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Open access

Jacek Antonkiewicz and Jan Łabętowicz

Abstract

This monograph aims to present how arduously views on plant nutrition shaped over centuries and how the foundation of environmental knowledge concerning these issues was created. This publication also presents current problems and trends in studies concerning plant nutrition, showing their new dimension. This new dimension is determined, on one hand, by the need to feed the world population increasing in geometric progression, and on the other hand by growing environmental problems connected with intensification of agricultural production.

Open access

Magdalena Szymańska, Ewa Szara, Marian Korc and Jan Labętowicz

Abstract

The aim of this study was to determine the relationship between the efficiency of agricultural production and selected parameters of farms and data describing the flow of nutrients on the farms. An analysis model was developed for nitrogen management on farms specializing in livestock production. The study was conducted on 20 farms located in 12 municipalities of the Mazowieckie province in central Poland in 2009.2012. The model was developed using multiple linear regression analysis in accordance with the backward stepwise method. Based on the regression analysis, the farm parameters that did not determine the dependent variable were eliminated. In the end, there were 10 independent variables included in the model. The model indicates that the efficiency of nitrogen management, expressed in cereal units per 1 kg of nitrogen (CU·kg-1 N), is significantly affected by: crop rotation, the demand for purchasing animal feed, the intensity of livestock production, the nitrogen content of farmyard manure, the nitrogen doses applied in mineral and natural fertilizers, and nitrogen outflow from farms with the sale of plant and animal products. The developed model explains 70% of the variation in the coefficient of efficiency expressed in cereal units per 1 kg N.