摘要
以古尔班通古特沙漠10种不同生活型植物种子为对象,研究3种不同积雪覆盖变化(自然降雪、加倍降雪和去除降雪)对荒漠植物种子萌发的影响。根据种子室内萌发结果,将种子可分为高萌速萌、高萌缓萌、低萌速萌和低萌缓型4种萌发类型。总体而言,加雪处理对荒漠植物的种子萌发率具有正效应或无效应,而去雪处理则具有负效应或者无效应。将野外不萌发的种子于室内重新培养,结果显示,积雪变化对总萌发率(野外萌发+室内萌发)具正、负或无3种效应。研究表明,在荒漠生态系统中,植物种子在萌发类型上具有多样性,这种多样性与植物的生存环境密切相关。积雪覆盖可以通过影响植物种子野外萌发率或总萌发率来影响植物生存。不同植物种子萌发对积雪覆盖变化的响应策略大都与生活型无关。这种多样化的种子萌发响应模式,有利于荒漠植物群落在环境剧烈变化中保持结构和功能的稳定,是对环境长期适应的结果。
In this study, ten desert species including three life-forms from Gurbantunggut Desert were selected to study the effects of different snow covers on seed germination. Three kinds of snow cover treatments were settled, i.e. snow doubling, natural snow and snow removal. Based on the results from indoor experiments, the seed germination types could be divided into four types, including high germination percentage with rapid germination rate, high germination percentage with slow germination rate, low germination percentage with rapid germination rate, and low germination percentage with slow germination rate. The treatments of double snow cover had positive or neutral effects on seed germination, while snow removal showed negative or neutral effects. After indoor re-germination of those seeds which did not germinate in field sites, we found that snow cover had positive, neutral or negative effects on total germination percentages. Our results indicated that the germination of seeds from desert ecosystems had diverse germination types, which were related to the plant growth environment. The snow cover affected plant presence by changing the field or total germination percentages. Different species in the desert ecosystems evolved into different response strategies under changing environments （i.e. snow cover） , most of which were not life-form depended. The diversity of seed germination responses resulted from long-term evolution, being beneficial for the plant community to keep its structure and function stability.
出处
《生态学杂志》
CAS
CSCD
北大核心
2016年第9期2348-2354,共7页
Chinese Journal of Ecology
基金
国家重点基础研究计划项目(2014CB954202)
国家自然科学基金-新疆联合基金项目(U1503101)资助
