Late Holocene changes in vegetation of the Mrągowo Lakeland (NE Poland) as registered in the pollen record from Lake Salęt

Abstract

Pol len anal y sis of sed i ments from the up per part of bot tom de pos its from Lake Salêt al lowed re con struc tion of main stages of the Late Ho lo cene veg e ta tion trans for ma tion in the Mr¹gowo Lake Dis trict (from ca. 3600 cal. years BC) and to cor re late some of these changes with im mi gra tion and eco nomic ac tiv ity of lo cal hu man groups. Sig nif i cant spread - ing of sec ond ary semi-nat u ral birch for est, de vel op ment of horn beam for est and in creas ing im por tance of anthropogenic open com mu ni ties were the most char ac ter is tic fea tures of veg e ta tion evo lu tion. A def i nite break down of elm took place be tween 2900 and 2500 cal. years BC, slightly af ter in creased con tri bu tion of birch in wood lands. Dis appear ance of ha zel around 1200 cal. years BC, ac com pa nied by ex pan sion of horn beam has been ob served and should be linked with ac tiv ity of the Z¹bie-Szestno type cul ture and the Lusatian cul ture tribes dur ing the Bronze Age, but not with a cli mate change. Con sid er able in ten si fi ca tion of set tle ment pro cesses re corded in the youn ger part of the Subatlantic chronozone was one of the im por tant rea sons that were re spon si ble for quick changes in for est struc ture. Strong and con tin ued de for es ta tion started as early as the end of the 10th cen tury AD and was sub stan tially in ten si fied in the first half of the 13th cen tury