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Summary Tapeworms parasitize at sites that are important for the management of micronutrients, including zinc. Therefore, it has been hypothesized that tapeworms will significantly affect the excretion of zinc in the feces of a host. The aim of this work was to evaluate the effects that tapeworms have on the excretion of zinc in the feces of the host. Rats were divided into 4 groups: groups 0T and MT (infected with Hymenolepis diminuta (Rudolphi, 1819)) and groups 00 and M0 (uninfected). The experimental groups (M0 and MT) were fed a standard rodent compound feed (ST-1) with added zinc lactate; the daily zinc intake was 20.5 mg. The control groups (00 and 0T) were fed only ST-1 with 1.75 mg of added Zn per day. For six weeks, the amount of consumed feed was recorded and fecal samples were taken. The samples were then analyzed by optical emission spectrometry (ICP-OES), and levels of excreted zinc were subsequently calculated as a percentage. The most signifi cant difference in zinc excretion levels between the experimental groups was observed in the third week, when rats infected with tapeworms (MT) excreted substantially lower levels of zinc than did uninfected rats (M0). This difference amounted to 28.36 % (p

In the Czech Republic, there are many contaminated agricultural soils due to anthropogenic activity and geogenic origin. The contaminated biomass of plants grown on the contaminated soils needs to be appropriately disposed of to prevent the re-releace of heavy metals into the environment. One way of processing contaminated biomass is pyrolysis, where the heavy metals are concentrated in biochar (active coal). This can be applied to soil where it improves the physical properties. The aim of the work was to observe the effect of temperature and the type of biomass grown on contaminated soils from a locality Příbram on the specific surface area, yield and mechanic resistance of active coal.

Soil contamination by risk elements is a serious problem. There are available remediation methods, using plants to remove these elements from soil. Plants for our experiments were grown on contaminated soil of Příbram area. Biomass of these plants was used to prepare biochar, which could be used then as a soil additive and due to its characteristics, can be able to immobilize risk elements in soil. The experiment was focused on the biochar preparation. There was observed the effect of the type of biomass and the final temperature on specific surface area and yield of biochar: properties limit its application as a soil additive. While the final temperature increased, the specific surface area increased and the yield of biochar decrease. The highest surface area was found at biochar from wood mixture.