高寒沙地2种锦鸡儿的根系分布

中间锦鸡儿和柠条锦鸡儿是共和盆地沙丘造林的主要树种。通过剖面法比较了2种锦鸡儿10年生人工林的不同级别的根系分布特征。结果表明:2种锦鸡儿均为深根系植物，深度达到1 m。中间锦鸡儿的根系生物量主要分布在0~60 cm。其中，粗根、中根和细根分别主要分布在0~30、0~60 cm和0~60 cm。然而，它的3个不同径级根系的长度分别主要分布在0~30、0~50 cm和0~60 cm。柠条锦鸡儿的根系生物量主要分布在0~90 cm。其中，粗根、中根和细根分别主要分布在0~60、0~60 cm和0~90 cm。然而，它的3个不同径级根系的长度分别主要分布在0~60、0~60 cm和0~70 cm。因此，中间锦鸡儿的根系相对较浅，适宜吸收降雨补充的浅层和中层土壤水分。柠条锦鸡儿的根系向更深的土壤中生长，吸收深层土壤水分。这反映了2种锦鸡儿对高寒沙地半干旱气候的适应差异。

Root Distribution of Two Species of Caragana in Alpine Sandy Land

Caragana intermedia and C.korshinskii are tow main shrubs used in the re-vegetation on sand dunes in Gonghe Basin.Root distribution characteristics of different types of two Caragana species were studied by profile method.The results showed that 10-years-old plantation of two species were deep-rooted,which was as deep as 1 m.The fresh and dry mass of C.intermedia distributed mainly in 0-60 cm,and the coarse roots,medium roots and fine roots distributed in 0-30,0-40 and 0-60 cm depths,respectively.However,the length of different root types distributed in 0-30,0-50 and 0-60 cm,respectively.The fresh and dry mass of C.korshinskii distributes mainly in 0-90 cm depth,and the coarse roots,medium roots and fine roots distributed in 0-60,0-60.and 0-90 cm,respectively.However,the length of different types of C.korshinskii roots distributed in 0-60,0-60 and 0-70 cm.Therefore,the relative shallower root system of C.inermedia was suitable to use soil water in shallow and medium depth;the root system of C.konshinskii grew to deeper depth to use deeper soil water,indicating the differences in the adaptation characteristics of two Caragana shrubs to semi-arid climate in alpine sandy land.