Content of Organic Carbon and Nitrogen as Well as Root Mass in Meadow Soils Under a Combined Slope and Flood Irrigation System

Abstract

The aim of the present research was to determine the effect of long-term irrigation of grasslands on the content of organic carbon and nitrogen as well as on root mass in meadow soils. The research involved the Podlesie Czersk meadow complex unique in the Central Europe, under a combined slope and flood irrigation system. The system has been operating since 1850. In the complex investigated, three areas were selected: Kamienna, Podlesie and Cegielnia. From each area, Brunic Arenosols were sampled from the following horizons: Ad, AEes and ABv. From those horizons, there were also sampled soil monoliths together with root systems. The soil samples were assayed for the total organic carbon (TOC), total nitrogen (Nt) and root mass. It was demonstrated that horizon AEes showed the highest content of organic carbon and nitrogen, as compared with the other horizons, with a relatively low value of ratio TOC/Nt. The meadow sward root mass was, on the other hand, highest in horizon Ad, which does not positively correlate with the total organic carbon (TOC) and total nitrogen (Nt) in that layer. Drawing on the results, one can observe that such relationships are a result of permanently irrigated meadows applying a combined slope and flood irrigation system for the period of 150 years.