Caspian Sea State of the Environment 2019
Sea in 2012–2014 as part of a special expanded programme at more than 100 stations were used. Data show that the concentration of organic pollu- tion in the north-western part of the Caspian Sea is negligible (Monakhov 2014a; 2014b; 2015). Analysis shows that the majority of the main in- dicators of sea bottom sediment contaminants
around oil and gas facilities in 2017 were within normal background concentration ranges. 5.5. Biodiversity The Caspian Sea’s biodiversity serves as an indi- cator of its overall environmental quality and the impacts of anthropogenic pressures. Russian sturgeon. Since the beginning of the 1990s, there has been a decrease in the number and biomass of commercial Russian sturgeon re- serves, although stocks are replenished annually through artificial reproduction. The Persian sturgeon mainly occupies the feeding area of the Middle and Southern Caspian, mak- ing spawning migrations from there. In the Volga River and its tributaries, there is not an extensive population. During the high-intensity fishing pe- riod, the size of the catch does not exceed 2 to 5 per cent of all sturgeon caught. Stellate sturgeon. In recent years, the surveyed water area of the Caspian Sea has experienced a steady decline in the stellate sturgeon population. Sterlet is the only species of sturgeon whose stock has not been declining as rapidly as beluga, stur- geon and stellate sturgeon. Many large groupings dispersed throughout the Volga (from the Volgo- grad Hydroelectric Plant dam to the desalinated waters of the Northern Caspian) and geographi- cally shorter spawning migrations, allowing max- imum use to be made of all existing spawning grounds, have helped to preserve sterlet reserves. Beloribitsa is listed in the Red Book of Astrakhan Oblast. Currently, the only way to preserve and restore beloribitsa stocks is through artificial re- production. The Caspian seal (Pusa caspica) is the only ma- rine mammal and endemic Caspian species listed as Endangered in the IUCN Red List of Threatened Species 2008. At the beginning of the twentieth century, the Caspian seal population numbered about one million. Despite hunting for Caspian seals having been prohibited by law in Azerbaijan since 1952,
Atyrau
2015
RUSSIA
2015
Astrakhan
2016
2015
2010-2015
2016
Co
2016
2010-2015
2016
2016
2016
KAZAKHSTAN
Aktau
Makhachkala
2014
2016
Derbent
CASPIAN SEA
Ni
Ni
AZERBAljAN
Sumgayit
TURKMENISTAN
Baku
Cd
Cu
Cd
2015
V Cu
Turkmenbashi
Co
2012
Ni
Ni
Ni
As
AN
Cr
Co
Al
2012-2016
V
Ni
Mn
Cd
Anzali wetland
2013
2015
2015
Cu
Ag
2016
Sr
2016
Rasht
Co
2012
2013
Gorgan
IRAN
2012-2013
Cr
Sari
As
Al
V
Cu
Co
Fe
Al
Al
V
Cr
Ni
V Co
Co
Ni
Sediment fraction
the fide tor
Degree of increase in the concentration of heavy metals by the NOAA-SQuiRTs indicators
Sampling areas in sediments
Undivided sand Large silt
Toxic results Non-toxic results Oil fields, samples of 2013
26 times higher
her
Fine silt Clay silt
2 3 5 8
Coquina Coquina with sand
Sampling year
2015
Ooids
Used ERL for marine and TEL for freshwater sediments
Salt Pre-Holocene deposits and outcrops of bedrock
0
100 km
Sources: Bastami et al., 2014, 2015 and 2017 ; Brekhovskikh et al., 2017; Buchman, 2008; Guliyev et al., 2014; Jamshidi et al., 2016 and 2017; Khalilova et al., 2016; Makhlun, 2017; Pakzad et al., 2016; Salahova et al., 2015; Sokurova, 2016; Tulemisova et al., 2016; Vosoogh et al., 2017; Zaferani et al., 2015; National Atlas of Russia, 2007; SoE-Kazakhstan, 2017; SoE-Seaport Aktau, 2017.
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