Salinity Species like fish and prawns migrate and thus avoid stressful salinities when conditions are unfavourable The less mobile organisms such as Cyclograpsus punctatus can’t tolerate salinities below 20% migrating into certain suitable sections of the estuary. Sesarma catenata moves further into the estuaries as it tolerates 7% but S. eulimene occur near the head of the estuaries where salinities reaches 2. 7% Floods influences the salinity levels and result in very low salinity which kills estuarine bivalves however the Dosinia hepatica survives by clamping its shell tightly shut, resulting in excluding the water when salinities drop below 14%. When experiencing low salinity some organisms regulate the concentrations of salts in its tissue …show more content…
Therefore broad, flat blades in plants such as Ulva, Porphyra and Aeodes have large surface area, allowing the photosynthetic pigment to be near the surface of the plant to aid in the maximum absorption of light for photosynthesis. This let these plants grow faster than cylindrical forms such as Bifurcaria and Splachnidium.

3.3 Complete the following table: (15) Forest Nama Karoo
Location Ranges from the Soutpansberg in the north and Maputaland in east to Cape peninsula in the west small patches of forest
The Knysna and Tsitsikamma mountains along southern and eastern coastal region Central plateau of western half of S.A extending into the south eastern Namibia,
Climate High rainfall of- in summer >525mm-
With winter rainfall- >725mm
Strong summer rainfall Arid with unpredictable extended droughts. Rainfall occur late summer with as MAP ranging from 70mm- in north- west 500mm in the south-east; Temperatures of - 5°C in winter with 43°C in summer; Frost in winter.
Characteristic plants Woody vegetation from 3m shrubs to 30m high forests
Species richness is very