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J. Superson et al. 2010. The deforestation of loess uplands of SE Poland and its stages as documented by valley deposits
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The deforestation of loess uplands of SE Poland and its stages as
documented by valley deposits (case study: Bystra river valley,
Lublin Upland)
Józef Superson, Jan Reder and Wojciech Zgłobicki
Institute of Earth Sciences, Maria-Curie Sklodowska University, Lublin, Poland
Abstract
Agriculture developing in the loess uplands of SE Poland caused the reduction of woodland
areas, which resulted in an increased intensity of erosion processes. A greater amount of mineral
deposits was supplied to the bottoms of river valleys. The objective of this study is to link these
deposits with stages of prehistoric settlement and deforestation in the Bystra drainage basin.
Sediments stored in the valley bottom were analysed in details. Several phases of deforestation
related to human activity were described. An attempt to correlate changes of type,
characteristics and geochemistry of analysed sediments with stages of deforestation was made.
Keywords: deforestation, loess areas, Poland, valley deposits
1. Introduction
In loess areas, forests are the best form of land cover preventing soil erosion and gully erosion
(Rodzik et al. 2009). Agriculture developing in the loess uplands of SE Poland from as early as
the Neolithic caused the reduction of woodland areas, which resulted in an increased intensity of
erosion processes. In consequence, mainly as a result of gully erosion, a greater amount of
mineral deposits was supplied to the bottoms of river valleys. Favourable natural conditions, as
well as the long-term and multi-stage nature of erosion processes related to deforestation and
agricultural use of land, have caused the accumulation of thick series of deposits in the bottom
of valleys. They are represented by terrace deposits and alluvial fan deposits covering them
(Superson, Zglobicki 2005).
The objective of the study is to link these deposits with the archaeologically documented stages
of prehistoric settlement and deforestation in the Bystra drainage basin based on the findings of
archaeological research conducted so far and the authors’ own geomorphological studies.
Deposits filling the bottom of the Bystra valley may be used as a peculiar geoarchive
documenting the development stages of the environment in the area under study, including the
changes in the forest cover.
2. Research area and methods
Bystra is a small river flowing into the Vistula in the area where the latter breaks through the
upland belt of central Poland (Figure 1). The lower reaches of the Bystra drainage basin are
situated within the loess-covered meso-region, the Naleczow Plateau (Lublin Upland). One of
the Plateau’s characteristic features is the occurrence of the loess cover that is up to 30 m thick.
This meso-region is an undulating plateau with the highest elevations ranging from 180 to 220
m a.s.l. The Plateau is dissected by the valleys of the Bystra and its tributaries, up to 125 m a.s.l.
deep, as well as numerous trough-shaped valleys and a very dense network of gullies – up to 11
km·km -2 (Maruszczak 1973). The loess areas, from the Boreal period of the Holocene, were
Forest Landscapes and Global Change-New Frontiers in Management, Conservation and Restoration. Proceedings of the IUFRO Landscape Ecology
Working Group International Conference, September 21-27, 2010, Bragança, Portugal. J.C. Azevedo, M. Feliciano, J. Castro & M.A. Pinto (eds.)
2010, Instituto Politécnico de Bragança, Bragança, Portugal.