Can Coral Reefs Be Monitored from Space?

Remote sensing: ecology

“…Imagery from IKONOS and similar sensors can be acquired over large, inaccessible areas and, significantly, has a very high level of spatial detail (AndrÇfouât et al, 2003). Various different classification schemes have been used to map coral reefs (e.g., Hochberg and Atkinson, 2003;Capolsini et al, 2003), and other investigations have monitored change in coral reef communities over time (Philipson and Lindell, 2003;Palandro et al, 2003a). For instance, Palandro et al (2003b) used archive Landsat TM and ETMϩ imagery to demonstrate the significant loss of coral reef in the Florida Keys since 1984.…”

Mapping and monitoring intertidal benthic habitats: a review of techniques and a proposal for a new visual methodology for the European coasts

“…Moreover, satellite imagery resolution is often too coarse (eg, 10-20 m, SPOT; 15-30 m Landsat TM) for site-specifi c mapping of intertidal environments due to potential habitat patchiness, and satellites are thus more appropriate for mapping general land-cover type (eg, vegetated versus unvegetated, reef versus nonreef) (Higinbotham et al, 2004;Zharikov et al, 2005). Finally, even for structured habitats such as coral reefs, a greater number of narrower spectral bands is still required to be able to separate reef species or to differentiate between parameters visible in the fi eld such as dead corals invaded by algae versus living corals (Philipson and Lindell, 2003).…”

“…Moreover, as underlined by several authors (eg, Kvernevik et al, 2002), most of the methods used to map seafl oors are expensive with respect to both time and money. Consequently, few long-term monitoring methods exist in the marine environment beyond those pertaining to 'structured habitats' such as coral reefs or mangroves in tropical areas (Green et al, 1996;Chauvaud et al, 1998;Holden and Le Drew, 1998;Manson et al, 2003;Philipson and Lindell, 2003;Proisy et al, 2007) and seagrass beds in temperate or tropical areas (Larkum et al, 2006;Orth et al, 2006;Wabnitz et al, 2008), for which the long-term spatiotemporal dynamics can be monitored by remote sensing methods (eg, Godet et al, 2008). The study of spatiotemporal dynamics of such habitats is very useful as potential ecological indicators, but, by defi nition, global changes affect all marine benthic species and habitats, including common and widespread species and habitats (Edwards and Richardson, 2004).…”

Application of Remote Sensing in Natural Sciences

“…In general, remote sensing is "the measurement or acquisition of information about the properties of an object or phenomenon by a recording device (sensor: satellite or aircraft) that is not studied in physical or direct contact with the phenomenon" [5]. Integrated use of remote sensing data, GPS and GIS enables consultants, natural resource managers and researchers in government agencies, conservation organizations and industry to develop management plans for a variety of natural resource management programs [6]. When natural resources are identified using remote sensing data, sampling strategies are also used to collect and evaluate field observations of the variables at the selected locations [7].…”