Remote Sensing of Seagrass Ecosystems: Use of Spaceborne and Airborne Sensors

Effect of oyster aquaculture on seagrass Zostera marina at the estuarine landscape scale in Willapa Bay, Washington (USA)

“…There has been an extensive amount of effort devoted to using remote sensing to understand seagrass dynamics at larger estuarine landscape scales, particularly in estuaries where other anthropogenic disturbances such as eutrophication are more likely to affect change (Kendrick et al 2000, Dekker et al 2007, Orth et al 2010b, Lyons et al 2013), but only recently have investigators addressed impacts of shellfish aquaculture on seagrass at this scale (Ward et al 2003, Carswell et al 2006, Barille et al 2010, Martin et al 2010, Bulmer et al 2012. Willapa Bay provides a unique opportunity to examine this interaction at the estuarine landscape scale because shellfish aquaculture within eelgrass was not restricted prior to 2007 when a new permit (US Nationwide Permit 48) was issued by the US Army Corps of Engineers (US ACOE) with protection for native eelgrass Z. marina.…”

Supervised Classification of Benthic Reflectance in Shallow Subtropical Waters Using a Generalized Pixel-Based Classifier across a Time Series

“…Given the relatively low spectral response that reaches remote sensors from underwater subjects [11] and the objective of utilizing the image-based classifier across images, pre-processing of satellite data to adequately correct for atmospheric and water column variation was an important step of this study. The underlying motivation of working towards a mapping methodology that is easily implemented with a minimum of specialized equipment and software influenced the decisions on pre-processing techniques.…”

“…Continued study of coastal landscape dynamics with accurate, quantitative measurements of areal extent and density of seagrasses is needed to better understand the mosaic of their distribution (degree of patchiness, gap dynamics, habitat edge type, and connectivity) in conjunction with the temporal and spatial variability of hydrologic inputs to coastal areas [7]. Characterizing these dynamics from a synoptic, repeatable perspective with remotely sensed data [11] can strongly augment more accurate point measures of change derived in-situ [12].…”

“…The "quality" and relevance of classes derived from satellite data are variable across images [21] so that transferring pixel-based definitions of class spectra to other images has been considered impractical [11]. Constraining class definitions to the image in which training pixels are identified, however, limits the resulting multi-temporal analysis to dates where in-situ or other ground truth source is available for the selection of calibration data.…”

Guest Editorial: Coastal Aquatic Remote Sensing Applications for Environmental Monitoring and Management

“…Very few papers, with the exception of large scale physical-biological oceanographic applications, published in scientific journals show a global uptake of the science and techniques of aquatic remote sensing into environmentally relevant monitoring and management applications. The majority of past reviews of remote sensing for coastal applications have focused on two areas: (1) improvements to technology, techniques and applications, with limited assessment of accuracy and true costs [1,3,[5][6][7][8][9][10][11] and (2) understanding light interactions in shallow water environments [6,12]. Both of these activities were essential to underpin the use of remote sensing for monitoring and managing coastal resources.…”