Summary:

Sewage sludge, depending on its preparation and local conditions will still constitute waste material for storage or a product to be used in nature. Due to its fertilizer value, sludge originating from treatment process as its by-product may be used for fertilization or reclamation of green areas. Obviously, to be used in nature the sludge must be properly prepared in processes allowing for removal of toxic compounds, which might negatively affect the quality of crops cultivated on it.
Rational agricultural production bases on observing rules to improve soil fertility and its productivity through application of proper cultivation measures, including mineral and organic fertilization. Soils of Poland usually reveal poor abundance in organic matter and when more demanding plants are cultivated in them, the amount of humus decreases rapidly and they become nutrient impoverished. Farmyard manure is the most popular organic fertilizer used in agriculture. After the year 1990 farmyard production declined considerably due to reduced animal production and the currently used doses are insufficient to obtain good yields. Therefore it is necessary to seek new alternative sources of organic matter which might be safely used as an alternative fertilizer.
Alternatives to FYM fertilizers include various types of organic substances, such as plant wastes, composts or sewage sludge originating from sewage treatment plants. An apparent improvement in ecological awareness in the society favors the idea of using alternative sources of organic matter through natural utilization of wastes, which at the same time reduces their storage at landfills. This idea should be supported by new pro-ecological productive solutions assuming minimization of wastes and new rules governing their processing and utilization. The most natural direction of management of already existing waste products and sewage sludge, particularly containing organic matter is their biological use. Biological utilization of sewage sludge may be realized to a wide extent in agriculture but they may be also applied for organization and maintenance of green areas in cities and in recreational areas.