The aim of this study is to show the influence of oak admixtures in Scots pine stands on the properties of the surface humus accumulation horizons in forest soils formed of poor sandy parent material. In addition, differences in the floristic composition, shaping in pine stands of varying oak admixtures was analyzed. The study involved 30 plots which were located in the forest districts in the Polish lowlands. The selected areas were characterized by similar parent material. Three groups of study area (10 plots each) were specified: 1) group consisted of pine stands with no added species, 2) group consisted of pine with 10.20% share of oak, 3) group consisted of pine stands with single oak in the species composition. The positive impact of the admixture of oak in pine stands results in an increase in soil microbial activity. More favorable bio-physico-chemical properties of humus layers in stands supplemented with an admixture of oak are reflected in the greater abundance of forest undergrowth.
The aim of this study was to determine the enzymatic activity (dehydrogenase and urease) in trophically diverse Gleysols. Efforts to establish the relationship between enzymatic activity and physico-chemical properties of various subtypes of Gleysols were attempted. Dehydrogenase activity was best correlated with carbon content and acidity among the studied properties of soils. Urease activity was correlated with the reaction pf soil. Enzyme activity differentiates subtypes of Gleysols, which are characterized by a different type of soil humus. The dehydrogenase activity was higher in gleysols with peat or muck of swamp habitats. The opposite trend was found in the urease activity. The urease activity was the highest in the gleysols without organic matter. The studies showed that enzymatic activity is closely related to the type of accumulated organic matter and at the same time with species variety of plant communities..
The aim of this study was to determine the enzymatic activity (dehydrogenase and urease) in trophically diverse Brunic Arenosols and Cambisols. Efforts to establish the relationship between enzymatic activity and physico-chemical properties of various subtypes of Brunic Arenosols and Cambisols were attempted. Another aim was to determine the effect of vegetation on the properties of soil surface levels. The study was conducted on 94 plots located in nature reserves and national parks in the Polish lowland area. Dehydrogenase activity and urease showed large variations in the subtypes of the distinguished Brunic Arenosols and Cambisols. Dehydrogenases and urease activity in surface layers of fresh humus of Cambisols and Brunic Arenosols was strongly associated with the plants. This is confirmed by the relationship between the enzymatic activity and the type of accumulated humus substances, the ratio of carbon to nitrogen and humus horizons reaction.
Taking into account the progressive degradation of soils it is important to assess their quality. Soil quality depends on a large number of physical, chemical, biological and biochemical properties. In the publications available, there are presented three approaches regarding the use of soil properties to estimate soil quality: (1) the use of individual properties, (2) the use of simple indexes and (3) the use of complex indexes derived from combinations of different properties. The purpose of this study was to investigate the possibility to use enzymes as indicators of forest soil quality. Experimental plots (43) were located in central Poland. The study was carried out in a number of diverse fresh forest sites. To assess the quality of forest soils dehydrogenase and urease activity and the degree of base saturation were used. One of the final conclusions point out that enzymatic activity indicates current site condition as well as the changes that occur in soil better than soil physical and chemical properties. In other words, in comparison to soil enzymatic activity, soil physico-chemical properties constitute a less sensitive indicator of soil changes.
The aim of this study was to assess the condition of soil after serpentine fertilisation by determining the activity of phosphatase and some physicochemical properties of soil. The study was conducted in southern Poland in the Wisła Forest District (49°8’12.92N 18°58’56.36E). The following variants: C - control - no fertiliser; S - ground serpentinite; SN - serpentinite + nitrogen; SP - ground serpentinite + P; SNP - ground serpentinite + NP; SNPK - ground serpentinite + NP (as above) + K. Fertilisation of serpentinite stimulates the activity of phosphatase in soil under spruce stands. The positive impact is reflected in the organic horizon. Less activity was noted in the humus-mineral horizon (AE) in all the fertiliser combinations three years after the fertilisation. Fertilisation of serpentinite improves the chemical properties - pH was increased, reduction of molar ratio of exchangeable calcium to magnesium form was noted.
The alkalisation of soil is a common phenomenon in forest ground nurseries. Liming, inadequate fertilisation and the use of hard water for irrigation are the main reasons for this alkalisation. The aim of this study was to investigate the effect of fertilisation with aluminium sulphate on soil pH, the activity of selected soil enzymes, efficiency as well as the growth parameters of pine seedlings.
The study was conducted in a forest nursery, on a plot with soil pH 6.4 in water and 5.9 in 1M KCl. Such a pH is not conducive to the production of conifer seedlings, particularly pines. Two different doses of aluminium sulphate fertiliser were applied: 740 kg ha-1 and 1110 kg ha-1.
Both doses significantly reduced the soil pH, whereas soil enzyme activity did not change. The lower dose had a positive impact on the growth parameters of pine seedlings, while the higher dose led to their deterioration. We observed statistically significant differences in average primary and lateral root lengths, number of short roots, and thickness of the neck root of seedlings. One- and 2-year-old seedlings did not show symptoms of nutrient deficiency and neither did concentrations of the investigated macronutrients and selected micronutrients in needles indicate such. After applying the higher fertiliser dose, we observed a favourable change in the composition of mycorrhizae. Out of the potential seedling pathogens we found Cylindrocarpon spp., Fusarium spp.,Phytophthora spp., Pythium spp. and Rhizoctonia solani of which the most frequent were Fusarium oxysporom, Pythium spp. and R. solani. Their occurrence frequency differed between the treatments used in this experiment.
This study confirms the positive effects of a low aluminium dose on the performance and growth parameters of pine seedlings. However, on the basis of the conducted experiments, it is difficult to say, whether this positive effect is due to a direct action of aluminium on the seedlings or rather an indirect effect caused by lowering the soil pH, which in tum impacts on mycorrhizae composition and hence pathogen development.