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Слід відмітити перспективність даної території для репатріації в її межах популяції зниклого на Поділлі виду – Crocus angustifolius Weston., а також для створення нових популяцій інших рідкісних видів – Euonymus nana Bieb., Schiverekia podolica (Bess.) Andrz., Equisetum telmateia Ehrh. тощо. Природні екологічні фактори в межах урочища сприятливі для підтримання у ньому ще більшого біорізноманіття, ніж існує тепер.

У віддаленій перспективі урочище Кукулянське може стати ключовою територією при формуванні заповідної мережі національного рівня з метою охорони природного комплексу Мурафських товтр.

Література 1. Заповідні об’єкти Вінниччини / За ред. О.Г. Яворської. – В.: Велес, 2005. – С. 66.

2. Зелена книга України / За ред. Я.П. Дідуха. – К.: Альтерпрес, 2009. – 448 с.

3. Маринич О.М., Пархоменко Г.О., Петренко О.М., Шищенко П.Г. Удосконалена схема фізикогеографічного районування України // Укр. геогр. журн. – 2003. – №1. – С. 16–21.

4. Червона книга України. Рослинний світ / За ред. Я.П. Дідуха. – К.: Глобалконсалтинг, 2009. – 900 с.

5. Шиндер О.І. Види роду Pulsatilla (Ranunculaceae) на території Мурафських товтр // Вісн. ім. Т. Шевченка. Інтродукція та збереження рослинного різноманіття. – 2009. – Вип. 25 – 27. – С. 13–15.

6. Шиндер О.І. Поширення та стан популяцій Crocus reticulatus (Iridaceae) і Tulipa quercetorum (Liliaceae) на території Східного Поділля // Укр. бот. журн. – 2009. – 66, №4. – С. 489–497.

LInkaGE oF SoIL aLGaE to SpECIFIC haBItatES Vinnikova О.I.

Kharkiv national university named by V.N. Karasin, Kharkiv Soil algae are mandatory components of any biogeocenosis. Due to autotrophy, these microorganisms act as initial producers of organic matter, pioneering colonizers of various substrates and active participants of the soil- formation process. Algaesynusia arise on the surface and in the depth of the soil under the influence of surrounding environmental (i.e. physical and chemical) factors and higher plants. At the same time, algae by themselves can affect other soil microorganisms and higher plants, and these relationships vary from a hard competition for substrates to mutually beneficial co-existence.

When the phytoedaphon is compared between biogeocenoses, which are different in one particular parameter (e.g. higher plants, humidity, insolation rate or soil pH), it becomes possible to reveal the sets of species that are specifically associated with the particular habitat characteristic. This work aimed at identification of the sets of soil algae species in several biogeocenoses of the Eastern Ukrainian Forest-Steppe with different gradient of the habitat conditions.

Two groups of plots investigated. One group comprised monoculture plantations of Pinus sylvestris L., Betula pendula L. and Populus tremula L. grown during 20-45 years on the left bank terrace of Severskiy Donetz river (Zmijiv district, Kharkiv region). The soil was an unstructured semi-sand on alluvial sands, with humus weight contents about 0.3-3.4 % in the upper soil layer (0-5 cm) and pH 4.9-7.00 in the litter and 4.4-6.0 in the soil.

The plots were chosen to be typical for the studied area and to represent different tree strains and humidity levels;

Каразинские естественнонаучные студии Каразінські природознавчі студії Karazin natural science studios the latter were classified as dry, fresh or humid.

The second group consisted of eight cretaceous chalk outcrops located on the bank of Vovcha river (Vovchansk district, Kharkiv region). Four plots had a grass projective covering of about 10-30 %; one plot was under the brushwood of Prunus spinosa L.; two plots were the plantations of Pyrus communis L.; and one plot was covered with the lichen Colemma tenax (Swark) Ach. em. with a projective covering about 90%.

Before sampling recently fallen leaves were removed and material was collected aseptically from semidecomposed litter and soil layers 0-5 cm and 15-20 cm in forest plantations, and from litter and soil layers 0-and 10-15 cm in chalk outcrops. Litter and soil samples were processed using methods of cultures on growing slides, soil-water cultures and agglomeration cultures on agarised medium BBN [1]. Algae were cultured at 20-°C under illumination (16 h per day at 2000 lk). Identification of algae species in these cultures was carried out periodically during 1 month, using “hanging drop” or “crushed drop” preparations. Life cycles and reproduction stages of algae species were studied using “hanging drop” and fixed (paraffin sealed) preparations, and also in vivo in 24-48 h cultures established from the primary cultures [1].

In total, in the litter and soil of forest plantations 80 algae species were identified and 42 species were found on the cretaceous chalk outcrops. The systematic structure of the phytoedaphon in the forest plantations mainly contained Chlorophyta, Bacillariophyta and Xanthophyta; the proportion of green algae exceeded 50 % of the total number of species found. On the chalk outcrops Cyanophyta dominated, but if leaf trees were present, the proportion of cianobacteria became reduced due to a sharp rise of the Chlorophyta part.

Within the forest plantation group the number of Chlorophyta species was higher in pine plantations compared to leaf tree plots. Concurrently, litter and soil in birch and aspen plantations contains more Bacillariophyta species than in cultivated pine forests. An intersting feature was a pronounced increase in the number of Cyanophyta and Bacillariophyta species on highly humid plots, whereas Xanthophyta showed a clear preference of dry or fresh habitats.

On the chalk outcrops the number of Cyanophyta species was markedly higher compared to forest cenoses, but Chlorophyta were not that much diverse. It was found that the proportions of Chlorophyta, Bacillariophyta and Xanthophyta within general algae species contents on the chalk plots covered with leaf trees appeared to be rather similar to that in the phytoedaphon structure of the forest plantations.

Sometimes in the literature concerning phytoedaphon relations to the higher plant covering, the pine forests were described as poor in algae, and species diversity were found to be higher in leaf forests [1, 3]. It was explained by relatively low concentration of organic compounds in the soil under pines, whereas a plentiful spectrum of nutrients is developed under leaf trees, especially oaks [2]. However, the availability of nutrients can be considered as an important factor for heterotrophic microorganisms (i.e. fungi), and in case of algae it might be relevant to the small group of mixotrophic species. Our data shows that on the plots with the same soil type and in absence of undergrowth, the tree type per se does not play a key role for the quantitative diversity of algosynusia.

In our study the list of species found in pine plantations included 58 species, and in leaf plantations 56 algae species were present. Within the total list of species found in this group of plots, 34 species (42.5 %) occurred in both pine and leaf plantations. Instead, algae diversity appeared much more dependent on the humidity level.

Among 80 species 74% were present in the soil of highly humid habitats. Probably, this positive correlation is caused by specific role that water plays in algae growth and reproduction by regulating organic nutrient and mineral concentration and availability, pH, oxygenation level, biological activity of various metabolites and agents, which are produced by algae and other members of microbial community in the soil [2, 6].

It was shown that increases or decreases in the insolation level could cause significant changes in soil algae development, as there are light-addicted and darkness-resistant forms. Algae can protect themselves against excessive insolation with external dark-pigmented mucous covers, additional pigments and intracellular inclusions of oils with high carotin contents [5].

According to the common opinion, Cyanophyta are considered as the most resistant to the excessive sunlight. The presence of macroscopic films of cyanobacteria on the soil surface in the open habitats were reported by many authors [5]. Our data confirm the earlier judgments concerning the ability of Cyanophyta to anchor themselves on the substrate depleted in nutrients, like chalk outcrops, and to grow actively in conditions of low humidity and high insolation. It can be supposed, that the development of Cyanophyta in forest plantation soils was limited by shading, but also by antagonistic influence of the metabolites produced by other microorganisms (fungi and other algae) and chemical agents present in root and litter excreta.

In forest plantations fallen leaves forms a litter, and particularly in this layer the algae species diversity reached the maximum. In this group of plots 72 % Chlorophyta species and 77 % Bacillariophyta species were present in the litter. At the same time, the highest numbers of species of Xanthophyta and Cyanophyta in the forest plantations were detected in the soil layer 0-5 cm.

Каразинские естественнонаучные студии Каразінські природознавчі студії Karazin natural science studios Among eight studied chalk outcrops the litter was present on three plots, and here a significant increase in species diversity was observed in the litter of the brushwood of Prunus spinosa L. (60 % species found at this plot), whereas no such effect existed on the plots under Pyrus communis. The possible mechanism may involve a negative influence of the root excreta from the pear-tree, which are high in organic acids and phenols [4].

The differences in qualitative spectrum of algae between biogeocenoses with different types of soil and different density of higher plant covering are obvious. However, any conclusions about the specific association of certain species with certain habitat conditions must be drawn very carefully.

In our study there was a number of typical species, which occurred on 50 % plots within each of two groups of biogeocenoses. Among them we found three species, which turned up as typical for both forest plantations and chalk outcrops: Bracteacoccus minor (Chodat) Petrov, Myrmecia biatorellae (Tschermak-Woess et Plessl) B. Petersen, Pinnularia borealis Ehrenberg. Also species Stichococcus bacillaris Ngeli, Hantzchia amphioxys (Ehrenberg) Grunov in Cleve et Grunov and Coccomyxa cf. solorinae Chodat were quite frequent in the forest plantations and sometimes observed on the chalk plots. Two species – Navicula cryptocephala Ktzing and Trichromus variabilis (Ktzing ex Bor-net et Flahault) Komrek et Anagnostidis – were frequently detected in the soil of chalk outcrops and also were recorded with middle to low regularity in the forest plantations. In total, among 107 soil algae species found in the studied area, 15 species (14 %) appeared to be common for both groups of biogeocenoses.

References Водорості ґрунтів України (історія та методи дослідження, система, конспект флори) / Костіков І.Ю., Романенко П.О., Демченко Е.М., Дарієнко Т.М., Михайлюк Т.І., Рибчинський О.В., Солоненко А.М. – К.:

Фітосоціоцентр, 2001. – 300 с.

Журавлев Ю.Н. Влияние водорастворимых веществ хвойного соснового опада на развитие почвенных водорослей в лесных биогеоценозах // Ботанический журнал. – 1989. – Т. 74, №12. – С. 1769-1774.

Кузяхметов Г.Г. Водоросли зональных почв степи и лесостепи // Почвоведение. – 1991. – №9. – С.

63-72.

Мороз П., Осипова І. Фенольні сполуки як чинник алелопатичної активності груші // Вісник Львів.

ун-ту. Серія біологічна. – 2004. – Вип. 36. – С. 249-253.

Приходькова Л.П. Синезеленые водоросли почв степной зоны Украины. – К.: Наук. думка, 1992. – 218 с.

Rosa K., Lhotsk O. Edaphische Algen und Protozoen im Isergebirge, Tschechoslowakei // Oikos. – 1971.

– 22. – P. 21-29.

SprInG phytopLankton oF ZayanDEhrUD rESErVoIr (ESFahan proVInCE, Iran) Zarei-Darki B.

Department of Biology, Islamic Azad University, Falavarjan Branch, Esfahan, Iran, e-mail: zarei@mail.ru Zayandehrud reservoir located on height about 1950 m above sea level in the Zagros Mountains in the Esfahan - Sirjan Basin (50 ° 15’-50 ° 45 ‘ N; 32 ° 30 ‘-33 ° 00 ‘ E). Zayandehrud Reservoir is the most important water object of the Central Iran as a source of pure water for Ostans (an administrative province) of Esfahan, Yazd, Chahar mahal va Bakhtiyari and Kerman.

The drainage area makes more than 2500 км2 (Moenian, 2008). Average depth is 40 m and the maximal depth come up to 100 m; water-surface area is 48 км2 and reservoir volume makes 1090 million in m3 but these parameters are constantly fluctuating. Fluctuations of a level are concerned with: a) temporary seasonal waterflows (waters from melted snow); b) rainfall falling; c) water evaporation during the dry period. Temporary and permanent inflows flow into the reservoir but Zayandehrud River sprang from the Zardkuh Bakhtiyari Mountains at the height of 4221 m above sea level is main among them. In the territory of country including Central Iran, the basic water mass (up to 80 %) runs on the rivers during the spring period and summer mean water is very low.

Study of reservoir algal flora in the spring season was aim of the present work when the maximal water volume is observed. Phytoplankton materials for the present study were collected by the author from 4 transects (everyone transect contained 3 sampling stations). Expeditionary departure has been made in the April of and 31 algological samples of phytoplankton have been sampled on the surface, at a depth of five and ten meters.

Qualitative samples were taken by a planktonic net which was dragged lengthways transect during 2-5 minutes;

Каразинские естественнонаучные студии Каразінські природознавчі студії Karazin natural science studios quantitative samples were carried out by Ruttner bathometer and then they were counted in the Gorjaev chamber.

Parameters like temperature, salinity, the EC, DО, pH were taken during sampling. In middle of transects, samples were taken for measurement of parameters as Nt, PO4, HCO3, Na, SO4, Mg, Ca, P, NH4, NO3. Methods of sampling, processing, and storage of the algological material are those generally accepted in algology (Determinative tables of fresh-water algae in the USSR, 1951-1983; Determinative tables of fresh-water algae in the Ukrainian SSR, 1953-1991; Swasserflora …, 1978-1999; Vodorosli …, 1989).

As a result of the processing of phytoplankton data in the period under review, 27 species, belonging divisions were revealed.

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