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引言人工草地植物学成分的变化与时间并无必然的函数关系,但某些阔叶草类变化形式通常随着草地的发育而发生(Morrison,1979)。种植的牧草种类的比例自播种后逐年下降而自生的杂草逐年增加。最初侵入低地黑麦草地的植物是早熟禾种类(普通早熟禾Poa triviatis L.和少量的早熟禾Poaannua L.)。
INTRODUCTION Changes in botanical composition of artificial grassland are not necessarily functionally dependent on time, but some broadleaf grassland changes usually occur with grassland development (Morrison, 1979). The proportion of the species of forages grown decreases year by year after seeding and annuals of weeds increase year by year. The plants that originally invaded the lowland ryegrass are Poa trivialis (Poa triviatis L. and a small amount of Poaannua L.).