Bogumiła Jędrzejewska, Department of Biogeography, Mammal Research Institute on „Two centuries of dominant tree species turnover in the old-growth forests of Białowieża”

The Centre of New Technologies invites to a seminar by

Bogumiła Jędrzejewska
Department of Biogeography, Mammal Research Institute
on
Two centuries of dominant tree species turnover in the old-growth forests of Białowieża

Venue: Centre of New Technologies, Banacha 2C, Lecture Hall 0142 (Ground floor)

Host: Marta Szulkin

Abstract:

 Old-growth forests of Białowieża National Park, the best-preserved remnants of the natural lowland forests in the temperate zone of Europe, have often been regarded as a model and a reference point for comparison with man-transformed, managed forests. Yet all kinds of forests have their history and all are subject to changes due to both natural and anthropogenic influences.

I have collated the archival data on the past forest inventories to analyze the species composition of the natural tree stands of Białowieża Primeval Forest during the last 2 centuries. Although the area of the old growth (that is treestands neither cut nor planted) shrunk dramatically during that period, the available data showed a manifest and consistent process of turnover in the dominating tree species, from pine Pinus sylvestris, through spruce Picea abies, lime Tilia cordata, to hornbeam Carpinus betulus (dominant at present in old-growth of Białowieża National Park). The detailed data on the age structure of tree populations (based on measurements on sample plots in 1889, the 1930s, 1948 and 1989), and the shifts of habitat niches occupied by given trees, elucidated the course of the expansion-dominance-decline cycles (or a part of that cycle) in some tree species. The candidate for the next successful species is maple Acer platanoides, which has recently gained strong numerical dominance among the natural regeneration of trees.

I will discuss the possible driving forces of the observed turnover of tree species, such as long-term climate change, the disappearance of forest fires, and recovery from the anthropogenic pressure in the past centuries. I will also report why those fairly quick changes in the species composition of natural tree stands of Białowieża Forest worried the foresters and botanists.