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题名	冷荒漠降水增加对囊果苔草生活史及繁殖对策的影响
作者	李雪峰
答辩日期	2017-05-01
文献子类	硕士
授予单位	中国科学院大学
授予地点	新疆乌鲁木齐
导师	张道远
关键词	囊果苔草 降水增加 繁殖对策 克隆植物 Carex physodes Increasing precipitation Reproductive strategy Clonal plant
学位专业	工程硕士
英文摘要	Ephemeral plant is a unique existence in cold desert around the world and playsimportant role in maintaining ecological stability in Gurbantunggut desert of Xinjiang,Northwest China. In order to understand the reproductive strategy adjustment ofephemeral plant under continuously precipitation increase in cold desert, we chooseCarex physodes, an endemic ephemeroid rhizomatous clonal plant from Cyperaceaefamily, as study object. The characteristics of seed germination and seedlingestablishment were studied both in indoor control and field survey under snowenhancement in winter and water enhancement in spring-summer seasons. The clonalreproductive strategies and sexual reproduction allocation were also monitored duringthe treatments. The main results and conclusions are as follows:(1) Under different snowfall conditions, the seed vigor and germination rate of C.physodes were different. The seed vigor and germination rate were higher under snowenhancement, indicating that increased snowfall is beneficial to the vigor of seeds,and also subsequent seed germination.(2) Increased rainfall affect the vegetative growth of C. physodes compared withthe natural state. The crown length and width, and the leaf number decreased underwater enhancement, while the plant height increased, with up to 14.41% increaseunder 50% water enhancement. The underground biomass and diameter of rhizomaticroot increased its the waterfall enhancement. This showed that C. physodes maybereduce surface face by reducing leaf number and crown length and width, andincrease the biomass input in underground parts, to adapt to water enhancement inarid desert environment.(3) Compared with the natural waterfall amount, Carex physodes reproductivestrains and vegetative strains numbers increased, and the effect was significant forreproductive strains. Reproductive strains increased by 176% under 30% waterenhancement, and by 281% under 50% water enhancement, and the ratio of reproductive and vegetative stain number was also raised. Thus, the results indicatethat the increase of spring and summer precipitation promotes C. physodesreproductive and vegetative strains growth, which benefit for the populationdevelopment of the species in desert.(4) Compared with the natural state, water enhancement made Carex physodesfruit's length increase, while fruit width decrease. And made seed width increase, andseed length decrease, with 6.52% decrease under 30% water enhancement and 2.55%decrease under 50% water enhancement. The thousand seed weight decreased and thethousand fruit weight increased. These results showed that the increase of spring andsummer precipitation may affect the reproductive organ plasticity of C. physodes, andthe following seed dispersal and inhibition in the desert.
语种	中文
学科主题	生物工程
内容类型	学位论文
源URL	[http://ir.xjlas.org/handle/365004/14884]
专题	新疆生态与地理研究所_研究系统_荒漠环境研究室
作者单位	中国科学院新疆生态与地理研究所
推荐引用方式 GB/T 7714	李雪峰. 冷荒漠降水增加对囊果苔草生活史及繁殖对策的影响[D]. 新疆乌鲁木齐. 中国科学院大学. 2017.

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