首页关于本刊影响因子及获奖投稿须知订阅及广告专辑与专题学术会议绿色发表通道优秀论文 
说明:
此论文已被《生态学报》录用,现已优先出版,可查看文章PDF版本!
李周,赵雅洁,宋海燕,张静,陶建平,刘锦春.不同水分处理下喀斯特土层厚度异质性对两种草本叶片解剖结构和光合特性的影响.生态学报,2018,(2).http://dx.doi.org/10.5846/stxb201701180148  
不同水分处理下喀斯特土层厚度异质性对两种草本叶片解剖结构和光合特性的影响
Effects of karst soil thickness heterogeneity on the leaf anatomical structure and photosynthetic traits of two grasses under different water treatments
投稿时间:2017-01-18  修订日期:2017-08-28
DOI: 10.5846/stxb201701180148
关键词喀斯特  土层空间异质性  叶脉  气孔  光合生理
Key Wordskarst, spatial  heterogeneity of  soil, vein, stomata, photosynthetic  physiology
基金项目国家自然科学基金资助项目(31500399);重庆市自然科学基金资助项目(cstc2014jcyjA80016);教育部第49批留学回国人员科研启动基金资助项目*通讯作者 Corresponding author. E-mail:jinchun@swu.edu.cn
作者单位E-mail
李周 三峡库区生态环境教育部重点实验室 lizhou1017@qq.com 
赵雅洁 三峡库区生态环境教育部重点实验室  
宋海燕 三峡库区生态环境教育部重点实验室  
张静 三峡库区生态环境教育部重点实验室  
陶建平 三峡库区生态环境教育部重点实验室  
刘锦春 三峡库区生态环境教育部重点实验室 jinchun@swu.edu.cn 
摘要点击次数 173
全文下载次数 29
摘要:
为了探究不同水分处理下草本植物对喀斯特土层厚度变化的叶片形态建成和光合生理响应,以黑麦草(Lolium perenne L.)和苇状羊茅(Festuca arundinacea Schreb.)为研究对象,通过盆栽水分受控试验,研究了3种水分处理[正常供水(Wck),减水1组(D1)和减水2组(D2)]下3种土层厚度[浅土组(SS)、对照组(SCK)和深土组(SD)]对两种草本叶片解剖结构和光合特性的影响。结果表明:(1)正常供水下(Wck),黑麦草和苇状羊茅在浅土组(SS)的气孔密度和气孔限制值(Ls)均显著高于对照组(SCK),净光合速率(Pn)、胞间CO2浓度(Ci)和蒸腾速率(Tr)降低;在深土组(SD),两种植物的气孔密度都有所下降,黑麦草的叶脉密度、Pn和Tr均低于对照组,而苇状羊茅的叶脉密度和Pn表现出增加;(2)D1水分条件下,黑麦草在浅土组的气孔密度较对照组增加,叶脉密度、Pn和Tr均降低,而苇状羊茅的气孔密度有所降低,叶脉密度、Pn和Tr未受到显著影响;在深土组中,黑麦草的气孔密度不变,叶脉密度增加,而Pn和Tr均降低;苇状羊茅的气孔密度降低,但叶脉密度、Pn和Tr均升高;(3)D2水分条件下,两种植物在浅土组的叶脉密度较对照组均增加,气孔密度、Pn和Tr均受到抑制;在深土组,黑麦草的远轴面气孔密度较对照组下降,两种植物的其他指标未受到明显影响。可见,在不同水分条件下,植物的叶片解剖结构和光合特性对不同土层厚度的响应不一,且不同物种间也有差异。总体上随着水分减少,土层厚度降低对植物的光合抑制作用增强,而厚度增加对深根植物的光合促进作用和对浅根植物的光合抑制作用先增强后减弱。植物气孔和叶脉性状特征随水分条件的变化在一定程度上与叶面积和叶片宽度的变化有关。
Abstract:
Congenitally slow soil development rates and acquired rocky desertification ensure a serious shortage of soil resources in karst areas. Coupled with the steep terrain, soil distribution is uneven with a high degree of heterogeneity in space in karst regions. In the karst depression, basin, and valley areas, soil thickness and soil distribution are continuous; however, in the hill slope area, soil is usually “rock soil” or is missing. Uneven distribution of karst soil also leads to obvious spatial heterogeneity of moisture. Global precipitation changes might aggravate heterogeneity of soil moisture in soils of different thicknesses. Plant morphogenesis is very sensitive to soil moisture, including the leaf veins that control water transport and utilization and the stomata that adjust the balance of water and CO2. Simultaneously, photosynthesis that utilizes water and CO2 as raw materials is also directly affected by soil moisture. Thus, exploring the responses of the leaf anatomical structure and photosynthetic traits of plants to water availability and soil heterogeneity in karst regions is necessary to understand how precipitation changes might affect plant growth and physiology in soils of different thicknesses. Herbaceous plants, especially grasses in karst regions, are most often affected by soil heterogeneity and water availability because they mainly utilize water and nutrients from the surface soil via their fibrous root system. Two graminaceous perennial grasses, Lolium perenne L. and Festuca arundinacea Schreb. were chosen for the present study. These two species are often chosen as pioneer plants for ecological restoration and reconstruction in karst regions because of their attributes of fast growth, strong adaptive ability, and high yield, which effectively promote economic development and assist to alleviate rural poverty in harsh karst regions. In the present study, three water treatments (WCK: 40 mL/d, D1: 20 mL/d, and D2: 12 mL/d) were combined with three levels of soil thickness [shallow soil (SS: 5 cm), control (SCK: 15 cm), and deep soil (SD: 30 cm)] in a factorial randomized design and measurements were obtained of leaf vein and stomata traits and several photosynthetic parameters. The following results were obtained: (1) Under normal water supply conditions (WCK), the stomatal density and stomatal limitation (Ls) of L. perenne and F. arundinacea were significantly higher in the SS group than in the SCK group, and the two species net photosynthetic rate (Pn), intercellular CO2 concentration (Ci), and transpiration rate (Tr) decreased. In the SD group, the stomatal density of both species decreased, the leaf density, Pn, and Tr of L. perenne were lower than those in SCK, and the leaf density and Pn of F. arundinacea increased. (2) Under D1 water treatment, the stomatal density of L. perenne in SS was higher than that in SCK, and leaf vein, Pn, and Tr decreased; however, the stomatal density of F. arundinacea in SS showed some decrease, and the leaf vein, Pn, and Tr of F. arundinacea were not significantly affected. In the SD group, the stomatal density of L. perenne did not change, the leaf vein increased, and the Pn and Tr were both decreased, while the stomatal density of F. arundinacea decreased and the leaf vein, Pn, and Tr increased. (3) Under D2 water treatment, the leaf veins of the two species increased in the SS group as compared to that in SCK, and their stomatal density, Pn, and Tr were suppressed. In the SD group, compared to SCK, the stomatal density of L. perenne decreased and the other parameters in both plants were not significantly affected. The results of the present study indicate that under different water conditions, the leaf anatomical structure and photosynthetic characteristics of the two plant species studied were different in response to the different thickness soils, with differences recorded between the different species. Overall, as the water content decreased, the inhibition that plant photosynthesis suffered was enhanced by a decrease of soil thickness, and the promotion effect that the deep root plant received and the inhibition that the shallow root plant suffered were first strengthened and then weakened by an increase in soil thickness. The variation of vein density and stomatal density with water content is related somewhat to the change of leaf area and leaf width.
HTML 查看全文   查看/发表评论  下载PDF阅读器

您是本站第 64918717 位访问者

Copyright © 2005-2019   京ICP备06018880号
地址:北京海淀区双清路18号
  邮编:100085    电话:010-62941099
  E-mail : shengtaixuebao@rcees.ac.cn
本系统由北京勤云科技发展有限公司提供技术支持