在藻型富营养湖泊中恢复大型水生植物净化水质的物理生态工程——以中国太湖五里湖为例

In the barren lake, algae-type eutrophication lake, fifteen aquatic vascular plants were introduced and vegetated in our enclosures of physical-ecological engineering. The area of each enclosure is 200 m², with length of 40m, width of 5m and depth of 1.8m. From 1995 to 1997, we had successfully vegetated 15 communities with the propagation techniques of pot-culture and sturdy seedling. The communities included floating, leave-floating and submerged macrophytes, such as Altemanthera phyiloxeroides, Eichhomia crassipes, Trapa maximowiczii, Nymphoides peltata, Potamogeton maackianus, P. crispus, Myriophyllum spicatum, Hydrilla verticillata, Elodea nuttallii, etc. These aquatic macrophytes not only adapted themselves to the environment but also purified the lake water.     

大型水生植物—藻类混合型富营养湖泊的生态管理模式——以固城湖为例

Lake Gucheng is located in the southeast of Nanjing, with an area of 24.3 km², an average depth of 2 meters. The macrophytes of the lake were used to be abundant and their biomass was about 4.96 mg·m^-2. The annual average contents of total phosphorus (TP), total nitrogen (TN), PO^3- -P, COD_Mn and BOD₅ 0.03, 1.31, 0.005, 3.61 and 1.46 mg·L^-1, respectively. Thus, the water quality of this lake is quite well. Recently, the water quality in pari of the lake became worse because of some unreasonable exploitation and utilization of bioresources. The interactions between phytoplankton (N₁), macrophyte (N₂), fish (N₃), crab (N₄) were studied here. The macrophyte has great influences on both phytoplanktons, fish and crab, controlling the water quality and maintaining the fishery productivity. On the other hand, the phytoplankton, fish and crab also influence the macrophyte. It is key method of ecological management to maintain the macrophyte by fishery culture. Therefore, a modified Lotka-Volterra model has been established to estimate the interaction between N₁, N₂, N₃, N₄ and the influences of some water environmental parameters on these aquatic organism, environmental and economic effect. The main model consists four compart-mental models and four submodels, involved 12 external variables, 8 state variables, 19 universal constants and 11 parameters. The values of most parameters were found from our experiments and calibrated by the model and actually measured data. The model has been validated by comparison the computed and experimental data of phytoplankton and macrophyte. The theoretical outputs showed a good agreement with the measured data. This model predicated that if the standing crop offish and crab was higher than 2.65 ·m^-2 during springtime in this lake, macrophytes would not grow, chlorophyll a content would arrive 34.8 mg·m^-3 and the water quality would decrease. If the macrophyte grow well, the maximum fishery productivity would be about 1 600 t. In this case, the annually averaged phytoplankton chlorophyll a content should be 3.69 mg·m^-3, which is lower than the criterion (10 mg·m^-3) for eutrophic state. From 1991 to 1996, Lake Gucheng was managed with this model, its water quality maintain quite well, chlorophyll a content decreased from 3.51 (1991) to 1.89 mg·m^-3 (1994). Meanwhile, the fishery productivity increased and the economic effect heightened year by year.     

冬季富营养化湖泊中水生植物的恢复及净化作用

秋末冬初大多数水生植物处于衰亡期,在透明度较低的富营养化湖泊中引种和恢复水生植物往往十分困难,借助物理生态工程技术,秋末冬初在重富营养化湖泊中新建的1000m^2围隔内,引种漂移植物和沉水植物;利用群落间的相互作用及人工干预,若干种水生高等植物不仅能够引种存活,而且能够快速提高水体透明度、改善水质,引种水生高等植物3周后,有水生高等植物的围区内水体透明度提高一倍,并长期保持在较高水平,6周后,有植物围区内水体TN浓度比对照围区及开敞水域分别降低43．7％和59．4％,TP分别降低50．3％和57．0％;6个月后,TN分别降低61．6％和79．7％有植物围区较开敞水体降低72．9％。     

运营高铁线上水准融合测量方法研究

本文提出了一种将运营高铁线上二等水准复测、CPⅢ高程复测、线上沉降监测等三项水准测量工作进行高度融合的方法,制定了科学合理的外业操作和内业数据处理的操作流程、关键技术环节,解决了运营高铁天窗时间短、天窗数量有限、工期紧、工作量大等不利条件下如何保质保量高效按期完成上述三项工作的难题。     

干旱对芦苇幼苗生长和叶绿素荧光的影响

盆栽试验研究了芦苇幼苗在不同土壤含水量条件下的形态结构、生物量动态、质膜透性、叶绿素含量和叶绿素荧光动力学参数.结果表明,芦苇幼苗高度、株高、基径、地上生物量随土壤含水量的减少而递减.芦苇幼苗通过个体变小、叶片数量和面积减少、生长速率减缓等适应性策略来降低蒸腾量,利用有限的可利用水分维持生命活动,达到了植物叶片水分含量与土壤可利用水分的平衡.不同强度干旱均使叶绿素含量降低,叶绿素a/b值随土壤含水量的降低而升高,减少了叶片对光能的捕获,降低光合机构遭受光氧化破坏的风险,是芦苇幼苗适应干旱的一种光保护调节机制.干旱还导致了芦苇叶片细胞膜脂过氧化,细胞质膜透性增加,重度干旱时细胞质膜透性达29.3%.PSII最大量子产量(Fv/Fm)、光化学荧光淬灭系数(qP)、PSII的非循环光合电子传递速率(ETR)下降,芦苇通过非光化学淬灭(qN)的上升保护PSII.     

健康水生态系统的退化及其修复——理论、技术及应用

由于人口增加和工农业生产的发展,人类赖以生存的淡水生态系统日益退化,特别是富营养化问题,已严重威胁社会经济的持续发展和人类健康,如何在强污染负荷下修复水生态系统具有重大理论和现实意义,本文总结了自1990年以来在淡水湖泊中进行的物理生态工程（Physico-Ecological Enginnering ,PEEN)实验研究实践,主要结论O 为：（1）地表水环境治理的主要目标是修复为稳定健康的水生态系统;（2）主要方法是与污染源治理相结合实践物理生态工程IPEEN）和生物环保产业（Bio-Environmental Enterprise,BEE);(3)实现目标的主要途径是星火燎原,从局部到大范围乃至全流程;（4）实现目标的主要关键是抓住四个环节（4M）;高等水生植物（Macrophyte),宏观颔生学（Macro-bioimitation), 微生物（Microorganism),及管理（Management).(5)山清水秀,人杰地灵,社会经济生态协调发展的美好未来有可能在不远的将来实现。     

湖泊藻型富营养化控制——技术、理论及应用

湖泊富营养化防治走过了从控制营养盐、直接除藻、到生物调控、生态工程及生态恢复等艰难历程,各国为此投入了巨额资金、然而收效甚微,富营养化依然是全球性重大水环境问题。回顾和分析富营养化湖泊治理研究与实践的成功经验与失败教训,无疑将有助于采取更切实可行的技术有效控制湖泊富营养化。综观全球营养养化治理研究成果,不难看出,富营养化是一个典型的生态问题,生态问题只有用生态学方法解决。在全湖性富营养化难以快速根治的情况下,如何集中技术优势和有限财力,优先解决对人类生活影响较大的局部水域富营养化问题,逐步修复受损的湖泊生态系统,提高水体自净能力、改善水体环境质量并建立湖泊健康生态系统。     

南京秦淮河叶绿素a空间分布及其与环境因子的关系

近年来,流动的河流开始陆续暴发藻类水华,河流的水华现象是继湖泊水华现象之后又一倍受关注的科学问题.秦淮河水体污染严重并于2010年8月和9月间暴发水华.采用2010年8月15日和9月8日的秦淮河野外调查数据,对秦淮河水体叶绿素a的空间分布特征及其与环境因子的相关关系进行研究.结果表明,从上游到下游,秦淮河水体叶绿素a含量的分布表现出一定的空间差异性,平均值为73.7μg/L,其中马木桥样点的叶绿素a含量最高(184.52μg/L);秦淮河水体氮磷比为26.86,水体叶绿素a浓度的对数与TP的对数呈正相关,与氮磷比的对数呈负相关,表明磷可能是秦淮河蓝藻生长的主要影响因子;河流水体叶绿素a浓度与pH和DO呈极显著正相关,与NO 2--N呈显著相关,而与NH 4+-N、NO 3--N和TN无显著相关.     

太湖人工生态系统中氮循环细菌分布

对太湖五里湖的以水生高等植物为主的湖泊人工生态系统,用最大可能数法,测定了该系统内各种生态类型水生高等植物群落内的４类氮循环细菌的分布。结果表明反硝化细菌的最大可能数,在水生高等植物群落内水体中较敞水区湖水高２－５个数量级差异极显著;漂服植物各落内水体的反硝化细菌ＭＰＮ值较沉水和浮叶植物群落内水体高２－３个数量级,差异极显著;     

太湖贡湖湾水生植被分布现状(2012年)

贡湖湾是无锡和苏州两市的重要水源地,随着近些年太湖水质的急速恶化,贡湖湾蓝藻暴发现象日益严重,危及饮水安全.为提供贡湖湾水资源管理的理论依据,于2012年开展贡湖湾水生植被野外调查.对8个断面进行为期5天的调查,结果表明:(1)共记录贡湖湾水生植物20科27属34种,单子叶植物和沉水植物分别为优势分类群和生态型;(2)贡湖湾水生植被分布区面积占总水域面积的45.35%,为典型半草型湖泊;(3)共有8种水生植物群落分布,其中马来眼子菜群落分布区面积和生物量最大;(4)贡湖湾水生植被总体表现出北部无水生植被分布,东部生物量高、群落及物种组成复杂,其他区域生物量小、群落组成单一的分布格局.水质恶化和插网捕鱼对贡湖湾水生植被分布现状存在影响,过度清淤可能是造成北部水域裸露的原因.结合贡湖湾水生植被分布现状分析结果,建议在贡湖湾水生植被管理中要开展北部裸水区植被修复,促进湾口区域马来眼子菜群落生长,加强对"引江济太"工程上游来水和贡湖湾水质的监测,并注重外来入侵植物尤其是水盾草群落的监测.