The authors present the results of research on the changes of the hydrolog-ical properties of sandy soil after applying the hydrogel ZEBA SP. Uniqueness of the absorbent is due to the fact that is obtained from maize corn starch and there-fore can be an alternative to the hydrogels offered in Poland.In the laboratory experience, in which pF curves of the soil were outlined with the different content of ZEBA SP absorbent was conducted, as well as experi-ence in vases was assumed determining the influence of different concentrations of preparation on changes of the soil moisture and the pace of the soil drying.Examinations showed, around preparation is giving the best effects in the concentration of the 0.5%. Such an amount of preparation: increased the effective and potential useful retention of the soil by the 17%; extended the time of drying of the soil from the state maximum to the minimal humidity from 14 up to 19 days in comparing with the soil without absorbent; increased the availability of the soil water for plants from 9 up to 20 days. ...
Because of more and more frequent droughts and observed climate changes, infrastructural investments in forest are at present targeted at increasing water resources, which is realized under the so-called small-scale water retention. Forest reservoirs located in Pomorze Forest District in the north-eastern Poland, which was selected for research, fits this trend. The constructed facilities were to reduce the indications of habitat dryness and to improve fire prevention. The investment consisting in building 14 objects of water melioration has changed water conditions in the research area. 12 oak dams, stone weir and an earth pond for amphibians have been built. As a result of the realized investment, the level of water has increased and problems with periodical flooding of forest habitats have occurred. At the beginning of 2012, observational and measuring wells were created to monitor all occurring changes of the soil water table. The received data can be useful in clarifying the causes for flooding and in possible suggestions to improve the existing water conditions. This paper presents the analysis of the influence of realized investments on the changes in the level of groundwater between 2012 and 2014. ...