Agricultural Development and Environmental Research American and Czechoslovak Perspectives: Proceedings of a Bilateral Workshop (1987) / Chapter Skim
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'SCIENTIFIC TOOLS FOR ENVIRONMENTAL MONITORING'
'SCIENTIFIC TOOLS FOR ENVIRONMENTAL MONITORING'
Pages 44-58
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From page 44... ...
The term remote sensing as applied to environmental monitoring means simply the acquisition of environmental information without physical contact between the measured feature or parameter and the measurement sensor. There are obviously trade-offs to consider in selecting a measurement and monitoring system -- traditional point monitoring techniques or remote sensing -- including the quality of information and the cost of obtaining that information.
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From page 45... ...
Nevertheless, photography continues to be the primary remote sensing technique due to several factors: the well-developed techniques, materials, and equipment; the tremendous information content of an individual image; and the ease of interpretation of data. Also, photography often serves to complement in situ measurement data.
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From page 46... ...
Active Remote Sensing Systems Table 3 summarizes the scattering and absorption processes employed in laser systems and indicates the remote measurement
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From page 47... ...
The design concept and selected practical environmental measurement applications for two of these remote sensing instruments -- the lidar and the laser fluorosensor -- are discussed below. In addition, Figure 1 shows the absorption features of many pollutant gases over the region of < 1 - 15 um (Yates and Taylor 1960)
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From page 48... ...
With a laser pulse width of 20 nsec, a maximum vertical resolution of 3 m is likewise obtainable although the signal is usually digitized to yield a resolution of 6 m. Some of the typical applications of lidars are: • Determining the space and time variability of aerosol inhomogeneities; • Assessing relative particulate concentrations; • Measuring the vertical growth of boundary layers; • Providing input to complex terrain and other atmospheric dispersion modeling efforts; • Measuring plume opacity;
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From page 49... ...
Subsequently, developmental efforts were directed at a number of other water quality parameters. Operational airborne systems are hi use by a number of research centers including the Environmental Monitoring Systems Laboratory in Las Vegas, Nevada; the Canadian Center for Remote Sensing in Ontario, Canada; the University of Oldenburg, FRG; and the National Aeronautics and Space
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From page 50... ...
Several applications for laser fluorosensor systems are: • Optical attenuation coefficient measurements; • Observations of the mixing and interfacing of marine and fresh waters; • Locating, mapping, and fingerprinting petrochemical spills and discharges; • Assessing the relative contribution of point and non-point source pollution to receiving waters; • Flow, dispersion, and mixing studies using fluorescent dyes; • Bathymetry; • Column or range-resolved concentration measurements of algal pigments; • Estimating acidification parameters in surface waters, e.g., pH, [Al]
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From page 51... ...
GEOGRAPHIC INFORMATION SYSTEMS (GIS) A primary characteristic of monitoring networks and particularly remote sensing systems is that they produce a vast amount of spatially related data.
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From page 52... ...
A demonstration of the use of a GIS was recently completed for a hazardous waste area in the San Gabriel Basin in southern California (Fenstermaker and Duggan 1986)
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From page 53... ...
The application of this technology to other interest areas such as land and resource management, urban development, marketing, and traffic planning can be readily envisioned. A partial listing of the requirements for such endeavors could include some of the following data types: Flora and Fauna Critical Habitats Threatened/Endangered Species Soil Porosity Soil Morphology Mineral Composition Moisture Content Texture Aquifer Extent Depth to Aquifer Zone of Recharge Flow Rate/Direction Hydraulic Conductivity Permeability Groundwater Quality Meteorology/Climatology • Dissolved Organics • Precipitation Record • pH • Temperature • Salinity • Wind Speed/Direction
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From page 54... ...
A pre-qualification phase of the program involves an evaluation of the capabilities of the various laboratories to analyze the study analytes in a number of matrices. A number of performance evaluation materials (PEMs)
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From page 55... ...
A 10 percent qualitative scoring was arbitrarily selected for the proper identification of all of the analytes, and 90 percent of the overall score was reserved for the quantitative results. Prediction intervals are used by EPA to establish analytical acceptance windows in its Waste Water and Water Quality Programs
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From page 56... ...
A properly designed quality assurance program includes the identification and quantification of all sources of error associated with each step of the environmental monitoring task so that the resulting data will be of known quality. The components of error, or variance, include those associated with sampling, sample preparation, and analysis.
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From page 57... ...
J Remote Sensing.
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From page 58... ...
1985. Airborne lidar tracking of fluorescent tracers for atmospheric transport and diffusion studies.
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