Quantification of the relationship between root parameters and soil macropore parameters under different land use systems in Retisol

The study aimed to quantify the relationship between root parameters and soil macropore characteristics in two soil layers of Retisol from a hilly landscape in Western Lithuania, as influenced by different land use systems. The decreases in root volume and root length density were dependent on land use and soil depth. The values of root length density and root volume at 0-20 cm depth tended to decrease in the following order: grassland > forest > arable land under conventional tillage. The highest volume in the framework of macropores was recorded for medium-size pores under arable land (3.02%), for fine pores (2.56%) in forest soil and very fine pores in grassland soil (below 1.19%) at the 0-10 cm soil depth, while at 10-20 cm soil depth, the coarse macropores dominated in the arable land system (below 1.41%). Root length density, root volume and the volume of very fine macropores had close relationships (p < 0.01, r = 0.91 and r = 0.68, respectively) under different land use at 0-20 cm depth. In Retisol, the roots were concentrated at 0-10 cm soil depth, and their volume was higher compared to the 10-20 cm depth. Plant roots increased the volume of very fine macropores in all land use systems, within the entire 0-20 cm soil depth.