【作者】 樊海川；

【导师】 周林飞；

【作者基本信息】 沈阳农业大学 ， 水利水电工程， 2019， 硕士

【摘要】 水生植物恢复是富营养化湖泊生态恢复的重要措施之一,研究水生植物在富营养化水体中发挥的作用对治理人工湿地、湖泊富营养化问题具有重要意义。本文以石佛寺人工湿地几种代表性的水生植物作为研究对象,围绕水生植物的促淤效应与磷的沉积等方面进行研究,通过野外考察和室内实验,分析并讨论不同水生植物对淤积物中磷的含量以及深度变化的影响,同时比较不同淤积物中水生植物的生物量差异,研究淤积物中营养物质对水生植物生长的影响。通过研究,主要得到以下结论:(1)通过在石佛寺人工湿地采集对比4种不同水生植物(荷花、蒲草、芦苇、沉水、浮叶植物的混合)区域和主河道区域的淤积物,研究这不同水生植物对淤积物中TOC含量及淤积深度的影响。结果表明水生植物的促淤效应会使淤积物变得疏松,从而增加淤积物的深度。因水生植物的种植,湿地内淤积物深度约增加了0.261m。总体来看,荷花区域的促淤效应最强,可带来0.101m的淤积深度,芦苇区域0.067m,蒲草区域0.063m,混合植物区域0.030m,同时水生植物通过降低流速、抑制悬移质再悬浮等作用会产生部分非生物淤积量。应将湿地内水生植物的残体及时收割利用,从而减轻整个湿地的生物沉积负担。(2)在石佛寺水库人工湿地采集对比芦苇和蒲草两种不同水生植物区域内的淤积物和生物植株,对比研究不同营养特征淤积物对水生植物生物量的影响。结果表明:淤积物内营养特征与各时期内水生植物的生物量具有一定的相关关系。生长初期,芦苇和蒲草的生物量与淤积物中氮元素(N)和磷元素(P)呈负相关,其中与TP含量的相关性达到显著水平(p<0.05),即较高的淤积物中营养元素含量会对水生植物的生长产生抑制作用;随着水生植物的进一步生长,这种抑制作用逐渐较小,并逐渐转变为促进作用,淤积物中营养元素含量与水生植物生物量的相关关系由负相关转为正相关;水生植物进入成熟期后,芦苇和蒲草的生物量达到最大值,淤积物内TN及TP含量均与水生植物的生物量呈显著正相关关系;之后随水生植物死亡腐解,这种关系逐渐消失。(3)在石佛寺人工湿地采集对比4种不同水生植物(荷花、蒲草、芦苇、沉水、浮叶植物的混合和空白)区域和空白区域的淤积物中磷沉积变化规律及其成因。结果表明水生植物可以有效的抑制淤积物中磷元素的释放,且不同的植物区域磷的沉积特征有所不同,其中芦苇区域淤积物中磷的含量最高,抑制淤积物中磷释放能力较强,蒲草区域中淤积物中磷的含量最低,抑制淤积物中磷释放能力较弱,而无植物的空白区域对淤积物中磷的沉积特性无明显影响。当冬季水生植物开始死亡腐解后,有水生植物种植的区域内淤积物中磷的含量都会有明显的提升。更多还原

【Abstract】 The restoration of aquatic plants is an important measure for the ecological restoration of eutrophic lakes.Studying the role of aquatic plants in eutrophic waters is of great significance for the treatment of eutrophication of constructed wetlands and lakes.In this paper,several representative aquatic plants in Shifosi constructed wetland were studied,and the effects of siltation and phosphorus deposition on aquatic plants were studied.Field investigations and laboratory experiments were conducted to analyze and discuss different aquatic plants in sediments.The effects of phosphorus content and depth change,while comparing the biomass differences of aquatic plants in different sediments,studied the effects of nutrients in the sediment on the growth of aquatic plants.Through research,the main conclusions are as follows:(1)Studying the different aquatic plants in the sediment by collecting and comparing the sediments of four different aquatic plants(mixture of lotus,bulrush,reed,submerged,and floating plants)and main rivers in the constructed wetland of Shifo Temple The influence of TOC content and sedimentation depth.The results indicate that the siltation-promoting effect of aquatic plants can cause the sludge to become loose,thereby increasing the depth of the sludge.Due to the cultivation of aquatic plants,the depth of sediment in the wetland increased by about 0.261 m.Overall,the lotus area has the strongest silt-promoting effect,which can bring a sedimentation depth of 0.101 m,the reed area is 0.067 m,the pupa area is0.063 m,and the mixed plant area is 0.030 m.At the same time,the aquatic plants reduce the flow rate and inhibit the suspended matter.Suspension and other effects will produce some non-biofouling.The residues of aquatic plants in the wetland should be harvested and utilized in time to reduce the biodeposition burden of the entire wetland.(2)The sediments and biological plants in the two different aquatic plants of Phragmites australis and P.humilis were collected and compared in the artificial wetland of Shifosi Reservoir.,and the effects of sediments with different nutrient characteristics on aquatic plant biomass were compared..The results showed that the nutrient characteristics of the sediments had a certain correlation with the biomass of aquatic plants in each period.In the early growth stage,the biomass of the reeds and the grasses was negatively correlated with the nitrogen and phosphorus in the sediments.The correlation with TP content reached a significant level(p < 0.05),that is,the higher nutrient content in the sludge inhibited the growth of aquatic plants.With the further growth of aquatic plants,this inhibition gradually became more Small,and gradually transformed into a promoting effect,the correlation between nutrient content and aquatic plant biomass in the sediment changed from negative correlation to positive correlation.After the aquatic plants entered maturity,,the biomass of reed and raupo reached the maximum,and the contents of TN and TP in the sediments were significantly positively correlated with the biomass of aquatic plants.;this relationship gradually disappears as the aquatic plants die.The nutrient level of silt affects the growth of aquatic plants,mainly in the accumulation of biomass.The growth of different aquatic plants is affected differently,and the biomass of the grass is more correlated with the nutrient content in the sediment.(3)Collecting and depositing sediments in four different aquatic plants(mixtures and blanks of lotus,bulrush,reed,submerged,and floating-leaf plants)and blank areas in the artificial wetland of Shifo Temple to study the phosphorus deposition in different aquatic plants.The impact of features.The results showed that aquatic plants could effectively inhibit the release of phosphorus from sediments,and the phosphorus deposition characteristics of different plant regions were different.Among them,the phosphorus content in the sediments of the reeds was the highest,and the phosphorus release ability in the sediments was strong.The content of phosphorus in the sediment in the Pucao area was the lowest,and the release of phosphorus in the sediment was weak,while the blank area without plants had no significant effect on the deposition characteristics of phosphorus in the sediment.When winter aquatic plants begin to rot and decompose,the phosphorus content in the sediments in areas where aquatic plants are grown will increase significantly.更多还原