Preferencje help
Widoczny [Schowaj] Abstrakt
Liczba wyników

Znaleziono wyników: 3

Liczba wyników na stronie
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 1 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników

Wyniki wyszukiwania

Wyszukiwano:
w słowach kluczowych:  ekologia gatunku
help Sortuj według:

help Ogranicz wyniki do:
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 1 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników
Crocothemis erythraea (Brullć, 1832) has been recorded in Poland at 11 localities in Southern and eastern parts of coun­try, and one in western part - this work presents the new locality from this region, with description of observations and the analysis of literaturę data. C. erythraea is a typical thermophilous, Mediterranean species, which reproduces in Africa, southwestern Asia and in most Southern and central European countries, to circa 53°N. On the distribution border short-lived populations are sometimes found. C. erythraea was observed in the year 2002 in a pond near village Gostyń Stary, 51°54’N, 16°57’E, by Gostyń, 65 km to the S of Poznań. It was the same water body where Aeshna affinis was recorded in 1995. It was a middle-size pond, with the area of ca. 25x120 m and its long axis directed to W-E. In the middle the shallow place with Phragmites australis was found. The who- le water column of water body was densely overgrown by Chara sp., up to the surface. Chara sp. divided the water surface on smaller areas (see photo). Inshore - sparsely T. latifolia. The shore of the whole pond linę grown by Alnus glutinosa individually. In those days, maximum air temperatu­rę at noon was 34°C. On 10 July 2002, sińce 2 pm, two terri- torial males, which sat on the last year's stalks of P. australis, were observed. The distance between them was ca. 5 m. From time to time (2-10 min.), one of two ma­les had flown round the water surface, next, the second one followed its footsteps. Unexpectedly, about 5.30 pm, both males flew away to the east, despite that the inso- lation was still very good and air tempera­turę went down “only” to 31°C. Next day, 11 July 2002, both males ap- peared on their own positions at 11 am. Ana- logous situation from day before was obse- rved, moreover, one of the males rinsed ab- domen during the flight. The specimens were moderately skittish - their escape distance was 3 m. Co-existing species in those days were as follows: Calopteryx splendens, Lestes spon- sa, Platycnemis pennipes, Erythromma viri- dulum, Ischnura elegans, Coenagrion pud­la, Anax imperator, Cordulia aenea, Soma- tochlora metallica, Libellula ąuadrimacula- ta, Sympetrum flaveolum, S. sanguineum. Interaction between C. erythraea and the mentioned above species was not observed. Although the females were not observed, reproduction was very possible (abdomen rinsing could show on earlier copulation). Unfortunately, larvae and exuviae searches from 18 V, 8 VI, 21 VI and 2 VII 2003 did not give positive result. Presented data are the first from Poland, which gives information about adults C. ery­thraea behaviours. In comparison to litera­turę data from Germany, where this species was recorded regularly and often, the de- scribed information are typical for this dragonfly. Specimen activity, fly time and behaviour are very similar. In our climate, C. erythraea is not fastidious species at se- lection of environment. It could be any sta- gnant water body with dense aąuatic vege- tation. It must be sufficiently deep and can not freeze to the bottom in winter. The de- scribed pond possessed a few additional features: it was sunny, covered from wind well and shallowed by overgrown Chara sp. Chara sp. limited water circulation and waving which facilitated heating of super- ficial layers of water. Literaturę descriptions show other plants performing the same function: Ceratophyllum, Myriophyllum (typical substrate of oviposition) and Utri- cularia. C. erythraea prefers clean and elear water. It is possible, that pieces of Chara sp. had one morę function in this water body. The bottom of this pond was heterogene- ous, partly of clay, and water usually was stirred by fish and waterfowls. Within the areas of Chara sp. water was always clean. The most essential feature of this pond was his specific microclimate, which make an impression Mediterranean or subtropi- cal climate: strong insolation, stagnant air and high temperaturę and humidity. There are similar reąuirements for A. affinis, which often co-exists with C. erythraea, which shows similar microclimate preferen- ces. Others characteristics species, which may co-exist with C. erythraea, are: Leucor- rhinia caudalis and Orthetrum cancellatum. They have most similar habitat preferences. Sympetrum fonscolombii and E. viridulum can be also found. The second one, is a ther- mophilous species, which prefers Myrio- phyllum or Ceratophyllum vegetation type. C. erythraea is a thermophilous species, given as an example and proof of global warming. Every year, from European co- untries, lying on the same geographical la- titude like Poland (for example from Gre- at Britain, Holland, Germany, Ukraine), where species was only regarded as a rare migrating element, numerous data about new localities has been given in recent years.
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 1 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.