摘要
【目的】对三江源区高寒草甸43种植物繁殖体的质量和形状进行比较,初步探讨研究区植物繁殖体的生存对策,为退化草地恢复治理和生物多样性保护提供理论依据。【方法】采集三江源区高寒草甸43种植物的繁殖体(13种为种子,30种为果实),称质量,用繁殖体三维(长、宽、高)的方差衡量繁殖体形状,并分析繁殖体质量、形状与植物物种生态特征的相关性。【结果】有15种植物繁殖体的单粒质量小于1 mg并接近圆球形(平均方差<0.09),其可能具有持久土壤种子库;多年生草本植物繁殖体的质量较1年或1/2年生草本植物大,形状较其扁且长;优良牧草与杂草繁殖体的质量和形状均有差异,杂草繁殖体单粒质量大,而牧草的繁殖体更扁、长;种子形状的平均方差较果实的小,但质量无明显差异;禾本科、菊科、莎草科植物多有扁平或细长繁殖体(平均方差>0.09),而质量无明显差异;繁殖体附属物在植物的传播和定居方面具有重要作用,其中75%的菊科植物具有冠毛,易于被风传播,89%的禾本科植物具芒,被风传播的概率小。【结论】植物物种的扩散和定居与繁殖体的质量和形状密切相关。
【Objective】 The paper studied the quality and shape of the diaspores of 43 plant species involving 13 seeds and 30 fruits from alpine meadow in the source region of three rivers.【Method】 The diaspores of 43 species were quantified,shapes of them were scaled with variance of three dimensions,and the relations between above indexes and ecological characteristics of diaspores were analyzed.【Result】 The results show that the quality of a single diaspore of 15 species is less than 1 mg,and its shape is close to sphericity because of variance less than 0.09 ,and it might have persistent soil seed bank,and is able to adapt to disturbance. The diaspores of perennials are heavier, flatter and longer than those of annuals. The diaspores of forb are heavier,and those of herbages are flatter and longer. Seeds are closer to sphericity in comparison with fruits. The diaspores of most of Compositae and Gramineae and Sedges species are flat and elongated because the variance is more than 0.09. The appendages of diaspores play an important role in dispersal and establishment. The diaspores of 75% Compositae species have pappuses,and might be dispersed by wind easily. And the diaspores of 89 % Gramineae species have awns which make them not likely to be dispersed. [Conclusion] The quality and shape of the diaspores of 43 species are different, which affect the survival strategy of species to a great extent.
出处
《西北农林科技大学学报（自然科学版）》
CSCD
北大核心
2009年第8期195-203,共9页
Journal of Northwest A&F University(Natural Science Edition)
基金
国家自然科学基金项目(30700563,30660120)
国家“973”计划项目专题(2009CB421102,2005CB422005-01)
中科院知识创新工程项目(KSCX2-YW-N-040-01)
中国科学院西部行动计划项目(KZCX2-XB2-06-02)
关键词
高寒草甸
繁殖体质量
繁殖体形状
生存对策
三江源区
alpine meadow
diaspore quality
diaspore shape
survival strategy
the source region of three river
