investigation of litter quality and aerial organs and their effect on soil characteristics of four rangeland species(case study: hamand absard)

this study investigates the relationship between litter quality and aerial parts of plant on c, n, k, p and c/n ratio of soil in four rangeland species including agropyron intermedium, bromus tomentellus, eurotia ceratoides and kochia prostrata. after recognizing the sites of these species in hamand absard located in 65 km of northern tehran, at the end of growing season, samples of litter, aerial part of plants and soil were taken using systematic- random method. for this purpose, five transects, each of l00 m length and 50 m spacing were taken. two plots in each transect with an area of 1 m2 were established. in each plot, soil samples under plants and without plant area (control samples) at depth of 0-30 cm were taken. the c, n, p, k, ec, ph and texture of samples were analyzed in laboratory. analysis of variance, dunnett's test and t-student test were applied to the data. results show that in the aerial part of plant, c and c/n ratio of agropyron intermedium and p, k and n of kochia prostrata are higher than other species. in case of litter, c, k and c/n of eurotia ceratoides and n and p of kochia prostrata showed higher values. however the results of soil samples show that c of agropyron intermedium, n and c/n of kochia prostrata and k of bromus tomentellus are higher than other species. totally, kochia prostrata showed the best litter quality, decomposition rate and effects on soil.