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trap silt that could smother reefs , and cleanse nearshore water by the
uptake of nutrients and pollutants . Also , they provide local people
with food and medecine, as well as wood for heating ,cooking and
house building.
Unfortunately, many governments and developers consider mangrove
swamps to be virtual wastelands with little economic value for Human
beings except when cut back for their timber , for the development of
shrimps aquaculture , or for the establishment of resorts.
(source : invitation to oceanography .2006.p : 436,445)
Exercises :
Exercise : read the following questions and choose the right
answer :
1-salt marshes grasses possess the same characteristics as terrestrial
plants :
a-true.
b-false.
2-salt marshes grow : a- in muds and sands.
b-in the bottom of the ocean.
3-salt marshes are continually covered by seawater :
a- True.
b- B-false.
4-salt marshes are : a- productive natural environments.
b-non-productive natural environments.
5-sediments, plant detritus , dissolved nutrients are flushed into and out
of the marsh : a- True.
b-False.
6-salt marshes are subdivided into : a-two principle zones.
b-three principal zones.