In our proposed integration framework, the reef system under investigation is:
• segmented into biogeochemically distinct geomorphological structural zones
based on moderate spatial resolution multispectral satellite imaging
• establishment of time-space patterns of light and nutrients for the reef zones
(defined by the initial landscape segmentation) based on benthic landscape
irradiance and hydrodynamic models driven by low spatial - high temporal
resolution oceanographic and meteorological satellite sensors
• mapping of spatial distributions of intra-zone biotopes using high spatial
resolution airborne or satellite-borne sensors
• measurement of in situ process to determine benthic community metabolic
functions for the recognized biotopes
Guided by the regional distributions of environmental conditions modeled through
indirect remote sensing and the reef zone biotope maps obtained by mapping with high
resolution sensors, the spatially-distributed mixed community P g , R, E, and G for the
selected reef zone is calculated for a predetermined time increment. Iteration over time
increments and then over reef zones, followed by time and space integration, results in
seasonal or annual estimates of reef system E and G.
3.1 REMOTE SENSING OF REEF SYSTEM STRUCTURE
Coral reefs are optimized for high productivity and self-sufficiency within the
nutrient-depleted surface layers of tropical oceans (Darwin, 1897; Hatcher, 1988;
Larkum, 1983; Lewis, 1977). Their biological functioning is broadly mediated by
physical processes that control transfers of organic material and inorganic nutrients.
Therefore, the degree of hydrodynamic closure at internal and external boundaries
fundamentally defines the ecosystem and establishes reservoirs for budgets of biotic
and abiotic materials. Inherently, internal compartment processes dominate over the
trans-boundary processes that control fluxes between reservoirs within the ecosystem
(Hatcher, 1997a; Hatcher, 1997b). An essential concept is that boundaries within coral
reef ecosystems separate compartments whose dominant processes differ and operate
on different characteristic scales. Consequently, commonly recognized reef geomorphic
zones, for example, lagoon, reef-flat, reef-crest, and forereef slope, normally represent a
biological zonation that is paralleled by the spatial pattern of dominant physical
processes. Geomorphologic break lines that can be recognized by moderate resolution
satellite mapping sensors trace process-defined boundaries, sites of strong gradients in
advection, water-mass mixing, and wave-energy dissipation (Done, 1983; Hatcher,
1997a).
3.2 METABOLISM AND CORAL REEF GEOMORPHOLOGY
Although investigation of entire reef systems, and in particular reef-slopes and
lagoons, is incomplete, the existing data set of carbon-flux measurements reveals that
reef structure is a major determinant of internal variation in E within coral reef
ecosystems. The shallow perimeters of reefs are usually net autotrophic, and while a
portion of the implied excess production is used for local growth, some is exported
from the reef system, and some is transported inward (Hatcher, 1990). Typically, the
outer-reef-flat exhibits the highest metabolic rates, and high excess production here and
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Coral Reef Ecosystem Process Studies & Remote Sensing
• segmented into biogeochemically distinct geomorphological structural zones
based on moderate spatial resolution multispectral satellite imaging
• establishment of time-space patterns of light and nutrients for the reef zones
(defined by the initial landscape segmentation) based on benthic landscape
irradiance and hydrodynamic models driven by low spatial - high temporal
resolution oceanographic and meteorological satellite sensors
• mapping of spatial distributions of intra-zone biotopes using high spatial
resolution airborne or satellite-borne sensors
• measurement of in situ process to determine benthic community metabolic
functions for the recognized biotopes
Guided by the regional distributions of environmental conditions modeled through
indirect remote sensing and the reef zone biotope maps obtained by mapping with high
resolution sensors, the spatially-distributed mixed community P g , R, E, and G for the
selected reef zone is calculated for a predetermined time increment. Iteration over time
increments and then over reef zones, followed by time and space integration, results in
seasonal or annual estimates of reef system E and G.
3.1 REMOTE SENSING OF REEF SYSTEM STRUCTURE
Coral reefs are optimized for high productivity and self-sufficiency within the
nutrient-depleted surface layers of tropical oceans (Darwin, 1897; Hatcher, 1988;
Larkum, 1983; Lewis, 1977). Their biological functioning is broadly mediated by
physical processes that control transfers of organic material and inorganic nutrients.
Therefore, the degree of hydrodynamic closure at internal and external boundaries
fundamentally defines the ecosystem and establishes reservoirs for budgets of biotic
and abiotic materials. Inherently, internal compartment processes dominate over the
trans-boundary processes that control fluxes between reservoirs within the ecosystem
(Hatcher, 1997a; Hatcher, 1997b). An essential concept is that boundaries within coral
reef ecosystems separate compartments whose dominant processes differ and operate
on different characteristic scales. Consequently, commonly recognized reef geomorphic
zones, for example, lagoon, reef-flat, reef-crest, and forereef slope, normally represent a
biological zonation that is paralleled by the spatial pattern of dominant physical
processes. Geomorphologic break lines that can be recognized by moderate resolution
satellite mapping sensors trace process-defined boundaries, sites of strong gradients in
advection, water-mass mixing, and wave-energy dissipation (Done, 1983; Hatcher,
1997a).
3.2 METABOLISM AND CORAL REEF GEOMORPHOLOGY
Although investigation of entire reef systems, and in particular reef-slopes and
lagoons, is incomplete, the existing data set of carbon-flux measurements reveals that
reef structure is a major determinant of internal variation in E within coral reef
ecosystems. The shallow perimeters of reefs are usually net autotrophic, and while a
portion of the implied excess production is used for local growth, some is exported
from the reef system, and some is transported inward (Hatcher, 1990). Typically, the
outer-reef-flat exhibits the highest metabolic rates, and high excess production here and
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Coral Reef Ecosystem Process Studies & Remote Sensing