An impact of municipal sewage sludge and wheaten straw on some indicators of soil fertility

In a two-factor pot experiment the impact of applied diverse doses of municipal sewage sludge and equal dose of wheaten straw, with and without supplemental mineral N and NPK fertilization, on some fertility properties of soil was assessed. The soil used in the experiment was acid brown incomplete soil (good rye complex). The grass - Festulolium - was the test plant, harvested four times and in the second year - common sunflower and blue phacelia. After the harvest of phacelia, the pH (in 1 M KG), the content of total nitrogen, total carbon and the available forms of P, K and Mg were analyzed. Fertilization with sewage sludge and straw failed to have a significant influence on the change of the soil pH. However, all doses of sewage sludge + straw, in comparison with the control, significantly increased the content of total carbon (from 31.8 to 37.8%) and total nitrogen (from 34.3 to 52.2%) in the soil. There was significantly more phosphorus available in the soil from all the objects with sewage sludge and straw than in the soil from the control object (from 8.2 to 21.6%), while the content of potassium was higher only in the soil from the object with 1.5% of sewage sludge + straw and magnesium at the highest dose of sewage sludge. The mineral N and NPK fertilization, used against the background of sewage sludge and straw, did not have asignificant impact on the shaping of the analyzed soil fertility indicators

The impact of composts prepared from different organic waste on the total number of soil microorganisms

In a two-factor pot experiment impact of two doses of six types of composts prepared from the municipal sewage sludge with an addition of canteen waste, wheat straw and cocoa husk on the total number of bacteria, actinomycetes and fungi in the soil were exmined. The light soil used in the experiment was taken from the Ap level of an arable field. On all the objects with composts there was mineral NPK fertilization applied, the control object was fertilized with the NPK only. The test plant was grass Festulolium which was harvested three times and after the third cut the samples of the soil were taken for microbiological analyses. The conducted research shows that the number of microorganisms in soil was dependent on the dose and the type of the compost. The second dose of the compost, in comparison with the control object, in most composts considerably increased the number of bacteria and the first dose increased the number of actinomycetes. However, the number of fungi, in most cases, with both doses of composts, was lower than in the soil from the control object. The highest number of bacteria was noticed on the object with the co-most prepared from 35% sewage sludge + 35% canteen waste + 30% straw and actinomycetes on the object with the compost prepared from 35% sewage sludge + 35% canteen waste + 30% cocoa husk. The development of the soil fungi was restrained in the highest degree by the first dose of the compost prepared from 35% sewage sludge + 35% canteen waste + 15% straw + 15% cocoa husk and by the second dose of the compost prepared from 70% sewage sludge + 30% straw

Ocena właściwości fizycznych, chemicznych i energetycznych osadów pochodzących z oczyszczalni ścieków przemysłowych i komunalnych

The work presents physical, chemical and energetic properties of sludge from industrial and municipal sewage treatment plant in West Pomeranian Voivodeship. Among many macronutrients, sludge contains much of the following: nitrogen, phosphorus, calcium and magnesium, but little potassium. Total content of heavy metals (Cd, Cr, Cu, Mn, Ni, Pb, Hg, Zn) was lower than norms admitting sludge for natural, including agricultural use, presented in the Order of Ministry of the Environment14. Much content differentiation of particular sludge components indicates on the necessity to analyze each portion before its use. The kind of sludge (municipal, industrial) and the way of processing (thickening, drainage, drying) is embodied in differentiation in the content of organic dry matter and total organic carbon. Heat of combustion and calorific value of analyzed sludge oscillates in a very wide scope and the lowest value of indexes were achieved for dried municipal and industrial sludge, whilst higher for thickened municipal sludge and drained one. Sludge, the one after initial thermal processing (i.e. drying) can be used as renewable source of energy. Pearson's linear correlation analysis of sludge has show significant positive linear dependence between calorific value and organic dry matter content as well as total content of carbon and nitrogen for all analyzed kinds of sludge.W pracy przedstawiono właściwości fizyczne, chemiczne i energetyczne osadów pochodzących z oczyszczalni ścieków przemysłu spożywczego i komunalnych województwa zachodniopomorskiego. Spośród makro-składników osady ściekowe zawierały dużo: azotu, fosforu, wapnia i magnezu, a mało potasu. Całkowita zawartość metali ciężkich (Cd, Cr, Cu, Mn, Ni, Pb, Hg, Zn) była mniejsza od norm dopuszczających osady do przyrodniczego, w tym rolniczego wykorzystania, przedstawionych w Rozporządzeniu MŚ. Znaczne zróżnicowanie zawartości poszczególnych składników w osadach wskazuje na konieczność analizowania każdej partii przed ich wykorzystaniem. Rodzaj osadów (z przemysłu spożywczego, komunalne) i sposób ich przerobu (zagęszczanie, odwadnianie, suszenie) znajdowało odzwierciedlenie w zróżnicowaniu zawartości suchej masy organicznej i węgla całkowitego. Ciepło spalania i wartość opałowa analizowanych osadów ściekowych wahała się w bardzo szerokim zakresie i najniższe wartości tych wskaźników uzyskano w przypadku osadu przemysłowego i komunalnego po suszeniu, a wyższe dla osadu komunalnego zagęszczonego oraz odwodnionych. Osady, te po wstępnej termicznej przeróbce (np. suszeniu) mogą być wykorzystywane jako odnawialne źródło energii. Analiza korelacji prostoliniowej Pearsona osadów ściekowych wykazała istotne dodatnie prostoliniowe zależności między wartością opałową a zawartością suchej masy organicznej oraz całkowitą zawartością węgla i azotu dla wszystkich badanych rodzajów osadów ściekowych

The impact of composts prepared from different organic waste on the total number of soil microorganisms

In a two-factor pot experiment impact of two doses of six types of composts prepared from the municipal sewage sludge with an addition of canteen waste, wheat straw and cocoa husk on the total number of bacteria, actinomycetes and fungi in the soil were exmined. The light soil used in the experiment was taken from the Ap level of an arable field. On all the objects with composts there was mineral NPK fertilization applied, the control object was fertilized with the NPK only. The test plant was grass Festulolium which was harvested three times and after the third cut the samples of the soil were taken for microbiological analyses. The conducted research shows that the number of microorganisms in soil was dependent on the dose and the type of the compost. The second dose of the compost, in comparison with the control object, in most composts considerably increased the number of bacteria and the first dose increased the number of actinomycetes. However, the number of fungi, in most cases, with both doses of composts, was lower than in the soil from the control object. The highest number of bacteria was noticed on the object with the co-most prepared from 35% sewage sludge + 35% canteen waste + 30% straw and actinomycetes on the object with the compost prepared from 35% sewage sludge + 35% canteen waste + 30% cocoa husk. The development of the soil fungi was restrained in the highest degree by the first dose of the compost prepared from 35% sewage sludge + 35% canteen waste + 15% straw + 15% cocoa husk and by the second dose of the compost prepared from 70% sewage sludge + 30% straw