李德晖^1,,
介冬梅^1,2,3,,,
高桂在¹,
李楠楠¹,
刘利丹⁴,
冷程程¹,
刘洪妍⁵,
蒙萌¹
1. 东北师范大学地理科学学院, 吉林 长春 130024
2. 国家环境保护湿地生态与植被恢复重点实验室, 吉林 长春 130024
3. 植被生态科学教育部重点实验室, 吉林 长春 130024
4. 湖南师范大学资源与环境科学学院, 湖南 长沙 410001
5. 安阳师范学院资源环境与旅游学院, 河南 安阳 455000

基金项目: 国家自然科学基金项目（批准号：41771214和41471164）和国家自然科学基金青年项目（批准号：41602194）共同资助


详细信息

作者简介: 李德晖, 女, 28岁, 博士研究生, 自然地理学专业, E-mail:lidh357@nenu.edu.cn

通讯作者: 介冬梅, E-mail:jiedongmei@nenu.edu.cn

中图分类号: Q948.15⁺5;Q949.71⁺4.2

收稿日期:2018-03-06
修回日期:2018-05-03
刊出日期:2018-07-30

Characteristics of phytolith assemblages of topsoil in typical communities of Songnen Grassland

Li Dehui^1,,
Jie Dongmei^1,2,3,,,
Gao Guizai¹,
Li Nannan¹,
Liu Lidan⁴,
Leng Chengcheng¹,
Liu Hongyan⁵,
Meng Meng¹
1. School of Geographical Sciences, Northeast Normal University, Changchun 130024, Jilin
2. State Environmental Protection Key Laboratory for Wetland Conservation and Vegetation Restoration, Changchun 130024, Jilin
3. Key Laboratory of Vegetation Ecology, Ministry of Education, Changchun 130024, Jilin
4. College of Resource and Environment Science, Hunan Normal University, Changsha 410001, Hunan
5. School of Resources Environment & Tourism, Anyang Normal University, Anyang 455000, Henan


More Information

Corresponding author: Jie Dongmei,E-mail:jiedongmei@nenu.edu.cn

MSC: Q948.15⁺5;Q949.71⁺4.2

--> Received Date: 06 March 2018
Revised Date: 03 May 2018
Publish Date: 30 July 2018


摘要
摘要:植硅体在草原古植被重建中具有重要意义和巨大潜力。对松嫩草原的57个表土样品植硅体从形态类型、组合两方面进行分析，通过DCA（Detrended Correspondence Analysis）排序确定各形态类型的生态意义，判别分析实现了较精细水平上的群落类型判别。研究结果表明：松嫩草原典型群落对应表土植硅体组合多以平顶帽型为优势类型；弱齿型和多齿型指示相对湿润的环境，针茅哑铃型能够指示针茅群落，简单哑铃型能够指示较干旱的环境且对应于羊草、冰草等群落，较高含量的硅质突起指示苔草属群落。判别分析结果将57个表土样品划分为4组：灌丛群落、非禾草草本植物群落、C₃禾草群落以及C₄禾草群落，各自的正确率分别为85.7%、89.5%、79.2%和85.7%，总正确率为84.2%。本项研究对理解松嫩草原植硅体的环境意义，为恢复区域古植被提供了现代过程依据，以期在日后通过沉积物植硅体分析得到稍高精度的古植被重建结果。
关键词: 植硅体/
松嫩草原/
草甸草原/
判别分析/
古植被

Abstract:This study collected 57 topsoil samples corresponding to 24 typical community types in Songnen Grassland, and investigated phytolith morphotypes and assemblages in them. Songnen Grassland is located in the western of Jilin Province and Heilongjiang Province, and the eastern of Inner Mongolia, with a total area of 1.7×10⁵ km². The mean temperature in July is 22~25℃, while -22~-16℃ in January. Precipitation decreased from east Songnen Grassland to west, and the mean annual precipitation is 300~350 mm. According to community types, 57 samples were classified into four groups in three procedures:(1) If a shrub layer was occurred in a community, it was classified as shrub community; and a community without shrub layer was classified as non-shrub community; (2) Among non-shrub communities, if Poaceae plant was dominant in a community, it could name as grass community; and the others could classified as forb community; (3) Among grass communities, C₃ grass community was defined when C₃ grass was the dominant species, and C₄ grass community was defined when C₄ grass was the dominant species.
Phytoliths were extracted by wet oxidation method and heavy liquid flotation. Canada balsam were used to prepare slides. At least 300 grain phytoliths were observed and identified in each slide(sample). As to data analysis method, diatoms and sponge spicules were excluded when calculating phytolith assemblages, because their origination were different with phytoliths. However, since these Bio-Si also contained environmental significance, we calculated their percentages respectively by regarding the sum of phytoliths counts, diatoms counts, and sponge spicules counts as denominator.
GeoMapApp was applied to draw the sampling sites graph, and Photoshop CS 5 was used to make the plate of phytoliths. Phytolith assemblages diagram was drawn by Tilia. Detrended Correspondence Analysis(DCA) was completed in Canoco for Windows 4.5, and Discriminant Analysis(DA) was completed in SPSS 18.0.
A total of 30 phytolith morphotypes were identified and grouped into seven categories according anatomical items:Ⅰ. Short cell phytolith(saddle, rondel flat, rondel ridge, rondel echinate, trapeziform, trapeziform with two-half lobate, trapeziform with three lobate, trapeziform sinuate, trapeziform polylobate, bilobate type-A, bilobate type-B, bilobate type-C, bilobate type-D, cross-shaped phytolith, cylindrical polylobate, Stipa-bilobate, simple bilobate), Ⅱ. Long cell phytolith(elongate smooth, elongate echinate, elongate process, elongate cave), Ⅲ. Hair cell phytolith(large hair phytolith, little hair phytolith, lanceolate), Ⅳ. Bulliform cell phytolith(cuneiform bulliform cell phytolith, parallelepipedal bulliform cell phytolith), Ⅴ. Stoma guard cell and subsidiary cell phytolith(silicified stoma guard cell), Ⅵ. Epidermal cell phytolith(tabular stellate), Ⅶ. Phytolith that anatomic unknown(papillate, blocky). Besides, other Bio-Si like diatoms and sponge spicules, which containing environmental significance were also identified and counted.
Rondel flat was the dominant type of most topsoil phytolith assemblages, such as Stipa capillata community (51.29%), and rondel flat in C₄ grass communities were less than C₃ grass communities(ranged from 20.30%to 28.66%). The dominant phytolith types in forb communities were rarely to be flat rondel, for example, elongate smooth were abundant in Cyperaceae community, and saddle(32.83%) were dominant in Artemisia anethifolia community.
DCA was applied to find the ecological meaning of each phytolith morphotypes in Songnen Grassland. Trapeziform sinuate and trapeziform polylobate may indicate wetter conditions in Songnen Grassland, and Stipa-bilobate could indicate communities that contain Stipa plants. Simple bilobate possibly implied drier conditions, and occurred in Leymus chinensis community and wheatgrass which may due to succession of community. High percentage of papillate, especially conjoint with abundant diatoms and sponge spicules, potentially indicated Cyperaceae community.
57 phytolith assemblages of topsoil in Songnen Grassland were employed in DA to find the differences between different community groups. Shrub community, forb community, C₃ grass community and C₄ grass community were discriminated correctly with accuracies of 85.7%, 89.5%, 79.2%and 85.7%, respectively. The finer discriminant result with a high total accuracy(84.2%) probably indicated that DA is applicative in discrimination of community types, and could do some help in future palaeovegetation reconstruction in Songnen Grassland.
Key words:phytolith/
Songnen Grassland/
meadow steppe/
discriminant analysis/
palaeovegetation



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