No abstract

The eutrophication of surface waters is a natural process; however, anthropogenic activities significantly accelerate degradation processes. Most lakes in Poland and in the world belong to the poor and unsatisfactory water quality class. It is therefore necessary to limit negative anthropogenic impacts and introduce restoration methods, in particular those that are safe for the aquatic ecosystem. One of these is a pulverizing aeration Podsiadłowski method that uses only wind energy. The method allows for the moderate oxygenation of hypolimnion water, which maintains the oxygen conditions in the overlying water zone in the range of 0–1 mg O2·dm-1. The purpose of the work was to develop a new method of determining the efficiency of the aerator pulverization unit in the windy conditions of the lake. The method consists in determining the volumetric flow rates of water in the aerator pulverization unit, based on maximum hourly wind speeds. The pulverization efficiency in the conditions of Góreckie Lake was determined based on 6600 maximum hourly wind speeds in 2018. Based on the determined model, the theoretical performance of the machine was calculated, which in the conditions of Góreckie Lake in 2018 amounted to less than 79,000 m3 per year (nine months of the effective aerator operation).

Samołęskie Lake is situated in the Poznań Lakeland in Greater Poland Voivodeship, Szamotuły County, Wronki District. The lake adjoins a little village of Samołęż of about 500 residents. The glacial waterbody of over 30ha acreage is a typical tunnelvalley lake having a maximum depth of over 22 meters. It predominantly serves fishing and recreation purposes offering a beach and a sailing center. Near the coastline (not in the direct vicinity) there is a farmland. The objective of the dissertation was to assess the quality of Samołęskie Lake waters that was delivered based on the studies carried out in spring and summer, when the waterbody demonstrates excessive fertility. The studies covered the analysis of the basic physical and chemical parameters of the lake water. The measurement was carried out on a fortnight basis by means of a measurement apparatus such as the photometer and the Secchi disc. The collected results are presented with the use of figures later in this paper, whereas their in-depth analysis allowed to compile and formulate conclusions. The results of studies and analyses lay the foundations to state that the quality of Samołęskie Lake waters requires continuous monitoring and application of remedial and rehabilitation measures.

An important factor along with the availability of food is its quality. It depends, among other things, on the type of plant protection products used and the method of their application. This manuscript presents research on the possibility of using a shielded band sprayer in field onion cultivation. The shielded band spraying technology presented in this article is the subject of a patent application (application number P.428494-The prototype of the machine was produced in Poland in cooperation with the University of Life Sciences in Poznań). The research consisted in comparing the quantity and quality of the obtained crop, based on various methods of reducing the weed population. The research results indicate that the proposed shielded band spraying technology may affect the food quality (the active substance is not sprayed on onion plants) and profitability of farms (less use of plant protection products).

Lakes are one of most important freshwater ecosystems, playing significant role in functioning of nature and human economy. Swarzędzkie Lake is good example of ecosystem, which in last half-century was exposed to the influence of strong anthropopressure. Direct inflow of sewage with large number of biogens coming to the lake with water of inflows caused distinct disturbance of its functioning. In autumn 2011 restoration bagan on Swarzędzkie Lake for reduction of lake trophy and improvement of water quality. For achieving better and quicker effect, simultaneously combination of some methods was applied, among others method of oxygenation of overbottom water with help of pulverization aerator and method of precise inactivation of phosphorus in water depths. Characterization and analysis of improved coagulant dispenser applying active substance only during work of pulverization aerator is the aim of this thesis. Principle of dispenser work, its structure and location in pulverization aerator were explained. It was stated that introduction to water a factor initiating process of phosphorus inactivation causes significant reduction of mineral phosphorus in water and size of coagulant dose correlates with intensity of work of pulverization aerator with wind drive.

The quality of technical services is one of the main criteria for assessing the service processes of agricultural machinery, and it has a significant impact on the decision-making process when choosing a service provider. Technical service quality has a significant role in maintaining agricultural machinery in optimal technical condition, thus ensuring its high reliability and durability. The purpose of this study is to present a decision support method for choosing the right agricultural machinery service facility. The method is based on fuzzy inference. The choice of service workshop is based on decision criteria individually accepted by farmers (experts). The method was checked by way of research carried out among 25 farmers facing the choice of a service facility. The decision-making process allows for ranking the decision criteria and decision-makers. The results of the presented research can be used by farm owners and service companies to plan their development directions.

This paper describes the research aimed at developing an effective quality assessment method for potato tubers using neural image analysis techniques. Nowadays, the methods used to identify damage and diseases are time-consuming, require specialized knowledge, and often rely on subjective judgment. This study showed the use of the developed neural model as a tool supporting the evaluation of potato tubers during the sorting process in the storage room.

Waste management is one of the most important problems concerning contemporary civilization. The increase of the number of population and consumerism, cause producing different kinds of waste. Along with the economic progress and the technical progress, humanity became the largest producer of waste in nature. Segregation is still the biggest problem of selective collection of waste. The awareness and the knowledge of people in caring about the natural environment is growing. Unfortunately, many of them are not convinced to sort municipal waste. However, in making a decision about segregation, each of them could be influenced by other factors. The aim of this study was to collect detailed criteria which influence the decision about waste segregation among people not segregating the municipal waste. Then the main criteria were grouped and their influence on the global decision was shown. In this paper a method of the Analytical Hierarchization of the Process was used. Research was conducted among 50 randomly chosen respondents from Poland. The results of the research showed that the financial penalties and the possibility of reducing the payment for sorted municipal waste could increase the amount of people who segregate the municipal waste. Increasing the awareness of reducing the natural resources consuming is not as important criterion as two mentioned before.