Tag Archives: mineral nitrogen

149-155 A. Arlauskienė, A. Šlepetienė, S. Maikštėnienė and D. Nemeikšienė
The variation of mobile humic acids and mineral nitrogen in the soil as affected by the use of perennial grasses for green manure
Abstract |
Full text PDF (155 KB)

The variation of mobile humic acids and mineral nitrogen in the soil as affected by the use of perennial grasses for green manure

A. Arlauskienė¹, A. Šlepetienė², S. Maikštėnienė¹ and D. Nemeikšienė¹

¹Joniškėlis Research Station of the Lithuanian Institute of Agriculture,Joniškėlis, LT–39301, Pasvalys distr., Lithuania; e-mail: joniskelio_lzi@post.omnitel.net
²Lithuanian Institute of Agriculture, Akademija, LT 58344, Kėdainiai distr., Lithuania;e-mail: alvyra@lzi.lt

Abstract:

The paper presents the findings of the experiments conducted on a clay loam gleyic Cambisol at the Lithuanian Institute of Agriculture’s Joniškėlis Research Station and the results of analyses done at LIA’s Laboratory of Chemical Research in 2007–2008. The tests were designed to establish the effects of the use of perennial grasses – red clover (Trifolium pratense L.), lucerne (Medicago sativa L.), their mixtures with festulolium (x Festulolium), pure festulolium and their biomass as green manure on the variation and migration of mobile humic acids and mineral nitrogen in the soil of organic farms. Experimental evidence indicated that the content of mobile humic acids depended little on the plant species, however, when mixed management of the aboveground mass of perennial grasses (herbage of the first cut is removed from the field; second and third cut herbage left for green manure) was used, it increased significantly compared with the treatment where herbage had been removed from the field. Before ploughing-in of perennial grasses, the content of Nmin. in the 0–30 cm soil layer was significantly reduced (by 18.3 and 10.1%) by the cultivation of red clover and lucerne in mixtures with festulolium, compared with pure crops of respective legumes. The averaged data suggest that the highest Nmin. content in the soil was recorded in the treatments where mixed management of herbage had been used compared with the treatments where herbage had been removed from the field. In late autumn, 2.5 months after herbage ploughing-in, Nmin. concentration in the –30 cm and 3–60 cm soil layers increased by 8.9–53.9%, 7.8–93.7%, compared with that present in the soil at the end of August. Significantly lower Nmin. concentration in the 0–30 cm soil layer was found after festulolium cultivation, compared with red clover, and its content was also the lowest in the deeper layer (30–60 cm). When the herbage of perennial grasses had been used as green manure by four–time mulching, Nmin concentration significantly increased in the topsoil layer (0–30 cm) by 23.1% and tended to increase in the deeper soil layer (30–60 cm) by 11.4%.

Key words:

, , ,