biological diversity and tropical forests in tunisia - PART

Ic the maquis, Hyrtus cornnucis acd rosemary Rosmaricus officicalis
bracches are harvested for the distillatioc of oils acd fragracces. Large
q~actities of the placts are cut, wbich alters the species conposjtioc aid
decreases vegetatioc cover.
Species conpositioc was also altered by reforestatioc work dore by the
Forestry Directorate. Large areas have been planted to pice, eucalyptus
and acacia. Eiicalyptus plactations have ac especially sigrificact
5.r-fluerce oc species compositioc sicce allelopa thi c conpoucds produced by
the trees restrict the growth of other species acd oftec virtually
elimicate the lower vegetation strata.
Small agricnltural plots are developed alocg part of the coast -
cotably at Cap Serratacd Sjdj Nechree. There are also several villages
alocg the coast.
3.1.2. C~lf of Tu~is: Eizerte to El Haouaria (cap br)
The coast fron Rizerte to Raf Raf (Portn ~arica! is a tracsj tjoc from
the rocky shores srd st€€? sloyicg bgttons of thc Coral Coast to the
sh6llaver waters acd higher percectace of sacdy beaches ic the Cclf of
Tmis. Fron P6f Raf t~ Solinar the coastlire 5s fairly 1 ~ acd u flat with
macy coastel plalcs ecd ac estiery at the mccth of Oied Xedjerda. At
Kocrbo,~ acd agajc at El Yao;aria the shores are steep acd rocky dlie to
the extecsj~c of the Yicjsiac 9orsal mouctaic rarge thracgh Cap Eoc.
Icsjde a lice fran Bizerte to F1 Hao,aria the area of the sea deeper
tha~ :OC n is relatively small. Sallrity ic the Gjilf of Tiicjs averages 37
ppt ard water tenperatires average 17' C (Flee-0thmac 1973). Shallow water
acd the shelter~cg effects of the bay forned by the Cap Boc pecicsula,
greatly affect the physical a ~ d bSolo~ical conpocerts of the coast.
Year ace~al ternp~ratiires fron Bizerte to T~cjs are slightly higher
6
thar :8 C. Fron Ti;cj.s to El Hao~aria the moiictairs of Cap 3oc resclt ic
0
a slight drop ic average ternperat.ires, biit they are still ceer :8 C. The
average acciial precipitatior rate drops from 600 m at Bizerte to 500
at Ref Raf, thee to dCO - 500 nun fror. Tucis to Korboiis. Betweec Korbous
ard El Yaoiiaris the acr~al precipitatjo~ is iccreased by the n~crtajc
icfliiecce to 500 - 700 mm.
Ocly ore oct of five days is calm in Tucis. Domicact wicds are from
the w-nil, but east wicds are also very common and lacd-sea breezes are
reg,lar. The bioclimate is Subhemid, hot wicter variart. Ocly 15 kn
iclacd the bioclimate chacges to Seni-arid Superjor.
kch of the iiplacd from Bizerte to Raf Ref is c>iltjvated. There is a
large plactatjoc (c.3,000 ha) of njxed tree species bordericg over 10 km
of coest1ir.e bctw~er. 3zerte acd Cap Zebjb. At Cap %bib the no,rtaks
meet sea, resiiltice ic areas of rocky, eroded snrdstoce coastljce
icterspersed an9r.g the sardy beaches. Tide1 p ~ols with a variety of fama
acd flora are comnor. ic the rocky hreas.