| 摘要: |
| 选取江苏王港潮滩的盐蒿滩、大米草滩及互花米草滩,分析这三类滩面的地面以上生物量、初级生产力、动物洞穴参数和沉积物粒度,探讨大米草和互花米草引种区的湿地生态系统相对于盐蒿滩的变化。分析结果表明,互花米草滩的生物量远大于盐蒿滩和大米草滩;单位面积上动物洞穴数量相近,但洞穴大小有一定差异,互花米草滩动物洞穴稍大,数量也相对较多,这可能与初级生产力的提高有关。表层底质的粒径以互花米草滩为最细,盐蒿滩最粗,这种分布状况与互花米草引种前不同,说明互花米草促进了细颗粒物质的堆积。互花米草的引种在江苏海岸具有促淤和提高初级生产力的作用,而它对湿地生态系统的结构和功能的影响需要进一步研究。 |
| 关键词: 大米草 互花米草 潮滩生态系统 江苏海岸 |
| DOI： |
| 分类号: |
| 基金项目:国家自然科学基金资助项目,40476041号 |
|
| TIDALFLAT ECOLOGICAL CHANGES BY TRANSPLANTING SPARTINA ANGILICA AND SPARTINA ALTERNIFLORA, NORTHERN JIANGSU COAST |
|
CHEN Yi-Ning, GAO Shu, JIA Jian-Jun, WANG Ai-Jun
|
|
Ministry of Education Key Laboratory for Coast and Island Development, Nanjing University, Nanjing,210093
|
| Abstract: |
| In order to evaluate the impact of artificially introduced cord grasses on coastal wetland ecosystem of Jiangsu Province, eastern China, a transection on the upper intertidal zone, 950m long spanning three types of vegetation covers (i. e. Suaeda salsa, Spartina angilica and Spartina alterniflora flats), was established at Wanggang, Jiangsu, in a multi-disciplinary investigation. In summer and autumn 2003, surficial sediment and plant samples were collected, the bed morphology was surveyed by leveling, and the size of animal burrows (mainly formed by marsh crabs) was measured in the study area. Grain size was analyzed in laboratory, and above ground biomass of the tidal flat plants, and the distribution patterns of the animal burrow sizes were also studied.
The bed was covered mainly with silty sediments on all the three types of flats. The sediment was finer on Spartina alterniflora flat which is located in lower part of the transection, than on Suaeda salsa and Spartina angilica flats. Before the cord grasses were introduced, the bottom sediment had a coarsening trend from higher part to lower part of the intertidal zone. Therefore, the presence of the cord grass Spartina angilica favors the accumulation of fine-grained materials and has modified the original sediment distribution of the flat.
The above ground biomass of the three different biotic communities shows that the net primary production on Spartina alterniflora flat was the highest, reaching the order of 2×102 gC/m2 in summer and 8×102 gC/m2 in autumn, indicating rapid increase during summer and early autumn. These values were significantly higher than those of the Suaeda salsa and Spartina angilica flats, where the net primary production was in the order of 4×101 gC/m2 in summer and 5×101 gC/m2 in autumn. The growth of the plants on these flats slowed down after July. The facts indicate that the biomass or net primary production on the tidal flat has been enhanced significantly since Spartina alterniflora was transplanted.
Non-parameter test of the animal burrow size (mainly crab burrows) suggests that the burrows on the Suaeda salsa flat were significantly different from those on the Spartina angilica and Spartina alterniflora flats, but there was no significant difference between Spartina angilica and Spartina alterniflora flats. In the summer, the burrows on the Suaeda salsa flat were larger but fewer; in the autumn, the burrows were smaller, with a significant increase in number. Thus, the introduction of the cord grasses has changed the burrow sizes and its seasonal variation of the salt-marsh animals. Nevertheless, the relatively stable distribution of the burrows on both Spartina angilica and Spartina alterniflora flats indicates that the marsh crabs could well adapted to the new environment. However, more studies are required to understand the ecosystem structure and functioning in response to marsh vegetation changes. |
| Key words: Spartina anglica, Spartina alternif lora , Tidal flat ecosystem, Jiangsu coast |
