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1.
利用PFU原生动物群落多样性快速监测北京通惠河水质   总被引:35,自引:0,他引:35  
本文报道了北京通惠河原生动物群落多样性特征与永质的相互关系,其中PFU原生动物1天的群集速度(功能参数)较好地反映了5个采样站(1个设在较干净水体温榆河作为对照站)水质的变化趋势,各站原生物群落的结构参数(种类组成,个体丰度,生物量和多样性指数)的差异同样与水质关系密切,通过与80年代中期作者利用PFU原生动物监测通惠河污染现状和自净效能的研究资料进行了比较,表明该河流水质目前得到明显的改善。  相似文献   

2.
本文报道了1993年5月、7月和10月在府河-白洋淀六个采样站浮游动物生态学特征及其与水质相互关系的调查研究结果。利用浮游动物群落结构的综合指标(种类组成差异,种类数目变化,个体数量变动,生物量分布,多样性指数d值的增减)和功能参数(PFU原生动物的群集速度)评价了府河-白洋淀水体的污染程度和自净效能。按照Margalef多样性指数d值的变化范围,把府河-白洋淀六个采样站的水质划分成不同的次序和等级。文中就如何控制污染,提高府河的自净效果,改善白洋淀的水质提出了具体措施和建议.  相似文献   

3.
白洋淀原生动物群落多样性变化与水质关系研究   总被引:40,自引:6,他引:34  
许木启  朱江  曹宏 《生态学报》2001,21(7):1114-1120
报道了大型浅水型湖泊原生动物群落变化与富营养化关系的研究,通过对华北平原最大淡水湖-河北白洋淀两个湖区9个采样站的初步调查,共鉴定出77种原生动物,其中43种为该湖首次记录:利用PFU原生动物群落结构和功能方法快速(两次实验的群集速度均为1d时间)监测了不同湖区的水质状况,水质分析及原生动物定性和定量调查结果表明,湖区Ⅰ(安州至枣林庄5个采样点)水体的污染程度明显大于湖区Ⅱ(圈头至端村4个采样站),通过与20世纪50年代的调查资料比较,较好地反映了白洋淀富营养化的发展趋势。  相似文献   

4.
张利永  颜天  韩刚  周名江 《生态学报》2007,27(5):1926-1936
2005年在长江口赤潮频发海域调查期间,分别于4月27日、5月4日和5月8日,在zzf1、zc18a和ra5站位利用现场船基培养的方法,研究了添加到赤潮密度10^6cells L^-1的东海原甲藻(Prorocentrum donghaiense)对原生动物群落结构的影响。结果发现,赤潮密度的东海原甲藻抑制了小型无壳纤毛虫的种群数量,而没有抑制中大型砂壳纤毛虫和夜光虫(Noctiluca scintillans)的种群数量,从而使得原生动物群落向中大型种类演替,这种影响的程度与原生动物本身的群落组成和浮游植物的组成密切相关。添加东海原甲藻72h后,在以小型无壳纤毛虫管游虫(Cyrtostrombidium sp.)为优势种的zzf1站位,演替为以大型原生动物夜光虫为优势种的群落;在以中大型原生动物百乐拟铃虫(Tintinnospsis beroidea)和夜光虫为优势种的zc18a站位,仍然是以此为优势种,且大型原生动物夜光虫在群落中的比例上升;在以小型无壳纤毛虫急游虫2(Strombidium sp.2)为优势种的ra5站位,演替为以中大型原生动物百乐拟铃虫和亚速岛网纹虫(Favella azorica)为优势种的群落。zzf1和ra5站位实验组中原生动物的总丰度都呈下降趋势,而zc18a站位变化不明显,这是由于前两个站位的最优势种管游虫(zzf1站位)和急游虫2(ra5站位)的丰度迅速下降,而zc18a站位的优势种百乐拟铃虫和夜光虫的丰度比较稳定造成的。在zzf1和zc18a站位,对照组和实验组中原生动物的总生物量在实验前后都没有大的变化,而在ra5站位却均呈下降的趋势。这可能与浮游植物的组成有关,zzf1和zc18a站位是以无毒的锥状斯氏藻(Scrippsiella trochoidea)和螺旋环沟藻(Gyrodinium spirale)为主,而ra5站位是以有毒的亚历山大藻(Alexandriumsp.)为主。综上可见,可预测当东海大规模赤潮爆发时,会使原生动物群落向中大型种类演替,进而可能影响海洋生态系统的结构和功能。  相似文献   

5.
哈尔滨人工湖泊中原生动物群落变化规律   总被引:9,自引:2,他引:7  
谭晓丽  施心路  刘桂杰  白昕 《生态学报》2005,25(10):2650-2657
2003年3月~2004年2月调查了哈尔滨人工湖泊原生动物群落多样性的变化规律,应用PFU法研究了原生动物群落季节变化演替的特征。共观察到各类原生动物120种,其中鞭毛虫53种,占原生动物总数的44%,肉足虫9种占原生动物总数的8%,纤毛虫58种占原生动物总数的48%,分析了原生动物在该湖的组成特点。原生动物在此人工湖泊中1个周年内的表现规律为植物性鞭毛虫多,动物性鞭毛虫少;纤毛虫多,肉足虫少。原生动物群落的结构参数(种类组成、个体丰度和多样性指数)因水质的变化而发生变化。在此湖中原生动物的优势种为喇叭虫属(S tentor)、眼虫属(E ug lena)、游仆虫属(E up lote)、隐滴虫属(C ryp tom onas),常年的居留种为眼虫属(E ug lena)、弹跳虫属(H a lteria)、侠盗虫属(S trobilid ium)、隐滴虫属(C ryp tom onas)。全年3个采样站的生物多样性指数在1.912~7.473之间。原生动物在1个周年中平均个体丰度出现的规律依次递减的顺序是秋季、夏季、春季、冬季。采样站1的平均个体丰度在四个季节中均高于采样站2、3。  相似文献   

6.
张利永  颜天  韩刚  周名江 《生态学报》2007,27(5):1926-1936
2005年在长江口赤潮频发海域调查期间,分别于4月27日、5月4日和5月8日,在zzf1、zc18a和ra5站位利用现场船基培养的方法,研究了添加到赤潮密度106 cells L-1的东海原甲藻(Prorocentrum donghaiense)对原生动物群落结构的影响。结果发现,赤潮密度的东海原甲藻抑制了小型无壳纤毛虫的种群数量,而没有抑制中大型砂壳纤毛虫和夜光虫(Noctiluca scintillans)的种群数量,从而使得原生动物群落向中大型种类演替,这种影响的程度与原生动物本身的群落组成和浮游植物的组成密切相关。添加东海原甲藻72 h后,在以小型无壳纤毛虫管游虫(Cyrtostrombidium sp.)为优势种的zzf1站位,演替为以大型原生动物夜光虫为优势种的群落;在以中大型原生动物百乐拟铃虫(Tintinnospsis beroidea)和夜光虫为优势种的zc18a站位,仍然是以此为优势种,且大型原生动物夜光虫在群落中的比例上升;在以小型无壳纤毛虫急游虫2(Strombidium sp.2)为优势种的ra5站位,演替为以中大型原生动物百乐拟铃虫和亚速岛网纹虫(Favella azorica)为优势种的群落。zzf1和ra5站位实验组中原生动物的总丰度都呈下降趋势,而zc18a站位变化不明显,这是由于前两个站位的最优势种管游虫(zzf1站位)和急游虫2(ra5站位)的丰度迅速下降,而zc18a站位的优势种百乐拟铃虫和夜光虫的丰度比较稳定造成的。在zzf1和zc18a站位,对照组和实验组中原生动物的总生物量在实验前后都没有大的变化,而在ra5站位却均呈下降的趋势。这可能与浮游植物的组成有关,zzf1和zc18a站位是以无毒的锥状斯氏藻(Scrippsiella trochoidea)和螺旋环沟藻(Gyrodinium spirale)为主,而ra5站位是以有毒的亚历山大藻(Alexandrium sp.)为主。综上可见,可预测当东海大规模赤潮爆发时,会使原生动物群落向中大型种类演替,进而可能影响海洋生态系统的结构和功能。  相似文献   

7.
用PFU原生动物群落进行生物监测的研究   总被引:9,自引:3,他引:6  
应用PFU法收集微型生物群落,监测鸭儿湖的农药污染。原生动物对五个氧化塘内农药废水的毒性反应,可用群集过程来表示,无论室内或是野外试验,结果基本一致。其中微型生物群落的结构参数有原生动物种类组成和种数、叶绿素a含量、水细菌数量;功能参数有反映原生动物群集过程中的Scq、G、t90%和微型生物的呼吸速度。功能和结构的参数均能较准确地反映出氧化塘系统的净化过程。PFU法可应用于预报污染物的生物效应浓度,初认为是一种经济、快速、正确的生物学监测方法。  相似文献   

8.
用PFU原生动物群落进行生物监测的研究   总被引:11,自引:1,他引:10  
应用PFU法收集微型生物群落,监测鸭儿湖的农药污染。原生动物对五个氧化塘内农药废水的毒性反应,可用群集过程来表示,无论室内或是野外试验,结果基本一致。其中微型生物群落的结构参数有原生动物种类组成和种数、叶绿素a含量、水细菌数量;功能参数有反映原生动物群集过程中的S_(eq)、G、t_(90%)和微型生物的呼吸速度。功能和结构的参数均能较准确地反映出氧化塘系统的净化过程。PFU法可应用于预报污染物的生物效应浓度,初认为是一种经济、快速、正确的生物学监测方法。  相似文献   

9.
在对虾养殖池塘水体中共检测到原生动物86种,其中纤毛虫48种;鞭毛虫25种,肉足虫13种.原生动物优势种主要由一些运动能力相对较弱或固着生长的种类组成,如褐砂壳虫(Difflugia avellana)、瓜形膜袋虫(Cyclidium citrullus)、透明鞘居虫(Vaginicola crystalline)、多态喇叭虫(Stentor polymorphrus)和钟虫(Vorticella sp.)等,这些原生动物有以腐质和藻类为食、耐污性较强的特点.结果表明:在养殖初期,使用底质修复技术的试验池塘原生动物群落结构恢复比对照塘快,PFU群集的原生动物种类数和密度比对照塘多,水质比对照塘好,嗜污性相对较强的一些纤毛虫如尾草履虫(Paramecium caudaium)、拟瘦尾虫(Paruroleptus spp.)等比对照塘出现晚.在随后的养殖过程中,使用底质修复技术的试验塘原生动物群落结构比对照塘稳定,原生动物种类数和密度起伏小,pH值、透明度变化幅度也小于对照池塘,没有发生病害,水质较对照塘好.  相似文献   

10.
2005年4月-2006年3月调查了杭州市郊下沙区一个沼泽性水域原生动物群落的变化规律。共观察到各类原生动物265种,其中鞭毛虫114种,占原生动物总数的43%,其中植物性鞭毛虫占91%,动物性鞭毛虫仅占9%;肉足虫34种,占原生动物总数的13%,纤毛虫117种,占原生动物总数的44%。原生动物在此水域1个周年内的分布特征表现为植物性鞭毛虫种类多于动物性鞭毛虫,纤毛虫种类多于肉足虫种类。原生动物群落的结构参数(种类组成、个体丰度和多样性指数)因水质的变化而变化。此水域原生动物的优势种为梨形扁裸藻(Phacus pyrum)、旋转囊裸藻(Trachelomonas volvocina)、绿色裸藻(Euglenaviridis)和刺鱼状裸藻(Euglena gasterosteus),常年居留种为裸藻(Euglenasp.)、奇形扁裸藻(Phacus anomalus)、钟形虫(Vorticellasp.)、尾草履虫(Paramecium caudatum)和多态喇叭虫(Stentor polymorphrus)。全年3个采样站的Margalef生物多样性指数为1.056~6.054。  相似文献   

11.
不同类型虾池的理化因子及浮游植物群落的调查   总被引:10,自引:1,他引:9  
于2001年10月和2002年4月两次调查分析了高位池、低位池两种类型的南美白对虾养殖池的理化因子及浮游植物群落的特征.结果表明:低位池的营养盐浓度普遍高于高位池,而高位虾池的盐度则高于低位.盐度是影响两类虾池浮游植物群落特征的主要因素.盐度较小(<5)的养殖池中,蓝藻占优势,主要为微囊藻、平裂藻、水花束丝藻、色球藻等;盐度介于10~30的池中,硅藻占优势,主要为舟形藻、桥弯藻等.  相似文献   

12.
R. A. Newman 《Oecologia》1987,71(2):301-307
Summary The effects of density on growth and development of Scaphiopus couchi tadpoles in desert ponds were investigated, and sources of mortality over a three-year period were documented. In 16 of the 82 ponds monitored, predation was the principal cause of death, demonstrating that tadpoles in desert ponds may be exposed to high levels of predation, although the overall importance of predation is less here than in more mesic areas. Desiccation was the primary cause of mortality in 49 ponds. Growth and development were extremely slow in most high density ponds and as a result most tadpoles were unable to metamorphose before ponds dried. Only 8 ponds produced metamorphs, and mortality was high even in these. Food-supplementation resulted in some metamorphosis in high density ponds, although the effect was diminished by the extreme crowding in most ponds. In low density ponds, S. couchi tadpoles can develop very quickly and metamorphose. High mortality due to desiccation is largely a consequence of high density: tadpoles rarely completed development in high density ponds, regardless of pond duration.  相似文献   

13.
Ponds support a rich biodiversity because the heterogeneity of individual ponds creates, at the landscape scale, a diversity of habitats for wildlife. The distribution of pond animals and plants will be influenced by both the local conditions within a pond and the spatial distribution of ponds across the landscape. Separating out the local from the spatial is difficult because the two are often linked. Pond snails are likely to be affected by both local conditions, e.g. water hardness, and spatial patterns, e.g. distance between ponds, but studies of snail communities struggle distinguishing between the two. In this study, communities of snails were recorded from 52 ponds in a biogeographically coherent landscape in north-east England. The distribution of snail communities was compared to local environments characterised by the macrophyte communities within each pond and to the spatial pattern of ponds throughout the landscape. Mantel tests were used to partial out the local versus the landscape respective influences. Snail communities became more similar in ponds that were closer together and in ponds with similar macrophyte communities as both the local and the landscape scale were important for this group of animals. Data were collected from several types of ponds, including those created on nature reserves specifically for wildlife, old field ponds (at least 150 years old) primarily created for watering livestock and subsidence ponds outside protected areas or amongst coastal dunes. No one pond type supported all the species. Larger, deeper ponds on nature reserves had the highest numbers of species within individual ponds but shallow, temporary sites on farm land supported a distinct temporary water fauna. The conservation of pond snails in this region requires a diversity of pond types rather than one idealised type and ponds scattered throughout the area at a variety of sites, not just concentrated on nature reserves. Handling editor: B. Oertli  相似文献   

14.
Lentic community structure varies across a size gradient of ponds and lakes with physical factors, such as pond drying, and biotic factors, such as fish predation, determining the species assemblage. We studied the effects of pond drying and fish absence on crustacean zooplankton across a gradient of pond sizes in a Texas grassland. We determined the species compositions and size distributions of crustacean zooplankton in 20 temporary and 18 permanent ponds in April after March rains had refilled the ponds. The surface areas of temporary and permanent ponds ranged from <0.01 to 0.21 ha and 0.04 to 13.8 ha, respectively, and temporary ponds were significantly smaller, on average, than permanent ponds. Fish were absent from all temporary ponds and present in all permanent ponds. We detected a difference in the zooplankton species assemblages of the temporary and permanent ponds. Out of 14 total zooplankton taxa that occurred in eight or more ponds, seven taxa were significantly more prevalent in temporary ponds and four taxa were significantly more prevalent in permanent ponds. The sizes of zooplankton in the temporary fishless ponds were greater than those in the permanent ponds with fish present. We concluded that pond size mediated susceptibility to pond drying, and pond drying determined the presence and absence of fish and their secondary trophic-level effect on zooplankton community structure. Handling editor: Steven Declerck  相似文献   

15.
We assessed the importance for biodiversity of man-made farm ponds in an agricultural landscape in SW France lacking natural wetlands. The ponds were originally created to provide a variety of societal services (irrigation, visual amenity, water for cattle, etc.). We also assessed the environmental factors influencing invertebrate assemblages in these ponds. Only 18 invertebrate taxa out of 114 taxa occurring in the study area were common to ponds and rivers indicating that the contribution of farm ponds to freshwater biodiversity was potentially high. A Self-Organizing Map (SOM, neural network) was used to classify 36 farm ponds in terms of the 52 invertebrate families and genera they supported, and to specify the influence of environmental variables related to land-use and to pond characteristics on the assemblage patterns. The SOM trained with taxa occurrences showed five clusters of ponds, most taxa occurring only in 1–2 clusters of ponds. Abandoned ponds tended to support higher numbers of taxa, probably because they were allowed to undergo a natural succession. Nevertheless, abandoned ponds were also amongst the largest, so that it remained difficult to separate the effects of pond size and abandonment, although both factors were likely to interact to favour higher taxon richness. The invertebrate communities in the ponds appeared to be influenced mainly by widely acting environmental factors (e.g. area, regionalization of assemblages) with little evidence that pond use (e.g. cattle watering, amenity) generally influenced assemblage composition. Our results support the idea that agricultural landscapes containing man-made ponds make a significant contribution to freshwater biodiversity indicating that protection of farm ponds from threats such as in-filling and pollution can make a positive contribution to the maintenance of aquatic biodiversity. This added value for biodiversity should be considered when calculating the economic costs and benefits of constructing water bodies for human activities. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. Guest editors: R. Céréghino, J. Biggs, B. Oertli & S. Declerck The ecology of European ponds: defining the characteristics of a neglected freshwater habitat  相似文献   

16.
We quantitatively studied the effect of submerged plants on water quality and biota under fish-free conditions for 3 weeks in four large freshwater experimental ponds (533 m3 per pond) at the Aqua Restoration Research Center, Japan. Two artificially harvested ponds with scant vegetation were used as “harvested ponds” (H1, H2), and the other two ponds, which were naturally dominated by Hydrilla verticillata, were used as “vegetated ponds” (V1, V2). The PVI (percent water volume infested with macrophytes) was employed as an index of vegetation abundance. Vegetated ponds had much clearer water than harvested ponds. The water quality in H2 (PVI 10%) was better than in H1 (PVI 3%), whereas the water quality did not differ significantly between the two vegetated ponds (V1, PVI 38% and V2, PVI 84%). Therefore, the threshold between clear water and turbidity was between 10 and 38% in PVI. Our result also showed that a turbid water state was created shortly after harvest. Green algae were abundant in the harvested ponds, and diatoms were dominant in the vegetated ponds. Rotifers were stably dominant in the harvested ponds. Aquatic worms were more abundant in the harvested ponds than in the vegetated ponds. Unexpectedly, zooplanktons were much less abundant in the vegetated ponds; therefore, zooplankton grazing was not the main mechanism behind the cleaner water in our experiment. These results are physical evidence that the presence of dense macrophytes was the main factor in the creation of a clear water state.  相似文献   

17.
The use of water hyacinth compost as manure in nursery ponds for larval rearing of Indian major carp, Labeo rohita was studied. Better performance with regard to growth and survivability of the larvae was recorded in the ponds treated with water hyacinth compost (Group A) than in either the ponds treated with inorganic fertilizers (Group B) or the ponds where no treatment was applied (Group C). The average percentages of survival in Groups A, B and C were 14.3, 11.2 and 5.0, respectively. Thus about 186% increase in the survivability was recorded in the ponds treated with water hyacinth compost (P < 0.01), whereas the increase was about 124% in the ponds treated with only inorganic fertilizers, when compared with the ponds which were without any treatment.  相似文献   

18.
Patterns in benthic food webs: a role for omnivorous crayfish?   总被引:10,自引:0,他引:10  
1. The biomass and species richness of macrophytes and invertebrates in artificial ponds at two sites in southern Sweden (twenty-one ponds at each site) were investigated. Alkalinity was high at one site (H ponds) and low at the other site (L ponds). The ponds chosen had different densities of signal crayfish (Pacifastacus leniusculus), with mean crayfish abundance (estimated by trapping and expressed as catch per unit effort) significantly higher in the L ponds (10.7) than in the H ponds (4.9). Macrophytes, invertebrates, the amount of periphyton on stones and the organic content of the sediment were determined in each pond. 2. Macrophyte biomass, cover and species richness declined with increasing crayfish density. Macrophyte species composition differed between ponds and was related to crayfish abundance. 3. The total biomass of invertebrates and the biomass of herbivorous/detritivorous invertebrates declined with increasing crayfish abundance, but the biomass of predatory invertebrates declined only in the L ponds. The relative biomass of Gastropoda and Odonata declined in ponds where crayfish were abundant. In ponds where crayfish were abundant the invertebrate fauna was dominated by sediment-dwelling taxa (Sialis (H and L ponds) and Chironomidae (H ponds)). 4. The number of invertebrate taxa in macrophytes declined with increasing crayfish abundance. The percentage of macrophyte-associated invertebrate taxa differed between ponds, but also between sites. The relative biomass of Gastropoda declined in H ponds where crayfish were abundant. In H ponds Trichoptera or Gammarus sp. and Heteroptera dominated where crayfish were abundant, whereas Odonata dominated in L ponds with abundant crayfish. 5. The organic content of the sediment decreased in ponds with high crayfish densities, while the amount of periphyton on stones was not related to crayfish density. 6. We conclude that the signal crayfish may play an important role as a keystone consumer in pond ecosystems, but lower trophic levels did not respond to changes in the abundance of the crayfish according to the trophic cascade model. Omnivorous crayfish may decouple the cascading effect.  相似文献   

19.
Despite the presence of high nutrient concentrations, most ponds located around Brussels (Belgium) show a considerable variation in turbidity. The importance of submerged macrophytes in maintaining the clear-water state requires identification of the main factors determining macrophyte abundance and diversity in ponds and small lakes. In this study, the inter-relationships between submerged macrophyte cover, fish abundance and turbidity were investigated in 13 eutrophic peri-urban ponds. Along a turbidity gradient, vegetation switched from dominance by Stoneworts (Chara and Nitella spp.) in the clearest ponds, to dominance by Potamogeton pectinatus in ponds with a slightly lower water transparency. Despite the presence of both P. pectinatus and Stoneworts in each of the vegetated ponds, only one became dominant. Only a very low abundance (around 20%) of submerged vegetation was found in ponds of intermediate turbidity, while macrophytes were absent in turbid ponds. Multi- and univariate analysis showed a marked difference in chemical, physical and biological properties between ponds deliberately used for fish stocking and ponds that were not. Macrophyte cover was significantly negatively correlated with turbidity and plankti-benthivorous fish abundance. No such correlation was observed with piscivorous fish abundance, except for pike that were associated with a charophyte vegetation in the study ponds. The strong relationship found between fish abundance and turbidity, its negative effect on submerged vegetation cover, and the importance of submerged vegetation in controlling phytoplankton abundance, should be taken into account when selecting ponds for fish stocking. It also suggests that the study ponds have a good potential for ecological quality restoration by biomanipulation.  相似文献   

20.
珠三角高产养殖池塘浮游动物群落结构及水质评价   总被引:1,自引:0,他引:1  
为进一步了解珠三角高产池塘养殖环境状况, 分析珠三角高产池塘浮游动物群落特征及与池塘水质的相关性, 研究于2016年7—8月对珠三角地区6种主要高产养殖模式30口池塘的浮游动物和环境因子进行了调查。研究结果表明: (1)共采集浮游动物55种, 其中原生动物17种、轮虫29种、枝角类4种、桡足类5种。6种养殖模式池塘中, 大口黑鲈S池塘浮游动物种类数最多, 为34种; 草鱼池塘最少, 为18种。(2)30口池塘共记录优势种8种, 其中原生动物和轮虫各4种, 枝角类和桡足类均不占优势。在6种养殖模式池塘中, 优势种也仅包括原生动物和轮虫, 优势种种类数变化范围为5—8种。(3)30口池塘浮游动物平均密度和生物量均较高, 分别为21354 ind./L和9.36 mg/L。方差分析结果表明6种养殖模式池塘浮游动物密度和生物量均不存在显著差异。(4)RDA分析结果表明, TP和pH是影响珠三角池塘浮游动物分布的主要因素。采用浮游动物丰度和生物量对水质的评价结果显示, 6种养殖模式池塘均处于富营养化状态; 运用Shannon-Wiener多样性指数和Margalef多样性指数对水质的评价结果表明, 6种模式养殖池塘均处于α-中污状态, 且以草鱼池塘的污染最为严重。本研究首次利用浮游动物对珠三角高产池塘进行水质评价, 研究结果可为池塘生态修复和管理提供一定的指导意见。  相似文献   

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