摘要
研究了红砂、泡泡刺、花棒、白刺和沙拐枣5种荒漠优势植物的幼苗出土和生长对沙埋的响应，判断了幼苗的生长特征能否预测植物的定植能力。进行了0、1、2、3、5cm和8cm等6个沙埋深度处理，每个处理5个重复。结果表明：每种植物的出苗率都随着沙埋深度的增加而降低，而且遵循着指数方程关系。红砂种子的最佳沙埋深度应为0-1cm，3cm已是出苗和存活的最大沙埋深度；泡泡刺、花棒和白刺种子的最佳深埋深度为0—3cm；沙拐枣在0—8cm各个深度都有出苗现象，且出苗率没有显著差异，但8cm深度的出苗率只有4％，最佳沙埋深度约为5cm。幼苗的生长高度受沙埋深度的影响显著，在同一时间，幼苗的最大生长高度并不在0cm表层，但红砂幼苗除外。泡泡刺、花棒和白刺在0—3cm的沙埋深度的幼苗生长高度大于5-8cm沙埋深度的生长高度，但沙拐枣幼苗在5cm深度的生长高度最大。5种荒漠植物幼苗的生物量受沙埋深度的影响不显著。在同一沙埋深度下，红砂的绝对高度生长率明显低于其余4种植物，沙拐枣的绝对高度生长率高于其余4种植物幼苗；5种植物的相对高度生长率对沙埋深度的响应并不敏感。绝对高度生长率与相对高度生长率并不能预示幼苗存活成功率。
The controlled experiment was conducted to test the seedling emergence and growth responses of five desert species to burial by sand, and to assess whether easily measured plant traits can be used to predict their probable success. Study species included 5 species of shrubs and sub-shrubs occurring frequently in arid region of northwest China. In the burial experiment, seedling emergence declined exponentially with sand burial depth. The optimal burial depth of Reaumuria soongorica is 0 -1cm, and the depth of 3cm is the maximum depth to emerge. There were no significant difference in the emergence of CaUigonum mongolicum at all sand burial depths, however, it is only 4% at the depth of 8cm. So the optimal burial depth is observed 5cm. The optimal burial depth of Nitraria sphaerocarpa, Hedysarum scoparium and Nitraria tangutorum was also in the range of a shallow burial depth, and the approximate depths of the three desert species were 0 - 3cm. Seedling height was significantly affected by the sand burial depth. At the same period, the maximum height of most species were not in the surface, except Reaumuria soongorica, and the growth height of 0-3cm was bigger than those in 5 - 8cm for Nitraria sphaerocarpa, Hedysarum scoparium and Nitraria tangutorum, and the maximum height of Calligonum mongolicum was at the depth of 5cm. However, the biomass of the five desert species had no significant correlations with the sand burial depth. At the same sand burial depth, largerseeded species like Calligonum mongolicum had the larger absolute height growth rate, which may help to explain their prevalence in the desert. However,seedling relative height growth rate was not significantly affected by plant species and sand burial depth.Absolute and relative height growth rate alone do not necessarily predict seedling survival success. In a restoration context, desirable species that are vulnerable during emergence and establishment can be targeted, and plant species, seedling growth rate and sand burial depth are determinants of
出处
《生态学报》
CAS
CSCD
北大核心
2006年第6期1802-1808,共7页
Acta Ecologica Sinica
基金
国家自然科学基金资助项目(40571026)
中国科学院野外台站基金资助项目(2005410)~~
关键词
沙埋深度
出苗
高度生长率
荒漠植物
sand burial depth
seedling emergence
seedling height growth rate
desert species
