两种旱生灌木种子萌发与幼苗复活对模拟干湿处理的响应  

Response of germination and seedling survival of two shrubs to simulated dry-wet treatments

作　　者：曲文杰 赵文智[1] 王磊 屈建军[1] 杨新国 QU Wen-jie;ZHAO Wen-zhi;WANG Lei;QU Jian-jun;YANG Xin-guo(Northwest Institute of Eco-Environment and Resource,Chinese Academy of Sciences,Lanzhou 730000,China;College of Ecology and Environmental Science,Ningxia University,Yinchuan 750021,China;Breeding Base for State Key Laboratory of Land Degradation and Ecological Restoration in Northwest China,Ningxia University,Yinchuan 750021,China;University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]中国科学院西北生态环境资源研究院,甘肃兰州730000 [2]宁夏大学生态环境学院,宁夏银川750021 [3]宁夏大学西北退化生态系统恢复与重建教育部重点实验室,宁夏银川750021 [4]中国科学院大学,北京100049

出　　处：《草业学报》2023年第11期179-187,共9页Acta Prataculturae Sinica

基　　金：宁夏自然科学基金(2021AAC03083)资助。

摘　　要：降水稀少、不可预测及其所带来的干湿变化深刻影响着旱区植物种子萌发和幼苗定居过程。柠条和花棒是腾格里沙漠常见的并广泛用于沙漠化治理的两种典型旱生灌木,本研究采用室内模拟干湿处理的方法对比分析了两者种子萌发率和幼苗复活的响应。结果表明,与CK相比,湿润-干旱处理显著提高了柠条种子的萌发率(P<0.05),而对花棒种子的萌发率无显著影响,同时显著提高了柠条种子第1天的萌发率(27.99%,P<0.05)和花棒种子第2天的萌发率(46.88%,P<0.05)。干旱复水处理的花棒早期幼苗平均复活率高于柠条。根长为0~0.2cm的柠条和花棒早期幼苗遭受45 d干旱后都可复活。根长为0.5~1.0 cm的柠条和花棒早期幼苗的干旱不归点分别是21和45 d;根长为1.0~1.5 cm时不归点分别是7和14 d。总体而言,干湿处理有利于种子萌发,但是随幼苗生长,对干旱的耐受程度也随之降低;相对而言,花棒对持续干旱的适应性要强于柠条。在长期气候变化背景下,建议研究区人工固沙植被可以更多选择花棒一类的灌木,从而提高固沙植被的相对稳定性。Caragana korshinskii and Corethrodendron scoparium are two typical xeriscape shrubs widely used in ecological construction in arid and semi-arid areas.Differences in precipitation intensity and interval profoundly affect germination and seedling survival,and the two processes are key factors limiting vegetation natural regeneration.In this study,the effects of dry-wet treatments on C.korshinskii and C.scoparium germination and seedling survival were examined using standard procedures.It was found that,compared to CK,only C.korshinskii germination was significantly affected by dry-wet treatments.The best treatments increased germination of C.korshinskii at day 1 by 27.99%(P<0.05),and of C.scoparium at day 2 by 46.88%(P<0.05).Compared to C.korshinskii,the revival rate of young C.scoparium seedlings after rehydration was higher.Yong seedlings of C.korshinskii and C.scoparium with root length of 0-0.2 cm desiccated up to 45 days revived after rehydration.The points of no return of young C.korshinskii and C.scoparium seedlings of 0.5-1.0 cm root length were 21 and 45 days,respectively.At a root length of 1.0-1.5 cm,the points of no return were 7 and 14 days,respectively.In summary,the hydration/dehydration treatments were beneficial to germination,but the tolerance to desiccation decreased with the growth of seedlings.In general,the adaptation of C.scoparium to desiccation was stronger than that of C.korshinskii.We suggest that more use of shrubs such as C.scoparium can be made to fix sand as part of response to climate change in the study area,so as to improve the relative stability of artificial vegetation.

关 键 词：腾格里沙漠 种子萌发 幼苗复活 干湿处理 柠条 花棒 

分 类 号：S793.9[农业科学—林木遗传育种]