ANNA ORCZEWSKA

University of Silesia,
Faculty of Biology and Environmental Protection, Departament of Ecology;
Bankowa 9, 40-007 Katowice
e-mail: anna.orczewska@us.edu.pl

Description popularizing the research project

The offer of landscape architects is full of available services. The range includes inventory of the present condition, analyses of soil, exposure and light conditions, several versions of arrangement, actual construction, supervision and maintenance. Japanese gardens, English ones, landscape ones, formal ones, French ones, winter ones and water ones, all of them are available for a professional gardener. The effect is stunning. The list of species and varieties planted in one square meter is impressive. Yet still the most beautiful garden, designed according to the best landscape architecture academies will perish if it is not cared about for just one season. Weeds will infest it, meticulous cut will disappear and the style as well. It will be renaturalized.
If it were only possible to return the nature a forest according to a precise design of forest architects. They would plan the quantitative and qualitative composition of the woodland, they would calculate the amount of shrubs and their diameter and height as well. They would give the exact number of tufts of grass and sedge per square meter of the undergrowth. They would recommend a number of 1-, 2-, 3-, and 4-year-old seedlings of trees. They would present a layout of moss and mushrooms, the arrows would precisely show where lichen should be planted. Finally they would sprinkle their project here and there with dry leaves and it would be all. In the additional offer there would be cooperation with zoologists. Sounds easy. So why the recreating a forest starts and ends at the first of the mentioned points? It is so because a forest is not only species. You could say that it has the least to do with species. A forest is everything what lies in between. The best and the only forest architect is the forest itself. Ancient, unchanged by man, neighboring the recreated woodland. It is a bank of seeds of the highest quality and optimal composition for a given community. From there species spread, from soil bacteria to trees, and from springtails to roe deer, giving the forest its atmosphere.
The forest was before us, and it will be when are already gone... Our help is not essential.

Abstract

Due to drainage of damp and wet habitats, woodlands with black alder as the main component of a stand, have almost entirely disappeared from the landscape of western Europe. However, woods of such a type are still common in forested areas in some parts of Poland. The Lower Silesia and the northern part of the Opole Silesia are among such regions. Black alder is commonly planted there on the abandoned meadows, where mowing was neglected due to too damp conditions.
Lack of data on the rates of colonization of post-agricultural black alder plantations by woodland flora, was the reason of undertaking the research in such types of recent woods. The aim of the project, carried out in the northern part of the Opole Silesia (Oleśnica Plain) and Lower Silesia (Żmigród Valley), was to study the mechanisms and rates of the colonization process of the herb layer in alder woods, planted on abandoned meadows, by forest plant species.
The investigations allow to asses that the process of renaturalisation of the herb layer in post-agricultural woods is faster on more fertile and moist sites than in poorer and drier habitat conditions. Rates of migration of many forest species into alder plantations exceed those known from the literature, referring to forests of lower moisture and fertility. However, only a direct proximity of ancient woodlands, regarded as sources of diaspores of typical woodland flora, allows for effective colonization of the herb layer in recent woods by true forest species.