Understanding the basic natural linkage among reef vitality, the coral fraction of the sand, and location opposite land masses or tidal passes is also essential to resource management. Variable coral-sand percentages correspond to similar variability in reef vitality and may be a tool for measuring coral health. Carbonate sands in a reef ecosystem are composed solely of skeletal grains of biota inherent to the ecosystem. In Florida, sands are formed in place and essentially remain in place. Intense wave action of storms and hurricanes redistribute but do not remove the sands from the confines of their origin.
Coral grains dominate sands where coral health is poor.
Halimeda and mollusc sands dominate where coral health is better. The healthiest reefs occur off land masses and the least healthy occur off the widest tidal passes. Throughout the reef tract, corals are generally perceived as declining. Coral-sand percentages mimic this decline by increased amounts in seaward and southwesterly directions. An increased understanding of the close linkage between, and variety in, the physical environments and biological communities is required.