The research issue focuses on potential interception, which is the maximum amount of water that can be stored on plant surface. Tests under controlled conditions remain the best way to enhance knowledge on interception determinants in forest communities. Such tests can provide data for identification of mathematical models based on ecological criteria.
The study presented in this paper concerned tree interception under simulated rain in a range from 2 to 11 mm/h. To perform the experiment a set of sprinklers was designed and built. The study included two deciduous species: beech (Fagus sylvatica L.) and oak (Quercus robur L.).
Descriptive characteristic and nonlinear estimation were suggested for the obtained data. Interdependence of potential interception, the intensity of rain and the size of raindrops were described using exponential equation.
The intensity and drop size of simulated rainfall significantly influence the obtained values of potential interception. Data analysis shows a decrease of interception value with an increase of intensity of simulated rainfall for both analysed species. Every run of the experiment that differed in the intensity and size of raindrops reached an individual level of potential interception and time needed to realize it.
The formation of ability of plants to intercept water depends both on the dynamics and the time of spraying.
Despite a long-term reduction trend, the potato production in Poland compared to EU countries is still very high. Therefore, the aim of the paper was to investigate the impact of mechanical damages and light for various genotypes on glycoalkaloids accumulation. Glycoalkaloids are toxic steroid glycosides that naturally occur in the family of Solanaceae. According to many authors, their presence in plants is related to resistance to a physiological stress inflicted by mechanical damages and infections caused by some microorganisms and insects. The TGA content above 200 mg∙kg−1 in a fresh mass of potatoes is an upper limit that guarantees health safety of food. Studies were carried out on 28 potato cultivars divided into 4 groups. The studies that were carried out after harvesting and after 5 months of storage in the experimental storage room in the temperature of 8°C showed an impact of damages and exposition to light of potato tubers on the content of glycoalkaloids.
A modern model of agriculture is based on three orders - organic, social and economic. An attempt was made in this paper to apply cluster analysis for assessment of economic and organic sustainability of organic farms. Factors that statistically influenced a decision on which farms should be recognised as sustainable were indicated. Analyses allow the following conclusion: 1) in organic farming, animal production including cattle breeding and rearing must be based on a high acreage of permanent grasslands; 2) neither the performed production processes nor the level of their automation rate or the level of organic balance do not decide on the production effectiveness, but factors of the surrounding including social factors.
The modern agriculture model is a model based on the principles of sustainable development, i.e. protecting the environment and the cultural landscape on the one hand, and on the other, ensuring adequate income for residents. It is based on three orders: ecological, social and economic. This paper attempts to use cluster analysis to assess the economic and ecological sustainability of organic farms. It also indicates the factors that statistically influenced the assessment of a farm as sustainable, or not. The first part of the work is dedicated to the characteristics of the problem and the methodology of research and analysis. The second part contains the results of the research and discusses them.