A BOTANICAL IMPORTANCE RATING OF SELECTED CAPE ESTUARIES

A formula has been developed which allows a single numerical botanical importance score to be calculated for estuaries. The formula includes the area cover of each estuarine plant community type, its associatio n with the estuary, its condition and the plant community richness. Th is study focused temporarily and permanently open estuaries along the Cape coast, which for convenience was divided into four regions: Weste rn Cape; South-Western Cape; Southern Cape and South-Eastern Cape. Thi rty three temporarily and permanently open estuaries were studied and rated according to important within the whole Cape coast, regional imp ortance (i.e. Southern Cape or South-Eastern Cape) as well as against other estuaries of their type (i.e. temporarily or permanently open). The Olifants Estuary on the west coast received the highest importance score for the whole Cape coast. It has extensive marshes in its lower reaches that are in good condition. Reed and submerged macrophyte bed s are also a feature of this estuary. Two False Bay estuaries, the Lou rens and the Sir Lowry's Pass, and the lowest scores. These estuaries are severely impacted as a result of residential and industrial proxim ity, and rehabilitatory steps would be necessary to restore any botani cal significance to them. Not all the regions' estuaries were used to obtain these scores and more need to be included to make the importanc e rating relevant to all estuaries along the whole South African coast . This rating can be used to identify estuaries which are worthy of re ceiving a high conservation status.