The aim of this study was to determine the effect of the soil tillage system on soil enzymatic activity. The performed investigations, employing two soil tillage systems: classical (ploughing) and simplified (no-tillage), were carried out on Luvisols and Arenosols differing typologically, with regard to their kind and species. The activity of the following five enzymes was determined in soil samples: dehydrogenases, acid phosphatase, alkaline phosphatase, urease and protease. The applied enzymes tests turned out to be good indicators differentiating the examined soil objects depending on the employed tillage system. The employment of the simplified tillage system stimulated significantly the activity of the analysed enzymes irrespective of the soil type. This effect was particularly apparent in the top layer (0-10 cm) of the soil. An exceptionally wide range of activity was obtained for dehydrogenases indicating the usefulness of this group of enzymes for the evaluation of changes in the soil environment under the influence of the soil tillage system. The observed activity stimulation of the examined enzymes was accompanied by advantageous changes in soil chemical conditions.

The paper presents characterisation of the eco-chemical condition and potential threats to soils of goose farms on the basis of recent monitoring of a 15-year measuring cycle. It was demonstrated that the observed soil enzymatic inactivation progressing with years of investigations on the examined farms was significantly associated with a very high content of mineral nitrogen and available forms of phosphorus. A distinct tendency towards increased content of heavy metals in soils derived from these farms as well as in their direct neighbourhood observed with the passage of time poses a serious hazard to the environment

Changes in activity of amylase, cellulase, protease and dehydrogenase during biodegradation of petroleum contaminants were investigated in laboratory studies. Refinery soil polluted for a long time was modified by commercial biological preparation and natural biological preparation (prepared from this soil). These modifications did not influence cellulase and protease activity. Activity of amylase and dehydrogenase changed in these samples. In the sixth week the highest activity of dehydrogenase was noticed, especially in soil with commercial biological preparation. Modifications had a great influence on contaminants degradation. The highest elimination of TPH (20,4%) and heavy fractions (10,5%) took place in soil modified by commercial biological preparation. The highest PAH elimination was in soil with natural bacterial preparation

The aim of the presented investigations was to examine changes in the intensity of dehydrogenase and acid phosphatase activities as well as of the dynamics of selected groups of microorganisms in the soil under the cultivation of winter triticale following the application of the following seed dressings: (a.s.) flutriafol 2.5% + fludioxonil 2.5% in two doses and (a.s.) carboxin and tiuram. The experiment had a field character. The number of microorganisms (total bacteria, fungi, oligotrophic, copiotrophic and Azotobacter) was determined by the plate method on adequate agar substrates. Activity levels of the selected enzymes were defined using the spectrometrical method.

The obtained results indicate a change in the dehydrogenase and phoshatase activity in soil depending on the seed dressing applied in the experiment as well as at the date of investigations. The number of microorganisms in the soil underwent fluctuations depending on the developmental stage of triticale and the applied fungicide. The performed experiment demonstrated that counts of microorganisms in the soil underwent fluctuations depending on the developmental stage of triticale and the applied fungicide.

This study focused on the effect of heavy metal cobalt ions (at concentrations of 1–1000 ppm) on the development and enzymatic activity of four entomopathogenic fungi: Beauveria bassiana, Beauveria brongniartii, Isaria fumosorosea and Metarhizium robertsii, commonly used in biological plant protection. It was found that each of the tested species of fungi reacted individually to contact with the Co2+ ions at their various concentrations. Depending on the variants of the experiment carried out, there were changes in the development of the mycelia (mainly growth inhibition) and their morphological features (color and structure) in comparison to the control samples. Co2+ ions had a fungistatic effect on all fungal strains, whereas a fungicidal effect was noted at concentrations of 750 ppm and 1000 ppm against M. robertsii and I. fumosorosea, respectively. In addition, there was a discrepancy in enzymatic activity between the tested fungal species developing in the medium with varying concentrations of metal salt. The inhibitory effect of Co2+ ions on lipase production was observed in I. fumosorosea. Protease production was stimulated in B. bassiana at all Co2+ concentrations, whereas in M. robertsii this effect was noted at 1 ppm. The changing dynamics of extracellular fungal hydrolases, due to the action of Co2+ ions, may translate into the role of these microorganisms in the processes of insect pathogenesis. This work suggests that severe pollution of the environment by cobalt could be a restrictive factor for the development and pathogenicity of entomopathogenic fungi and must be taken into account for their successful application in biological plant protection.

The aim of the research was to assess the microbiological (number of heterotrophic bacteria, actinobacteria and moulds) and biochemical (urease and acid phosphatase activity) state of peat with the admixture of composts produced from sewage sludge. An additional aim of the research was to demonstrate the influence of those substrates on the morphological traits of scarlet sage (height, number and length of shoots, number of buds and inflorescences, greenness index (SPAD)). Composts produced from sewage sludge, wheat, maize and lupine straw were mixed with peat, where their percentage varied from 25% to 75%.

The substrate which included the composts applied in the experiment had a higher number of heterotrophic bacteria and a higher acid phosphatase activity level than the control substrate (peat). The multiplication of moulds and actinobacteria was more intensive than in the peat only in the combinations with K3 (sewage sludge 50%+sawdust 20%+ lupine straw 30%) and K4 (sewage sludge 50%+sawdust 20%+fresh maize straw 30%) composts, whereas the highest urease activity level was observed in the soils produced from K1 (sewage sludge 50%+sawdust 20%+white straw 30%) compost.

The most optimal development of plants was observed in the substrate with compost produced from wheat straw. Composts produced from municipal sewage sludge were found to be suitable for growing scarlet sage. However, their effect depends on the percentage of high peat in the substrate.

Badano wpływ osadu ściekowego na aktywność enzymatyczną pokrywy glebowej na terenie po otworowej kopalni siarki w celu oceny możliwości jego wykorzystania w leśno-łąkowej rekultywacji terenów Kopalni Siarki "Jeziórko". Wyniki, uzyskane po sześciu latach od zastosowanych zabiegów rekultywacyjnych wskazują, że osad ściekowy, dodany w odpowiedniej dawce, wpływał na ogól korzystnie na właściwości biochemiczne i chemiczne gleby. Oznacza to, że zastosowany osad może być brany pod uwagę, jako jeden ze środków służących do rekultywacji gruntów toksycznych.

The paper presents results of the research on the influence of sewage sludge on the enzymatic activity of the anthropogenic soil on the area of the former borehole sulphur-mine as well as· the effectiveness of sewage sludge utilization for forest-meadow reclamation of this ground.

The study makes an attempt to assess the impact of uncontrolled waste dumps on soil chemical and biochemical properties. Investigations were carried out on five waste disposal sites situated in the south-eastern outskirts or the city of Lublin. The samples of soils collected from the adjacent arabic land were used as reference material. In soils of four landfills, which were established relatively recently (lour to five years ago); several times higher activity of the examined enzymes (dehydrogcnascs, acid phosphatase, basic phosphatase, urcasc, protease) than in the soils from the adjacent cultivated land was determined. Opposite ti-ends were found in the case ofa waste dump established 20 years ago. The determined lack ofnegative influence or the examined waste dumps on the soil chemical and biochemical properties of the adjacent arabic land shows that the range or the contamination effect on the surrounding area was limited.

Exploited lubricants are dangerous contaminants because of their toxicity and low biodegradability. In this study, microbial culture active in exploited lubricant oil Mobil I was isolated and inoculated to sandy soil containing 0.5 g of contaminant per 100 g of dry soil. Microorganisms were used as free cells and immobilizate on wood chips, soil was also properly supplied with water and nutrients. The bioaugumantation seems to enhance biodegradation process. After 5 months, 93% of non-polar compounds were eliminated from soil containing immobilized biomass. Comparatively, in non-treated soil (control system) the contaminant elimination was at the level of 47%. Bacterial number in treated and non-treated soil was similar for about 3 months; however enzymatic activity (dehydrogenascs and hydrolascs) in control soil was much lower. Finally, after 5 months of treatment the content of bacteria active in contaminant decomposition in inoculated soil was 100-fold higher than in control system. Presumably, the main reason of low remediation results in non-treated soil seems to be low enzymatic activity of the biomass.

Bacterial, enzymatic and chemical analyses pointed to active microbiological mineralization and transformation of penguin excrements at "maritime Antarctic". The following physiological groups of bacteria were found: proteolitic, amonifying, nitrifying, lecithin degrading, Са3(Р04 ) 2 dissolving, chitin degrading and spore forming ones. The number of molds was not significant. The nitrate reducers and N2 — fixing bacteria were not detected. About 50% of С and N were volatilized during three weeks. Some parts of N — NH3 was oxidized to N — NO3 in surface layer of the soil. The content of P increased during degradation of penguin excrements. About 1/3 part of total organic carbon content in bird excrements residues was derived from chitin.