the reliability assessment of a shallow foundation in a silty soil with spatially variable data. We show that the simpler RV approach is applicable in cases where the measurements do not influence the correlation structure of the soil property at the vicinity of the foundation. In other cases, it is expected to underestimate the reliability, and a RF model is required to obtain accurate results. 相似文献
13.
A. A. Alesheikh A. K. Oskouei F. Atabi H. Helali 《International Journal of Environmental Science and Technology》2005,2(2):133-140
Geographic information provides the basis for many types of decisions ranging from simple path finding, to the sustainable management of environmental conditions. Producing such information is a time consuming and costly endeavor. Data sharing on the web is an avenue to increase the efficiency of the practices. This paper scientifically examines the new emerging technologies namely, internet, geographic markup language (GML), and observation and measurement models, to construct an interoperable repository for air quality sensors measurements. The paper also elaborates on the design and implementation of a web-based air quality information system (AQIS) for the city of Tehran. In-situ sensors measure ozone (C3), carbon monoxide (CO), sulfur dioxide (SC2), nitrogen dioxide (NC2) and particulate matters (PM) in polluted metropolitans. Providing real-time air quality information can improve the decisions of the pertinent environmental organizations. Using GML for encoding sensors observations makes it possible to build an interoperable repository that is independent of platforms and vendors. Providing query possibilities based on monitoring stations, sensor names (pollutants), date and time intervals, and spatial query on the AQIS interfaces are the major functions of this system. Although standardized, it was concluded that the use of GML as data format increases the size of GML document. In addition, the developed system provides no map based results for the clients. Therefore, it is required to be improved by adding more GIS functions. 相似文献
14.
We developed an objective-based method for assessing environmental flows in estuaries; this method consists of two steps:
identifying ecological objectives with temporal–spatial variability and establishing a relationship between variations in
environmental factors and the alteration of freshwater inflows. Critical salinity and water depth requirements for different
species in special seasons in addition to temporal variation in natural river discharge were combined as objectives with spatial
and temporal variability. In a case study of the Yellow River Estuary, we determined that 15% and 101% of the natural river
discharge should be provided to ensure the minimum and maximum levels of environmental flows, respectively, for successful
integration of various objectives. Periods in early April, the end of June, August, and early October were identified as critical
for fulfilling reasonable water requirements. Although the recommended environmental flows may not be ideal for certain types
of species, they offer a boundary of environmental flows for preserving habitats and biodiversity in estuaries. 相似文献
15.
Soil erosion is a serious environmental and production problem in China. In particular, natural conditions and human impact have made the Chinese Loess Plateau particularly prone to intense soil erosion area. To decrease the risk on environmental impacts, there is an increasing demand for sound, and readily applicable techniques for soil conservation planning in this area. This work aims at the assessment of soil erosion and its spatial distribution in hilly Loess Plateau watershed (northwestern China) with a surface area of approximately 416.31 km2. This study was conducted at the Caijiamiao watershed to determine the erosion hazard in the area and target locations for appropriate initiation of conservation measures using the revised universal soil loss equation (RUSLE). The erosion factors of RUSLE were collected and processed through a geographic information system (GIS)-based approach. The soil erosion parameters were evaluated in different ways: The R-factor map was developed from the rainfall data, the K-factor map was obtained from the soil map, the C-factor map was generated based on Landsat-5 Thematic Mapper image and spectral mixture analysis, and a digital elevation model with a spatial resolution of 25 m was derived from topographic map at the scale of 1:50,000 to develop the LS-factor map. Support practice P factor was from terraces that exist on slopes where crops are grown. By integrating the six-factor maps in GIS through pixel-based computing, the spatial distribution of soil loss in the study area was obtained by the RUSLE model. The results showed that spatial average soil erosion at the watershed was 78.78 ton ha?1 year?1 in 2002 and 70.58 ton ha?1 year?1 in 2010, while the estimated sediment yield was found to be 327.96 × 104 and 293.85 × 104 ton, respectively. Soil erosion is serious, respectively, from 15 to 35 of slope degree, elevation area from 1,126 to 1,395 m, in the particular area of soil and water loss prevention. As far as land use is concerned, soil losses are highest in barren land and those in waste grassland areas are second. The results of the study provide useful information for decision maker and planners to take appropriate land management measures in the area. It thus indicates the RUSLE–GIS model is a useful tool for evaluating and mapping soil erosion quantitatively and spatially at a river watershed scale on a cell basis in Chinese Loess Plateau and for planning of conservation practices. 相似文献
16.
17.
生态功能优先背景下的西南岩溶区石漠化治理问题 总被引：12，自引：8，他引：4
文章分析了现有石漠化治理模式、物种选择、石漠化治理综合效益评估、消除贫困等方面存在的不足,并结合国家对西南岩溶石漠化区主体生态功能的定位,对未来石漠化治理过程中的几个关键问题进行了探讨,认为未来石漠化治理要更有效地兼顾生态与经济效益,提高生态补偿标准,完善生态补偿体制,促进石漠化区农村人口的城镇化转移,减少人口压力,消除农户破坏环境的驱动因素,促进石漠化治理成效的长期可持续发展,以保证西南岩溶石漠化区水土保持和生物多样性维护主体生态功能的实现。 相似文献
18.
C. Neuhold 《Natural Hazards》2013,65(3):2015-2030
Landfills are mainly located in lowland areas close to settlements inducing flood risk of potential environmental contamination and adverse health effects. During recent flood events, numerous landfill sites were reportedly exposed to inundations, leading to erosion of landfilled material and release of pollutants threatening humans and the environment. Although emissions from landfills under regular operating conditions are well investigated, the behaviour and associated emissions in case of flooding are widely unknown. To enable environmental risk management, flood-prone landfills must be identified to establish priorities for subsequent protection and mitigation measures. This paper presents two flood risk assessment approaches at different spatial scales: a macro-scale assessment approach (MaSA) and a micro-scale assessment approach (MiSA). Both methodologies aim to determine the proportion of landfills endangered by flooding, and evaluate the impacts. The latter are expressed by means of risk categories (minor to serious) of impacts that flooded sites might have on humans and the environment. The evaluation of 1,064 landfills in Austria based on MaSA yields roughly 30 % of landfills located within or close to flood risk zones. Material inventories of 147 sites exposed to flooding are established, and potential emissions during a flood event are estimated. Three representative case study areas are selected and investigated in detail by applying the MiSA approach based on 2D hydrodynamic models to calculate flow depths and shear stress and by developing emission scenarios to validate the macro-scale screening approach (MaSA). The applications of MiSA and MaSA outlines that hazardous emissions due to flooding can lead to significant impacts on the environment. Uncertainty associated with related processes and data sources is considerably high. Nevertheless, both MiSA and MaSA provide a decision support tool to identify landfills with imminent risk for humans and the environment. Therefore, the described methodologies provide toolsets to enable environmental risk reduction by applying a priority-ranked flood risk management. 相似文献
19.
Air pollution is usually driven by a complex combination of factors in which meteorology, physical obstacles, and interactions between pollutants play significant roles. Considering the characteristics of urban atmospheric pollution and its consequent impacts on human health and quality of life, forecasting models have emerged as an effective tool to identify and forecast air pollution episodes. The overall objective of the present work is to produce forecasts of pollutant concentrations with high spatio-temporal resolution and to quantify the uncertainty in those forecasts. Therefore, a new approach was developed based on a two-step methodology. Firstly, neural network models were used to generate short-term temporal forecasts based on air pollution and meteorology data. The accuracy of those forecasts was then evaluated against an independent set of historical data. Secondly, local conditional distributions of the observed values with respect to the predicted values were used to perform spatial stochastic simulations for the entire geographic area of interest. With this approach the spatio-temporal dispersion of a pollutant can be predicted, while accounting for both the temporal uncertainty in the forecast (reflecting the neural networks efficiency at each monitoring station) and the spatial uncertainty as revealed by the spatial variograms. Based on an analysis of the results, our proposed method offers a highly promising alternative for the characterization of urban air quality. 相似文献
20.
Dalia Bach Kirschbaum Robert Adler Yang Hong Sujay Kumar Christa Peters-Lidard Arthur Lerner-Lam 《Environmental Earth Sciences》2012,66(6):1683-1696
The increasing availability of remotely sensed data offers a new opportunity to address landslide hazard assessment at larger
spatial scales. A prototype global satellite-based landslide hazard algorithm has been developed to identify areas that may
experience landslide activity. This system combines a calculation of static landslide susceptibility with satellite-derived
rainfall estimates and uses a threshold approach to generate a set of ‘nowcasts’ that classify potentially hazardous areas.
A recent evaluation of this algorithm framework found that while this tool represents an important first step in larger-scale
near real-time landslide hazard assessment efforts, it requires several modifications before it can be fully realized as an
operational tool. This study draws upon a prior work’s recommendations to develop a new approach for considering landslide
susceptibility and hazard at the regional scale. This case study calculates a regional susceptibility map using remotely sensed
and in situ information and a database of landslides triggered by Hurricane Mitch in 1998 over four countries in Central America.
The susceptibility map is evaluated with a regional rainfall intensity–duration triggering threshold and results are compared
with the global algorithm framework for the same event. Evaluation of this regional system suggests that this empirically
based approach provides one plausible way to approach some of the data and resolution issues identified in the global assessment.
The presented methodology is straightforward to implement, improves upon the global approach, and allows for results to be
transferable between regions. The results also highlight several remaining challenges, including the empirical nature of the
algorithm framework and adequate information for algorithm validation. Conclusions suggest that integrating additional triggering
factors such as soil moisture may help to improve algorithm performance accuracy. The regional algorithm scenario represents
an important step forward in advancing regional and global-scale landslide hazard assessment. 相似文献