摘要:The aim of the present study is to evaluate the long-term effects of long-term piggery effluent application on semi-natural grassland ecotop-phytotop changes (above- and below-ground phytomass production, and carbon and nitrogen allocation in grassland communities) in relation to changes (or variability) in topsoil properties. Analysis of phytomass distribution in piggery effluent irrigated grassland communities showed that dry biomass yield varied from 1.7−5.3 t ha-1. Variability in soil and plant cover created a unique and highly unpredictable site specific system, where long-term anthropogenic influences established successor communities with specific characteristics of above- and below-ground biomass distribution. These characteristics depend more on grassland communities than on soil chemical properties. Families of grasses (Poaceae) dominated the surveyed communities and accumulated most carbon and least nitrogen, while legumes accumulated most nitrogen and lignin and least carbon. Carbon concentrations in above-ground biomass had minor variations, while accumulation of nitrogen was strongly influenced by species diversity (r = 0.94, n = 10, p <0.001) and production of above-ground biomass