Spatial changes in zooplankton communities in a strong ... › articles › 5087.pdf · communis, Sparganiun erectum), whereas the central zone of the bed impoundment was covered

Submitted 24 March 2018Accepted 5 June 2018Published 3 July 2018

Corresponding authorMonika Kowalska-Goacuteralskamonikakowalska-goralskaupwredupl

Academic editorJoumlrg Oehlmann

Additional Information andDeclarations can be found onpage 21

DOI 107717peerj5087

Copyright2018 Czerniawski and Kowalska-Goacuteralska

Distributed underCreative Commons CC-BY 40

OPEN ACCESS

Spatial changes in zooplanktoncommunities in a stronghuman-mediated river ecosystemRobert Czerniawski1 and Monika Kowalska-Goacuteralska2

1Department of General Zoology Centre of Molecular Biology and Biotechnology University of SzczecinSzczecin Poland

2 Institute of Biology Department of Hydrobiology and Aquaculture Wrocław University of Environmentaland Life Sciences Wroclaw Poland

These authors contributed equally to this work

ABSTRACTRiver damming causes a decrease in water current velocity which leads to an increasein richness and abundance of organisms atypical for running waters Zooplanktonis a representative example of such organisms The influx of zooplankton from carpponds is an additional factor that increases richness and abundance of zooplankton inrivers We hypothesized that zooplankton dispersing from the carp ponds colonize theimpoundments in river and the richness of zooplankton increase in impoundmentsby development of new species not observed in the upstream The zooplankton wascollected monthly from April to September of 2013 and 2014 Sampling sites werelocated in the Barycz river (in the lotic sections and in the dam impoundments) aswell as in its tributaries which are the outlets of carp ponds The most changes inzooplankton richness and abundance were observed at sites located within the damimpoundments especially in relation to the lower values of the current velocity Sincethe abundance of pelagic rotifers cladocerans and copepods in the carp pondoutletswassimilar to that at lower sites in the Barycz the influence of the carp pond outlets on theabundance in the damand lotic sectionswas significant The river itself in its impoundedsections provides advantageous conditions for retention and colonization by a highabundance of zooplankton dispersing from the carp ponds and for the developmentof species not occurred in the upstream which in turn increases richness

Subjects Aquaculture Fisheries and Fish Science Biodiversity Ecosystem Science FreshwaterBiologyKeywords Small dams Ecohydrology Aquaculture impact Carp pond impact Biologicalindicators

INTRODUCTIONCatchment management is one of the factors that determines the functioning of a regionand comprises numerous technical measures that depend on a regionrsquos needs river-bedmaintenance agricultural drainage water impoundments for fish farming or securingenergy needs flood control systems and water retention (Jones et al 2004 Soranno etal 2015 Ullah Jiang amp Wang 2018) On the other hand there are also works such asrestoration of river stretches which intend to make the area more appealing increase itseconomic and biodiversity potential as well as the environmental value (Dufour amp Pieacutegay

How to cite this article Czerniawski and Kowalska-Goacuteralska (2018) Spatial changes in zooplankton communities in a strong human-mediated river ecosystem PeerJ 6e5087 DOI 107717peerj5087

2009 Zawal et al 2016) Consequently all the technical measures which alter the river-bedand the hydrological conditions affect the biological functioning of the lotic sections

Human-made dams are one of the most important technical measures that break theriver continuum Oftentimes they cause irreversible alterations in rivers and distort theirnatural flow (Allan amp Castillo 2007) Such alterations are reflected in physicochemical andbiological variables as well as the loss and replacement of typical lotic species by typicalstagnant water species A large number of studies examine how large dams in large riverscause changes in environmental conditions whereas few papers address the impact ofsmall dams in small rivers or streams However small dams impounding a water of upto 4 m cause similar changes in river ecosystems albeit on a much smaller scale In smallrivers even small dams can affect the flora and fauna composition by inducing rapidchanges in hydrological and physicochemical variables (Cumming 2004 Wu et al 2010Zhou et al 2008) Small dams create distinct physical and ecological conditions that arerelatively different from the ones found in free-flowing lotic sections This is manifested bya reduction of current velocity increase of water retention time and increase of nutrientcontent

These new conditions eg long water retention time and low current velocity aresuitable for the growth of zooplankton populations that in turn are a good indicatorof hydrological changes (Czerniawski amp Domagala 2014 Otrsquoahelrsquoovaacute amp Valachovič 2002Zhou et al 2008) Zooplankton can develop in stagnant waters or in slow-flowing waterswith current velocities lower than 01 m sminus1 (Czerniawski amp Domagala 2014 Zhou etal 2008) Given that zooplankton reacts rapidly to the hydrological changes caused bydams Until now the influence of dams on zooplankton communities has been studiedprimarily in large rivers with dammed water up to more than 15 m (Akopian Garnieramp Pourriot 1999 Doi et al 2008 Pourriot Rougier amp Miquelis 1997 Żurek amp Dumnicka1989) However only a few studies have investigated the influence of small dams onzooplankton communities (Czerniawski amp Domagala 2014 Zhou et al 2008) Smalldams promote the formation of biotopes of the ecotone type in which the zooplanktoncommunity develops features similar to or different from those communities in lakes andlarge reservoirs (Czerniawski amp Domagala 2014 Zhou et al 2008)

Another process leading to alterations in a man-changed environment is catchmenttransformation ie creation of retention reservoirs or fish ponds joined with mainchannel of the river The amount of dead and live organic matter (including zooplankton)significantly increases in such reservoirs (Kloskowski 2011 Meijer et al 1990 Rahman etal 2008) An example of artificial reservoirs are carp ponds which lead to the increase inorganic matter and cause an influx of the organic matter to the rivers High biomass ofcommon carp cause an increase of nutrients turbidity and suspended solids hence thesebasins have a strong influence onwater quality and aquatic community structure (Nieoczymamp Kloskowski 2014 Parkos Santucci amp Wahl 2003) The dispersion of carp-pond plankterscan enrich the river with high densities or new zooplankton species The inorganic andorganic nutrients in the water column can drift to the outlet section thereafter and thenbe dispersed into rivers

Czerniawski and Kowalska-Goacuteralska (2018) PeerJ DOI 107717peerj5087 226

None of the abovementioned studies investigated the concurrent impact of zooplanktoninflux from carp ponds and small dams impounding water of these carp ponds on thezooplankton communities in rivers Moreover in the case of the present study small riverdams can create suitable conditions for the dispersed carp-pond plankters and for thedevelopment of new zooplankton species (not present in the upstream) That is why thesum of alterations occurring in a small river and its immediate surroundings can enhancechanges in qualitative and quantitative structure of zooplankton in a different manner thandams alone This phenomenon has not been examined Therefore we decided to investigatethe concurrent impact of both factors on zooplankton communities in a small river (i)impact of the dams impounding the river water and (ii) impact of the zooplankton influxfrom the carp ponds outlets

Construction of a small dam and the zooplankton influx from the carp pond outletswould significantly shape the zooplankton community in a river environment Theoverall goal of the study was to examine the distribution of the zooplankton richnessand abundance in a river dammed in many places and connected with the carp pondsThe following tasks were proposed a comparison of the zooplankton communitiesbetween the free-flowing lotic sections and the impounded sections of the river (1) and acomparison of the zooplankton communities between the carp pond outlets and the river(2) We hypothesized that zooplankton dispersing form the carp ponds can colonize theimpoundments in river (1) and the richness of zooplankton increase in impoundments bydevelopment of new species not observed in the upstream (2)

METHODSStudy areaThis study was performed in the Barycz and its few tributaries which are outlets of carpponds (drainage of the Oder river SW Poland) (Fig 1) The Barycz is a river in the LowerSilesian Province in southwestern Poland It is a right tributary of theOder river The Baryczis 139 km long has a catchment area of 5526 km2 and is characterized by a mean slopeof 0035 The catchment of the Barycz Valley Landscape Park is an important wetlandreserve Carp ponds in the Barycz Valley are the largest carp breeding ponds in CentralEurope They constitute the biggest complex of fish ponds and the oldest group of artificialreservoirs in Poland they were built as early as the 15th and 16th century for carp farming(Gąbka Dolata amp Antonowicz 2007) The location of the ponds in the Barycz Valley allowsthe inflow of gravitational water The Barycz provides water for the carp ponds thereforenumerous dams and impoundments are located along the river Currently the total area offish ponds in the catchment of the Barycz covers approximately 7500 ha The proportion ofthe agricultural area of the Barycz in the catchment is approximately 80 From August toOctober an accelerated discharge of water from the carp ponds into the Barycz is observedIn the examined stretch of the Barycz 31 dams with a hydraulic height of 12 mndash46 m arelocated

Sampling sites were located in the Barycz in the lotic free-flowing sections (R1 R2 R3R4) at the dam impoundments (D1 D2 D3 D4 D5) and in the tributaries of the Barycz


Figure 1 Study areaFull-size DOI 107717peerj5087fig-1

which are also carp pond outlets (T1 T2 T3 T4 T5) (Fig 1) The hydraulic heights of thedams at D1 D2 D3 D4 and D5 were respectively 25 m 25 m 16 m 23 m and 16 mIn Barycz river Lagrangian scheme according to which cross-sections were sampled in adownstream sequence with the sampling interval approximating the time of travel betweensites The sampling sites of Barycz were chosen under account (1) influence of the carppond outlets (2) influence of the dam impoundments on zooplankton communities indownstream (3) easy access

Sand was the dominant component in the sediments of the lotic sections of the BaryczWhereas the sediments of the impoundments were marshy (contained leaf litter) withmany small floodplains and slackwater areas The riparian zone of the impoundments wasdensely covered by emerging macrophytes (dominants Glyceria maxima Phragmintescommunis Sparganiun erectum) whereas the central zone of the bed impoundmentwas covered by elodeids (dominants Potamogeton natans Ceratophyllum demersumPotamogeton perfoliatus Sagittaria sagittifolia) The riparian zone of the lotic sections wassporadically covered by emerging macrophytes (dominants Glyceria maxima Sparganiunerectum) whereas its central bed was sporadically covered by Potamogeton perfoliatus andSagittaria sagittifolia

Tributariesmdashoutflows of the carp pondsmdashwere regulated channels with a sandy bottomThe owners of carp ponds remove regularly aquatic vegetation from both the riparian zoneand the central part of the bed to ensure free and unobstructed water flow to the Barycz


Tributaries between the carp ponds and the Barycz did not include any slack-water areas orfloodplains Therefore the morphological conditions of the outlets were characterized by arelatively fast water current (from 036 m sminus1 to 048 m sminus1) No particular field samplingpermits with regard to the site locations eg the national park or other protected area andprotected species were needed

Sampling methodsThe zooplankton was collected monthly from April to September of 2013 and 2014 (n =12) At each site 50 L of water was collected from the river current The samples werecollected using a Van Dorn 5-liter water sampler (KC Denmark) at five depths 20 4060 80 and at the surface (Czerniawski amp Domagala 2014) At each depth level 10 Lof water was collected to obtain 50 L of water The water was filtered through a planktonnet with a mesh of 30 microm The samples were then concentrated to 150 ml and fixed in a4ndash5 formalin solution The contents of the samples were counted in a Sedgewick-Raftercounting chamber in ten 3-ml sub-samples A Nikon Eclipse 50i microscope was used foridentification Species were identified using the keys described byNogrady Wallace amp Snell(1993) and Rybak amp Błędzki (2010)

Measurements of chlorophyll a content were made in situ using the Hydrolab DS 5multiparameter probe (OTT Hydromet Loveland CO USA) At each site water velocitywidth and depth weremeasured with an electromagnetic water flow sensor OTT (KemptenGermany) to determine water discharge A cross-section of the stream channel was dividedinto five vertical subsections In each subsection the area was obtained by measuring thewidth and depth of the subsection and water velocity was determined using a currentmeter Water discharge in each subsection was calculated by multiplying the subsectionarea by the measured velocity The total discharge was then counted by summing up thedischarge values of each subsection

Data analysesRotifers were divided into two categories according to habitat preferencendashpelagic species(plankton) and benthic epiphytic epilithic species associated with the substratumotherwise known as benthic species (Radwan 2004 Zhou et al 2008) Taxonomicalsimilarity between the sites was calculated using the Sorensenrsquos index We used theKruskalndashWallis test (P lt 005) for checking the significance of differences in the chlorophylla content discharge and current velocity values and the richness (number of species) andthe abundance of each zooplankton group among the sites Post-hoc multiple comparisonsof mean ranks for all groups were conducted (P lt 005) to determine the significantdifferences in the zooplankton richness and abundance between the sites Cluster analysisbased on Euclidean distance was used to identify groups of similar sites of tributariesimpoundments and lotic sections with regard to the richness and the abundance ofzooplankton To illustrate the similarities between the sites (lotic sections R1ndashR4 vsdammed sections D1ndashD5 vs tributaries T1ndashT5) in terms of all taxa abundance nonmetricmultidimensional scaling ordination (nMDS) technique was used The grouping in thenMDS ordination was based on the BrayndashCurtis distances (Oksanen et al 2016) In order


to determine the influence of environmental factors on richness and the abundance ofzooplankton Spearmanrsquos correlation was applied (P lt 005) For the evaluation of thecorrelation between environmental factors versus the zooplankton richness and abundancein the Barycz the following factors were considered NDmdashnumber of dams above thesite in the Barycz DCPmdashdistance between the site in the Barycz and the closest carppond in the pond system NCOmdashnumber of the carp pond outlets above the site in theBarycz TPelRotRmdashrichness of pelagic rotifers in the closest tributary above a site in theBarycz TBenRotRmdashrichness of benthic rotifers in the closest tributary above a site inthe Barycz TClaRmdashrichness of cladocerans in the closest tributary above a site in theBarycz TCopRmdashrichness of copepods in the closest tributary above a site in the BaryczTPelRotAmdashabundance of pelagic rotifers in the closest tributary above the site in theBarycz TBenRotAmdashabundance of benthic rotifers in the closest tributary above the site inthe Barycz TClaAmdashabundance of cladocerans in the closest tributary above the site in theBarycz TNaupCAmdashabundance of copepods Nauplii in the closest tributary above the sitein the Barycz TCopAmdashabundance of copepods in the closest tributary above the site inthe Barycz

The environmental conditions at the tributary sites were very similar and had absolutelyno effect on the development of the zooplankton composition The zooplanktoncomposition in the tributaries (carp pond outlets) depended entirely on the conditionspresent in the carp pond upstream Hence when calculating the correlation betweenzooplankton and environmental factors the environmental conditions at the outlets werenot taken into consideration as they could alter the end results

RESULTSEnvironmental factorsThe means of the measured abiotic variables of chlorophyll a content discharge currentvelocity and values of constant factors are shown in Table 1 Generally a spatial increaseof the chlorophyll a values was observed However in the lotic sections the chlorophyll acontent decreased in relation with the dam sites Significantly lower current velocity valueswere observed at the dam sites than at the lotic section From R2 a significant increase indischarge occurred and another rapid increase in discharge was observed from D5

Taxonomic compositionA spatial increase in the number of zooplankton taxa was observed (Table 2) A highernumber of taxa was noted at the dam sites in the Barycz than in its tributaries (carp pondoutlets) (Table 2) Only at R1mdashthe first site of the Barycz (not influenced by the tributariesand the dams)mdashthe number of taxa was the lowest

All taxa observed in tributaries were also detected in the Barycz (Table 2) Howevernot all species observed in the Barycz especially the ones at dam sites occurred in samplescollected at the tributaries Among them were rotifers Scaridium longicauda Synchaetaoblonga Testudinella patina Trichocerca capucina Trichocerca similis cladoceransEurycercus glacialis Bosmina gibbera Ceriodaphnia laticaudata Disparolona rostrataGraptoleberis testudinaria Pleuroxus trigonellus Simocephalus lusaticus copepods


Table 1 Mean valuesplusmn SD of chlorophyll a content discharge and current velocity values and con-stant factors of the examined sites in the Barycz river

Site Chl a(microg lminus1)

Discharge(m3 sminus1)

Velocity(m sminus1)

ND DCP (km) NCO

R1 37plusmn 23 a 027plusmn 012 a 027plusmn 006 a 0 ndash ndashD1 83plusmn 54 ab 034plusmn 015 b 008plusmn 001 b 5 97 1R2 102plusmn 66 ab 200plusmn 087 c 023plusmn 005 a 8 15 1D2 135plusmn 78 bc 216plusmn 094 cd 006plusmn 002 b 11 03 2D3 164plusmn 92 bc 238plusmn 104 cde 006plusmn 002 b 13 01 3D4 182plusmn 89 bc 255plusmn 111 cde 005plusmn 002 b 15 01 4R3 116plusmn 69 bc 263plusmn 115 cde 016plusmn 004 a 16 73 4D5 229plusmn 103 c 427plusmn 186 de 002plusmn 002 b 23 69 5R4 147plusmn 66 bc 577plusmn 251 e 039plusmn 009 a 31 36 5

NotesChl a chlorophyll a content velocity current velocity ND number of dams above the site in the Barycz river DCP dis-tance between the site in the Barycz river and the closest carp pond in the pond system NCO number of carp pond outlets(T) above the site in the Barycz riverLetters in column show significant differences between the sitesR1ndash3 sites in the free-flowing waters of the Barycz river D1ndash5 sites in the dams of the Barycz river T1ndash5 sites in the tribu-taries of the Barycz river

Mesocyclops gigas The frequency (number of samples in which a species occurred inrelation to number of all samples expressed as a percentage) of different taxa was higher atthe Barycz sites than in the tributaries eg Brachionus sp Cephalodella apocolea Euchlanisdilatata Mytilina sp Alona sp Eucyslops macruroides Eudiaptopus gracilis (Table 2)

Sorensenrsquos similarityThe Sorensen taxonomic similarity index value between the tributaries and the sites belowthem in the Barycz was more than 60 (Fig 2) The farther the distance from the tributaryto the Barycz sites the lower the Sorensen similarity index value Taxonomic similaritybetween the subsequent sites of the Barycz was relatively high (more than 60) Thehighest similarity (more than 90) was observed between the last sites in the BaryczmdashD5and R4

Richness of zooplanktonIn the case of pelagic rotifers the higher the mean richness in the tributaries the highervalues of this parameter were observed at the subsequent sites below a tributary in theBarycz (Fig 3) However no significant differences in richness of pelagic rotifers occurredbetween these sites (P gt 005) The mean richness of pelagic rotifers in R1 was significantlylower than in each tributary (P lt 005) apart from T1 (P gt 005) (Table 3) The meanrichness of benthic rotifers was similar at each site and did not differ significantly betweenthe sites in the tributaries dams and lotic sections of the Barycz (P gt 005) (Table 3)

In the case of cladocerans mean richness differed significantly from most sites inthe Barycz and its tributaries only at R1 (P lt 005) (Table 3) where the mean richnesswas lower than compared with the other sites The mean richness of copepods differedsignificantly only between R1 and T2 Contrary to pelagic rotifers crustaceans (cladoceransand copepods) were characterized by a slightly higher mean richness at the dam sites than


Table 2 Taxonomical composition and frequency of total zooplankton at each site of the Barycz River and its tributaries R1ndash4 sites on free-flowing stretch of the Barycz D1ndash5 sites on the dams T1ndash5 sites on the tributaries Values in table are related to frequency

Taxa R1 T1 D1 R2 T2 D2 T3 D3 T4 D4 R3 T5 D5 R4

Ascomorpha saltans 14 14 14 14Asplanchna priodonta 14 14 14 43 43 14 14 43 71 43 29Bdelloidea 36 100 86 86 100 57 57 71 86 64 71 86 64 64Brachionus angularis 14 14 14 14 21 14 14 36 29 14Brachionus calicyflorus 29 29 43 43 29 29 29 29 29 29 21Brachionus diversicornis 29 29 29 14 14 29 14Brachionus falcatus 14 14 29 14Brachionus leydigii 14 14Brachionus quadridentatus 14 14 7 14 29 14 14 7 14Bracionus rubens 14 14 14 14 14Brachionus urceoralis 7 14 14 14 14 14Cephalodella apocolea 21 21 14 21 7 14 7Colurella adriatica 14 14 7 7Euchlanis dilatata 7 21 7 7 14 7 29Filinia longiseta 14 14 43 14 57 14 43 21 43 14 14Kellicottia longispina 7 14 14 57 14 57 14 14Keratella cochlearis 21 100 71 14 100 43 86 29 100 29 71 100 57 71Keratella quadrata 14 71 36 43 71 43 100 29 86 29 50 86 57 64Lecane clocterocerca 14 14 29 14Lepadella acuminata 7 14 14Lepadella ovalis 14 29 14Mytilina crassipes 14 14 14 14 14Mytilina mucronata 14 14 21 29 29 43 43 29 36 36 29 21 57Platyias quadricornis 14 14 14 21 29 14Polyarthra longiremis 14 14 14 14Polyarthra vulgaris 14 14 14 29 14 29 57 14 14Scardinium longicaudatum 14Synchaeta pectinata 14 14 14 14Synchaeta oblonga 14Testudinella patina 7 7 7 7 14 14 7Trichocerca capucina 14Trichocerca similis 7 14 14 14 14 14Trichotria pocillum 14 14Acropeus harpae 7 14 14 29 14 14 14Alona costata 7 14 14 14Alona guttata 29 14 14 14 14Alona quadrangularis 14 14 21Alona rectangula 14 14 14 14 29 14 29 14 14 7Alonella nana 14 14 29 14 29 14 21 29Eubosmina coregoni 14 14 14 43 14 14 14 14 14 14 7Eubosmina longicornis 7 21 7 14 14 29 21 29 43 29 7

(continued on next page)


Table 2 (continued)


Eurycercus glacialis 14 14Bosmina gibbera 14Bosmina longirostris 14 71 50 43 86 71 86 43 100 71 57 86 64 86Ceriodaphnia quadrangula 14 14 43 29 43 43 43 29 43 43 14 7Ceriodaphnia laticaudata 14 14Chydorus ovalis 29 29 14 29 29 29 29 29 29 7Chydorus sphaericus 21 93 64 50 71 64 100 50 100 43 50 79 71 79Daphnia cucullata 14 29 29 29 7 29 14 29 14Daphnia longispina 29 14 14 14 57 29 7Diaphanosoma brachyurum 14 14 14 14Disparolona rostrata 14Graptoleberis testudinaria 14 29Peracantha truncata 14 14Pleuroxus trigonellus 14 14 14Scapholeberis mucronata 14 29 14 14 14 14 14 14Simocephalus lusaticus 14 7Simocephalus serrulatus 14 14 14 14 14 10 14 14 14Simocephalus vetulus 14 14 14 14Nauplii Cyclopoida 79 100 79 79 100 93 100 79 93 79 86 100 93 100Copepodit Cyclopoida 21 86 43 71 100 79 100 86 100 64 71 100 57 57Acanthocyclops robustus 7 71 43 29 79 64 71 43 36 29 29 50 29 29Eucyclops macruroides 7 14 14 21 36 21 29 29 29 7Eucyclops serrulatus 14 14 14 14 7 7 7Eudiaptomus gracilis 7 7 21 14 14 7Megacyclops gigas 14 7 14 14Taxa number 20 27 25 27 25 34 35 42 35 44 33 31 40 34

Notesbold gt 20 italic-bold 10ndash20 italic gt 5 of the mean total abundance of zooplankton at the site of each stream taxa that were lesser than 5 of the mean total abundanceare not marked

in the tributaries (P gt 005) In the lotic sections of the Barycz no significant decreasein the richness in relation with the impoundments was observed Therefore the meanrichness of crustaceans was similar between the Barycz (the dam and the lotic section sites)and its tributaries

The richness similarity dendrogram of cluster analysis shows that the tributary sites arerather separated from other sites with respect to pelagic rotifers cladocerans and copepods(Fig 4) The richness of these groups at the first lotic section sites is farther from the lastsites in the impoundments The dendrogram does not show such differences in the richnessof benthic rotifers

Abundance of zooplanktonPelagic rotifers contributed to the increase in zooplankton abundance in the Barycz belowthe tributaries or dams (Fig 5) However no significant differences in the abundance ofpelagic rotifers occurred between these sites (P gt 005) (Table 4) The mean abundance ofpelagic rotifers at R1 was significantly lower than at the tributary sites (P lt 005)


Figure 2 Sorensenrsquos similarity index value between the free-flowing (lotic) sites of the Barycz river (R)the dam sites of the Barycz (D) and the tributaries of the Barycz (T)

Full-size DOI 107717peerj5087fig-2

Table 3 All significant differences (P-values) between the studied sites for the richness of the zoo-plankton groups (post-hoc multiple comparisons of mean ranks for all groups)

Group Site T1 T2 D2 T3 T4 R3 T5 D5 R4

Pelagic Rotifera R1

D1

R2

D2

D3

D4

Cladocera R1

Copepoda R1

NotesP lt 005P lt 001P lt 0001

The mean abundance of benthic rotifers did not differ significantly between the sites(P gt 005) (Table 4) Generally with respect to the subsequent sites a higher abundanceof benthic rotifers occurred in the Barycz (dam and lotic sections) than in the tributaries(Fig 5)

Similarly to pelagic rotifers cladocerans and copepods (Nauplii and the remainingstages) demonstrated a increase in the mean abundance in the Barycz below the tributaries(Fig 5) However contrary to the richness values the abundance of crustaceans in the dam


Figure 3 Spatial distribution of the zooplankton richness in the Barycz river R1ndash4 sites in the free-flowing waters of the Barycz D1ndash5 sites in the dams of Barycz T1ndash5 sites in the tributaries of the Barycz(A) Pelagic Rotifera (B) Benthic Rotifera (C) Cladocera (D) Copepoda



Figure 4 Dendrogram (cluster analysis) of the sites in the Barycz river R1ndash4 sites in the free-flowingwaters of the Barycz river D1ndash5 sites in the dams of the Barycz river T1ndash5 sites in the tributaries of theBarycz river based on the richness of pelagic rotifers benthic rotifers cladocerans and copepods (A)Pelagic Rotifera (B) Benthic Rotifera (C) Cladocera (D) Copepoda


Table 4 All significant differences (P-values) between the studied sites for the abundance of the zoo-plankton groups (post-hoc multiple comparisons of mean ranks for all groups)

Group Site T1 D1 R2 T2 D2 T3 T4 T5 R4

Pelagic Rotifera R1

Cladocera R1

T2

Nauplii R1

T2

Copepoda R1

T2

T3


sites was lower than in the tributaries and higher than in the lotic sections The abundanceof cladocerans at R1 was significantly lower than at the tributary sites and D2 (P lt 005)(Table 4) Copepods (all stages) obtained the lowest abundance at R1 The abundance ofNauplii at R1 was significantly lower than at T2 T3 and T5 While the abundance of other


Figure 5 Spatial distribution of the zooplankton abundance in the Barycz river R1ndash4 sites in the free-flowing waters of the Barycz D1ndash5 sites in the dams of Barycz T1ndash5 sites in the tributaries of the Barycz(A) Pelagic Rotifera (B) Benthic Rotifera (C) Cladocera (D) Naupli (E) Copepoda



Figure 6 Dendrogram (cluster analysis) of the sites in the Barycz river R1ndash4 sites in the free-flowingwaters of the Barycz D1ndash5 sites in the dams of the Barycz T1ndash5 sites in the tributaries of the Baryczbased on the abundance of pelagic rotifers benthic rotifers cladocerans Nauplii and copepods (A)Pelagic Rotifera (B) Benthic Rotifera (C) Cladocera (D) Naupli (E) Copepoda


copepods stages at R1 was significantly lower than at the sites of the tributaries (P lt 005)Considering the subsequent sites below the tributaries there were no significant differencesin the abundance of crustacean groups between the sites (P gt 005)

Based on the abundance of pelagic rotifers cladocerans copepods (Nauplii and theremaining stages) the cluster analysis shows a spatial similarity between the tributaries andthe Barycz sites (Fig 6) Such similarity is not observed when it comes to the abundance ofbenthic rotifers


Figure 7 nMDS ordination for the abundance of all taxa at sites in the Barycz system The grouping inthe nMDS ordination was based on the BrayndashCurtis distances Sites white lotic sections of the river greydammed sections of the river black tributaries (carp pond outlets) White triangle R1 white square R2white circle R3 white rhombus R4 grey triangle D1 grey square D2 grey circle D3 grey rhombus D4grey cross (X) D5 black triangle T1 black square T2 black circle T3 black rhombus T4 black cross(X) T5


The nMDS ordination showed a high similarity between the tributary sites The damsites exhibit less similarity and the lotic section sites showed the smallest similarity (Fig 7)The nMDS ordination also indicated the greatest similarity in the zooplankton abundanceoccurred between the tributary sites and the dammed sites and not between the tributarysites and the lotic section sites The analysis showed also a similarity between subsequentsites (generally the distances between subsequent sites of tributary dam and lotic sectionwere the smallest)

At all sites crustaceans were abundance dominants (Fig 8) Between the tributaries andthe sites at the dam or lotic sections located below a similar percentage of the same groupscomprised of the total zooplankton abundance (Fig 8) At the lotic section sites (in relationwith the dam upstream) a decrease in the percentage of abundance of cladocerans andcopepods was observed The same species were abundance dominants at the carp pondoutlets (tributaries) and below their mouths in the Barycz (in the impoundments and loticsections) This pattern was best manifested by Bosmina longirostris Chydorus sphaericusNauplii Cyclopoida and Acanthocyclops robustus (Table 3)


Figure 8 Percentage contribution of zooplankton groups in the mean total abundance of zooplanktonat the sites examined in the Barycz river


Table 5 Spearmanrsquos significant correlations between richness and the values of environmental factors(P lt 005)

Variable Pelagic Rotifera Benthic Rotifera Cladocera Copepoda

Chlor_a 028 023 039 041Velocity minus035ND 032 036DCP minus022NCO 031 035TPelRotR 049 031 055 047TBenRotR 031TClaR 060 062 036TCopR 027 022 031 042

NotesChlor_a content of chlorophyll a Velocity current velocity ND number of dams above the site in the Barycz river DCPdistance between the site in the Barycz river and the closest carp pond in the pond system NCO number of carp pond out-lets above the site in the Barycz river TPelRotR richness of pelagic rotifers in the closest tributary above the site in the Baryczriver TBenRotR richness of benthic rotifers in the closest tributary above the site in the Barycz river TClaR richness ofcladocerans in the closest tributary above the site in the Barycz river TCopR richness of copepods in the closest tributaryabove the site in the Barycz river

Impact of environmental variablesAt the Barycz sites richness of each group positively correlated with the chlorophyll acontent (P lt 005) (Table 5) Pelagic rotifers and cladocerans richness also positivelycorrelated with the values of ND and NCO (P lt 005) Moreover a negative correlationbetween the richness of copepods vs the current velocity and the DCP was observed(P lt 005) In the Barycz richness of each group revealed a positive correlation with therichness of the same group in the closest tributary (carp pond outlet) (P lt 005)

The abundance in the Barycz a pattern of Spearmanrsquos significant correlation coefficientssimilar to that of richness was observed (Table 6) Each group correlated positively with thechlorophyll a content and negatively with the current velocity (P lt 005) Abundance ofcopepods correlated negatively with the DCP values (P lt 005) Abundance of each group


Table 6 Spearmanrsquos significant correlations between abundance and the values of environmental fac-tors (P lt 005)

Pelagic Rotifera Benthic Rotifera Cladocera Nauplii Cyclopoida Copepoda

Chlor_a 032 030 050 045 040Velocity minus020 minus018 minus029 minus029 minus032ND 033 028DCP minus026NCO 034 028TPelRotA 081 057 072 066 068TBenRotA 039 029TClaA 064 051 087 069 075TNaupCA 060 056 076 082 076TCopA 063 055 079 070 084

NotesChlor_a content of chlorophyll a Velocity current velocity ND number of dams above the site in the Barycz river DCPdistance between the site in the Barycz river and the closest carp pond in the pond system NCO number of carp pond out-lets above the site in the Barycz river TPelRotA abundance of the pelagic rotifers in the closest tributary above the site inthe Barycz river TBenRotA abundance of benthic rotifers in the closest tributary above the site in the Barycz river TClaAabundance of cladocerans in the closest tributary above the site in the Barycz river TNaupCA abundance of copepods Nau-plii in the closest tributary above the site in the Barycz river TCopA abundance of copepods in the closest tributary abovethe site in the Barycz river

correlated positively with the abundance of the same group in the closest tributary (carppond outlet) (P lt 005)

DISCUSSIONTask 1 A comparison of the zooplankton communities between thefree-flowing sections and impounded sections of the BaryczSpatial pattern of zooplankton richness and abundance in the Barycz shows that the valueof the zooplankton parameters increases with the distance from the river source RiverContinuumConcept (Vannote et al 1980) defines this as a phenomenon typically occurringin large rivers However in case of the Barycz continuum it was the dam impoundmentsthat affected the zooplankton communities as was seen by the increase in species numbersright after the dams Generally this phenomenon is discussed in the context of largerivers with large dams that create large reservoirs In such large reservoirs richness andabundance of zooplankton is similar to that of lakes (Akopian Garnier amp Pourriot 1999Doi et al 2008 Pourriot Rougier amp Miquelis 1997 Żurek amp Dumnicka 1989) In regardwith the present study results we could state that also small dams cause significant growthin zooplankton richness and abundance between the upstream and the downstream Asimilar pattern of zooplankton community distribution in a small river impounded byhuman-made dams or beaver dams was observed by Czerniawski (2013) Czerniawski ampDomagala (2014) and Zhou et al (2008) We observed that in the impoundments of theBarycz the zooplankton richness and abundance were high and comparable to or evenhigher than those in typical temperate limnetic basins eg eutrophic lakes or reservoirs(Gołdyn amp Kowalczewska-Madura 2008 Karabin Ejsmont-Karabin amp Kornatowska 1997Lair 2006)


The main variables that contribute to increase the richness and abundance ofzooplankton in the Barycz are the decrease of the current velocity longer waterretention time or greater areas of open-water zones a higher number of slackwater areasfloodplains and adjacent water bodies (Richardson 1992 Zhou et al 2008 Nielsen et al2013 Czerniawski amp Domagala 2014) The majority of microfauna including freshwaterzooplankton is unable to persist if the current velocity is higher than 01 m sminus1 (Lair 2006Richardson 1992) Such low current velocity values noted at the dam sites in the Baryczwere favorable for the occurrence of zooplankton and for the increase of their populations

The phenomenon that many species were observed in the Barycz but not in the pondoutlets indicates that the dams provided advantageous conditions for the development ofnew species (not observed in upstream and in the carp pond outlets) This refers especiallyto small cladocerans (Alonidae) and littoral rotifers (Euchlanis spMytilina sp) occurringin an environment associated with macrophytes (Rybak amp Błędzki 2010) The more rapidincrease in the richness of the abovementioned taxa and the maintained high densityof zooplankton in the impoundments was possible because features typical of stagnantwater basins covered by macrophytes appeared in the impoundments (Czerniawski2013 Czerniawski amp Domagala 2014 Radwan 2004 Zhou et al 2008) Therefore alteredconditions in the impoundments led to the appearance of new species of pelagic epiphyticand epilithic rotifers and crustaceans and in turn the growth of the zooplanktonabundance (Czerniawski 2013 Czerniawski Pilecka-Rapacz amp Domagala 2013 Nielsenet al 2013 Richardson 1992) Grabowska Ejsmont-Karabin amp Karpowicz (2013) andCzerniawski amp Pilecka-Rapacz (2011) Grabowska Ejsmont-Karabin amp Karpowicz (2013)also observed a percentage domination in the abundance of small cladocerans in a shallowriverine section covered by macrophytes Richardson (1992) and De Bie et al (2008) foundthat the predominance of small cladocerans in running waters may be due to the factthat these species live in close association with the substratum or exhibit a strong habitatselection in favor of well-structured littoral zones which may reduce their vulnerability todownstream washout The bed covered with macrophytes is the key factor that positivelyaffects the richness of zooplankton (Kornijow et al 2005 Kuczynska-Kippen amp Nagengast2006) In the impoundments of the Barycz numerous slackwater areas were observedfrom which zooplankton could be washed into the main channel (Czerniawski 2013Nielsen Gigney amp Watson 2010 Richardson 1992) Very good trophic conditions forfilter-feeding plankters could have occurred in the Barycz dam impoundments becauseof the high concentration of chlorophyll a Richness and abundance of each zooplanktongroup were significantly and positively correlated with the chlorophyll a values whichwere also higher in the impoundments than in the lotic section These effects can bedue to the associated improved nutritional conditions for filter-feeding plankters Sucha correlation is more frequently observed in stagnant waters (Gołdyn amp Kowalczewska-Madura 2008 Kamarainen et al 2008 Levesque Beisner amp Peres-Neto 2010) and slow-flowing waters (Czerniawski 2012 Czerniawski Slugocki amp Kowalska-Goralska 2016)Despite low densities of Euchlanis spMytilina sp and Alonidae they were good indicatorsof the changes in the zooplankton communities in the dammed Barycz river So notonly macroinvertebrates or ichthyofauna react on the anthropogenic changes in river bed


PerhapsWater Framework Directive (WFD) should take into account also the zooplanktonto biological evaluation of rivers However few years ago zooplankton was proposed asa good bioindicator of the lakes conditions Zooplankton may play a pivotal role inthe trophic network of stagnant basins ecosystems but it has not been included in theWFD guidelines as part of biological evaluation despite that many authors have shownstrong indicative properties of zooplankton (Jeppesen et al 2011 Ejsmont-Karabin 2012Ejsmont-Karabin amp Karabin 2013)

It is generally known that zooplankton disperse passively in aquatic ecosystems and theycan colonize new habitats (Havel amp Shurin 2004) Also zooplankton transfer from lakesand reservoirs into the river is well documented (eg Basu amp Pick 1997 Pourriot Rougieramp Miquelis 1997 Czerniawski amp Domagala 2014) Drifting zooplankton can colonizethe river if its bed offer zones with low current velocity or with stagnant water egslackwaters impoundments floodplains (Czerniawski amp Sługocki 2017 Czerniawski ampSługocki 2018) The Barycz is a kind of impoundmentndashcascade system in which richnessand abundance of zooplankton increase with the number of dams The drift from theupstream impoundments would influence richness and abundance in the upstream andthe dam sites That is because what is present in a dam site would first have to driftthrough an upstream site to get to a dam site The dam sites provide a place for driftingzooplankton to proliferate and increase in abundance and as a result rare species (egEuchlanis spMytilina sp) pelagic rotifers and small cladocerans are more easily detectedwhen sampling Richness and abundance of pelagic rotifers and cladocerans correlatedpositively with the number of dams in river Thus passive zooplankton dispersion into theimpoundments could be affected by the impoundments upstream and mainly Rotiferathat demonstrate the best ability to colonize new habitats by short life span reproducethrough cyclical parthenogenesis production the resting eggs that are easily transferred(Ejsmont-Karabin amp Kruk 1998 Wallace 2002)

The zooplankton abundance was reduced along the section stretching from the damsites to the lotic sections downstream The decreased richness and density of zooplanktonat the downstream sites typically occurs in the outlet sections of lakes or reservoirs and itdepend on level of turbulence values of discharge and current velocities Higher valuesof these variables can have negative effect on fish predation on zooplankton grazingby suspension-feeding filter-feeding or net-spinning of macrozoobenthos or settling tosediments (Chang et al 2008 Czerniawski Pilecka-Rapacz amp Domagala 2013 Nielsen etal 2013 Thorp amp Casper 2003) In Barycz relatively low values of current velocity wereobserved However with the distance from the last dam the zooplankton abundance andchlorophyll a concentration was rapidly reduced so the impact of dam sites and carpponds outlets on the zooplankton in lower section of Barycz and on their recipientmdashOderis rather small

Task 2 A comparison of the zooplankton communities between thecarp pond outlets and the riverIt is certain that because of the dam presence richness and abundance of zooplankton inthe Barycz were high and they were higher than in the lotic sections of other rivers and


even in the reservoirs of other larger rivers (Akopian Garnier amp Pourriot 1999 Doi et al2008 Pourriot Rougier amp Miquelis 1997) This pattern was affected by an additional factornamely a connection between the river and the carp pond outlets which could have allowedthe zooplankton to drift passively We observed a similarity in zooplankton abundancebetween the carp pond outlets and the subsequent sites in the Barycz This indicates thatthere is a influence of the carp pond outlets on the zooplankton abundance in the BaryczWhile the differences between the carp pond outlets and the impoundments in the Baryczwere particularly apparent when it comes to richness and species similarity

It is surprising that crustaceans were the abundance dominants at all sites of theBarycz The zooplankton in rivers as well as small and large reservoirs mainly consistof Cyclopoida nauplii and minor species of rotifers (Akopian Garnier amp Pourriot 1999Czerniawski amp Domagala 2014Doi et al 2008 Pourriot Rougier amp Miquelis 1997Zhou etal 2008) In the present study we have observed a different pattern which was found in anon-typical river system It was a carp pond outletmdashimpoundmentmdashriver system in whichthe composition of dominants depended on the sites that provided the best conditions forcolonization and development In this case these were primarily carp ponds whose outletscarried zooplankton mass into the Barycz The impoundments in which zooplankton fromthe tributaries remained and could maintain its abundance at a stable level played only aminor role Dominants in the pond outlets that were carried into the Barycz were smallcladocerans (bosminids and chydorids) that once passively drifted into the Barycz anddominated in the river as well Bosminids and chydorids are small species that abundantlycolonize both the pelagial and the littoral of either shallow and deep reservoirs in whichthey can be dominant (Gasiorowski amp Szeroczynska 2004 Rybak amp Błędzki 2010 Soto ampDe los Rios 2006)

Cottenie et al (2003) claimed that connected water basins have similar zooplanktonstructures if they are environmentally similar Results of our study show that the spatialpattern of zooplankton communities in the Barycz river confirms this statement Thenumber of taxa at environmentally similar sites (ie at different dam sites different loticsites and different tributary sites) was similar although the species similarity between thesesites was not high Taxonomic similarity achieved high values between the subsequent siteseg a tributary vs an impoundment or lotic section sites and dam sites vs lotic sectionsites Hence the number of species was comparable at similar sites however these specieswere replaced by other species This fact demonstrates the high influence of the tributariesand the dam sites on the development of zooplankton species structure in downstreamlocations

To fully address the problem of carp pond influence on zooplankton population in theBarycz we would have to examine the zooplankton in the ponds and its similarity to theBarycz However it was not the objective of this study We can be certain that the influxof zooplankton in the carp pond outlets would provide enough data to determine theinfluence of carp ponds on zooplankton and the Barycz That is because plankters foundin ponds dispersed passively to the outlets which was proved by the similarities foundbetween zooplankton communities in water basins and their outlet sections


CONCLUSIONSpatial changes in the zooplankton composition in the Barycz river reflected the effects ofphysical changes induced by the dam impoundments and by dispersion of zooplanktonfrom the carp ponds outlets In the case of pelagic rotifers the higher the mean richnessand abundance in the tributaries the higher values of this parameters were observedat the subsequent sites below a tributary in the Barycz Since the abundance of mostgroups (except for benthic rotifers) in the tributaries was similar to that at lower sitesin the Barycz the influence of the tributaries on the abundance in the dam and loticsections is significant Similarly significant was the influence of the impoundments on thezooplankton abundance in the lotic sections The carp ponds outlets cause a large influxof zooplankton biomass to the river Moreover the river itself in its impounded sectionsprovides advantageous conditions for retention and colonization by a high abundanceof zooplankton dispersing from the carp ponds and for the development of new species(not observed in the upstream) which in turn increases richness This pattern was themost noticeable in the case of the crustaceans (cladocerans and copepods) which werecharacterized by a higher mean richness at the dam sites than in the tributaries TheBarycz is kind of an impoundmentndashcascade system in which richness and abundanceof zooplankton increase with the number of dams However richness and abundancedecrease in case of the last site despite the fact that there is a number of dams below it andno pond influence This shows that there is a clear influence of carp pond outlets whichare the source of zooplankton in the Barycz

The presented study demonstrated how significant the effect of alterations to the riverbed as well as alterations to the water reservoirs in its catchment area (influx of thezooplankton from carp ponds) is to the biological changes in the river The influx of liveorganic matter from the carp ponds and the dams has an impact on the zooplanktoncommunities in the river downstream The influx of zooplankton from carp pondsundoubtedly affected the increase in the zooplankton abundance in the river while thedams had an effect on retaining this abundance and increasing richness

ADDITIONAL INFORMATION AND DECLARATIONS

FundingThis work is supported by Wrocław Centre of Biotechnology programme The LeadingNational Research Centre (KNOW) for years 2014ndash2018 The funders had no role in studydesign data collection and analysis decision to publish or preparation of the manuscript

Grant DisclosuresThe following grant information was disclosed by the authorsWrocław Centre of Biotechnology programme The Leading National Research Centre(KNOW)

Competing InterestsThe authors declare there are no competing interests


Author Contributionsbull Robert Czerniawski and Monika Kowalska-Goacuteralska conceived and designedthe experiments performed the experiments analyzed the data contributedreagentsmaterialsanalysis tools prepared figures andor tables authored or revieweddrafts of the paper approved the final draft

Data AvailabilityThe following information was supplied regarding data availability

The raw data are provided as Supplemental Files

Supplemental InformationSupplemental information for this article can be found online at httpdxdoiorg107717peerj5087supplemental-information

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Allan JD Castillo MM 2007 Stream ecology structure and function of running watersDordrecht Springer Science amp Business Media

Basu BK Pick FR 1997 Phytoplankton and zooplankton development in a lowlandtemperate river Journal of Plankton Research 19237ndash253DOI 101093plankt192237

Chang KH Doi H Imai H Gunji F Nakano S 2008 Longitudinal changes in zoo-plankton distribution below a reservoir outfall with reference to river planktivoryLimnology 9125ndash133 DOI 101007s10201-008-0244-6

Cottenie K Michels E Nuytten N DeMeester L 2003 Zooplankton metacommunitystructure regional vs local processes in highly interconnected ponds Ecology84991ndash1000 DOI 1018900012-9658(2003)084[0991zmsrvl]20co2

Cumming GS 2004 The impact of low-head dams on fish species richness in WisconsinUSA Ecological Applications 141495ndash1506 DOI 10189003-5306

Czerniawski R 2012 Spatial pattern of potamozooplankton community of the slowlyflowing fishless stream in relation to abiotic and biotic factors Polish Journal ofEcology 60323ndash338

Czerniawski R 2013 Zooplankton community changes between forest and meadowsections in small headwater streams NW Poland Biologia 68448ndash458DOI 102478s11756-013-0170-x

Czerniawski R Domagala J 2014 Small dams profoundly alter the spatial and temporalcomposition of zooplankton communities in running waters International Review ofHydrobiology 99300ndash311 DOI 101002iroh201301674

Czerniawski R Pilecka-Rapacz M 2011 Summer zooplankton in small rivers inrelation to selected conditions Central European Journal of Biology 6659ndash674DOI 102478s11535-011-0024-x


Czerniawski R Pilecka-Rapacz M Domagala J 2013 Zooplankton communities ofinter-connected sections of lower River Oder (NW Poland) Central EuropeanJournal of Biology 818ndash29 DOI 102478s11535-012-0110-8

Czerniawski R Sługocki Ł 2017 Analysis of zooplankton assemblages from man-madeditches in relation to current velocity Oceanological and Hydrobiological Studies46199ndash211

Czerniawski R Sługocki Ł 2018 A comparison of the effect of beaver and human-madeimpoundments on stream zooplankton Ecohydrology DOI 101002eco1963

Czerniawski R Slugocki L Kowalska-Goralska M 2016 Diurnal changes of zooplank-ton community reduction rate at lake outlets and related environmental factorsPLOS ONE 11 DOI 101371journalpone0158837

De Bie T Declerck S Martens K DeMeester L Brendonck L 2008 A compar-ative analysis of cladoceran communities from different water body typespatterns in community composition and diversity Hydrobiologia 59719ndash27DOI 101007s10750-007-9222-y

Doi H Chang KH Ando T Imai H Nakano SI Kajimoto A Katano I 2008 Driftingplankton from a reservoir subsidize downstream food webs and alter communitystructure Oecologia 156363ndash371 DOI 101007s00442-008-0988-z

Dufour S Pieacutegay H 2009 From the myth of a lost paradise to targeted river restorationforget natural references and focus on human benefits River Research and Applica-tions 25568ndash581 DOI 101002rra1239

Ejsmont-Karabin J 2012 The usefulness of zooplankton as lake ecosystem indicatorsRotifer Trophic State Index Polish Journal of Ecology 60(2)339ndash350

Ejsmont-Karabin J Karabin A 2013 The suitability of zooplankton as lake ecosystemindicator Crustacean trophic state index Polish Journal of Ecology 61(3)561ndash573

Ejsmont-Karabin J KrukM 1998 Effects of contrasting land use on free-swimmingrotifer communities of streams in Masurian Lake District Poland Hydrobiologia387241ndash249 DOI 101023a1017081407452

GąbkaM Dolata PT Antonowicz R 2007 New localities of the Chinese clam Sinan-odonta woodiana (Lea 1834)(Bivalvia Unionidae) in the Barycz river valley(Wielkopolska Region) Folia Malacologica 1571ndash73

Gasiorowski M Szeroczynska K 2004 Abrupt changes in Bosmina (CladoceraCrustacea) assemblages during the history of the Ostrowite Lake (northern Poland)Hydrobiologia 526137ndash144 DOI 101023BHYDR000004159209564e6

Gołdyn R Kowalczewska-Madura K 2008 Interactions between phytoplankton andzooplankton in the hypertrophic Swarzędzkie Lake in western Poland Journal ofPlankton Research 3033ndash42 DOI 101093planktfbm086

GrabowskaM Ejsmont-Karabin J Karpowicz M 2013 Reservoir-river relationships inlowland shallow eutrophic systems an impact of zooplankton from hypertrophicreservoir on river zooplankton Polish Journal of Ecology 61759ndash768

Havel J Shurin J 2004Mechanisms effects and scales od dispersal in freshwaterzooplankton Limnology and Oceanography 491229ndash1238DOI 104319lo2004494_part_21229


Jeppesen E Notildeges P Davidson TA Haberman J Notildeges T Blank K Lauridsen TLSoslashndergaardM Sayer C Laugaste R Johansson LS Bjerring R Amsinck SL 2011Zooplankton as indicators in lakes a scientific-based plea for including zooplanktonin the ecological quality assessment of lakes according to the European Water Frame-work Directive (WFD) Hydrobiologia 676279 DOI 101007s10750-011-0831-0

Jones J KnowltonM Obrecht D Cook E 2004 Importance of landscape variables andmorphology on nutrients in Missouri reservoirs Canadian Journal of Fisheries andAquatic Sciences 611503ndash1512 DOI 101139f04-088

Kamarainen AM Rowland FE Biggs R Carpenter SR 2008 Zooplankton and the totalphosphorusmdashchlorophyll a relationship hierarchical Bayesian analysis of mea-surement error Canadian Journal of Fisheries and Aquatic Sciences 652644ndash2655DOI 101139f08-161

Karabin A Ejsmont-Karabin J Kornatowska R 1997 Eutrophication processesin a shallow macrophyte-dominated lakemdashfactors influencing zooplanktonstructure and density in Lake Luknajno (Poland) Hydrobiologia 342401ndash409DOI 101023a1017003810282

Kloskowski J 2011 Impact of common carp Cyprinus carpio on aquatic communitiesdirect trophic effects versus habitat deterioration Fundamental and Applied Limnol-ogy 178245ndash255 DOI 1011271863-913520110178-0245

Kornijow R Vakkilainen K Horppila J Luokkanen E Kairesalo T 2005 Impacts of asubmerged plant (Elodea canadensis) on interactions between roach (Rutilus rutilus)and its invertebrate prey communities in a lake littoral zone Freshwater Biology50262ndash276 DOI 101111j1365-2427200401318x

Kuczynska-Kippen NM Nagengast B 2006 The influence of the spatial structure of hy-dromacrophytes and differentiating habitat on the structure of rotifer and cladocerancommunities Hydrobiologia 559203ndash212 DOI 101007s10750-005-0867-0

Lair N 2006 A review of regulation mechanisms of metazoan plankton in riverineecosystems aquatic habitat versus biota River Research and Applications 22567ndash593DOI 101002rra923

Levesque S Beisner BE Peres-Neto PR 2010Meso-scale distributions of lake zooplank-ton reveal spatially and temporally varying trophic cascades Journal of PlanktonResearch 321369ndash1384 DOI 101093planktfbq064

Meijer ML Lammens E Raat AJP GrimmMP Hosper SH 1990 Impact of cyprinidson zooplankton and algae in 10 drainable ponds Hydrobiologia 191275ndash284DOI 101007bf00026063

Nielsen DL Gigney HWatson G 2010 Riverine habitat heterogeneity the role ofslackwaters in providing hydrologic buffers for benthic microfauna Hydrobiologia638181ndash191 DOI 101007s10750-009-0039-8

Nielsen DL Podnar KWatts RJ Wilson AL 2013 Empirical evidence linking increasedhydrologic stability with decreased biotic diversity within wetlands Hydrobiologia70881ndash96 DOI 101007s10750-011-0989-5


NieoczymM Kloskowski J 2014 The role of body size in the impact of common carpCyprinus carpio o(n) water quality zooplankton and macrobenthos in pondsInternational Review of Hydrobiology 99212ndash221 DOI 101002iroh201301644

Nogrady TWallace RL Snell TW 1993Guides to the identification of the microinverte-brates of the continental waters of the world Hague SPB Academic Publishers

Oksanen J Blanchet FG Friendly M Kindt R Legendre P McGlinn D Minchin PROrsquoHara RB Simpson GL Solymos P Henry H Stevens H Szoecs E Wagner H2016 Vegan Community Ecology Package R Package Version 23-5 Available athttpCRANR-projectorgpackage=vegan

Otrsquoahelrsquoovaacute H Valachovič M 2002 Effects of the Gabčiacutekovo hydroelectric-station onaquatic vegetation of the Danube river (Slovakia) Preslia 74323ndash331

Parkos JJ Santucci VJ Wahl DH 2003 Effects of adult common carp (Cyprinuscarpio)on multiple trophic levels in shallow mesocosms Canadian Journal ofFisheries and Aquatic Sciences 60182ndash192 DOI 101139f03-011

Pourriot R Rougier C Miquelis A 1997 Origin and development of river zooplanktonexample of the Marne Hydrobiologia 345143ndash148 DOI 101023A1002935807795

Radwan S 2004 Rotifers Łoacutedź Uniwersytet ŁoacutedzkiRahmanMM VerdegemM Nagelkerke L WahabMAMilstein A Verreth J 2008

Effects of common carp Cyprinus carpio (L) and feed addition in rohu Labeo rohita(Hamilton) ponds on nutrient partitioning among fish plankton and benthosAquaculture Research 3985ndash95 DOI 101111j1365-2109200701877x

RichardsonWB 1992Microcrustacea in flowing watermdashexperimental-analysis ofwashout times and a field-test Freshwater Biology 28217ndash230DOI 101111j1365-24271992tb00578x

Rybak JI Błędzki LA 2010 Planktonic crustaceans of freshwaters Warszawa UniwersytetWarszawski

Soranno PA Cheruvelil KS Wagner TWebster KE BremiganMT 2015 Effects of landuse on lake nutrients the importance of scale hydrologic connectivity and regionPLOS ONE 10e0135454 DOI 101371journalpone0135454

Soto D De los Rios P 2006 Influence of trophic status and conductivity on zooplanktoncomposition in lakes and ponds of Torres del Paine National Park (Chile) Biologia61541ndash546 DOI 102478s11756-006-0088-7

Thorp JH Casper AF 2003 Importance of biotic interactions in large rivers anexperiment with planktivorous fish dreissenid mussels and zooplankton in the StLawrence River River Research and Applications 19265ndash279 DOI 101002rra703

Ullah KA Jiang J Wang P 2018 Land use impacts on surface water quality by statisticalapproaches Global Journal of Environmental Science and Management 4231ndash250

Vannote RL Minshall GW Cummins KW Sedell JR Cushing CE 1980 The rivercontinuum concept Canadian Journal of Fisheries and Aquatic Sciences 37130ndash137DOI 101139f80-017

Wallace RL 2002 Rotifers exquisite metazoans Integrative amp Comparative Biology42(3)660ndash667 DOI 101093icb423660


WuN Tang T Fu X JiangW Li F Zhou S Cai Q Fohrer N 2010 Impacts of cascaderun-of-river dams on benthic diatoms in the Xiangxi River China Aquatic Sciences72117ndash125 DOI 101007s00027-009-0121-3

Zawal A Sulikowska-Drozd A Stępień E Jankowiak Ł Szlauer-Łukaszewska A2016 Regeneration of the molluscan fauna of a small lowland river after dredgingFundamental and Applied LimnologyArchiv Fuumlr Hydrobiologie 187281ndash293DOI 101127fal20160753

Zhou SC Tang TWuNC Fu XC Cai QH 2008 Impacts of a small dam on riverinezooplankton International Review of Hydrobiology 93297ndash311DOI 101002iroh200711038

Żurek R Dumnicka E 1989 The rate of population in a river after leasing a damreservoir Archiv fuumlr Hydrobiologie Ergebnisse der Limnologie 33549ndash561


2009 Zawal et al 2016) Consequently all the technical measures which alter the river-bedand the hydrological conditions affect the biological functioning of the lotic sections

Human-made dams are one of the most important technical measures that break theriver continuum Oftentimes they cause irreversible alterations in rivers and distort theirnatural flow (Allan amp Castillo 2007) Such alterations are reflected in physicochemical andbiological variables as well as the loss and replacement of typical lotic species by typicalstagnant water species A large number of studies examine how large dams in large riverscause changes in environmental conditions whereas few papers address the impact ofsmall dams in small rivers or streams However small dams impounding a water of upto 4 m cause similar changes in river ecosystems albeit on a much smaller scale In smallrivers even small dams can affect the flora and fauna composition by inducing rapidchanges in hydrological and physicochemical variables (Cumming 2004 Wu et al 2010Zhou et al 2008) Small dams create distinct physical and ecological conditions that arerelatively different from the ones found in free-flowing lotic sections This is manifested bya reduction of current velocity increase of water retention time and increase of nutrientcontent

These new conditions eg long water retention time and low current velocity aresuitable for the growth of zooplankton populations that in turn are a good indicatorof hydrological changes (Czerniawski amp Domagala 2014 Otrsquoahelrsquoovaacute amp Valachovič 2002Zhou et al 2008) Zooplankton can develop in stagnant waters or in slow-flowing waterswith current velocities lower than 01 m sminus1 (Czerniawski amp Domagala 2014 Zhou etal 2008) Given that zooplankton reacts rapidly to the hydrological changes caused bydams Until now the influence of dams on zooplankton communities has been studiedprimarily in large rivers with dammed water up to more than 15 m (Akopian Garnieramp Pourriot 1999 Doi et al 2008 Pourriot Rougier amp Miquelis 1997 Żurek amp Dumnicka1989) However only a few studies have investigated the influence of small dams onzooplankton communities (Czerniawski amp Domagala 2014 Zhou et al 2008) Smalldams promote the formation of biotopes of the ecotone type in which the zooplanktoncommunity develops features similar to or different from those communities in lakes andlarge reservoirs (Czerniawski amp Domagala 2014 Zhou et al 2008)

Another process leading to alterations in a man-changed environment is catchmenttransformation ie creation of retention reservoirs or fish ponds joined with mainchannel of the river The amount of dead and live organic matter (including zooplankton)significantly increases in such reservoirs (Kloskowski 2011 Meijer et al 1990 Rahman etal 2008) An example of artificial reservoirs are carp ponds which lead to the increase inorganic matter and cause an influx of the organic matter to the rivers High biomass ofcommon carp cause an increase of nutrients turbidity and suspended solids hence thesebasins have a strong influence onwater quality and aquatic community structure (Nieoczymamp Kloskowski 2014 Parkos Santucci amp Wahl 2003) The dispersion of carp-pond plankterscan enrich the river with high densities or new zooplankton species The inorganic andorganic nutrients in the water column can drift to the outlet section thereafter and thenbe dispersed into rivers


























Velocity(m sminus1)

ND DCP (km) NCO













Table 2 (continued)












Pelagic Rotifera R1

D1

R2

D2

D3

D4

Cladocera R1

Copepoda R1












Pelagic Rotifera R1

Cladocera R1

T2

Nauplii R1

T2

Copepoda R1

T2

T3
















































































































































Velocity(m sminus1)

ND DCP (km) NCO













Table 2 (continued)












Pelagic Rotifera R1

D1

R2

D2

D3

D4

Cladocera R1

Copepoda R1












Pelagic Rotifera R1

Cladocera R1

T2

Nauplii R1

T2

Copepoda R1

T2

T3











































































































































Velocity(m sminus1)

ND DCP (km) NCO













Table 2 (continued)












Pelagic Rotifera R1

D1

R2

D2

D3

D4

Cladocera R1

Copepoda R1












Pelagic Rotifera R1

Cladocera R1

T2

Nauplii R1

T2

Copepoda R1

T2

T3






































































































































Velocity(m sminus1)

ND DCP (km) NCO













Table 2 (continued)












Pelagic Rotifera R1

D1

R2

D2

D3

D4

Cladocera R1

Copepoda R1












Pelagic Rotifera R1

Cladocera R1

T2

Nauplii R1

T2

Copepoda R1

T2

T3

































































































































Velocity(m sminus1)

ND DCP (km) NCO













Table 2 (continued)












Pelagic Rotifera R1

D1

R2

D2

D3

D4

Cladocera R1

Copepoda R1












Pelagic Rotifera R1

Cladocera R1

T2

Nauplii R1

T2

Copepoda R1

T2

T3



























































































































Velocity(m sminus1)

ND DCP (km) NCO













Table 2 (continued)












Pelagic Rotifera R1

D1

R2

D2

D3

D4

Cladocera R1

Copepoda R1












Pelagic Rotifera R1

Cladocera R1

T2

Nauplii R1

T2

Copepoda R1

T2

T3





























































































































Table 2 (continued)












Pelagic Rotifera R1

D1

R2

D2

D3

D4

Cladocera R1

Copepoda R1












Pelagic Rotifera R1

Cladocera R1

T2

Nauplii R1

T2

Copepoda R1

T2

T3
























































































































Table 2 (continued)












Pelagic Rotifera R1

D1

R2

D2

D3

D4

Cladocera R1

Copepoda R1












Pelagic Rotifera R1

Cladocera R1

T2

Nauplii R1

T2

Copepoda R1

T2

T3




























































































































Pelagic Rotifera R1

D1

R2

D2

D3

D4

Cladocera R1

Copepoda R1












Pelagic Rotifera R1

Cladocera R1

T2

Nauplii R1

T2

Copepoda R1

T2

T3































































































































Pelagic Rotifera R1

Cladocera R1

T2

Nauplii R1

T2

Copepoda R1

T2

T3




























































































































Pelagic Rotifera R1

Cladocera R1

T2

Nauplii R1

T2

Copepoda R1

T2

T3






































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































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Spatial changes in zooplankton communities in a strong ... › articles › 5087.pdf · communis, Sparganiun erectum), whereas the central zone of the bed impoundment was covered