The Experts below are selected from a list of 708 Experts worldwide ranked by ideXlab platform

P Mcdonald - One of the best experts on this subject based on the ideXlab platform.

  • mapping intertidal estuarine sediment grain size distributions through Airborne remote sensing
    Remote Sensing of Environment, 2003
    Co-Authors: Michael P Rainey, Andrew N Tyler, David Gilvear, Robert G Bryant, P Mcdonald
    Abstract:

    Abstract The intertidal environments of estuaries represent critical exchange environments of sediment and sediment bound contaminants. Ecological and sedimentological related investigations of these environments require monitoring methods that provide rapid spatially representative data on sediment grain size distribution. Remote sensing has the potential to provide synoptic information of intertidal environments. Previous in situ and laboratory-based reflectance investigations have demonstrated that for effective quantification of sediment grain size distributions, remote sensing platforms must include measurements within the short-wave infrared (SWIR). In addition, the timing of image acquisition, in relation to tidal cycles and sediment moisture content, is critical in optimising the spectral differences between the coarser sand and finer ‘mud’ fraction of sediments. Daedalus 1268 Airborne Thematic Mapper (ATM) has been identified as an appropriate platform and sensor for providing accurate synoptic maps of estuarine sediment distributions. This paper presents the results from the application of ATM 1.75 m resolution data to the mapping of surface sediment grain-size distributions across intertidal areas of Ribble Estuary, Lancashire, UK. ATM imagery was acquired after the intertidal area was exposed to strong summer drying conditions. Pre-processing and linear unmixing of the imagery collected of the intertidal zone following a period of drying allowed accurate sub-pixel determinations (1.75 m resolution) of sediment clay (r2=0.79) but less accurate for sand (r2=0.60). The results also demonstrate deterioration in the image calibration with increasing sediment moisture content and microphytobenthos cover. However, recombining the subpixel end member abundances through multivariate regression analysis improved the image calibration significantly for both sediment clay and sand content (r2>0.8) for imagery collected in both dryer and wetter conditions. These results demonstrate that ATM data, or similar, can be used to gain quantitative information on intertidal sediment distributions and such data has application to a wide variety of estuarine research.

  • The Influence of Surface and Interstitial Moisture on the Spectral Characteristics of Intertidal Sediments: Implications for Airborne Image Acquisition and Processing
    2000
    Co-Authors: M. P. Rainey, David Gilvear, A. N. Tyler, R. G. Bryant, P Mcdonald
    Abstract:

    Intertidal sediment distribution is an important factor in the understanding of estuarine ecological, morphological and pollution processes. Airborne remote sensing is identified as a cost-effective tool that may be used to provide accurate synoptic maps of estuarine sediment distributions. However, prior to the collection and analysis of Airborne imagery, spectral characterization of intertidal sediments is fundamental. Through a series of in situ and laboratory reflectance (0.35--2.5 mm) experiments the spectral complexity of the Ribble Estuary, UK, intertidal sediments has been investigated. Positive relationships between Daedalus Airborne Thematic Mapper band 9 and band 10 simulated reflectance and percentage sand of intertidal sediments have been identified in the field (r2 5 0.51 and r2 5 0.61 )

Michael P Rainey - One of the best experts on this subject based on the ideXlab platform.

  • mapping intertidal estuarine sediment grain size distributions through Airborne remote sensing
    Remote Sensing of Environment, 2003
    Co-Authors: Michael P Rainey, Andrew N Tyler, David Gilvear, Robert G Bryant, P Mcdonald
    Abstract:

    Abstract The intertidal environments of estuaries represent critical exchange environments of sediment and sediment bound contaminants. Ecological and sedimentological related investigations of these environments require monitoring methods that provide rapid spatially representative data on sediment grain size distribution. Remote sensing has the potential to provide synoptic information of intertidal environments. Previous in situ and laboratory-based reflectance investigations have demonstrated that for effective quantification of sediment grain size distributions, remote sensing platforms must include measurements within the short-wave infrared (SWIR). In addition, the timing of image acquisition, in relation to tidal cycles and sediment moisture content, is critical in optimising the spectral differences between the coarser sand and finer ‘mud’ fraction of sediments. Daedalus 1268 Airborne Thematic Mapper (ATM) has been identified as an appropriate platform and sensor for providing accurate synoptic maps of estuarine sediment distributions. This paper presents the results from the application of ATM 1.75 m resolution data to the mapping of surface sediment grain-size distributions across intertidal areas of Ribble Estuary, Lancashire, UK. ATM imagery was acquired after the intertidal area was exposed to strong summer drying conditions. Pre-processing and linear unmixing of the imagery collected of the intertidal zone following a period of drying allowed accurate sub-pixel determinations (1.75 m resolution) of sediment clay (r2=0.79) but less accurate for sand (r2=0.60). The results also demonstrate deterioration in the image calibration with increasing sediment moisture content and microphytobenthos cover. However, recombining the subpixel end member abundances through multivariate regression analysis improved the image calibration significantly for both sediment clay and sand content (r2>0.8) for imagery collected in both dryer and wetter conditions. These results demonstrate that ATM data, or similar, can be used to gain quantitative information on intertidal sediment distributions and such data has application to a wide variety of estuarine research.

Alistair Watson - One of the best experts on this subject based on the ideXlab platform.

  • spatial variability in soil moisture as predicted from Airborne Thematic Mapper atm data
    Earth Surface Processes and Landforms, 1995
    Co-Authors: Donald A Davidson, Alistair Watson
    Abstract:

    In the first part of this project, the extent to which moisture content of alluvial soils could be predicted from imagery derived from an Airborne Thematic Mapper (ATM) was investigated. From sampling done on the same day as the flight, it was found that digital numbers derived from the thermal channel (waveband 11) were strongly correlated with gravimetric moisture content. From sampling three fields of contrasting land cover, the relationship between waveband 11 values and moisture content was found to be independent of land cover type. Spatial variation in waveband 11 values and thus moisture content were related to palaeochannel patterns on the alluvial land. This was investigated by deriving variograms for long transects from each of the three investigated fields. The range and sills of the variograms are shown to express the nature and pattern of palaeochannels. By the application of such geostatistical techniques, high resolution imagery can thus be used to quantify palaeochannel characteristics on alluvial land.

David Gilvear - One of the best experts on this subject based on the ideXlab platform.

  • mapping intertidal estuarine sediment grain size distributions through Airborne remote sensing
    Remote Sensing of Environment, 2003
    Co-Authors: Michael P Rainey, Andrew N Tyler, David Gilvear, Robert G Bryant, P Mcdonald
    Abstract:

    Abstract The intertidal environments of estuaries represent critical exchange environments of sediment and sediment bound contaminants. Ecological and sedimentological related investigations of these environments require monitoring methods that provide rapid spatially representative data on sediment grain size distribution. Remote sensing has the potential to provide synoptic information of intertidal environments. Previous in situ and laboratory-based reflectance investigations have demonstrated that for effective quantification of sediment grain size distributions, remote sensing platforms must include measurements within the short-wave infrared (SWIR). In addition, the timing of image acquisition, in relation to tidal cycles and sediment moisture content, is critical in optimising the spectral differences between the coarser sand and finer ‘mud’ fraction of sediments. Daedalus 1268 Airborne Thematic Mapper (ATM) has been identified as an appropriate platform and sensor for providing accurate synoptic maps of estuarine sediment distributions. This paper presents the results from the application of ATM 1.75 m resolution data to the mapping of surface sediment grain-size distributions across intertidal areas of Ribble Estuary, Lancashire, UK. ATM imagery was acquired after the intertidal area was exposed to strong summer drying conditions. Pre-processing and linear unmixing of the imagery collected of the intertidal zone following a period of drying allowed accurate sub-pixel determinations (1.75 m resolution) of sediment clay (r2=0.79) but less accurate for sand (r2=0.60). The results also demonstrate deterioration in the image calibration with increasing sediment moisture content and microphytobenthos cover. However, recombining the subpixel end member abundances through multivariate regression analysis improved the image calibration significantly for both sediment clay and sand content (r2>0.8) for imagery collected in both dryer and wetter conditions. These results demonstrate that ATM data, or similar, can be used to gain quantitative information on intertidal sediment distributions and such data has application to a wide variety of estuarine research.

  • The Influence of Surface and Interstitial Moisture on the Spectral Characteristics of Intertidal Sediments: Implications for Airborne Image Acquisition and Processing
    2000
    Co-Authors: M. P. Rainey, David Gilvear, A. N. Tyler, R. G. Bryant, P Mcdonald
    Abstract:

    Intertidal sediment distribution is an important factor in the understanding of estuarine ecological, morphological and pollution processes. Airborne remote sensing is identified as a cost-effective tool that may be used to provide accurate synoptic maps of estuarine sediment distributions. However, prior to the collection and analysis of Airborne imagery, spectral characterization of intertidal sediments is fundamental. Through a series of in situ and laboratory reflectance (0.35--2.5 mm) experiments the spectral complexity of the Ribble Estuary, UK, intertidal sediments has been investigated. Positive relationships between Daedalus Airborne Thematic Mapper band 9 and band 10 simulated reflectance and percentage sand of intertidal sediments have been identified in the field (r2 5 0.51 and r2 5 0.61 )

Robert G Bryant - One of the best experts on this subject based on the ideXlab platform.

  • mapping intertidal estuarine sediment grain size distributions through Airborne remote sensing
    Remote Sensing of Environment, 2003
    Co-Authors: Michael P Rainey, Andrew N Tyler, David Gilvear, Robert G Bryant, P Mcdonald
    Abstract:

    Abstract The intertidal environments of estuaries represent critical exchange environments of sediment and sediment bound contaminants. Ecological and sedimentological related investigations of these environments require monitoring methods that provide rapid spatially representative data on sediment grain size distribution. Remote sensing has the potential to provide synoptic information of intertidal environments. Previous in situ and laboratory-based reflectance investigations have demonstrated that for effective quantification of sediment grain size distributions, remote sensing platforms must include measurements within the short-wave infrared (SWIR). In addition, the timing of image acquisition, in relation to tidal cycles and sediment moisture content, is critical in optimising the spectral differences between the coarser sand and finer ‘mud’ fraction of sediments. Daedalus 1268 Airborne Thematic Mapper (ATM) has been identified as an appropriate platform and sensor for providing accurate synoptic maps of estuarine sediment distributions. This paper presents the results from the application of ATM 1.75 m resolution data to the mapping of surface sediment grain-size distributions across intertidal areas of Ribble Estuary, Lancashire, UK. ATM imagery was acquired after the intertidal area was exposed to strong summer drying conditions. Pre-processing and linear unmixing of the imagery collected of the intertidal zone following a period of drying allowed accurate sub-pixel determinations (1.75 m resolution) of sediment clay (r2=0.79) but less accurate for sand (r2=0.60). The results also demonstrate deterioration in the image calibration with increasing sediment moisture content and microphytobenthos cover. However, recombining the subpixel end member abundances through multivariate regression analysis improved the image calibration significantly for both sediment clay and sand content (r2>0.8) for imagery collected in both dryer and wetter conditions. These results demonstrate that ATM data, or similar, can be used to gain quantitative information on intertidal sediment distributions and such data has application to a wide variety of estuarine research.