文献类型：期刊文献

中文题名：模拟增雨对荒漠植物幼苗生长和根系形态的影响

英文题名：Effects of simulated precipitation addition on growth and root morphological characteristics of desert plant seedling

作者：李新乐[1,2,3] 张景波[1] 董雪[1,3] 辛智鸣[1,3] 段瑞兵[1,3] 罗凤敏[1,3] 李永华[2]

第一作者：李新乐

机构：[1]中国林业科学研究院沙漠林业实验中心,磴口015200;[2]中国林业科学研究院,荒漠化研究所,北京100091;[3]内蒙古磴口荒漠生态系统国家定位观测研究站,磴口015200

年份：2020

卷号：40

期号：10

起止页码：3452-3461

中文期刊名：生态学报

外文期刊名：Acta Ecologica Sinica

收录：CSTPCD;;Scopus;北大核心:【北大核心2017】；CSCD:【CSCD2019_2020】；

基金：中国林业科学研究院基本科研业务费专项资助(CAFYBB2020MB007);内蒙古磴口荒漠生态系统国家定位观测研究站运行补助(201913214)。

语种：中文

中文关键词：荒漠植物幼苗;模拟增雨;生物量;根系形态;根冠比

外文关键词：desert plant seedlings;simulated precipitation addition;biomass;root morphological;root-shoot ratio

分类号：S51

摘要：降雨是荒漠生态系统过程和功能的最重要限制因子,荒漠植物幼苗对生长季降雨的变化极端敏感。为探讨荒漠植物对未来降雨格局变化的响应,选取乌兰布和沙漠两种典型荒漠植物幼苗(白刺和油蒿)为研究对象,根据生长季内(6-9月)每次降雨量,进行不同梯度的人工模拟增雨试验(CK:自然降雨、A:增雨25%、B:增雨50%、C:增雨75%、D:增雨100%),研究两种植物幼苗生长和根系形态特征对降雨量变化的响应。结果表明:(1)不同增雨处理对白刺和油蒿幼苗的地上部生长有显著影响(P<0.05),增雨处理的白刺和油蒿幼苗的株高、平均冠幅和基径显著高于CK,并随着增雨量的增大而增大(白刺基径除外);(2)增雨处理之间、白刺和油蒿之间在总根长、总表面积、平均直径、总体积、根尖数和分叉数均有显著差异(P<0.05)。对白刺幼苗而言,B处理和C处理的根系参数均显著大于CK、A和D处理,且B和C处理之间没有显著差异(平均直径除外);对油蒿幼苗而言,随着增雨量的增加,油蒿总根长、总表面积、总体积、根尖数和分叉数呈现逐渐增加的趋势,而平均直径呈现先增加后降低的趋势,且在B处理下达到最大值。(3)增雨处理显著降低了白刺幼苗的根冠比,而对油蒿幼苗的根冠比没有显著影响,并且白刺幼苗根冠比显著大于油蒿幼苗。(4)白刺和油蒿幼苗的根系主要分布在0-0.5 mm和0.5-1 mm内,<2 mm的细根比例分别在B和D处理下达到最大值。这表明白刺和油蒿幼苗能够通过调整地上部生长和根系形态来适应降雨的变化。
Precipitation is the most important limiting factor for processes and functions of desert ecosystems and desert plant seedlings are extremely sensitive to precipitation changes during the growing season.In order to explore the response of desert plant seedlings to future precipitation pattern changes,two typical desert plant seedlings(Nitraria tangutorum and Artemisia ordosica)in Ulan Buh desert were selected as research objects.The artificial simulated precipitation addition experiment was conducted with five different gradients(CK:natural precipitation,A:+25%precipitation,B:+50%precipitation,C:+75%precipitation,D:+100%precipitation)based on the precipitation of growing season from June to September to study the growth of two plant seedlings and the response of root morphological characteristics to precipitation changes.The results showed that 1)different precipitation treatments had significant effects on the shoot growth of Nitraria tangutorum and Artemisia ordosica seedlings(P<0.05).The height,average crown,and base diameter of Nitraria tangutorum and Artemisia ordosica seedlings were significantly higher than the CK and increased with the amount of precipitation(except for the base diameter of Nitraria tangutorum).2)There were significant differences in total root length,total surface area,average diameter,total volume,number of root tips and number of branches between precipitation treatments(P<0.05).For the Nitraria tangutorum seedlings,the root parameters of B and C treatments were significantly greater than those of CK,A and D treatments,and there was no significant difference between B and C treatments(except for the average diameter);for the Artemisia ordosica seedlings,the total root length,total surface area,total volume,number of root tips and number of branches increased gradually with the increase of precipitation,while the average diameter increased first and then decreased,and reached the maximum under B treatment.3)Precipitation addition treatment significantly reduced the root-shoot ratio of Nitraria tangutorum seedlings,but had no effect on the seedlings of Artemisia ordosica,and the root-shoot ratio of Nitraria tangutorum seedlings was significant greater than the seedlings of Artemisia ordosica.4)The roots diameter of two seedlings were mainly distributed in 0—0.5mm and 0.5—1mm,and the ratio of fine root(<2mm)reached the maximum value under B and D treatment,respectively.It suggested that Nitraria tangutorum and Artemisia ordosica seedlings could adjust shoot growth and root morphology to adapt precipitation changes.