作　　者： ; ;

机构地区： 甘肃草原生态研究所

出　　处： 《草业学报》 1995年第2期51-57,共7页

摘　　要： 定位调查河西走廊三种盐化草地地下生物量随时空分布的规律表明：１）在垂直剖面中，海韭菜、小灯心草和芦苇＋赖草草地根系均呈“Ｔ’型。海韭菜草地的根量在３０～４０ｃｍ处有一增大，与芦苇在该层产生水平根茎有关；小灯心草草地地表根系极丰富，０～１０ｃｍ与１０～２０ｃｍ层的根量比达５．０；而芦苇＋赖草草地的构成种简单，地下生物量较前两个草地为少；２）三种草地地下生物量随土壤深度的关系均可用非线性函数描述，其最佳模型为：海韭菜草地：Ｙ＝２３４．７１６＋２３５４４．５４２／ｘ（ｒ＝０．９７５Ｆ＝２４５．９５）ｘ∈（０～５０ｃｍ）；小灯心草草地：Ｙ＝１７９．３８６×ｅ２５．０４／ｘ（ｒ＝０．９７８Ｆ＝２７９．２０９）ｘ∈（０～５０ｃｍ）；芦苇＋赖草草地：Ｙ＝３６．００１＋２３７９．５７２／ｘ（ｒ＝０．９４７Ｆ＝１３８．７９７）ｘ∈（０～６０ｃｍ〕；３）以上三种草地的活根量均在生长季未达最大，分别占剖面中相对含量的９０．９２％，９４．７％和９０．１７／；表层根系量大，非常活跃，海韭菜草地表层土壤活根量波动在３２．２５％～４５．１８％，死根量波动于３２．３２％～５１．２％；小灯心草草地表层活根和死根量波动较大，于２９．６８％～６? The distributional tcgularity of underground biomass with time and space in the three type of salinizedswards was measured in Hcxi Corridor.The results indicated that 1)Observed from the soil profile, the distribution of the underground biomase,took a shape of‘T’.Thebiomass drastically abounded at 30～40cm due to the growing reed rhizomes at this layer in Triglochimmaritimum sward. In Juncus bofonius sward the root system was abundant at the top layer and the root ratio of0～10cm to 10～20cm is 5.0.The underground biomass in Phragmite communis+Leymux dasystachys swardswas relatively poor because of the fewer species in the sward than those in the other swards.2) The distributional features of the underground biomass observed could be fitted with non linearfunctions, the results of Darameter estimation were as follows:T.martimum Sward:Y=234.716+23544.542/x (r=0.975 F=245.95)x∈(0～50cm)J.bofonius Sward:Y=179.386×e25.04/x r=0. 978 F=279. 209)X∈(0～50cm)P.communis+Leymus dasystechys Sward:Y=36. 001+2379. 572/x(r=0.947 F=138.797)x∈(0～60cm 3)The living roots of above swardS reached to the maxim um at end of growing season and relativeamount is 90.92%,94.7% and 90.17% for T.martimum sward,J.bofonius sward,P.communis +L.dasystechys sward respectively.The roots at top layers were aboud nat and active. The variation of therelative amount for living roots at top layers was 32.25%～45.18%,29.68%～63.43%,25.07%～42.90% respectively for above swards.In contrast the variation for dead rcots was 32. 32%～51.2%,37.18%～74.45%and 25.0%～41.67% respectively.In conclusion the root types and distributionalfeatures of the species in the comm unity were the factors that infl uence the distribution of undergroundbiomass of sward.

关 键 词： 地下生物量 小灯心草 河西走廊 盐化草地

领　　域： [农业科学] [农业科学] [农业科学]