| Summary: | This paper presents the results of research on changes in weed communities of stubble fields of the Piotrków Plain (see W a r c h o l i ń s k a, 1994 - Figure 1) which took place during the period between 1971 and 1972 and between 1992 and 1993. On the basis of 30 phytosociological records, taken in 24 localities (Figure 1) in the years of 1971 and 1972, 3 associations were distinguished (Tables I-III, see W a r c h o l i ń s k a, 1974): Centunculo-Anthoceretum punctati, Hyperico-Spergularietum rubrae and Herniario-Polycnemetum. According to the repeated listing carried out in the years of 1992 and 1993 the changes in the communities of the above-mentioned items were stated. The comparison of the present state of these communities with their state of 22 years ago allowed to note that the analyzed agrophytocoenoses of stubble fields got impoverished due to progressive anthropopressure (Tables I-IV, Figure 2).
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