黄河源区褐鳞苔草的固沙生物学特性

发布时间：2019-04-16 17:23

【摘要】：褐鳞苔草(Carex brunnescens)是黄河源区(玛曲)沙漠化草地具有较强固沙能力的先锋植物,对维护玛曲高寒草地生态系统稳定性有重要作用。为了揭示褐鳞苔草固沙的生物学特征,本研究在野外观测了其物候学特征,地上和地下器官生长进程以及地下器官形态学特征。结果表明,褐鳞苔草返青早,生育期较长,具有二次开花和结果的生长特性。褐鳞苔草单株叶宽、单株叶长、单株叶片数量、群落密度、群落盖度和群落叶片密度从展叶期-果实成熟期-黄枯期呈显著增加而后趋于稳定;而单株叶丛高度、单株叶面积和群落叶片面积呈显著增加而后减小的趋势。褐鳞苔草地下茎(水平茎和垂直茎)和根系适宜生存的沙层深度为0-60cm。不同沙层深度(0-20、20-40和40-60cm)均以直径为0.2~0.5mm的中根数量最多,在20-40cm沙层内细根(0.2mm)的根系总长度均最大,0-20cm沙层内中根根系总长度最大。在10-30cm沙层内,水平茎,垂直茎和主根长度、鲜重和干重均最大,40-50cm沙层内最小。以上结果表明,褐鳞苔草能很好地适应高寒风沙生境,可作为玛曲高寒沙漠化草地生态恢复的建群种,具有良好的推广应用前景。
[Abstract]:(Carex brunnescens) is a pioneer plant with strong sand fixation ability in desertification grassland in the source region of the Yellow River (Maqu), which plays an important role in maintaining the ecosystem stability of Maqu alpine grassland. In order to reveal the biological characteristics of sand fixation, the phenological characteristics, the growth process of the above-ground and underground organs and the morphological characteristics of the underground organs were observed in the field. The results showed that Cordyceps nigra returned to green early and had a long growth period with secondary flowering and fruiting characteristics. Leaf width per plant, leaf length per plant, number of leaves per plant, community density, community coverage and leaf density increased significantly from leaf developing stage to fruit ripening stage to yellow withered stage and then tended to stabilize. The leaf height per plant, the leaf area per plant and the leaf area of the community increased significantly and then decreased. The sand depth of the lower stem (horizontal stem and vertical stem) and root system is 0? 60 cm. In different sandy depths (0? 20, 20? 40 and 40-60cm), the number of middle roots with diameter of 0.2~0.5mm was the largest, the total root length of fine roots (0.2mm) in 20-40cm sand layer was the largest, and the total root length of middle root in 0-20cm sand layer was the largest. In 10-30cm sand layer, horizontal stem, vertical stem and main root length, fresh weight and dry weight were the largest, and 40-50cm sand layer was the smallest. The above results show that Cordyceps brownii can adapt to the alpine sandy habitat well and can be used as the ecological restoration group species in Maqu alpine desertification grassland, which has a good prospect of popularization and application.
【作者单位】：甘肃省林业科学研究院;
【基金】：国家自然科学基金“黄河源区(玛曲)沙化草地褐鳞苔草阻固沙机理研究”(31360087)
【分类号】：S812

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