911查询·英语单词
1. The following main conclusions are drawn from the present investigations:(1)The root system of T. tschonoshii is simple, with few fine roots and root hairs in mature zone; compared with those of Erigeron annuus, Conyza Canadensis, Conyza bonariensis and Aster subulatus, the root system of T. schonoshii is characterized by its less surface area, root volume and project area, together with its shorter total root length, which reveals the weak abilities in its absorbing water and mineral elements.(2)The anatomical and morphological characteristics of leaves and steams, chlorophyll content, photosynthesis, stomatal density and location on leaf epidermis indicate that T.
调查发现，延龄草根系不发达，平均直径较一般植物的粗，但是缺乏细根，而且成熟区根毛极为稀少，延龄草的根系总长度、总体积、表面积、突出面积等比一年蓬、小飞蓬、野塘篙和钻形紫苑等草本植物的明显要小，反映出延龄草吸收水份和矿质元素的能力相对较弱；延龄草茎和叶片解剖、光合作用特点、叶绿素含量、叶片气孔密度和分布位置等反映出该种是一种典型的阴生植物，不耐水湿条件强烈变化的环境。