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1.
Collection of standardized assessment and monitoring data is critically important for supporting policy and management at local to continental scales. Remote sensing techniques, including image interpretation, have shown promise for collecting plant community composition and ground cover data efficiently. More work needs to be done, however, evaluating whether these techniques are sufficiently feasible, cost-effective, and repeatable to be applied in large programs. The goal of this study was to design and test an image-interpretation approach for collecting plant community composition and ground cover data appropriate for local and continental-scale assessment and monitoring of grassland, shrubland, savanna, and pasture ecosystems. We developed a geographic information system image-interpretation tool that uses points classified by experts to calibrate observers, including point-by-point training and quantitative quality control limits. To test this approach, field data and high-resolution imagery (∼3 cm ground sampling distance) were collected concurrently at 54 plots located around the USA. Seven observers with little prior experience used the system to classify 300 points in each plot into ten cover types (grass, shrub, soil, etc.). Good agreement among observers was achieved, with little detectable bias and low variability among observers (coefficient of variation in most plots <0.5). There was a predictable relationship between field and image-interpreter data (R 2 > 0.9), suggesting regression-based adjustments can be used to relate image and field data. This approach could extend the utility of expensive-to-collect field data by allowing it to serve as a validation data source for data collected via image interpretation.  相似文献   

2.
The future of the environment in China until the year 2050 has been forecasted through a heuristic approach. A questionnaire survey was given to a group of Japanese experts concerning 47 selected indices, including past data and reference data about other countries. The indices were related to aspects of the economy, population, food, energy, transportation, and the environment. The experts were requested to plot a graph for each index up to 2050 based on their intuition. The lines drawn by 60 experts were compiled along with their comments, and the characteristics of each index were analyzed. Different values for the indices regarding transportation and per capita GDP were forecasted by the experts, while rather similar values were obtained for those referencing population and food consumption. The respective fields of the experts were found to affect their perspectives on the future. Economists tended to show rather optimistic views, expressing a business-as-usual scenario, while engineers predicted limited growth but technological innovation.  相似文献   

3.
提出了灰色系统模型GM(1,1)参数优化估计的一种新方法--加速遗传算法,分析了该算法控制参数的优化特性,总结了这些参数的简便设置技术,并给出了它的几个应用实例,该方法也可用于其它环境工程优化计算中。  相似文献   

4.
This research was to evaluate the Technical Guideline (HJ/T130-2003) effectiveness based on data resource from a questionnaire survey and interviews on EIA experts. The result demonstrated that the guideline served mainly as a quality control measure for PEIA products, and only a small proportion of experts considered it effective due to its inconsistency with the newly released Chinese PEIA Regulation (2009) and poor practicability. Current status of SEA implementation in China was also studied in terms of application fields, effectiveness evaluation, and major issues to affect SEA, to conclude that SEA implementation in China is premature, and with limited effectiveness. The major problem was the lack of effective methodologies and technical tools. Recommendations for revising the PEIA Guideline and advices to improving SEA implementation in China were accordingly proposed.  相似文献   

5.
Data from over 2000 stations and knowledge from experts on atmospheric transport, soil geochemistry, lake chemistry, wetland processes and acidification modelling were assembled in an expert system. The data were grouped by aggregates of tertiary watersheds based on water chemistry knowledge. A set of expert rules was used to determine which of six existing models was most appropriate for a given set of data. Comparison of computed and observed alkalinity indicated median relative errors from 11.3–17.9%, with regression slopes ranging from 0.91–1.18 and regression coefficients between 0.82 and 0.99. The expert model performance was further confirmed with paleolimnological data and other independent sets of data. The sensitivity of the predicted alkalinity was illustrated by changing some of the rules. Given that the rules were acceptable by experts and produced reasonable agreement with observations, the knowledge-based system seemed a viable approach to the impact assessment of acidic deposition.  相似文献   

6.
This research was to evaluate the Technical Guideline (HJ/T130-2003) effectiveness based on data resource from a questionnaire survey and interviews on EIA experts. The result demonstrated that the guideline served mainly as a quality control measure for PEIA products, and only a small proportion of experts considered it effective due to its inconsistency with the newly released Chinese PEIA Regulation (2009) and poor practicability. Current status of SEA implementation in China was also studied in terms of application fields, effectiveness evaluation, and major issues to affect SEA, to conclude that SEA implementation in China is premature, and with limited effectiveness. The major problem was the lack of effective methodologies and technical tools. Recommendations for revising the PEIA Guideline and advices to improving SEA implementation in China were accordingly proposed.  相似文献   

7.
Remote cameras are an increasingly important tool for ecological research. While remote camera traps collect field data with minimal human attention, the images they collect require post-processing and characterization before it can be ecologically and statistically analyzed, requiring the input of substantial time and money from researchers. The need for post-processing is due, in part, to a high incidence of non-target images. We developed a stand-alone semi-automated computer program to aid in image processing, categorization, and data reduction by employing background subtraction and histogram rules. Unlike previous work that uses video as input, our program uses still camera trap images. The program was developed for an ungulate fence crossing project and tested against an image dataset which had been previously processed by a human operator. Our program placed images into categories representing the confidence of a particular sequence of images containing a fence crossing event. This resulted in a reduction of 54.8% of images that required further human operator characterization while retaining 72.6% of the known fence crossing events. This program can provide researchers using remote camera data the ability to reduce the time and cost required for image post-processing and characterization. Further, we discuss how this procedure might be generalized to situations not specifically related to animal use of linear features.  相似文献   

8.
This paper introduces a new approach to prioritize urban planning projects according to their environmental pressure in an efficient and reliable way. It is based on the combination of three procedures: (i) the use of environmental pressure indicators, (ii) the aggregation of the indicators in an Environmental Pressure Index by means of the Analytic Network Process method (ANP) and (iii) the interpretation of the information obtained from the experts during the decision-making process.The method has been applied to a proposal for urban development of La Carlota airport in Caracas (Venezuela). There are three options which are currently under evaluation. They include a Health Club, a Residential Area and a Theme Park. After a selection process the experts chose the following environmental pressure indicators as ANP criteria for the project life cycle: used land area, population density, energy consumption, water consumption and waste generation. By using goal-oriented questionnaires designed by the authors, the experts determined the importance of the criteria, the relationships among criteria, and the relationships between the criteria and the urban development alternatives.The resulting data showed that water consumption is the most important environmental pressure factor, and the Theme Park project is by far the urban development alternative which exerts the least environmental pressure on the area. The participating experts coincided in appreciating the technique proposed in this paper is useful and, for ranking ordering these alternatives, an improvement from traditional techniques such as environmental impact studies, life-cycle analysis, etc.  相似文献   

9.
基于环境质量监测的区域环境质量综合评价体系   总被引:1,自引:0,他引:1  
环境质量的优劣直接关系到人类的生存和发展,如何对某一区域环境质量进行科学的综合评价对环境管理具有重要的理论和现实意义。根据环境质量评价指标的选择原则,以环境质量监测为基础,通过征求专家意见确定了能反映区域环境质量特性的指标及其权重,建立了区域环境质量的综合评价体系。并用此综合评价体系对四川省6个地区的环境质量进行了评价,计算了区域环境质量综合指数,结果表明,该评价体系简单、方便、适用性强且易于操作,为科学地评价和考核区域环境质量提供研究方法。  相似文献   

10.
基于Windows Mobile技术的环境监测数据外业采集系统研   总被引:1,自引:0,他引:1  
研究了Windows Mobile智能手机平台上环境监测数据外业采集系统框架,以SQL Server Compact3.5数据库技术存储、管理现场监测数据,通过SQL Server复制技术将数据汇交到监测站的中心数据库中。提出了综合场景信息与业务因子监测数据同步(准同步)采集、一体化管理、关联分析、复合应用的集成应用思路。举例展示了系统配置和软件代码实现。  相似文献   

11.
Gas chromatography-mass spectrometry (GC-MS) has played a pivotal role in the discovery of disinfection by-products (DBPs) in drinking water. DBPs are formed when disinfectants, such as chlorine, ozone, chlorine dioxide or chloramine, react with natural organic matter in the water. The first DBP known--chloroform--was identified by Rook in 1974 using GC-MS. Soon thereafter, chloroform and other trihalomethanes were found to be ubiquitous in chlorinated drinking water. In 1976, the National Cancer Institute published results linking chloroform to cancer in laboratory animals, and an important public health issue was born. Mass spectrometry and, specifically, GC-MS became the key tool used for measuring these DBPs in water and for discovering other DBPs that were formed. Over the last 25 years, hundreds of DBPs have been identified, mostly through the use of GC-MS, which has spawned additional health effects studies and regulations. Early on, GC with low resolution electron ionization (EI)-MS was used, together with confirmation with chemical standards, for identification work. Later, researchers utilized chemical ionization (CI)-MS to provide molecular weight information and high resolution El-MS to aid in the determination of empirical formulae for the molecular ions and fragments. More recently, liquid chromatography-mass spectrometry (LC-MS) with either electrospray ionization (ESI) or atmospheric pressure chemical ionization (APCI) has been used to try to uncover highly polar DBPs that most experts believe have been missed by earlier GC-MS studies. Despite 25 years of research in the identification of new DBPs, new ones are being discovered every year, even for chlorine which has been the most extensively studied.  相似文献   

12.
This paper presents a mathematical model of local pollutant dispersion designed to compute the concentration field above and around the Marcoule nuclear site. The model is based on integrating the classical turbulent diffusion equation, corrected (prior to integration) by experimental wind tunnel data obtained for a scaled-down model of the site. The computed results are compared with full-scale experimental observations at Marcoule in the case of neutral atmosphere. A comparison with the standard Gaussian model is also made. Finally, a critical analysis of the model is presented. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

13.
In this study we used photographs of tree crowns to test whether the assessment methods for tree defoliation in Switzerland have changed over time. We randomly selected 24 series of slides of Norway spruce with field assessments made between 1986 and 1995. The slides were randomly arranged and assessed by three experts without prior knowledge of the year when the slide was taken or the tree number. Defoliation was assessed using the Swiss reference photo guide. Although the correlations between the field assessments and slide assessments were high (Spearman's rank correlation coefficient ranged between 0.79 and 0.83), we found significant differences between field and slide assessments (4.3 to 9% underprediction by the slide assessors) and between the slide assessments. However, no significant trends in field assessment methods could be detected. When the mean differences between field and slide assessments were subtracted, in some years, field assessors consistently underpredicted (1990, 1992) or overpredicted defoliation (1987, 1991). Defoliation tended to be overpredicted in slides taken against the light, and underpredicted for trees with more than 25% crown overlap. We conclude that slide series can be used to detect changes in assessment methods. However, potential observer bias calls for more objective methods of assessment.  相似文献   

14.
综述了土壤重金属污染空间插值方法研究现状,分析了3类典型的插值方法(确定性插值方法、地统计学插值方法和组合插值方法),以及2种常用的精度验证方法(交叉验证法和独立的数据集验证法)各自的优缺点与适用范围,提出了加强组合插值模型优化与精度提升、利用计算机智能技术优化插值算法模型、开发针对土壤重金属领域的考虑空间插值软数据挖...  相似文献   

15.
Environmental impact evaluation is an essential component in environmental impact assessment (EIA) study for any developmental project, wherein importance assignment to various parameters depends on human judgement/experts opinion, which involves a high order of subjectivity. In order to minimise bias and subjectivity in evaluation of impacts, and hence in decision making, three different methods, viz. Battelle environmental evaluation system (BEES), importance scale matrix (ISM), and a combination of both, are considered in the present study. A case study for a development project (setting up a new industry) in an industrial belt situated in a region, which is rich in biological resources with good agricultural productivity and having high potential for further industrial development, is presented. The results of the other two methods are compared with the widely used method of BEES. Both methods are found comparable to the BEES method. However, it is observed that the ISM approach provides a better tool for reducing bias and subjectivity occurring in human judgement.  相似文献   

16.
This study aims to study the distribution of contaminants in rivers that flow into the Caribbean Sea using chlorophyll-a (Chl-a) and suspended sediment (SS) as markers and ALOS AVNIR-2 satellite sensor data. The Haina River (HN) and Ozama and Isabela Rivers (OZ-IS) that flow through the city of Santo Domingo, the capital of the Dominican Republic, were chosen. First, in situ spectral reflectance/Chl-a and SS datasets obtained from these rivers were acquired in March 2011 (case A: with no rain influence) and June 2011 (case B: with rain influence), and the estimation algorithm of Chl-a and SS using AVNIR-2 data was developed from the datasets. Moreover, the developed algorithm was applied to AVNIR-2 data in November 2010 for case A and August 2010 for case B. Results revealed that for Chl-a and SS estimations under cases A and B conditions, the reflectance ratio of AVNIR-2 band 4 and band 3 (AV4/AV3) and the reflectance of AVNIR-2 band 4 (AV4) were effective. The Chl-a and SS mapping results obtained using AVNIR-2 data corresponded with the field survey results. Finally, an outline of the distribution of contaminants at the mouth of the river that flows into the Caribbean Sea was obtained for both rivers in cases A and B.  相似文献   

17.
The evaluation of the status of a municipal drinking water treatment plant (WTP) is important. The evaluation depends on several factors, including, human health risks from disinfection by-products (R), disinfection performance (D), and cost (C) of water production and distribution. The Dempster–Shafer theory (DST) of evidence can combine the individual status with respect to R, D, and C to generate a new indicator, from which the overall status of a WTP can be evaluated. In the DST, the ranges of different factors affecting the overall status are divided into several segments. The basic probability assignments (BPA) for each segment of these factors are provided by multiple experts, which are then combined to obtain the overall status. In assigning the BPA, the experts use their individual judgments, which can impart subjective biases in the overall evaluation. In this research, an approach has been introduced to avoid the assignment of subjective BPA. The factors contributing to the overall status were characterized using the probability density functions (PDF). The cumulative probabilities for different segments of these factors were determined from the cumulative density function, which were then assigned as the BPA for these factors. A case study is presented to demonstrate the application of PDF in DST to evaluate a WTP, leading to the selection of the required level of upgradation for the WTP.  相似文献   

18.
NOAA/AVHRR数据在植被生态环境监测中的应用探讨   总被引:3,自引:0,他引:3  
沈志 《干旱环境监测》1997,11(2):98-103
介绍了NOAA/AVHRR数据的特点。对利用NOAA/AVHRR数据进行植被生态监测的原理及方法进行了探讨。并对该领域的最新成果及应用前景给予了论述,提出在新疆荒漠区进行监测的步骤和可能性。  相似文献   

19.
In this study, we present the digital evaluation of Landsat TM data and field spectral measurements for retrieving chlorophyll-a (chl-a) concentration and trophic state index in Lake Chagan of Northeast China. Chl-a concentration of the lake can be estimated from the band ratio (TM4/TM3) and the field spectral data at 670 nm (absorption peak) and at 700 nm (reflectance peak). The results show that the best determination coefficient (R 2) is 0.67 from the TM data, by which chl-a distribution can be mapped. Based on chl-a determination from laboratory analysis, field spectral and TM data, the modified trophic state index (TSIM) was applied to assess the lake’s trophic state. With the available data in Lake Chagan, each algorithm demonstrates the similar result for assessing the lake’s chl-a and trophic state. Our results indicate that Landsat TM and field spectral data could be used effectively to determine chl-a concentration and evaluate the trophic state of Lake Chagan in the study.  相似文献   

20.
Small islands have the attention of the international community because they are territories with unique features, and a pressing need for the enhancement of sustainability. Strategic Environmental Assessment (SEA) has characteristics that may promote the development and improvement of sustainability in these territories: (i) changing the mind-set, and the decision-making and institutional paradigm, (ii) facilitating cooperation and coordination between different stakeholders, and (iii) providing a framework for good governance and community empowerment. The scientific literature suggests that there may be a need for context-specific SEA in these territories. However, SEA studies often do not incorporate local contextual information, including intuitive knowledge and sense of place. Therefore, there is a possible gap between what is found in the literature and what local communities think, including different stakeholders and experts. Hence, the main goal of this research was to gain an insight into the views and perspectives of small islands SEA experts about issues related to SEA in European small islands, including context-specific approaches, as well as the contribution of SEA for sustainability in these territories. To achieve the research aim, exploratory research using a questionnaire-based survey was designed, aimed at experts on SEA in European small islands. Findings showed regional cooperation networks may have a fundamental role when developing SEA-specific approaches in these territories. This is because SEA-specific approaches encourage a joint effort among islands within one region to improve SEA capacity-building, develop and share a baseline information system, and to share and exchange resources, overall. Also, guidelines are preferred among experts over more legal frameworks and regulations. Finally, the research showed that experts view SEA as a way to enhance sustainability in small islands. This study highlights the importance of integrating stakeholders, such as territorial experts, to learn and promote the use and improvement of environmental and sustainability tools such as SEA.  相似文献   

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