الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
Summary
Pollution in the southern part of Lake Manzala led to high levels
of contamination and high organic load affecting consequently all aquatic
organisms including fishes. Therefore, a five-year GEF project was
implemented last decade by UNDP and Ministry of water Resources
Irrigation to tackle the problem of polluted drainage water that enters the
Lake from Bahr El-Baqar drain, using Engineered wetland for biological
treatment. Physico-chemical parameters have been analyzed in water
samples collected seasonally during the period from winter 2012 to
autumn 2013 along to lake, drain; before and after Engineered Wetland
station,
The obtained results could be summarized as following:
1) Water temperature recorded values were within the range between
31.6 ± 0.1°C to 15.1 ± 0.1°C at Bahr El-Baqar drain before
Engineered Wetland Station (1) during summer and at Lake Manzala
Station (6) during winter respectively. Temperature value didn’t
exceed the permissible limits of Law 48/1982, Ministerial Decision
92/ 2013.
2) Electrical conductivity values ranged between 5.39 ± 0.05
mmhos/cm to 2.81 ± 0.01 mmhos/cm at Bahr El-Baqar drain station
4 during atumun and Lake Manzala station 3 during summer.
3) The total dissolved solids values ranged between 1901.00±2.90 mg l-
1 at Lake station 3 during winter to 3502.00±2.90 mg l-1 at drain
station 4 during spring. The concentration of total dissolved solids in
the present study was higher than that of permissible limits of Law
48/1982, Ministerial Decision 92/ 2013 (2000 mg l-1) at the drain
and some stations of Lake Manzala.
4) The pH values ranged between 8.20 ± 0.10 to 7.68 ±0.06 at the
drain at stations 1 during spring and winter respactivly. The pH
value of water samples collected from Lake Manzala and Bahr El-
Baqar drain were within the permissible limits of Law 48/1982
Ministerial decision 92/ 2013, (6.5- 8.5)
5) Transparency of water ranged between 20.67 ± 0.58 cm to 75.33±
0.58 cm at Bahr El-Baqar drain station 4 during winter and Lake
Manzala during autumn station 6.
6) Dissolved oxygen recorded values were within the range of 1.67±
0.06 to 5.7±0.1 mg l-1 at station 1of the drain and station 3 of the
lake during winter and spring respectively, the permissible limits of
Law 48/1982, Ministerial decision 92/ 2013, is not less than 4 mg/l,
The concentration of DO of water samples collected from the drain
exceeded the limits, but at the lake were within the permissible
limits.
7) Ammonia ranged between 4.14±0.32 to 0.61±0.3 mg l-1 at Bahr El-
Baqar drain station 1during winter and Lake Manzala station 6
during autumn.
8) Nitrate recorded values were within the range 4.14±0.06 to
0.61±0.01mg l-1 at Bahr El-Baqar drain station (1) during winter to
Lake Manzala station (3) during autumn.
9) Nitrite concentrations ranged between 0.83±0.02 and 0.21±0.02 mg
l-1 at Bahr El-Baqar drain stations 1 and 4 during summer to Lake
Manzala station 3 during winter.
10) Orthophosphate concentrations values were in the range of
1.39±0.01-0.41±0.01mg l-1 at Bahr El-Baqar drain station 4 during
spring to Lake Manzala stations 3 and 6 during winter.
11) Total phosphorus values were within range of 2.07±0.06-0.71±0.01
mg l-1 at Baher El-Baqur drain station 1 during spring to Lake of
Manzala stations 3 and 6 during winter.
12) Biological Oxygen Demand (BOD) values were within the range of
47.67±0.50 to 20.00±1.00mg l-1 at Bahr El-Baqar drain station 4 to
Lake Manzala station 6 during winter. The permissible limits of Law
48/1982, Ministerial decision 92/ 2013, is 80mg/l BOD values were
not within the permissible limits to the samples collected from
different site of lake and within the permissible limits at the drain.
13) Chemical Oxygen Demand (COD) values were in the range from
71.00±1.00 to 25.30±0.58mg l-1 at Bahr El-Baqar drain station 4
during summer to Lake Manzala station 3 during spring. The
permissible limits of Law 48/1982, Ministerial decision 92/ 2013, is
60mg/l. Chemical Oxygen Demand within the permissible limits to
the samples collected from different site of lake and within the
permissible limits at the drain.
14) Sulfate concentration values were in the range of 373.00±2.50 to
565.00±5.00 mg l-1, at Lake Manzala station 6 during spring and at
Bahr El-Baqar drain station 4 during summer.
15) Chloride ion ranged between 1275.00±3.50 and 401.00±2.89 mg l-1
at Bahr El-Baqar drain station 1during winter and Lake Manzala
station 6 during summer respectively.
16) Sodium concentration ranged from 301.00±2.80 to 653.00±2.80 mg
l-1 at Lake Manzala station 6 during winter to Bahr El-Baqar drain
station 1 during spring .
17) Potassium concentration ranged from 19.67±1.20 to 38.70±0.60 mg
l-1 at Lake Manzala station 3 during spring to Bahr El-Baqar drain
station 4 during winter
18) Calcium concentration ranged from 174.67±0.58 to 241.00±1.00 mg
l-1 at Bahr El-Baqar drain station 2 during winter and station 4
during summer respectively.
19) Magnesium concentration ranged between 56.67±2.8 and
91.00±3.60 mg l-1 at Bahr El-Baqar drain station 2 during winter and
station 4 during summer respectively.
20) Fecal coliforms counts ranged between 19×103 and 69×103
cfu/100ml at Bahr El-Baqar drain station 2 during spring and station
4 during winter respectively. The permissible limits of Law 48/1982,
Ministerial decision 92/ 2013, is 5000 CFU/100ml. The count in
Lake Manzala and Baher El Baqur drain exceeded the permissible
limits.
21) Total coliforms counts ranged between 110×103 and
630×103cfu/100ml at Manzala station 6 during summer to Bahr El-
Baqar drain station 1during winter respectively.
22) The distribution and accumulation of some heavy metals (Al, As, Cr,
Co, Ni and Se) were studied in the water and the Nile Tilapia O.
niloticus, Results showed that the concentrations of heavy metals in
water followed the order Al>Ni>Cr. Heavy metals As, Co and Se
were not less than the detection limits in all water samples at the six
selected sites. Al and Ni levels in water were higher than the
international permissible limits of Australia and New Zealand. The
levels of the heavy metals in gills and muscles of the Nile Tilapia
followed the order Al>Ni>Co>As>Se and Cr. The concentrations of
heavy metals Al>Ni>Co>As>Se and Cr exceeded the maximum
permissible limits in all fish muscles. According to Law 48/1982,
Ministerial decision 92/ 2013, As and Se levels are within the
permissible limits but Ni and Cr exceeded the limits at the study area
in the water samples.
23) The community of the benthic invertebrates was represented by 23
species included in three groups; Arthropoda, Annelid and Mollusca.
24) Arthropoda was the main bulk of the standing crop of the benthic
invertebrates constituting 51.1% & 48.19% at the arain and the
respectively. It was represented by 5 taxa, at the drain and the lake,
namely; Palaemon elegans, Echinogammarus veneris, Corophium
orientale Schellenberg, Mysis larvae and Chironomus larvae. The
most dominant taxa at the drain and the lake were Corophium
orientale Schellenberg during all seasons. It constituted 53.4% and
69.6% of the total Arthropoda at the drain and the lake, respectively.
25) Annelida was represented only by Limnodrilus hoffmeisteri
Claparede and Allolobophora sp. at each of the drain and the lake
during the different seasons.
26) Mollusca was represented by 16 taxa included in two classes,
Gastropoda (14 taxa) and Bivalvia (2 taxa).
27) Gastropoda was represented by Melanoides tuberculata Muller,
Theodux (Nerita) niloticus Reeve, Cleopatra bulimoides Olivier,
Bellamya unicolor Olivier, Valvata nilotica, Planorbis planorbis,
Lymnaea natalensis, Bulinus natalensis, Gyranulus ehrenbergi,
Biomphalaria alexandrina, Bulinus truncatus, Physa acuta,
Hydrobia musaensis and Lanistes carinatus. Gastropoda constituted
82.2% and 88.3% of the total Mollusca at the drain and the lake. The
most dominant species was Melanoides tuberculata Muller
constituting 19.7% and 39.5% of total Gastropoda.
28) Bivalvia was represented only by two taxa namely; Cardium edule
and Corbicula consobrina. It constituted 17.8% and 11.7% of the
total Mollusca at the drain and the lake, respectively.
29) Macrobenthic fauna is considered a good indicator for the biological
and environmental status of the aquatic ecosystem to examine the
associations between the population density and the stations,
maximum biodiversity at drain stations 1 and 2 and minimum in lake
station 6.
30) Biodiversity of bottom fauna in the bottom of the lake was affected by
two main factors; the first is direct supply of water from the southern
drains, and the second is the intrusion of the sea water from the
Mediterranean Sea.
31) Water Quality Index (WQI) showed that overall water quality
status of Lake Manzala and Effluent of Engineered wetland station
are fair and that of the drain is poor during all seasons, according to
WQI.
CONCLUSION
Bahr El-Baqar drain considers as one of the most sources of
wastewater along Lake Manzala. Increased of nutrients, organic matter,
domestic, agricultural and industrial effluent destructed many of habitats
in Lake Manzala.
Engineered Wetland station improves water quality of Bahr El-
Baqar and reduced some pollution-chemical and biological parameters.
The count of bacteria in Lake Manzala and Bahr El-Baqar drain
exceeded the permissible limits.
The concentrations of heavy metals in water followed the order
Al>Ni>Cr. Heavy metals As, Co and Se were not detected in all water
samples at the six selected sites. Al and Ni levels in water were higher
than the international permissible limits of Australia and New Zealand.
The levels of the heavy metals in gills and muscles of the Nile Tilapia
followed the order Al>Ni>Co>As>Se and Cr. The concentrations of
heavy metals exceeded the maximum permissible limits in all fish
muscles.
Macrobenthic fauna is considered a good indicator for the biological
and environmental status of the aquatic ecosystem.