) ‫أنموذج ( أ ) الخاص برسائل الماجستير و اطاريح الدكتوراة ( اخر شهادة‬
University of Baghdad
College Name
College of science
Department
Department of Biology
Full Name as written in
Passport
Adil Mashaan Rabeea
e-mail
adelmashaan@yahoo.com
Career
Assistant Lecturer
Master
Thesis Title
Year
Abstract
Lecturer
Assistant Professor
Professor
PhD
The biodiversity of zooplankton and benthos invertebrates in Tigris and Euphrates
rivers, central Iraq
2006
The factors studied included water temperature ,electrical conductivity , salinity, total
dissolved and suspended solids, pH, total hardness , calcium, magnesium, chloride,
dissolved oxygen ,biological oxygen demand, dissolved orthophosphate ,nitrate, nitrite and
chlorophyll-a.The study also included relative abundance index(Ra) and used constancy
index (S ) to determine the constant Taxonomy units in both rivers environment .The study
included Shanon-Weiner diversity index (H),Simpson diversity index(D),Species richness
index (D*),Species uniformity index(E) and Sorensen similarity index(Cs) to determine
the values of invertebrates biodiversity in study area .
The results showed the discharge rates ,velocity and water depth were higher in Tigris than
in the Euphrates and water temperature was the same in both rivers which effected by the
surrounded air temperature .Electrical conductivity , salinity and total dissolved solids
were higher in the Euphrates. Total suspended solids recorded high values in the Tigris
due to effect of Tigris tributaries inside Iraq ,in addition of increase discharge rates and
velocity of water .
The study showed the pH values tended to slightly basic due to the calcium nature of study
area, as well as higher values recorded in late summer and autumn because of higher
phytpolankton population in those seasons .According to the total hardness values the
water in both rivers considered as a very hard and increased these values in the Euphrates
river. The increased discharge in the last two years leaded to decrease the total hardness
values in this study.
Among Ions the calcium was dominant ion and the magnesium were the second and
chloride, and recorded higher values of these ions in Euphrates.
This study showed that two rivers were well oxygenated with recorded little values of
BOD5 in Euphrates and these values less than 5 mg/L. Nitrate values which increased with
rainfall in winter and the concentrations of nitrate show increase in Tigris due to little
consumption by aquatic plants and phytoplankton in this river,while the orthophosphate
and nitrite were not regulated in seasonal and local variations.Chloropphyll-a was
increased in spring and autumn due to the suitability of water temperature and found of
nutrients which increased these values in Euphrates due to the high transparency .
The Zooplankton Showed High density in September in both rivers,while higher densities
of benthic invertebrates which recorded in April 2004 in Tigris and March 2005 in
Euphrates, with increased the densities of benthic invertebrates in the Euphrates.The
results of relative abundance index Showed Brachionus calyciflorus ,Polyarthera
dolichoptera belonged to rotifera and Bosmina longirostris ,Diaphanosoma braychurum
) ‫أنموذج ( أ ) الخاص برسائل الماجستير و اطاريح الدكتوراة ( اخر شهادة‬
belonged to cladocera and nauplii belonged to copepoda were the more abundant in the
Tigris ,while the Brachionus calyciflorus ,B.urceolaris, Lecane luna belonged to rotifera
and Bosmina longirostris and Daphnia leavis belonged to cladocera and nauplii belonged
to copepoda were the highest abundant in the Euphrates.The index showed the
Chronimidae and Tubificidae belonged to benthic invertebrates were more abundance in
both rivers.59 taxonomy unites belonged to zooplankton and 6 taxa units belonged to
benthic invertebrates were identified in the Tigris,while 64 taxa. units belonged to
zooplankton and 9 taxa belonged to benthic invertebrates were identified in the Euphrates.
Values the index of Species richness of zooplankton varied between 0.7-3.6 in the Tigris
and 0.50-4.8 in the Euphrates with higher values were recorded in April in Tigris and
September in Euphrates.While the index of species richness of benthic invertebrates varied
between 0.68-1.3 in the Tigris and 0.87-2.3 in the Euphrates with greatest values were
recorded in September in the Tigris and March2005 in the Euphrates.The results of
constancy index showed 10 taxa belonged to zooplankton and 4 taxa belonged to benthic
invertebrates which were considered constant in the Tigris river ,while 13 taxa belonged to
zooplankton and 4 belonged to benthic invertebrates which were considered constant in the
Euphrates river ,where the other taxonomy unites varied between accessory and accidental
Taxonomy units in study stations.
The Shanon-Weiner index of zooplankton varied between 0.9-1.8 bit/ind.in Tigris
and 0.7-2.4 bit/ind. In the Euphrates. Greatest values were recorded in March 2004 in
Tigris and Septumber in the Euphrates ,while the Shanon index of benthic
invertebrates varied between 0.63-1.28 bit/ind. In Tigris and 0.9-1.93 bit/ind. In the
Euphrates,with greatest values were recorded in October in Tigris and May in the
Euphrates.Simson diversity index of zooplankton showed values varied between 0.37
– 0.15 in Tigris and 0.55-0.11 in the Euphrates ,while simpson index of benthic
invertebrates varied between 0.55-.0.19 in the Tigris and 0.44-0.18 in the Euphrates.
These indices of zooplankton did not different between both rivers, while the indices
of benthic invertebrates recorded values were higer in the Euphrates than the
Tigris.The dcrease of diversity values in the Tigris due to different in hydrological
factors and little aquatic plants and increase turbidity in this river.
The uniformity index of zooplankton varied between 0.54-0.88 in the Tigris and 0.610.86 in the Euphrates but the uniformity index of benthic invertebrates varied
between 0.75-0.91 in the Tigris and 0.71-0.90 in the Euphrates. Higher values refer to
did not ecological stress on invertebrates in the study area .
The highest percentage of similarity of 82%. For zooplankton were reported between
stations 4 and 5 in Euphrates ,and highest similarity of benthic invertebrates
between stations 1 and 3 reaching 85.3%.
Satasical analysis showed positive correlation was found between biological indices
and chlorophyll- a, while negative correlation between most of these indices and
monthly discharge rates and T.S.S.
The results of ecological assessment of water in both rivers refer to supporting good
biodiversity and the environment in the two rivers considered health according to
the biological indices were studied ,and ecological integrity for the Euphrates was
higher than Tigris due to the higher indices which were recorded in the Euphrates .