白洋淀湿地营养物质时空分布规律及退化表征初步研究
文献类型：学位论文
| 作者 | 王亮 |
| 学位类别 | 博士 |
| 答辩日期 | 2010 |
| 授予单位 | 中国科学院研究生院 |
| 授予地点 | 北京 |
| 导师 | 尹澄清 |
| 关键词 | 湿地退化 wetland degradation, enzyme, phosphatase, eutrophication, Land/water ecotones 湿地酶 greenhouse gas 磷酸酶 水陆交错带 温室气体 |
| 中文摘要 | 湿地是地球上最重要的生态系统之一，在生物圈中起着不可替代的作用，并为人类的生产、生活提供多种资源，具有巨大的生态服务功能。但是由于人类对湿地的不合理利用，世界范围内湿地退化现象严重。本博士论文以白洋淀为例，调查退化湿地内营养物质的时空分布规律；并从酶学角度出发，多角度地研究湿地内污染物质及酶活性时空分布规律；探讨营养物质时空分布差异与酶活性时空分布规律间的耦合机制，结合宏观及微观指标探求湿地退化的表征。研究的主要结论如下： 1) 白洋淀湿地内部氮、磷等营养元素含量时空差异显著。以水体总磷为例：最大值为3.86 mg/L出现在河口区域，最小值为0.14 mg/L出现在湿地内部区域；从河口区域到湿地内部总氮及土壤总磷含量逐渐减少。从时间变化看从3月份至8月份水体总磷含量逐渐增加，8月份之后水体总磷含量逐渐减低。白洋淀水体叶绿素含量4.5-86.1 g/L，3月份开始水体叶绿素含量基本呈现逐渐上升，8月份达到最大值。白洋淀水体总磷含量平均值为1.60 mg/L，属于富营养化湖泊。 2) 白洋淀湿地中土壤酶表现出显著的空间分异规律。在垂直层面上，表层土壤的磷酸酶活性大于中下层土壤酶活性。沿采样点水平空间分布上，污染较高的河口区域土壤磷酸酶活性较低，而污染较小的中心区域土壤磷酸酶活性较高。 3) 磷酸酶活性及其限制因子可以反映湿地营养状态。和世界很多湿地比较，由于人为污染导致白洋淀湿地土壤总磷含量很高（0.604 g/kg），土壤CP比例小于其它湿地。通过碳添加实验表明，白洋淀是一个碳限制性湿地。相关分析表明，在这样的湿地里，磷酸酶活性与总磷含量不相关，而与有机质含量及CP比例显著相关。不同营养条件下磷酸酶活性的限制因子会发生改变，从而可能表征湿地营养状态。 4) 受污染严重地区温室气体甲烷排放量大于污染较轻区域，这说明大量营养盐输入可能导致碳矿化速率加大。 5) 岸边带可以有效的截留并降解污染物质。岸边带是污染物质降解热区，而且最高值均出现在陆地区域1 m处，这表明水陆交错带陆地区域1 m处是污染物质降解的重要区域。水陆交错带对营养物质有强烈的截留作用，可以净化水质。 |
| 英文摘要 | Wetland is one of the most important ecosystems on the earth and it plays an irreplaceable role in the biosphere. Wetlands provide various natural resources for human and they have great functions of ecological services. Because of the excessive exploitation and the unconscionable uses, the declining problem of wetlands is serious and it has been drawn great attentions worldwide. In this study, Baiyangdian wetlands were chosen to investigate the spatio-temporal distribution of nutrients and the relationship between enzyme activities and nutrient elements. Meanwhile, the characterization of wetland degradation based on macro and micro indicators was studied. The main results are as follows: 1) There were spatial and temporal differences of nitrogen, phosphorus and other nutrient indices in Baiyangdian wetland. The highest value of TP content in water was in the river mouth area (3.86 mg/L), and the lowest was in the central part (0.14 mg/L). From March to August, the water TP content gradually increased, and that decreased from August to the winter. Water chlorophyll contents were between 4.5g/L and 86.1g/L, with the highest value in Augest. The average value of total phosphorus in water was 1.60 mg/L, the Baiyangdian was a eutrophic wetland. 2) There were significant vertical and horizontal variations in phosphatase activity in Baiyangdian wetland soil. The enzyme activities in surface soil layer were significantly higher than those in middle and bottom layers. The phosphatase activity increased from the river mouth area (the seriously polluted place) to the central part (the less polluted place) of the wetlands. 3) Phosphatase activity and its limiting factors reflect the state of wetland eutrophication. In the Baiyangdian, the soil TP contents（0.604 g/kg）were higher than many wetlands reported in the other parts of the world and the C:TP ratio was less than the others. With the glucose addition experiment, it was found that the Baiyangdian wetland was a carbon limited wetland. In Baiyangdian wetland, soil PHA was positively correlated with soil TOC and C:TP ratios, but it had no significant relationship with TP level. It was found that in different nutrient condition the limiting factors of phosphatase activity would change, so hosphatase activity associated its limiting factors probably reflect the state of wetland eutrophication. 4) In the serious polluted place methane (CH4) fluxes was high than less polluted place, the result indicated in the high polluted place the carbon mineralization was increased. 5) The experiment in Baiyangdian wetland indicated that Land/water ecotones exhibited a strong filtrating function. T-test result showed that the landward 1 meter spot away from the water-land interface was quite different from the other spots, and 1 meter spot was the hot spot where great biochemical change happened. The results indicated that the ecotones in Baiyangdian wetland possessed strong retention capacity on allochthonous nutrients, and could act as buffer zones to protect the lake water. |
| 源URL | [http://ir.rcees.ac.cn/handle/311016/35020]  |
| 专题 | 生态环境研究中心_环境水质学国家重点实验室 |
| 推荐引用方式 GB/T 7714 | 王亮. 白洋淀湿地营养物质时空分布规律及退化表征初步研究[D]. 北京. 中国科学院研究生院. 2010. |
入库方式： OAI收割
来源：生态环境研究中心
浏览0
下载0
收藏0
其他版本
除非特别说明，本系统中所有内容都受版权保护，并保留所有权利。