绿肥植物的化学组成对其氮素有效性的影响

THE AVAILABILITY OF NITROGEN OF GREEN MANURES IN RELATION TO THEIR CHEMICAL COMPOSITION

摘要:

绿肥作物,特别是豆科绿肥,不仅是土壤有机质的重要来源,更是作物氮素的良好给源.绿肥的后一作用,历来受到人们的重视.许多研究者研究了绿肥中氮素对当季作物的有效性以及影响氮素有效性的因素.已经知道,除土壤性质和作物种类外,绿肥作物的化学组成,特别是C/N比值和木质素含量是影响其氮素有效性(对当季作物)的关键因素.

Abstract:

The nitrogen balance and the availability of residual nitrogen of green manures in relation to their chemical composition were studied in pot and incubation experiments.Azovla,milk-vetch and common water hyacinth were used as green manures and labelled by the fertilization of (¹⁵NH₄)₂SO₄.Result obtained are summarized as follows:1.Although plant materials having lower C/N ratio usually give more available nitrogen and the C/N ratio of azolla was lower than that of milk-vetch,yet azolla contained high lignin about 20%,and consequently the percentage recovery of mitrogen by rice plant from azolIa was much lower than that from milk-vetch.