水生态学杂志2016，Vol.37Issue(3)：34-41,8.DOI:10.15928/j.1674-3075.2016.03.005
天鹅洲湿地退化区土壤种子库与地面植被关系初探
Relationship Between Soil Seed Bank and Above-ground Vegetation in the Degraded Wetland Region of Shishou Swan Island Elk Nature Reserve,Hubei Province
摘要
Abstract
The soil seed bank accumulates from seeds produced by above-ground vegetation and,to a certain ex-tent,reflects the condition of past vegetation and can be used to predict vegetation composition and succession. Therefore,the study of soil seed bank composition and characteristics is important for evaluating seed reserves and the self-restoring potential of a degraded wetland ecosystem.In this study,the relationship and differences between seed bank and above-ground vegetation were investigated in the degraded wetland zone of Shishou Swan Island Elk Nature Reserve using a seedling germination experiment and field survey from January to July,2015.The reserve is located on the north shore of lower Jingjiang River,part of a former channel of the Yangtze River.The nature re-serve wetland area has been declining sharply since construction of Three Gorges Dam due to decreased water circu-lation,large scale expansion of Populus euramericana and other human activities.Soil samples for the seedling ger-mination experiment were collected at 30 sites in January and stored in the laboratory.The seedling germination ex-periment was carried out from March 25 to July 25 and field investigation of vegetation at soil sampling sites was carried out on July 22 -23.Plant species and number,height and cover were recorded for the seed germination ex-periment and field investigation.In the germination experiment,Gramineae was the first to germinate,followed by Xanthium sibiricum and Humulus scandens.The growth rate of Humulus scandens (0.4 -1.2 cm /d)was faster than Xanthium sibiricum (0.2 -1.0 cm /d)and Gramineae (0.1 -0.4 cm /d).The seed bank in the degraded wetland zone contained 18 families,33 genera and 34 species with an average seed density of 6 153 seeds/m2 and domina-ted by 23 annual herbs.The above-ground vegetation consisted of 21 families,32 genera and 32 species,domina-ted by 21 perennials herbs.The soil seed bank and above-ground vegetation displayed a high similarity in species composition,sharing 20 species,a Jaccard similarity coefficient of 0.435 and a Srenson similarity coefficient of 0.606.However,species diversity and evenness were higher in the above-ground vegetation than in the seed bank:Shannon-Wiener diversity index 2.488 >1.886,Simpson diversity index 0.889 >0.672 and Pielou uniformity in-dex 0.783 >0.539.Dominant species in the seed bank were Setaria viridis and Poa annua,while dominant species in the above-ground vegetation were Cayratia japonica,Paederia scandens and Sambucus javanica.Our results re-vealed the relationship between the seed bank and above-ground vegetation in the degraded wetland zone of Swan Island and will provide theoretical and practical knowledge to support restoration of degraded wetlands.关键词
种子库/地面植被/湿地退化/优势种/天鹅洲Key words
seed bank/above-ground vegetation/wetland degradation/dominant species/Swan Island分类
农业科技引用本文复制引用
力志,操瑜,付文龙,王伟,李鹏飞,温华军,李伟..天鹅洲湿地退化区土壤种子库与地面植被关系初探[J].水生态学杂志,2016,37(3):34-41,8.基金项目
国家科技支撑计划（2012BAC06B04）；湖北省自然科学基金（2014CFA137）；三峡后续工作科研项目“三峡水库小江生态恢复关键技术研究与示范”（2013HXKY2-3）。 （）
