The Black Sea Coastal Waters Pollution In The Period Of 1990-2000 On Monitoring Materials
The Black Sea coastal waters pollution in the period of 1990-2000 on monitoring materials
of Ukrainian marine hydrometeorological UNITS
Y.P. Ilyin, N.P. Klimenko, A.I. Ryabinin, S.A. Shibayeva
Marine Branch of Ukrainian Hydrometeorological Institute (MB UHMI),
Sevastopol, Ukraine
Marine units of the Ukrainian hydrometeorological network, together with MB UHMI, fulfil monitoring of the marine water pollution in their regions in framework of long-term program. This program assumes hydrometeorological observations and water sampling on marine monitoring stations of I, II and III categories, using small ships and boats belonging to these units. Information about observational regions and stations is presented in Table 1. Stations of I category require every 10-day observations on first priority pollutants and dissolved oxygen (DO). Stations of II category should be sampled every month and stations of III category every season of the year in order to obtain full set of hydrological and chemical data, including pollutant chemicals. This means observations on water temperature, salinity, pH, transparency and colour, contents of DO, hydrogen sulfide (HS) and forms of nitrogen (N), phosphorus (P) and silicon (S). Complex of pollutants includes oils, detergents (D), some chemical forms of carbolic acid (CA), chlorine hydrocarbons (CH), polychlorinebyphenyls (PCB), heavy metals and toxic elements group (mercury, chrome, iron, cadmium, etc.). Results of monitoring are synthesized in MB UHMI and arranged in the form of “Marine water quality yearbook” on measured chemical indices, including calculated index of pollution for comparable periods. Brief description of some characteristic conclusions from monitoring data on chemical regime and pollution of the Black Sea (Ukrainian part) coastal waters is given below, using these Yearbooks materials for the time interval 1992-2000. Comprehensive data and analyses on the Black Sea pollution for previous decades, till 1995, are published earlier [1].
Oils. Practically, oils polluted all of studied waters. Highest levels of pollution were at the Danube seashore, in Odessa harbour, Sevastopol
Bay and the Dnieper-Bug estuary. Mean annual concentrations in these regions were 0.06-0.62 mg/l. As an example, interannual variability of water pollution of the Dnieper-Bug liman is illustrated by Fig. 1. Some another character of variability is demonstrated for the Sevastopol Bay and adjacent open seashore (Fig.2).
Chlorine hydrocarbons. High concentrations of some CH (e.g., gamma-hexachlorinecyclohexan and heptachlorine) were observed in the Sevastopol Bay and open seashore near Sevastopol (up to 8 ng/l), in the mouths of South Bug and Danube rivers (up to 270 ng/l) and near the Southern Seashore of Crimea (up to 58 nm/l).
Polychlorinebyphenyls. Mean annual concentrations of PCB for some studied areas did not exceed 20 ng/l. Pollution levels for other regions (Sevastopol Bay, Danube delta and Dnieper-Bug liman) were 2-3 times more and had reach 400 ng/l.
Carbonic acid (phenols). Among all studied areas, Southern Seashore of Crimea had the least polluted water by CA (less than 3 mkg/l of mean values). Most polluted was Odessa harbour’s water (33 mkg/l). Chlorinephenols and nitrogenphenols in significant amounts were observed in Sevastopol Bay and open seashore waters. Sometimes their contents had reach more than 1000 ng/l. Content of o-, n- and m-cresols was changed within the Sevastopol Bay waters from 10 to 320 ng/l.
Detergents. Analysis of mean annual concentrations has revealed two regions most polluted by this toxicant – Odessa harbour and Sevastopol’s bay and seashore. Maximal concentrations of detergents were observed in the first half of described period in these areas (up to 900 and 600 mkg/l, respectively). Besides, detergent pollution of water in Odessa harbour has a stable character during the entire period of observations. Waters in other regions of monitoring are not polluted by this toxicant.
Some forms of nitrogen and phosphorus. Maximal concentrations were traditionally connected to mouth areas of Dnieper, Danube and South Bug rivers, reaching 1100 mkg/l of total P (mouth of S. Bug River) and 5800 mkg/l of ammonium N (delta of Danube River).
Mercury. Now waters of the single region of this pollutant monitoring (Sevastopol’s Bay and open seashore), in general, are not polluted by labile form of mercury. However, in 1994-1996 extremal concentrations were registered, reaching 140-930 mkg/l.
Hydrogen sulfide. During the whole period, the presence of HS was registered in summer time in the Dnieper-Bug estuary bottom water. Highest contents were observed in the Bug liman (9.4 ml/l) and the Dnieper liman (8.28 ml/l) and explained by anoxia events.
Dissolved oxygen. Surface waters of all regions were well aerated, DO content varied from 96 to 128 % of saturation. Characteristic variations of DO in surface water are demonstrated on the example of Sukhoy liman (Fig. 3). DO deficit is typical for the bottom water of the Dnieper-Bug estuary in warm season of the year. In other regions deficit was observed episodically. In general, DO contents in bottom water varied from 0 to 125 % of saturation.
Complex index of water pollution (IWP). In Yearbooks of marine water quality, the degree of pollution is estimated by a complex index computed from several important chemical concentrations (normalized by their ultimate available concentrations) with subsequent classification of water quality on IWP. Table 2 contains IWP values for all of monitored regions together with class numbers and their description. During the period studied, most polluted were waters of Odessa harbour, Sevastopol Bay and the Dnieper-Bug estuary. Positive tendency is revealed for a water quality improvement of the Sukhoy liman and the Yalta Bay. Within other regions of monitoring, such improvement is not observed.
For a better understanding of marine coastal water pollution state and tendencies, joint analysis with the open (deep-water) Black Sea areas monitoring data would be useful, while further co-ordination of intra- and inter-agential environmental monitoring programming and implementation is necessary as well.
Table 1. Monitoring regions and stations
Monitoring region
Station categories
Station numbers
Lat. min-max, N;
Long. min-max, E
Sukhoy liman and inlet channel
I
II
2
8
46°15’00” – 46°20’06”
30°38’02” – 30°40’18”
Odessa harbour
I
2
46°29’02” – 46°31’00”
30°36’00” – 30°45’30”
Sevastopol Bay and open coastal waters
II
III
5
13
44°35’15” – 44°37’24”
33°30’48” – 33°34’48”
Southern seashore of Crimea
I
II
III
3
3
25
44°22’36” – 44°40’54”
33°59’48” – 34°26’48”
Delta of the Danube River
III
14
45°19’00” – 45°20’00”
28°40’00” – 29°30’00”
Dnieper-Bug liman
I
II
III
3
7
14
46°09’08” – 47°01’15”
31°25’04” – 32°18’17”
Table 2. Complex water quality characteristics in compare periods of 1990-1999: Water pollution index (WPI) and water quality class number (WQC). II - clear; III – moderately clear; IV – moderately polluted; V – polluted; VI – very polluted; VII – extremely polluted.
Region of monitoring
Years
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
Delta of the Danube River
WPI
3.07
3.32
1.88
0.93
0.97
1.03
1.22
2.09
1.46
1.23
WQC
IV
IV
III
II
II
III
III
III
III
III
Dnieper-Bug estuary
WPI
1.85
3.09
3.54
3.32
2.48
2.54
2.38
2.19
3.37
2.01
WQC
V
VI
VI
VI
V
V
V
V
VI
V
Sukhoy liman
WPI
2.24
1.85
1.66
1.84
1.39
1.50
1.50
1.43
1.47
0.78
WQC
V
V
IV
V
IV
IV
IV
IV
IV
III
Odessa harbour
WPI
5.49
6.82
4.91
3.71
1.99
3.32
2.70
4.20
2.80
2.66
WQC
VII
VII
VI
VI
V
VI
V
VI
V
V
Sevastopol Bay
WPI
1.58
1.54
2.35
2.02
2.24
2.01
2.76
1.66
1.83
2.74
WQC
IV
IV
V
V
V
V
V
IV
V
V
Yalta Bay
WPI
1.36
1.50
1.27
1.83
0.80
1.28
0.92
1.05
0.62
0.66
WQC
IV
IV
IV
V
III
IV
III
III
II
II
Fig.1. Oils in the Dnieper-Bug estuary water
Fig.2 Oils in the Sevastopol’s Bay
and open seashore water
Fig. 3. Dissolved oxygen contents in the Sukhoy liman water
Reference
1. Hydrometeorology and hydrochemistry of the seas. Vol IV: The Black Sea. Issue 3. – Sevastopol, “EKOSI-Hydrophysika”, 1996, 230 pp.
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