| 引用本文: | 陈明珠,靳朝,雷光春,阳俭,雷霆.洞庭湖洲滩土壤种子库对土壤水分变化的响应.湖泊科学,2020,32(3):745-753. DOI:10.18307/2020.0314 |
| CHEN Mingzhu,JIN Zhao,LEI Guangchun,YANG Jian,LEI Ting.The response of soil seed bank diversity to soil moisture change in Lake Dongting. J. Lake Sci.2020,32(3):745-753. DOI:10.18307/2020.0314 |
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| 摘要: |
| 由于三峡大坝及上游水库群的运行，长江中下游水域水文节律随之发生了改变，导致洞庭湖枯水期提前，进而影响洞庭湖洲滩植被及其土壤种子库的分布格局.本研究在洞庭湖4个自然保护区内选取共11个典型洲滩湿地，沿由水到陆方向根据植被类型将洲滩分为泥沙洲滩、泥沙-湖草洲滩过渡带、湖草洲滩、湖草-南荻洲滩过渡带、南荻洲滩5种洲滩类型.通过样带-样方法调查和采样，并结合湿润和水淹两种条件下的土壤种子库萌发实验，分析了土壤水分变化对洲滩种子库萌发特征的影响及土壤种子库与地表植被的关系.结果显示：①土壤含水量沿水到陆方向由泥沙洲滩向南荻洲滩递减；②不同类型洲滩土壤种子库密度没有显著差异；③温室萌发实验中，水淹条件下土壤种子库物种丰富度和种子库密度显著降低，东洞庭湖自然保护区土壤种子库物种丰富度和种子库密度较高；④地表植被物种丰富度高于土壤种子库，泥沙洲滩土壤种子库与地表植被物种组成的Jaccard相似性指数最低.此外，虉草（Phalaris arundinacea）、芦苇（Phragmites communis）、南荻（Miscanthus sacchariflorus）等只在地表植被中存在，而陌上菜（Lindernia procumbens）、通泉草（Mazus japonicus）等只在种子库中存在.结果表明，在进行湿地植被恢复时，不能仅依靠种子库移植技术，还要考虑湖区季节性的水位变化以及个别物种的特异性，配合有针对性的水文调控机制及相关的人工措施恢复其原有植被. |
| 关键词: 土壤种子库 物种多样性 地表植被 洞庭湖 洲滩湿地 土壤含水量 |
| DOI：10.18307/2020.0314 |
| 分类号: |
| 基金项目:国家重点研发计划项目（2018YFC0507200）资助. |
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| The response of soil seed bank diversity to soil moisture change in Lake Dongting |
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CHEN Mingzhu1, JIN Zhao2, LEI Guangchun1, YANG Jian3, LEI Ting1
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1.School of Ecology and Nature Conservation, Beijing Forestry University, Beijing 100083, P. R. China;2.Henan Entry-Exit Inspection and Quarantine Bureau, Zhengzhou 450003, P. R. China;3.West Dongting Lake National Nature Reserve, Hunan Province, Yueyang 415923, P. R. China
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| Abstract: |
| Due to the operation of the Three Gorges Dam and upstream reservoir groups, the hydrological rhythm of the middle and lower reaches of the Yangtze River has changed subsequently, which resulted in habitat changes in Lake Dongting. However, these habitat changes not only affect the distribution of wetland vegetation but also influence the soil seed bank in Lake Dongting. To explore the influence of soil moisture variation on wetland soil seed bank germination and the relationship between soil seed bank and ground vegetation, 11 typical sites were set in field investigation, which were classified into 5 kinds of floodplains (silt floodplain, silt and grass transition zone, grass floodplain, grass and reed transition zone, reed floodplain). In addition, soil seed bank germination experiment was carried out under two types of treatment (moisture and flooded conditions). The results revealed that soil moisture decreased from silt floodplain to the reed floodplain. The density of soil seed bank of 5 floodplains had no significant difference. In the germination experiment, the species richness and soil seed bank density in moisture group was significantly higher than in the water flooded group, besides, the species richness and seed bank density in soil seed bank of East Dongting Lake Nature Reserve were significantly higher. Moreover, the species richness of ground vegetation was higher than soil seed bank, and the Jaccard similarity index of soil seed bank and surface vegetation in silt floodplain was the lowest. Phalaris arundinacea, Phragmites communis and Miscanthus sacchariflorus only existed in ground vegetation, while Lindernia procumbens and Mazus japonicus only existed in soil seed bank. In conclusion, it is not possible to rely solely on the seed bank transplantation technology to restore vegetation, the seasonal water level change and the specificity of some species should also be put into consideration. Meanwhile, matching targeted hydrological regulation mechanisms and related artificial measures can help to rehabilitate successfully. |
| Key words: Soil seed bank plant diversity ground vegetation Lake Dongting floodplain soil moisture |
