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1.
云贵高原湖泊夏季浮游植物组成及多样性   总被引:2,自引:2,他引:0       下载免费PDF全文
浮游植物是水生生态系统中重要的初级生产者,对维持水生态系统的平衡起着十分重要的作用.根据2008年云贵高原湖泊丰水期浮游植物调查数据,系统地分析了云贵高原13个湖泊中浮游植物的种群密度、生物量、组成及其多样性.云贵高原13个湖泊中共鉴定出浮游植物7门109种(绿藻52种、蓝藻23种、硅藻20种、其他14种).13个湖泊浮游植物Shannon-Wiener指数在0.5-2.2之间,其值大小与单个环境因子无显著相关.相关分析发现浮游植物总量与总氮、总磷、CODMn、硝态氮含量显著正相关,物种丰富度与总氮、总磷(0.1mg/L范围内)、CODMn含量亦显著正相关.另外,研究也发现各湖泊间浮游植物组成的相似性与各湖泊间营养状态差异显著负相关.由此可见,湖泊的营养状态不仅影响浮游植物的总量、组成以及物种丰富度,而且也影响各湖泊物种组成的相似性.  相似文献   

2.
武汉月湖水生植被重建过程中浮游植物的动态变化   总被引:3,自引:0,他引:3       下载免费PDF全文
2004年12月-2005年5月武汉市月湖水生植被重建过程中,对浮游植物进行逐月调查.结果表明,在营养盐浓度较高的条件下,浮游植物仍保持较低的生物量和密度,浮游植物的生长与温度保持一定的相关性,但与湖水营养盐浓度并不存在相关关系.菹草和伊乐藻能使水体的透明度保持较高的状态.浮游植物主要由隐藻和硅藻组成,能形成水华的一些常见种类并未随温度升高而出现,可能与这两种沉水植物的存在改变了浮游植物的群落结构有关.因此,在水温较低的冬季和春季进行水生植被重建是富营养化湖泊治理的有效途径.  相似文献   

3.
浅水湖泊中的初级生产者主要由分布在底栖生境中的底栖植物和生活在敞水生境中的浮游植物组成.底栖植物主要包括维管束沉水植物和底栖藻类等,浮游植物则主要为浮游藻类.贫营养浅水湖泊湖水营养盐浓度低,透明度高,底栖植物因能直接从沉积物中获取营养盐,往往是浅水湖泊的优势初级生产者.随着外源营养盐负荷的增加,湖水中的营养盐浓度不断升高,浮游植物受到的营养盐限制作用减小,加上其在光照方面的竞争优势,逐步发展成为湖泊的优势初级生产者,湖泊逐步从底栖植物为优势的清水态转变为浮游植物为主的浑水态,即稳态转换.在稳态转换过程中,浅水湖泊生态系统结构与功能发生了一系列变化,本文综述了浅水湖泊沉积物性质和生物(浮游植物、底栖植物、底栖动物和鱼类等)群落结构的变化,分析了这些变化对底栖植物、浮游植物之间竞争优势和底栖敞水生境间磷交换的影响,探讨了富营养化驱动的底栖敞水生境耦合过程变化和稳态转换机理.了解浅水湖泊底栖敞水生境耦合过程与稳态转换机理对富营养化浅水湖泊修复有重要意义.富营养化浅水湖泊修复实际就是重建其清水态,在制定修复目标时应该关注评价清水态的指标,如透明度、浮游植物生物量、底栖植物的覆盖度或优势度等.在开展湖泊修复技术研发与工程应用时,应该重点关注对底栖敞水生境耦合有重要影响的关键技术,如沉积物磷释放和底栖生物食性鱼类控制以及底栖植物(尤其是沉水植物)恢复等有关技术.  相似文献   

4.
太湖北部滨岸区水生植被自然修复观测研究   总被引:13,自引:2,他引:13  
1997-1999年连续3年对太湖北部围隔实验区水生植被自然修复过程的观测表明,大型富营养化浅水湖泊滨岸水域,通过实施围隔保护等途径,土著水生高等植物如荇菜、菱等能够在次生裸区水域自然修复生长。1998年夏季荇菜、菱种群覆盖面积分别达到围隔保护区总面积的14.3%和12.7%。伴生种群有马来眼子菜、狐尾藻和苦草等。分析了人为刈割、水产养殖对水生高等植物自然修复进程的影响。据此提出治理太湖等大型浅水湖泊富营养化污染的对策。  相似文献   

5.
太湖梅梁湾富营养化过程的同位素地球化学证据   总被引:4,自引:0,他引:4  
以浅水湖泊太湖为研究对象,通过湖泊水体、水生生物同位素以及相应湖泊水体营养指标的比较分析,并根据梅梁湾钻孔沉积物TN,TP,TOC,C/N,δ15N,δ13C等多项指标记录,恢复了湖泊富营养化过程.研究结果表明,不同湖区植物碳、氮同位素值和水体NH4+的δ15N值变化反映了植物组成和营养水平的差异.梅梁湾水体NH4+的δ15N和水环境参数不同月份的变化反映了外部营养载荷的输入对湖泊环境有明显的影响.1950~1990年湖泊沉积物有机质碳、氮同位素同步变化的趋势说明湖泊初级生产力的增长和湖泊逐渐富营养化的过程,而1990年之后二者之间反相关关系的出现表明在富营养条件下,大量浮游植物生长对富15N的无机氮的吸收及表层沉积物有机质分解和反硝化作用,代表湖泊富营养化加剧.以同位素示踪,并结合元素地球化学指标变化,将太湖梅梁湾富营养化过程分为三阶段,以20世纪50年代和20世纪90年代为营养状态的转换时段,揭示了人类活动不断加强的影响,与近50年来的湖泊环境监测结果一致.  相似文献   

6.
基于浓缩法的浮游植物定量数据稳定性与可靠性分析   总被引:1,自引:1,他引:0  
牛海玉  陈纯  韩博平 《湖泊科学》2015,27(5):776-782
浮游植物是水生生态系统中重要的初级生产者,相对准确地定量它们的数量是进一步进行水质评价和生态功能分析的基础.通过采集处于不同营养状态的水库和不同处理的围隔中的浮游植物,研究影响浓缩法定量浮游植物的因素,了解如何通过浓缩法来合理地定量浮游植物.分析浓缩倍数、样品的显微镜计数量、水体营养状态对浮游植物丰度、生物量及群落多样性等定量参数稳定性的影响,同时比较单个不同水体中重复(或平行)样品之间浮游植物丰度的差别.结果表明,基于浮游植物的显微镜计数效率与定量数据稳定性的综合考虑,选择计数4片×10格/片即可基本保证定量数据的稳定性;在保证正常镜检的基础上,考虑水体营养状态适当增加浓缩倍数能够提高定量数据的可靠性;在特别依赖生物量或稀有种进行水质评价时,处于不同营养水平的水体均需要增加样品的平行数来提高定量数据的可靠性.  相似文献   

7.
长江下游湖泊水生植物现状及与水环境因子的关系   总被引:4,自引:3,他引:1  
研究水生植物分布与环境因子的关系可为富营养化湖泊的生态修复提供重要科学依据.通过对长江下游10个不同营养水平湖泊的水生植物群落组成和环境状况进行野外调查,研究了长江下游湖泊主要水生植物分布状况及水环境因子对水生植物分布的影响.调查发现长江下游10个代表性湖泊主要水生植物共计6科7属11种,主要生活型为沉水植物.水生植物群落组成与环境因子的冗余分析结果显示,总氮、pH值和水深是显著影响这些不同营养水平湖泊水生植物分布的主导因子.  相似文献   

8.
通过长江中游龙感湖和太白湖浅钻沉积硅藻的高分辨率分析研究,利用区域硅藻-总磷转换函数结果,重建了这两个湖泊的硅藻植物群演化和湖水总磷变化的历史.龙感湖在过去200年来,总磷浓度变幅较小(在36~62μg/l之间),湖泊一直维持在中等营养态水平.硅藻组合演替反映了草型湖泊的变化特点,其中19世纪期间,相对增高的总磷浓度与底栖硅藻种的增多对应;20世纪初期以来,附生种含量的阶段性上升指示了水生植被不断发育,水体总磷也表现出两次阶段性降低过程.太白湖在1953年前,总磷浓度稳定在50μg/l左右,硅藻由兼浮游类型Aulacoseira granulata迅速向附生类型组合演替,指示了水生植被的一次快速扩张;1953~1970年期间,附生种类的大量减少和浮游种的逐渐增多指示水生植被覆盖度明显减少,推导的湖水总磷第一次出现明显的增高趋势,标志着湖泊富营养化的发生;20世纪70年代以来,浮游种类的持续增多,该湖已处于富营养状态.进一步对比分析表明,水生植被对水体营养物质的内在调节和净化功能.两个湖泊在20世纪60年代以来环境演化发生分异,反映了湖泊对人为干扰响应的两种方式.太白湖沉积硅藻清楚地记录了湖泊由草型向藻型阶段转变的过程,其过渡状态的总磷浓度变化范围,可能就是两种稳定态系统发生变化的营养临界区间(总磷浓度在68~118μg/l之间),该初步推论尚需其它富营养藻型湖泊的沉积记录加以证实.不同湖泊过去湖水总磷的重建及水生植被演化的比较研究,为富营养湖的生态治理提供了科学依据.  相似文献   

9.
冬季富营养化湖泊中水生植物的恢复及净化作用   总被引:40,自引:2,他引:40  
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%。  相似文献   

10.
针对武汉东湖存在营养状态梯度的5个子湖(郭郑湖、汤菱湖、团湖、庙湖、水果湖),结合"空间换时间"理论,研究湖泊富营养状况改善过程中浮游植物群落对环境因子的响应.全年调查期间,各子湖综合营养状态指数分布范围为45.4~76.8,浮游植物密度及生物量变化范围分别为2.03×106~245×106 cells/L和0.819~19.9 mg/L.冗余分析结果显示,浮游植物的物种分布与水温、总氮、透明度、总溶解性固体、氨氮呈显著相关.采用多元逐步回归分析构建浮游植物密度、生物量与环境因子之间的最优响应方程,结果显示,总氮、水温是影响浮游植物密度的主要因子;对于浮游植物生物量而言,总磷、总氮浓度降低能够降低浮游植物生物量.通过对富营养程度改善进程中浮游植物群落组成的动态变化进行分析,发现浮游植物密度及生物量显著下降,但物种组成及生物多样性并未发生明显转变.此外,浮游植物物种多样性与水体富营养水平梯度并不呈现简单的线性相关.因此,在对富营养化湖泊进行修复时,应制定短期修复与长期维护双重措施,同时应重视生物多样性的重建,进而达到理想的修复效果.  相似文献   

11.
Phytoplankton and zooplankton were monitored during 2 years in four eutrophic shallow lakes (two turbid and two clear water) from two wetland reserves in Belgium. In each wetland, phytoplankton biomass was significantly higher in the turbid lake than in the clear water lake. Although total macrozooplankton biomass and the contribution of daphnids to total zooplankton biomass was comparable in the clear water and the turbid lakes, the grazing pressure of macrozooplankton on phytoplankton as estimated from zooplankton to phytoplankton biomass ratios was higher in the clear water lakes. Estimated grazing by daphnids in the clear water lakes was always high in spring. In summer, however, daphnid biomass was low or daphnids were even absent during prolonged periods. During those periods phytoplankton was probably controlled by smaller macrozooplankton or by submerged macrophytes through nutrient competition, allelopathic effects or increased sedimentation rates in the macrophyte vegetation.  相似文献   

12.
湖泊生态系统的水鸟监测意义   总被引:5,自引:3,他引:2  
张淑霞  董云仙  夏峰 《湖泊科学》2011,23(2):155-162
水鸟的多样性及其变化趋势是保护水鸟必需的信息,也是其柄息湿地环境质量的指示因子之一.本文综述了水鸟与湖泊生态系统关系的研究成果,认为水鸟的物种多样性与丰富度可以快速反映湖泊的水生植物、鱼类的生物量和湖泊水位、营养状况的变化,集群繁殖的食鱼水鸟可用于湖泊生态系统中持久性有毒化学污染物的生态监测;同时阐述了水鸟通过取食水生...  相似文献   

13.
Inlay Lake is the second largest natural lake in Myanmar. Located in Shan State, in the eastern part of the country, it is a known biodiversity hotspot. The lake is negatively affected by an increasing local human population and rapid growth in both agriculture and tourism. In recent decades, several studies have listed faunistic and floristic groups in Inlay Lake, but there is still a general lack of knowledge about the aquatic macrophyte and phytoplankton community composition and abundance, and their interactions. To fill this knowledge gap, field surveys of biological and physical and chemical parameters were carried out in the period 2014–2017. They show that Inlay Lake is a shallow, clear water and calcareous lake, with nutrient concentrations indicating mesotrophic-eutrophic conditions. However, close to the shore, nutrient concentrations are generally higher, reflecting pollution from inflowing rivers, shoreline villages and floating gardens. Both the richness and abundance of aquatic macrophytes in Inlay Lake were high, with several species forming extensive stands in most of the lake over the whole survey period. Total phytoplankton and cyanobacterial biomass were low, but cyanobacteria included toxin-producing strains of Microcystis, suggesting that cyanobacterial and total phytoplankton biomass need to be kept low to avoid potentially harmful cyanobacterial blooms. Submerged macrophyte abundance and phytoplankton biomass were inversely correlated in the heavily vegetated northern lake area. Our survey suggests a great importance of the submerged macrophytes to the general water quality and the clear water state in Inlay Lake. Maintaining high macrophyte abundances should therefore be a goal in management strategies, both for Inlay Lake and other lakes in Myanmar. It is highly desirable to include macrophytes and phytoplankton in the lake monitoring in Myanmar.  相似文献   

14.
To test if phytobenthic algae provide additional important information to macrophytes and phytoplankton for lake monitoring, we sampled two large lakes in Norway. In each lake, we analyzed water chemistry and phytoplankton above the deepest site, recorded macrophytes and non-diatom phytobenthic algae at 20 sites around the shoreline and estimated site-specific nutrient input from land cover. Since no ready-to-use phytobenthos index exists for lakes in Norway, we tested the PIT index developed for rivers, commonly perceived signs of disturbance such as high algal cover, and taxon richness as well as similarity patterns. Both lakes were nutrient poor, but had potential local nutrient inputs (villages, agriculture). In neither of the lakes did phytobenthos indicate a worse overall ecological status than macrophytes and phytoplankton. Our data therefore, did not suggest that it would be useful to add phytobenthos into surveillance monitoring of lakes in Norway. There was a loose correlation between macrophyte and phytobenthic site-specific taxon richness and similarities. This means that macrophytes and phytobenthos do indeed give partly redundant information. High algal cover was found at sites with both high and low phosphorus input. Using algal cover as indicator of site-specific nutrient input is therefore overly simplistic. Urban and cultivated areas were associated with a more eutrophic PIT. This indicates that the PIT, despite being developed for lotic waters, may be used to detect site specific nutrient input in lakes.  相似文献   

15.
Variations of the trophic status of lakes Batorino, Myastro, and Naroch were analyzed over a long period of 1978–2013. The lakes form a system of interconnected water bodies with a wide range of trophic states. In the period under consideration, the trophic conditions in the lakes varied from highly eutrophic (Lake Batorino) to oligotrophic (Lake Naroch), making it possible to analyze the long-term changes in the trophic state of the lakes with the use of different variants of evaluating the Carlson index (trophic state index, TSI), to assess the relationship between the three versions of the index with one another, with phytoplankton biomass, and with hydroecological characteristics, such as the concentrations of total N, seston, and organic matter and biochemical oxygen demand. The possibility to evaluate the index by other characteristics, including phytoplankton biomass, was also considered.  相似文献   

16.
Ecological restoration of eutrophic lakes using aquatic macrophytes is an important and practical technology. Here, we investigated the response of phytoplankton and zooplankton to a large-scale 2015-built aquatic macrophyte enclosure (AME, 200,000 m2) screened of by a PVC net in Baima Lake, a eutrophic lake, from spring to autumn of 2019. AME significantly improved water quality by increasing water transparency, and reducing total nitrogen, total phosphorus, and chlorophyll-a content during the growing season. AME significantly decreased phytoplankton abundance and biomass and marginally increased zooplankton abundance and biomass. Phytoplankton and zooplankton communities were closely related to environmental factors, such as water temperature, conductivity, total phosphorus, chemical oxygen demand, and chlorophyll-a inside and outside the AME. The zooplankton:phytoplankton biomass ratio inside was slightly higher than outside the AME. Zooplankton and phytoplankton biomass were significantly positively correlated inside and outside the AME, as were chlorophyll-a and total phosphorus. We found phosphorus to be a key factor limiting primary productivity in Baima Lake, and that bottom-up effects were the main driver to control phytoplankton in the AME. Using aquatic macrophytes to reduce nutrient loads is an effective way to manage eutrophication in Baima Lake.  相似文献   

17.
Most existing studies on the algal communities of acid lakes are based on environments that have been caused by anthropogenic disturbances. Such lakes have a different origin compared to the natural acidic lakes and could be expected to differ also in the mechanisms controlling phytoplankton and trophic status. Planktonic community in Lake Caviahue is somewhat diverse in spite of the low pH of the water. Algae have a distinctive vertical distribution: the values of phytoplankton biomass remain constant throughout the water column and at times were highest in the upper end of the hypolimnion, forming a maximum or a layer of chlorophyll a at depth. The goal of this work was to investigate the factors influencing the seasonal and vertical distribution of phytoplankton. The lake was sampled between the years 2004 and 2006. Physical, chemical and biological parameters at different depths throughout the water column were determined. The interrelationships between environmental variables at different sampling dates were analyzed using an integration of multivariate matrices, multiple factor analysis, to analyze any joint partnerships in the samples. We found that phytoplankton biomass is dominated by Keratococcus rhaphidioides. With regard to zooplankton, we found a single species of rotifers (Philodina sp.). The two arms of the lake and the depths have different behaviours showing differences in the arms' conductivity, dissolved oxygen and pH. The more superficial layers were characterized by high values of phytoplankton and zooplankton biomass, organic and inorganic carbon, dissolved oxygen and pH. The deeper layers showed high values of chlorophyll a, ammonium and phosphorus (dissolved and particulate). From the multivariate analysis the relationships of the each algal species with pH, as a possible indicator of the degree of “acidophilia”, could be extracted.  相似文献   

18.
重建沉水植物群落是修复浅水富营养化湖泊的关键.河蚌可改善水下光照条件、促进沉水植物生长,因此放养河蚌常被用于沉水植物群落恢复的并行手段.河蚌是鳑鲏产卵的重要基质,因此河蚌可能促进鳑鲏种群发展,而鳑鲏对水生态系统的影响还尚不清楚.本研究以密刺苦草、大鳍鱊和背角无齿蚌为研究对象,通过中宇宙试验研究河蚌和鳑鲏对附着藻的影响,以及鳑鲏对水质和沉水植物生长的影响及机理.结果发现:鳑鲏显著增加了水体总磷、总溶解性磷、总悬浮物和叶绿素a浓度,而对总氮和总溶解性氮浓度的影响不显著.河蚌对苦草的相对生长率、总株数、根冠比及苦草最大叶长均无显著影响,而显著增加了苦草的单株平均生物量,这可能与河蚌组较高的附着藻生物量有关.鳑鲏未显著影响河蚌与苦草间的关系,但鳑鲏的出现显著增加了附着藻类生物量;此外,鳑鲏还降低了苦草的根冠比,而增加了苦草的最大叶长,这可能与鳑鲏引起的营养盐和叶绿素a浓度升高,以及植物表面附着藻生物量显著升高有关.鳑鲏属于小型杂食性鱼类,在长江中下游地区分布广泛,与沉水植物关系密切,且易在修复后的湖泊中形成优势鱼类,因此在湖泊修复和管理中应加强此类小型杂食性鱼类的监测与管理.  相似文献   

19.
武山湖是紧邻长江的通江型富营养化湖泊,是国家级湿地公园.为切实了解该湖在以鲢、鳙养殖为主的情况下浮游植物结构特征,于2017年9月-2018年8月对其浮游植物群落结构特征及水质开展了监测.监测结果表明武山湖水质全年处于轻度富营养到重度富营养水平之间;12次共采集浮游植物7门100种(属),浮游植物优势种共有23种,其中蓝藻门有9种,绿藻门有8种,硅藻门和隐藻门各有3种.夏季和秋季蓝藻门优势种最多且优势度高,冬季和春季绿藻门和硅藻门优势种多且优势度高.武山湖浮游植物每月优势度最大的种类主要有蓝藻门微囊藻和细小平裂藻、绿藻门小球藻以及硅藻门小环藻.浮游植物生物量峰值出现在6月,达34.77 mg/L;丰度峰值出现在7月,达341.46×106 cells/L.冗余分析(RDA)和线性相关分析均表明浮游植物丰度和生物量与总磷、温度和pH均呈显著正相关,且蓝藻门生物量和丰度以及优势属与总磷和温度均呈显著正相关.研究结果表明武山湖浮游植物丰度和生物量在夏季均很高,发生蓝藻水华的风险较大.相对于氮,磷是更重要的限制浮游植物生长的营养元素.  相似文献   

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