Among reclaimed valleys and canalised rivers of the Kurpiowski Sandr, the valley of Omulwia river is distinguished by relatively unchanged landscape and natural, strongly meandering river-bed of 15-20 m width. Its run is accompanied by zone of branched, picturesque, partly filled-with-water old-river beds. On the grounds of identification of the existing soils, plant communities and peat beds in the lines of 8 levelled transverse valley sections (fig. 2), the appearance of distinct, transverse ecological zonality related to the existing hydrological conditions, has been found. The distinguished zones differ in character of soils and vegetation as well as in the intensity of flood and ground feeding. In the area, directly adjacent to the river, being intensively flooded, the dominating type of habitat is silt-covered ground, generating alluvial heavy and medium, usually medium-deep (50-100 cm) formations. They occupy about 1/2 of valleys width. The zone of specific mads is situated at the nearest distance from the river. On both sides of this zone, the parallel bands of mineral-muck mads were found, being identified on the grounds of the presence of silt-originated moorsh in the upper layer up to 30 cm. In the marginal, usually higher situated parts of the valley, there are peatlands, supplied with ground water; they create a separate ecological zone, running like a band alongside both edges of the valley and fill the pockets, eroded in its mineral substratum, with peats. Shallow beds form alder and osier peats. In deeper cuttings of mineral substratum, there are beds of more complex structure with the share of sedge and rush peats and, in deeper initial levels, also of mossy peats. Between the zones of alluvial soils and the zone of peat soils, a zone of mineral-moorsh soils, built by peat-originated moorsh, has been additionally found. In alluvial zones, characterized by a rich microrelief, the communities of Magnocaricion, usually sedge (Caricetum gracilis) and reed canary grass and sedge-reed canary grass (Phalaridetum arundinaceae) are mainly found. They create a mosaic with the communities of Molinietalia order (Alopecuretum pratensis Valeriano-Filipenduletum), appearing on flat elevations. In peat zones, we find mainly communities of sedge (Ranunculo-Caricetum fuscae) and reed grass (Calamagrostietum neglectae), belonging to Caricion fuscae (nigrae). The areas of certain reclaimed and managed peatlands are overgrown with communities of cultivated meadows. Nature values of the valley were assessed, classifying it into 3 parts and identifying 4 most valuable fragments for closer protection (fig. 5). Zone of the river and near-river old beds, which is most valuable part of the valley from ecological viewpoint and is strongly differentiated from a viewpoint of hipsome- try, the habitat and phytosociology, should be a place of extensive economy; its protection should be a leading motive in case of planning any economic investments. On the other hand, intensive meadow management should be focused on the edge parts of the valley, especially in marginal, east zone of the valley on the areas of higher elevated peat soils, being drained by a large ditch, running parallelly to the valley edges.
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