Efficiency of the photosynthetic apparatus in Cannabis sativa L. fertilized with sludge froma wastewater treatment plant and with phosphogypsum

Sewage sludge and phosphogypsum are by-products of wastewater treatment and phosphorus fertiliser production, respectively. Considering all known methods of their management, it seems rational to use these waste products in agriculture. While assimilating nutrients contained in sewage sludge or phosphogypsum, agricultural crops contribute to the recycling of these otherwise noxious materials. The objective of this study was to identify the effect of fertilization with sewage sludge and with phosphogypsum on selected physiological parameters that determine the efficiency of the photosynthetic apparatus in Cannabis sativa L. Field tests were conducted on three varieties of Cannabis sativa: Białobrzeskie, Tygra and Beniko. Plots were fertilized with sewage sludge as an equivalent of nitrogen nutrition in a dose of 170 kg N.ha-1 and with phosphogypsum applied in three doses: 100, 500 and 1000 kg.ha-1. The plants were subjected to physiological assays (relative content of chlorophyll and leaf area index) on three dates in 2014: 29 June (early development stage), 26 July (full development) and 20 September (final development stage). The study discusses the effect of fertilization with sewage sludge and phosphogypsum on the efficiency of the photosynthetic apparatus in Cannabis sativa

THE EFFECT OF SELECTED PHYSICAL AND CHEMICAL PARAMETERS ON MICROBIOLOGICAL STATUS OF THE VISTULA RIVER NEAR WARSAW

The types of organisms present in water reservoirs depend on water purity and biochemical processes that occur. Therefore, one of the methods of water quality assessment is to determine its condition by determining the biological indicators, including microbiological parameters. The aim of the experiment presented in this paper was to investigate the effects of selected physical and chemical parameters of water samples from the Vistula River on the microbiological status of water. The experiment was conducted in water samples collected in the central part of the Vistula River in Warsaw. The analyses of selected parameters were performed once a month throughout the year. Microbiological tests included: number of nitrogen fixing bacteria, MPN nitrifying bacteria, MPN sulfate-reducing bacteria. Physical and chemical parameters such as temperature, pH and total nitrogen content were determined in water samples. The results showed a correlation between temperature, pH and microbiological parameters. However, there was no significant correlation between the number of tested microorganisms and the concentration of total nitrogen in water samples