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2.3.3. WATER ECOSYSTEMS At present the fresh ecosystems of the coastal zone (river and lake) are changed intensively under the anthropogenic influence and practically transformed into the agrocenoses and systems of inhabitant areas with active economics. Marine ecosystems represented by pelagic and benthic unions. 2.3.3.1. Pelagiale The members of pelagic aggregation are vegetative (bacterio- and phytoplankton) and living (zooplankton, pelagic fishes, Caspian seal) organisms. Bacterioplankton of water mass makes an active mineralization of organic matter of the allochthonous and autochthonous origin. Biomass of microorganisms varies horizontally and vertically depending upon the season (water temperature) and also upon the quantitative and qualitative composition of organic matter presenting in water. The organic matter is formed mainly by the river flows, sewage of towns and cities and industrial objects, oil contamination, outbursts of the underwater mud volcanoes, etc. By-seasonal definition of the bacteria totality reflects the increase of their number in spring-summer period and decrease in autumn-winter period as well. In addition the seasonal changes are observed only in water layer up to 200-m depth. Generally the reduction of bacteria totality with depth is observed. 150-20-m deeper this index reduces in 2-7 times in comparison with the surficial layer depending upon the season. According to data of 1988 in the shelf zone of the Middle Caspian (up to 100 m depth) the total number of bacteria is: 528 ths./ml in winter, 1115 ths./ml in spring, 2085 ths./ml in summer, 1150 ths./ml in autumn. At the same time the maximal number of bacteria is observed within 25-m depth. The quantity of saprophytic bacteria in 1 ml. of water reaches: 3 in winter, 221 in spring, 333 in summer, 209 in autumn. In winter the saprophytes are spread even enough in water mass. Their number in surficial and benthonic layers varies a little. At the same time the sharp increase of saprophytes quantity in the surficial layers, shallows especially is observed when little increase of temperature in spring. In addition the saprophytic bacteria react sensitively to quality and origin of the organic matter: in regions being far from the industrial waste the shallows are characterized by maximal content of microorganisms. The average value of the bacterial production in the shelf zone varies from 24 to 263 mg/m3 per day, and the bacteria biomass varies within 8-10 mg/m3 per day. Time of bacteria generation varies in wide ranges - from 10 to 63 hours. In winter the reduplication of bacteria number passes in 2.5 times slower than in summer, in the benthonic layers their reproduction passes more slower than in the surficial ones. The changes of the bacteria production and biomass take place mainly from the surface up to 200-m depth, lower they stay unchanged. In the shelf zone of the South Caspian the total number of bacteria in seasons is in 1.5-2 times more than the same one in the Middle Caspian and practically doesn't fall 1 m./ml below. Besides it, there is an absence of sharp border in bacteria number in seasons, and zone of the bacteria maximum number is wider and takes nearly the whole line of 50-m depth. The dynamics of saprophytes development in the long-standing seasonal aspects is identical to that of the bacteria total number, and the changes of their average number is connected with the those factors which are typical for the bacteria general number. The quantity of saprophytes in 1 ml. of water varies in great ranges (depending upon the season, depth and place of determination): 11 to 600 in winter, 9 to 1740 in spring, 11 to 2120 in summer and 11 to 1371 in autumn. Generally, the sharp increase of the saprophytes during last 20-25 years is observed in the South Caspian. Moreover, the area with high number of saprophytes widens towards the open sea. In Baku Bay the bacteria total number (according to 1978) was 3600 ths./ml, and the quantity of saprophytes in 1 ml. exceeded 1900. It is connected with intensive enrichment of ate with the allochthonous organic matter. Waters of bay influence upon the surrounding areas in the south-eastern and the south-western directions for 15-20 miles. The studies of 1976-1977 had distinguished 316 cultures of bacteria on Apsheron shore of the South Caspian. They are corresponded to the genus of Mycobacyerium, Mycococcus, Pseudomonas, Micrococcus, Sarcina, Planosarcina, Pseudobacterium, Bacterium, Chromobacterium, Vibrio and Bacillus. The bacterial cultures are represented by 76 species and 31 varieties, 34 species of them are cocci, 20 are spore bacillus, 17 are sporeless bacillus, 5 are microbacterial forms. The average value of the bacterial production in the shelf zone of the South Caspian varies during a year from 34 to 105 mg/m3 per day, and biomas - from 32 to 188 mg/m3. Time of the bacteria generation is for 10 hours more on average than the same one in the Middle Caspian in all the seasons. Phytoplankton is distinguished by scantiness of marine species and the predominance of the salt-water ones. Among 171 species of phytoplankton typical for Azerbaijan sector of the sea the leading role is belonged to the diatomic algae (Bacillariophyta), which are spread on the whole water area and their species composition is more various (75 species of 22 genus). Among them the genus of Chaetocerus is distinguished according to species variety, 16 species varieties and forms, 3 of them are endemics of the Caspian Sea. The second one is the genus of Thalassiosira, consisting of 11 species, varieties and forms, 5 of them are endemics. On the third place there are the genus of Coscinodiscus - 8 species, varieties and forms. Further on there are the genus of Melosira and Nitzschia - 6 species, varieties and forms. From the genus of Coscinodiscus the species of C.jonesianus and C.granii are more widely spread near Azerbaijan shore. Marine genus of Rhizosolenia artificially inhabited into the Caspian with 3 species must be pointed out especially. In the Caspian Sea it plays a great role (in particular, the genus of Rhizosolenia calcar-avis), it is a dominant making 75-90% of the whole biomass of phytoplankton and develop significantly on the whole water area, sometimes making a "flowering" of water. The genus such as Actonocyclis, Sceletonema, Thalassionema are represented by small number of species, varieties and forms. But they are widely spread. Some of them develop all the year round and play a great role n sea life. In the coastal zone of the sea and the islands of Baku archipelago the benthoplankton and benthonic species of genus of Grammatophora, Achnates, Campylodiscus, etc. developing in plankton in great volumes play a special role. The second one according to meaning are blue-green algae (Cyanopyta) represented by 55 species and forms of 13 genus. The family of Oscillatoriceae is represented in plankton with more sorts. Here the genus of Oscillatoria is distinguished according to species variety. Unlike blue-green algae the peridiniales are the native inhabitants of the Caspian and represented by 23 species, varieties and forms of 9 genus. In addition according to biomass abundance they take the second place after the diatomic ones. Prorocentrum cordata is corresponded to wider distributed species. It is one of the dominants vegetating in mass from spring to autumn. During a mass development of Rhizosolenia calcar-avis the role of Prorocentrum cordata decreases. Prorocentrum scutellum, Pr.micans, Glenodinium, caspicum, etc. observed on Azerbaijan shore by separate spots are corresponded to the accompanying species. The group of green algae (Chlorophyta) is represented by a little number - 15 species, varieties and forms of 8 genus which have an insignificant development. On the freshened areas there are Pediastrum simplex, P.boryanum, Scenedesmus quadricanda, etc. Ulotrix algae - Binuclearia lauterbonii have more wider distribution in plankton. Golden (Chrysophyta) and euglenic (Euglenophyta) algae near Azerbaijan shore are represented (each group) by 2 significant species and have an insignificant distribution. The phytoplankton distribution (on number and biomass) on the seasons is unequal and reaches its peak in summer-autumn months. As results of studies of 1975-1976 the phytoplankton biomass in the Middle Caspian varied from 0.013 g/m3 in winter to 0.422 g/m3 in summer and 0.741 g/m3 in autumn. In the South Caspian the biomass increased from 0.155 g/m3 in winter up to 0.929 g/m3 in summer. The data correlation on long-standing changes of the phytoplankton biomass in the period of lower (1974-1975) and high (1991-1999) sea level had revealed the scariness of algae number and biomass. It is associated with increased contamination of the Caspian, especially with oil products, it leads to intoxication of living organisms and death of algae steadfast to contamination. On the background of the general reduction of number and biomass of phytoplantkon Rhizosolenia calcar-avis and Prorocentrum cordata keep their leading position dominating in sea about 50 years. Zooplankton. The main fund of zooplankton providing the fish population of Azerbaijan sector of reservoir is constant practically, and consists of 40 species and subspecies. Their representatives are observed regularly in planktonic samples. The main part of zooplankton are the species of the caspian origin. Three complexes of organisms are distinguished in distribution of various species of zooplankton in the Middle and South Caspian. They inhabit:
The typical species of zooplankton of the coastal zone are - Calanipeda aguae dilcus, Acartia clausi, Heterocope caspia, Podonevadne camptonux, P.angusta. The presence of numerous larvas of the benthonic organisms it typical for spring and summer plankton of the coastal zone. In spring over 50% of total biomass of the plankton is formed by larvas of Balamus and larvas of Mollusca in summer in the Middle and the South Caspian as well. The dominating species of the central chalistic zone are Eurytemora grimmi, E.minor, Limnocalanus grimaldii and mysides - Mysis caspia, M.macrolepsis, Paramysis baeri. The inhabitants of this zone make a daily vertical migrations. The daily vertical migration of zooplankton is depended mainly upon the season ands light day duration. The light factor is the determining one in zooplankton distribution. The intermediate zone has a mix composition of population. Here the species of the shallow and the central, chalistic zone are observed. According to biomass there is a domination of Eurytemora grimmi and E.minor. On the western shore of the Middle and the South Caspian there is a domination of Cladicera according to species number in zooplankton - 55-65% of the species total number. By the quantitative development the predominating group is Copepoda forming 75-90% of the zooplankton total mass. Among Copepoda the dominating species are Eurytemora grimmi, E.minor, Acartia clausi, Calanipeda aguae dilcus, Limnocalanus grimaldii which are observed in all; seasons. Among Cladicera the following species Podon polyhemoides, Podonevadne trigona, P.camptonyx macronyx, P.camptonyx podonoides, Evadne anonyx producta, E.anonyx deflexa, etc. can be frequently observed. The anthrpogenic contamination of the sea influence harmfully on hydrofauna, including zooplankton. In this connection on the western shore of the Middle and the South Caspian zooplankton is distributed unevenly. In the very contaminated region from Sumgayit up to Shakh Dili the plankton biomass is lower than in the clean zones of Samur and Lenkaran. According to materials of observations (1975) in the region of Pirallakhi is. the zooplankton biomass was only 137.7 mg/m3, in clean waters of Derbent it was 137.7 mg/m3. In the South Caspian in the contaminated region near Shakh Dili the zooplankton biomass was 63.4 mg/m3, in clean zone of Lenkaran - 195.5 mg/m3. Analysis of long-standing data on the zooplankton study for period of 1974-1999 generally reflects a tendency of increase of biomass and zooplankton specific variety as well in the Middle and the south Caspian. The specific composition of zooplankton had been added by species of Acartia clausi, new for the Caspian, it had been discovered in summer 1982 on the western shore. Further on it had inhabited widely on the whole South Caspian and became a dominant in some seasons. The increase of zooplankton species composition in 90s had been caused by species from suborder Harpacticoida and Cyclopoida not determined earlier, and the fresh water forms as well. The plankton biomass in the Middle Caspian had increased from 2.2 g/m3 in 70s up to 3.1 g/m3 at present, in the South Caspian from 2.8 g/m3 up to 6.0 g/m3 accordingly. Probably, the increase of total biomass of zooplankton and its specific variety together with favourable hydrological-meteorological conditions is also associated with noticeable reduction of the anthopogenic contamination and significant increase of the Caspian Sea level. Ichthyofauna. All species of herrings, sprats, silverside, mullets, shemaia, pipefish, white sturgeon, asp and pelecus are corresponded to the pelagic fishes. Sprat, mullet, silverside, pelecus, shemaia, pipefish, some herrings feed with zooplankton (which in its turn consumes up t 37% of total biomass of phytoplankton), partially with phytoplankton and the benthonic organisms, sometimes with fish youths. The rest pelagic fishes, and the caspian seal as well, are the predators feeding mainly with sprat, herring, silverside, goby, other small fishes and fish youths. The majority of fishes inhabit in the coastal zone up to 50-75-m depth, but the herrings can migrate to 10-13-m depth, and some sprats (anchovy and big-eyed shad) - up to 200 m. The specific composition of the pelagic fishes is nearly equal with the benthonic ones, but the pelagic fishes predominate according to biomass (sprats especially). 2.3.3.2. Benthal Benthal ecosystem consists of benthonic bacteria, phyto- and zoobentose, and the benthonic fishes as well. Hereinafter the water vegetation and organisms overgrowing on mobile and stable objects of the anthropogenic origin, i.e. periphyton are corresponded to the benthonic formations. Microflora. The totality of bacteria in benthonic ground of the Middle Caspian shore varies in wide ranges - from 0.2 to 8.7 mlrd./g of wet ground. Moreover, in winter period their number is minimal. In all seasons the number of bacteria (except Samur section) increases from the shore to open sea (50-10-m depth). At the same time there is no interrelation between the ground type and bacteria number in it. The minimal quantity of bacteria in ground of the shallows from Sungait up to Pirallakhi is. (from 210 to 600 m./g during a year) is associated with the negative influence of the industrial waste. The maximal index of Samur section (3.7-8.7 mlrd./g) is explained by the river flow influence. The number of saprophytic bacteria varies upon the seasons, depths and areas similar to changes of the bacteria total number and varies within 54-2840 ths./g during a year. The total number of bacteria in grounds of the South Caspian shore varies on seasons within 2.6-5.6 mlrd./g on average. The number of bacteria in winter is 2 times and 1.7 times less than in summer. The great variations of the bacteria number on seasons are observed in the coastal zone with exception of 10-m depth of Shikh section and Kura river mouth. In the region of Shikh section the influence of organic matter of the allochthonous origin is expressed in the opposite action to that is observed in zone of Kura river mouth - 1.7-2.1 mlrd./g (the minimal index of the coastal zone of the South Caspian) accordingly as compared with 9.6-13.3 mlrd./g (maximal index). Number and distribution of the saprophytic bacteria, their seasonal changes are similar to dynamics of the microorganisms' total number change. In addition the total number of saprophytes of the present zone is maximal for the Caspian Sea and varies within 0.32-10 m./g during a year. Microphytobentose is represented mainly by blue-green (60 species, represented by 67 forms) and diatomic (155 species, varieties and forms) algae, consisting of numerous and various species of different ecology. Bluish-green algae are corresponded to two classes (Chroococcophyceae and Hormogoniophyceae), the leading place takes Hormogoniophyceae, the family of Oscillatoriaceae has the most variety. Diatomic algae are corresponded mainly to a class of Pennatophyceae with exception of some species from order of Discodales of class of Centrophyceae. The genus of Oscillatoria Vauch., Lyngbya Ag. (Cyanophyta) and Nitzschia Hass., Navicula Bory (Bacillariophyta) differ with special richness of species taking a leading place in sea microphytobenthose near Azerbaijan shore. But though these genus are represented by great number of species most of them don't reach a significant development. More rich and diverse Cyanophyta are represented in zone of splash and on small depths and rocky substrate and hydrotechnical constrictions where they develop richly, especially in summer-autumn period. The presence of oils and oil products reflects negatively on the microphytobenthose. The system studies of the production number and biomass of microphytobenthose has not been carried out up to now. Macrophytobenthose. The genus of Enteromorpha, Polusifonia and Cladophora are richer according to species number among the known algae-macrophytes (51 species, 1 subspecies and 1 form) in Azerbaijan sector of the sea. Sea flora is corresponded to marine-salt-water one with the predominance of red algae over the brown ones, it shows warm-water regime of the Caspian Sea. The phytozenose of green algae Enteromorpha linza and E.clathrata is spread on the seashore near Nabran settlement, in zone of splash. Further on, in Prigilyazi region the stones and ridges in zone of splash are covered with green algae Enteromorpha linza, and near the water-land border ater and lower there is Cladophora vagabunda with mix of red algae Ceramium elegans and Laurencia caspica. On the depth of 1.5-2.5 m on stones there are associations of red algae Ceramium elegans and Laurencia caspica, in the lower stage there is another red algae Lophosiphonia obscura, partially the algae can be covered with Ceramium elegans + Enteromorpha prodifera and Enteromorpha clathrata, on the depth of 6-7 m - Dermatolithon caspicum; on the depth of 8.8 m - Laurencia caspica + Ceramium elegans + Dermatolithon caspicum, on the depth of 8-12 m one can observe Acrochaetium thuretii if the substrate is rocky. In region between Gilyazi Dili cape and Shakh Dili cape (island and banks of Apsheron archipelago also included) there are favourable conditions for settlement and development of algae. It is revealed not only in enrichment of specific composition, but in widening of line of algae settlement up to 15-m depth and in increase of dominating form up to 10 and more. More luxuriant development of algae is observed on depth 0-8 m. All these is explained by increase of water limpid, strong cut of coastal line, existence of numerous banks, ridges, source of desalinization unsignificant in comparison with the previous regions. Pringsheimiella scutata, Enteromorpha flexuosa sub.sp.biflagelata, laurenciocolax polyspora had been discovered only in this region. Saprobic forms such as Enteromorpha compressa are developed mainly in insignificant quantities on bottoms contaminated with living-municipal waste. Sea sector from Baku Bay to Kyur Dili cape is characterized by abundant enough development of algae due to numerous outcrops of rocks grounds and high enough thermoregime and water limpidity. In addition there is a nearly absence of desalinization sources. Here the abundant development of algae on depth 0-14 m is observed. More better they develop on depths 0-3.5 m. Enteromorpha prolifera, E.flexuosa, E.clathrata, E.linza, Claetomorpha aerea, Cladophora serices, Cladophora vagabunda, Acrochaetium thuretii, Dermatolithon caspicum, Ceramium elegans, Plysiphonia caspica, P.elongata, Lophosiphonia obscura, Laurencia caspica grow in a great quantity. The genus of Callithamnion kirillianum is met only in this region. From Kyur Dili cape up to Astara the coastal line is relatively straight (except Gizilagach gulf) with presence of sandy grounds or with ooze mixture. All these make unfavourable conditions for development of algae-macrophytes on this sea zone. So, the growths of algae-macrophytes are confined mainly to the shallow gulf closed from all-directed winds by Kyur Dili cape, mainly these growths are formed by chara algae Lamprothamnus alopecuroides which is the only mass form of this region. Brown algae are absent in this region. High water vegetation near Azerbaijan shore is represented by some species: Zostera noltii - sea grass, Potamogeton pectinatus - combed rdest and Ruppia maritina - marine ruppia. From them only sea grass plays a significant role in sea life forming in some places of the western shore the considerable growths. These growths form underwater landscapes being the shelter for numerous invertebrates and fish. In particular, between Pirallakhi is. and Kyur Dili is. on sandy, sandy-shell and sandy-oozy grounds there are sea grass growths on 1.5-5-m depth. More thicker growths are observed on the area from Sangachal cape up to Bandovan cape. Here zostera covers a bottom by wide spots taking significant areas. Here the flowering plants of combed rdest and marine ruppia are observed in some places. A considerable quantity of sea grass is observed in Gizilagach gulf, rdest and ruppia are also observed here but in more quantity. Microzoobenthose of Azerbaijan sector of the Caspian Sea consists mainly of infusoria (Ciliophora), foraminifers (Foraminiferida) and ostracoda (Ostracoda), the role of other groups (Nematoda, Turbellaria, Heliozoa, Nemertini) is insignificant. The representatives of 15 orders of infusoria (Karyorelictida, Prostomatida, Haptorida, Pleurostomatida, Trichostomatida, Colpodida, Synnymenida, Nassulida, Cyrtophorida, Hymenostomatida, Scuticociliatida, Peritrichida, Heterotrichida, Oligotrichida, Hypotrichida) - altogether 439 species had bee found in the Caspian Sea. From them 305 species had been pointed out in microbenthose, 172 species in periphythone and 135 species - in plankton as well. According to the species number and quantitative type of infusoria the richest part of the sea is the western part of the Middle (199 species) and the South (223 species) Caspian. 129 species of them are common for both water areas. The minimum development of infusoria is found in the coastal medium- and fine-grained sands where 289 species had been found on number 5-6 m./m2. In other types of sands the average quantity of infusoria exceeds 2 m./m2, but oozy grounds are more scanty - 2-5 ths./m2. Vertical distribution of infusoria according to sand types is also different. Their maximal number (6-8 m./m2) is typical for 0-4-cm layer. With the depth increase there is a scantiness of species and infusoria number. The coarser the sand then the more depth of infusoria penetration as well as depth on which high indices of microorganisms number are observed. Among the periphythonic infusoria the most number had been established on the western shore of the South (125 species) and the Middle (106 species) Caspian. Moreover, 90 species are common for both water areas. Three maximums in development of infusoria microbenthose falling to spring, summer and autumn lots had been pointed out, with maximal development in summer. Generally, on depth 0-15 m the quantity of species and infusoria number is higher than on 25-100-m depths. It is explained with oozed sand, deterioration of bottom enlightenment degree and water temperature decrease. In winter with temperature decrease the density of infusoria in all ground layers reduces, and the day and night maximums of the number became less distinct. Generally, infusoria fauna has a cosmopolitan character, and in spite of low water salinization, consists only of marine species. Foraminifers inhabit mainly in the sea benthose and divided into two groups. 12 species widely spread in Azerbaijan sector of the sea are corresponded to the first group. They are as follows: Ammobaculites neobeccarii caspica, A.verae, Cornispira minuscula, Elphidiella broizkajae, Florilus trochospiralis, Miliammina fusca, Retroelphidium shochinau, R.caspicum, Spiroplectinata perexilis, Birsteiniolla macrostoma, Ovammina leptoderma, Hemisphaerammina sp. Species spread only in the South Caspian and the southern part of the Middle Caspian are corresponded to the second group: A.exiquus contractus, Ladammina polystoma caspica, S.risillus, Trichohyalis aguayoi, H.tenuicutis. The areal of foraminifers of the first group covers the coastal shallows and bears sharp variations of temperature and saltiness. More halo- and thermophilic species are corresponded to the second group. Among them the numerous are Trichohyalis aguayoi which is spread on depth up to 15 m. The maximal depth of foraminifers distribution is 60 m. Generally, among foraminifers the mass subspecies is Ammobaculites neobeccarii with number up to 9000 specimens per 10 cm3 of ground. Among the ostracodes on the western part of the Middle Caspian there had been revealed 21 species, and 4 species on the South Caspian. The dominating one is Cytherissa informis Faradew, then Cyprides littoralis, Leptocythere crispata, Cytheromorpha fuscata, Eucypris inflata, Hemicythere sicula, Cyprides eittoralis, etc. According to biomass ostracodes form 2 maximum in the Middle (10 m and 50 m) and the South (50 m and 100 m) Caspian as well. For the majority of ostracodes the inhabitant zone spread up to 105-m depth. In regard to grounds the ostracodes biomass forms 2 maximums: the first one - on soft grounds (0.048 g/m2), the second one - on shelly grounds (0.04 g/m2). On the oozy-shelly ground the ostracodes biomass is minimal - 0.015 g/m2. Macrozoobenthose of the Caspian Sea is represented by 16 groups and 306 species of the benhtonic animals, from them (according to studies materials of 1989-1991) 96 species inhabit in Azerbaijan sector of the Middle Caspian and 55 species - of the South Caspian as well. They are, mainly the mollusks (Mollusca), making 70-75% of macrozoobenthose biomass, and also the cankerous (Crustacea), worms, hydroids (Hydrozoa), Briozoa, sponge (Spongia), chironomides (Chironomidae). The main mass of mollusks are Abra ovata, Dreissena rostriformis, Mytilastes lineatus, Cerastoderma lamarcki. From the cancerous there is a prevalence of balanus (Balanus improvisus), amphipodes (Amphipoda). Nereis diversicolor and Hypania invalida are widely spread among the worms. The species composition of the macrozoobenthose of Azerbaijan sector of the sea is given in Appendix. In Azerbaijan part of the Middle Caspian according to species number the first place is taken by cankerous - 60%, mollusks are on the second place - 28%, 12% falls to the lot of the rest species. The main biomass of the benthonic animals is concentrated on depth up to 50 m, reaching its maximum in interval of 25-50 m. It is explained by favourable ground regime (ooze with shells). The seasonal changes of biomass are characterized by minimal values in winter, the gradual growth in spring-summer period and reduction of biomass from August to October. In all seasons mytilastes, abra, dreissena and nereis predominate according to biomass. According to data of 1976 the average mass of the benthose in the western part of the Middle Caspian was 155.8 g/m2. In Azerbaijan sector of the South Caspian the cankerous - 66% and mollusks - 21% predominate according to species number. The biomass distribution on depths and seasons differs little from such on the Middle Caspian. But the main biomass is concentrated on depths up to 25 m. In addition in all seasons mollusks dominate there - dreissena and abra among them. Balanus and crab predominate among the cankerous, worms take the third position according to biomass. According to data of 1989-1991 the benthose mass varied within 35.5-68-98 g/m2. The average biomass of benthose in 1991 was 47.56 g/m2 with number of 1438 specimens/m2. Ichthyofauna. Sturgeon, stellate sturgeon (sevruga), sterlet, barbel sturgeon., salmons, roach (Caspian roach, Black sea roach, Scardinius erytrophthalmus), bream, carp, pike perch, (golden) european carp, all kind of gobies and Benthophilus are corresponded to the benthonic fishes. Sprats, small herrings, gobies, Benthophilus, fish youths are feed for ravenous fishes (stellate sturgeon, salmons, pike perch). Sturgeon and barbel sturgeon are the benthonic organisms and fishes. The rest species are the main consumers of the benthose, partially eating plankton. The main part of fish inhabits in the coastal zone, but gobies can come up to 600 m down. 2.4. Trophic aspects According to feeding the living organisms of the coastal zone are divided into the primary producers of organic matter, its consumers and reducers. The producers of the caspian ecosystem are mainly algae (phytoplankton and phytobenthose). Herbivorous invertebrates, the majority of fish youth and some adult fishes, testudines, birds are corresponded to the consumers of the first order; the consumers of the second and the next orders are such zoophagous as ravenous invertebrates; catfish, pike-pearch, pike, sturgeons, etc. from fishes; water snake from amphibians; cormorants from birds; caspian seal from the mammals. The producers of the near-water ecosystems are algae and higher plants. The later are subdivided into two classes of formations - amphibian and water. The consumers are a complex animal kingdom beginning from zooplankton, herbivorous invertebrates and vertebrates and completing with ravenous and parasitic species. The main reducers of water and near-water ecosystems are detritus bacteria and fungus. The producers of the land ecosystems are the higher plants, producing the primary organic production from non-organic matters. Concumers-phytophagous from the invertebrates and animals exist by the primary production making the secondary production at the same time. The consumers-zoophagous of various orders feed with the secondary production. All the macroconsumers partially return the nutritive into the environment as waste of living processes. But the main reducers are the corresponding bacteria and fungus. Fishes are represented by marine and fresh-water species having the following fodder supply:
The main acclimatized species have the following fodder supply:
Amphibians feed mainly with various invertebrates including the pests. Very seldom there are various kinds of grassy vegetation in their fodder supply. The fodder supply of amphibians living in the coastal zone consists of:
Reptiles of the coastal zone distinguish with great variety of species and feed with vegetative and animal food, exactly:
Birds of the coastal zone are characterized by great quantity of the subspecies variety mainly by migrating and wintering species and subspecies. The local birds make fewer a third of species and subspecies observed in region. Fodder supply of birds is very extensive and includes various vegetative and animal food, and also the waste and remnants of food products. Fodder supply of birds of the coastal zone consists of:
According to feed character the mammals of the coastal zone are divided into omnivorous, herbivorous and carnivorous. The theriofauna is represented by 7 orders, which are characterized by the following fodder supply:
Ungulates are represented by three families - pig (wild boar), deer (roe deer) and hollow-horned (gazel), their fodder base is:
Acclimatized species have the following fodder supply:
Reference
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