Próba odtworzenia rozwoju roślinności w późnym glacjale i holocenie w okolicach Niechorza w Pomorzu Zachodnim

Abstract

 Na podstawie badań palinologicznych i datowań metodą ¹⁴C osadów organogenicznych odsłoniętych w klifie okolic Niechorza wyróżniono po raz pierwszy w Polsce północno-zachodniej najstarszy dryas. Sedymentacja opracowanych osadów trwała nieprzerwanie do okresu subborealnego.

AN ATTEMPT TO RECONSTRUCT LATE GLACIAL AND HOLOCENE HISTORY OF VEGETATIONAL COVER FROM THE NIECHORZE AREA IN WESTERN POMERANIA

The paper deals with organogenic deposits infilling two fossil melting basins nowadays exposed in marine cliff in the Niechorze area in western Pomerania (Figs. 1, 2). Palynological, geological and diatomological studies and ¹⁴C datings showed that the organic sedimentation continued from the earliest Dryas (12920 ± 330 y. BP) till the Subboreal times (Figs. 3–5, Tables 1–4).

Spectra from the earliest Dryas are characterized by a high contribution of sporomorphs transported over large distances and impurities whereas pollens of plants growing on the spot are innumerous. The BØlling time was characterized by a marked differentiation in composition of herbaceous plants in the spectra. Another transitional impoverishment of plant assemblages is found in the older Dryas. Forests, at first birch and later birch-pine forests, entered this area in the AllerØd. Their significance somewhat decreased at the advantage of herbaceous plants of open area assemblages in the younger Dryas. The Preboreal period was characterized by appearance of continuous birch-pine forests with some admixture of hazel and alder. The significance of pine forest rapidly increased in the Boreal times, at the end of which there also occurred line, oak and hazel. The peak in development of the forest cover took place in the Atlantic period (6310 ± 170 y. BP) when pollens of herbaceous plants completely disappeared from the spectra and stenothermal components of mixed forests and especially line became more important. The Subboreal period was characterized by decrease in contribution of forests at the advantage of herbaceous vegetation including synanthropic vegetation, presumably connected with the activity of Man.

The studies on organogenic deposits from Niechorze revealed a steady, gradual improvement of climatic conditions, recorded in the history of vegetational cover. The most interesting and, at the same time, most disputable data are those concerning the lowermost part of the profile (the oldest Dryas, BØlling and older Dryas).