Water dynamics and physical characteristics of hydromorphic soils in southern Bačka

Abstract

Background and Purpose: The study presents basic types of hydromorphic soils in a protected area of middle part of the Danube alluvial plain in Vojvodina. The Danube is the largest river in the Republic of Serbia. This is the first river which itself created an alluvial plain through the Pannonian plain. Due to the mild decrease of river bed slope and lateral erosion, which is a characteristic of lowland rivers, it formed a large dry alluvial plain. It was formed during the Holocene by alternating action of fluvial, erosion and accumulation processes. Materials and Methods: In this s tudy, t h e following classes of hydromorphic soils in the protected area of alluvial plain of the river Danube were studied: undeveloped hydromorphic soils (fluvisol), semigley soils (humofluvisol) and gley soils (humogley and eugley). Four soil types were examined within the hydromorphic order of soils: fluvisol, humofluvisol, humogley and eugley. The measurements of groundwater level and of the water level of the Danube river were carried out twice a month during the growing season in the period of two years. The distance of piezometers from t h e Danube was also measured. By each piezometer, a pedological profile was established. Its external and internal morphology was described and soil samples were collected for laboratory testing. Laboratory examination of soil included analyses according to standard pedological methods. Results: The most important characteristics of the soils ar e presented in this s tudy. The hydrological and physical characteristics are particularly described, especially the dynamics of groundwater during the growing period in two years, granulometric composition, differential porosity and Darcy's coefficient. The average groundwater level related to the soil surface varied in fluvisol from 258 to 301 cm, in humofluvisol from 234 to 260 cm, in humogley from 142 to 167 cm, and eugley from 38 to 51 cm beneath soil surface. The amplitude of the groundwater level variation varied from 94 to 120 cm in fluvisol, 138 - 256 cm in humofluvisol, 105-134 cm in humogley and 43-55 cm in eugley. There was high correlation between groundwater level and the water level of the river Danube.