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沉水植物对白洋淀湿地环境净化效果的研究

标题: 沉水植物对白洋淀湿地环境净化效果的研究
英文标题: Purification Efficiency of Submerged Macrophytes for the Wetland Environment in Baiyangdian Lake
作者: 任文君
出版时间: 2011-01-01
所在大学: 河北农业大学
关键词: 白洋淀,沉水植物,菹草,水体,植株,底泥,营养指标
英文关键词: Baiyangdian Lake,Submerged macrophyte,Potamogeton crispus,Water,Plant,Sediment,Nutritive value
论文级别: 硕士
学位: 学位论文
导师: 谢建治
专业: 土壤学
提交时间: 2011
摘要: 白洋淀水体富营养化的治理已成为迫切要解决的问题,应采取措施改善和恢复白洋淀的湿地环境.沉水植物是湿地生物多样性赖以维持的基础,它的恢复是水生态环境修复的关键,所以系统研究沉水植物对污染水体所产生的环境效应是必要的.本文通过对白洋淀沉水植物的系统调查,确定菹草为白洋淀沉水植物的优势种群之一,结合其他沉水植物,综合考虑其对白洋淀湿地环境净化的净化效果,揭示环境变化对沉水植物生长的影响,探索植物资源化综合利用模式,为白洋淀草型湖泊生态系统的保护提供理论依据.本文主要开展了以下工作:(1)配制不同氮磷浓度的营养盐溶液,在低,中、高、富和超富营养条件下,对比研究菹草生长体系的水质改善效应;(2)室内静态模拟白洋淀菹草的生长环境,探讨菹草生长体系对白洋淀不同淀区富营养化水体和底泥的净化效果;(3)利用白洋淀现场试验,监测菹草不同生长期白洋淀湿地环境的变化,采集相应生长期的菹草,对其体内多种营养指标含量进行分析,确定白洋淀菹草的最佳收获时间,为菹草的资源化利用提供依据;(4)采用光照室盆栽模拟试验,对比研究不同种类沉水植物生长体系对白洋淀富营养化水质的改善效应.通过上述研究,得到结论如下:(1)菹草在中、高、富和超富营养浓度下长势良好,并对水体氨氮、总氮和总磷具有较好的吸收效果,最低的去除率分别为:88.18%、18.53%和53.15%;菹草植株对总氮的吸收属于超量吸收;对总磷的吸收以沉降吸附为主.菹草-底泥-水体三者间的浓度交换,会使底泥营养成分改变,沉水植物对底泥中氮、磷、有机质含量及底泥向上覆水中氮磷的输送转移均有明显的抑制作用.(2)白洋淀不同菹草生长体系对水体污染物的净化效果存在差异.菹草生长体系的氮磷及CODcr浓度随时间降解的拟合方程表明,在菹草生长体系对水体的净化过程中,水体中污染物浓度与菹草生长时间显著负相关,呈负指数形式衰减.各菹草生长体系对水体中氨氮、总氮、总磷和CODcr的最大去除率分别为:90.97%、73.3%、87.9%和58.25%.(3)通过长期现场监测表明:3-5月初,菹草生长旺盛,各监测点水体中溶解氧含量升高,化学需氧量、氨氮、总氮、总磷和正磷酸盐浓度均随着菹草生物量的增大而大幅下降;菹草种群分布密集区域各项指标明显优于其他区域.同时菹草能够吸收底泥中的氮、磷及有机质,抑制底泥中污染物质的释放.(4)菹草营养指标在各生长期呈现先增高后降低趋势的指标有:粗蛋白、粗脂肪、总磷以及β胡萝卜素,均在菹草指数生长期达到最大值;而粗纤维、粗灰分、钙以及Vc含量在3-6月的监测中呈现逐渐上升趋势.不同的菹草生长期,各采样点菹草粗蛋白含量均大于100g·kg~(-1),粗灰分含量大于140g·kg~(-1),钙和磷含量均大于3.0g·kg~(-1),Vc含量大于140mg·kg~(-1),β-胡萝卜素含量大于310mg·kg~(-1);粗纤维含量低于155g·kg~(-1).菹草营养价值较其他水生饲料高,是鱼、畜禽等理想的饲料.(5)综合菹草自身营养物质含量及水质变化情况,确定理想的收割时间为菹草产生芽殖体后,即5月初.(6)白洋淀其他沉水植物对总氮去除能力大小的顺序为:金鱼藻>黑藻>马来眼子菜>蓖齿眼子菜,其去除率均达到79.4%以上;对总磷去除能力由大到小的顺序为:黑藻>金鱼藻>马来眼子菜>蓖齿眼子菜,其去除率均达到83.59%以上.
英文摘要: Control the eutrophication of Baiyangdian Lake has becamed a problem to solve, should take some measures to improve the environment of the wetland of Baiyangdian Lake. Submerged macrophytes are the key to repair the environment of water. This research investigated the submerged macrophytes of Baiyangdian Lake, and made sure Potamogeton crispus is the preponderant species of Baiyangdian Lake, combine other submerged macrophytes to conside the purification efficiency of submerged macrophytes for the wetland environment in Baiyangdian Lake. Provide theoretical basis to prodect the ecosystem of Baiyangdian Lake.This research mainly on the following job:(1) Made different nutrition liquids of nitrogen and phosphorus, in the condition of low nutrition、middle nutrition、high nutrition、rich nutrition and exceed rich nutrition to compare the improve efficiency to water.(2) Different simulated static systems were built to study the growth of Potamogeton crispus and its effect on removal the nitrogen and phosphorus from eutrophic water and sediment.(3) Taking the Potamogeton crispus collected from Baiyangdian Lake, in different growth periods analyse the wate、nutritive value changes and made sure the best harvest time of Potamogeton crispus.(4) Static simulation tests were carried out in lab to study the effectivenes on the improve water of Baiyangdian Lake.Through the above researches, conclusiones are as follows:(1) Potamogeton crispus in the condition of middle nutrition、high nutrition、rich nutrition and exceed rich nutrition growth well, the lowest removal efficiency of NH4+-N、TN and TP were 88.18%、18.53%and 53.15%. The absorb manner of Potamogeton crispus to TN is exceed, and to TP is sedimentation. Sediment is playing an important role in nutrients removal.(2) Different growth systems of Potamogeton crispus have different Purification efficiency to water. The fitted equations indicated that NH4+-N、TN、TP and CODcr were negatively exponentially decreased with time. The best removal efficiency of NH4+-N、TN、TP and CODcr were 90.97%、73.3%、87.9%and 58.25%.(3) The results showed that Potamogeton crispus biomass increased at the exponential growing stage, the concentrations of dissolved oxygen risd, chemical oxygen demand, ammonia nitrogen, total nitrogen, total phosphorus and orthophosphate levels declined in Baiyangdian Lake.The content in the area with Potamogeton crispus was significantly better than the area without Potamogeton crispus. Potamogeton crispus growth absorbed the nitrogen、phosphorus and organic matter from the sediments, and inhibit the pollutants release from the sediment.(4) In exponential growth phase of Potamogeton crispus biomass increase, the content of crude protein、crude fat、Total P andβ-carotene reached the largest, in the monitoring of month 3-6, the content of Crude fiber, crude ash, calcium and Vc showed a gradually rising trend. The content of crude protein more than 100 g·kg~(-1), the content of Crude fiber below 155 g·kg~(-1), the content of crude fat more than 12 g·kg~(-1) the content of crude ash more than 140 g·kg~(-1), the content of Ca and total P more than 3 g·kg~(-1), the content of Vc more than 140 mg·kg~(-1), the content ofβ-carotene more than 310 mg·kg~(-1), in the whole growth periods of Potamogeton crispus, every sampling site. The nutritive value of Potamogeton crispus more than other hydrophytic feeds, Potamogeton crispus was the most perfect feed to fish and domestic animal.(5) According to the water and nutritive value change, the best season of Potamogeton crispus harvestry is the beginning of May.(6) The order of TN removal ability was: Ceratophyllum demersum、Hydrilla verticillata、Potamogeton malainus、Potamogeton pectinatus, and the removal efficiency more than 79.4%; The order of TP removal ability was: Hydrilla verticillata、Ceratophyllum demersum、Potamogeton malainus、Potamogeton pectinatus, and the removal efficiency more than 83.59%.