Species Of Rotifera Research Articles

Modeling species richness and abundance of phytoplankton and zooplankton in radioactively contaminated water bodies

Water bodies polluted by the Mayak nuclear plant in Russia provide valuable information on multi-generation effects of radioactive contamination on freshwater organisms. For example, lake Karachay was probably the most radioactive lake in the world: its water contained ∼2 × 107 Bq/L of radionuclides and estimated dose rates to plankton exceeded 5 Gy/h. We performed quantitative modeling of radiation effects on phytoplankton and zooplankton species richness and abundance in Mayak-contaminated water bodies. Due to collinearity between radioactive contamination, water body size and salinity, we combined these variables into one (called HabitatFactors). We employed a customized machine learning approach, where synthetic noise variables acted as benchmarks of predictor performance. HabitatFactors was the only predictor that outperformed noise variables and, therefore, we used it for parametric modeling of plankton responses. Best-fit model predictions suggested 50% species richness reduction at HabitatFactors values corresponding to dose rates of 104-105 μGy/h for phytoplankton, and 103-104 μGy/h for zooplankton. Under conditions similar to those in lake Karachay, best-fit models predicted 81-98% species richness reductions for various taxa (Cyanobacteria, Bacillariophyta, Chlorophyta, Rotifera, Cladocera and Copepoda), ∼20-300-fold abundance reduction for total zooplankton, but no abundance reduction for phytoplankton. Rotifera was the only taxon whose fractional abundance increased with contamination level, reaching 100% in lake Karachay, but Rotifera species richness declined with contamination level, as in other taxa. Under severe radioactive and chemical contamination, one species of Cyanobacteria (Geitlerinema amphibium) dominated phytoplankton, and rotifers from the genus Brachionus dominated zooplankton. The modeling approaches proposed here are applicable to other radioecological data sets. The results provide quantitative information and easily interpretable model parameter estimates for the shapes and magnitudes of freshwater plankton responses to a wide range of radioactive contamination levels.

Kiğı Baraj Gölü (Bingöl-Türkiye)'nün Zooplankton Faunası Üzerine Taksonomik Bir Çalişma

The present study was conducted to determine zooplankton fauna of Kiğı Dam Lake during September 2012 and August 2013 seasonally. The zooplankton samples were collected by using plankton net with the mesh size of 55µm horizontally and preserved in 4% formaldehyde. Total 22 taxa (16 Rotifera, 4 Cladocera, and 2 Copepoda) were identified in Kiğı Dam Lake. Ascomorpha saltans, Asplanchna priodonta, Brachionus angularis, Cephalodella gibba, Euchlanis dilatata, Kellicottia longispina, Keratella cochlearis, Keratella quadrata, Lecane luna, Lecane lunaris, Notholca squamula, Polyarthra dolichoptera, Rotaria rotatoria, Synchaeta pectinata, Synchaeta oblonga, Trichocerca capucina from Rotifera species; Bosmina longirostris, Chydorus sphaericus, Daphnia cucullata, Daphnia longispina from Cladocera species; Acanthodiaptomus denticornis, Cyclops vicinus from Copepoda species are new records for this dam lake. Zooplankton samples were consisted of 72.7% Rotifera, 18.2% Cladocera, and 9.1% Copepoda.

Hoşrük Çayı (Elazığ-Türkiye) Zooplanktonu

Hoşrük Çayı‘ndan Mart 2104 - Şubat 2015 tarihleri arasında aylık olarak 3 istasyondan zooplankton numuneleri alınmıştır. Çaya ait su sıcaklığı, çözünmüş oksijen ve pH değerleri arazide portatif ölçüm cihazları ile belirlenmiştir. Shannon Wiever (H'), Simpson (D) ve Margalef (M) indeks değerleri ilgili formüller kullanılarak aylık olarak hesaplanmıştır. Araştırma süresince toplam 28 zooplankton türü teşhis edilmiştir. Bu türler içinde 18 tür Rotifera, 8 tür Cladocera 2 tür ise Copepodan grubundandır. Rotiferler takson sayısı, birey sayısı ve ortaya çıkış sıklığı bakımından ilk sırada yer almıştır. Rotiferlerden Polyarthra dolichoptera 11 örneklemede tespit edilerek, tüm zooplankton türleri içinde en fazla ortaya çıkan tür olmuştur. Copepoda‘dan Cyclops vicinus 9 ay gözlenerek ikinci dominant tür olmuştur. Mayıs ayı en fazla taksonun (20 tür) kaydedildiği ay olurken, ocak ayı en az taksonun (2 tür) kaydedildiği ay olmuştur. Shannon Wiever tür zenginliği indeks değeri (H') en yüksek değerine H= 1,51 ile temmuz ayında ulaşmıştır. Margalef indeks değeri de M=2,22 ile en yüksek mayıs ayında, Simpson indeks değeri D=0,89 ile mart ayında en yüksek değerinde hesaplanmıştır. H' indeks değerinin her ay düşük çıkması çayın tür çeşitliliği bakımından fakir olduğunu göstermektedir.

한국하천호수학회를 통해 본 국내 담수 동물플랑크톤 연구의 역사와 현재, 미래의 연구 동향

This review summarizes the history of freshwater zooplankton research in Korean Society of Limnology and necessary future topics that are remain poorly investigated in South Korea based on main research topics of published articles focusing on lakes, reservoirs, rivers and wetland ecosystems. In Korea, a total 450 freshwater zooplankton species have been reported (85 species of cladocera, ca. 230 species of rotifera since 1939, and 138 species of copepoda), and they cover 10% of total zooplankton species list. In the present paper, we provide recent species list of zooplankton found in Korea and their taxonomic keys. Over periods of 45 years, there are 25 published papers for zooplankton biota in lentic ecosystems in Korean Journal of Ecology and Environment (KJEE). The ecology of zooplankton communities in rivers has focused on the mechanisms involved in regulating their abundance, diversity and spatio-temporal patterns of genus Bosmina and rotifers (genus Brachionus and Keratella) that are most frequently found from Korea. On the other hand, the studies on zooplankton in wetland has focused on Alona, Chydorus and Ceriodaphnia with special emphasis on their relationships with aquatic macrophytes. Even though studies on the freshwater ecosystem in Korea have a long history, a few of studies on zooplankton biota were conducted at rice paddy, Dumbeong and wetlands. During the last two decades, experimental advances in freshwater zooplankton ecology and understanding of structure and function of this biota were made from a series of articles mainly in journal of KJEE. For future studies, quantitative, experimental and interdisciplinary approaches would be key words to understand zooplankton ecology and their roles in aquatic ecosystems under changing environments, and we have suggested necessary zooplankton research fields and future directions.

Zooplankton of mountain and lowland waterbodies of Northwestern India

In 2013–2015, 9 waterbodies situated in mountain and lowland regions of Northwestern India were studied. 46 species of zooplankton organisms were revealed, among them 18 Rotifera species, 20 Cladocera, 8 Copepoda, and 1 species of Anostraca. For this part of India, it was the first time detected 8 Rotifera species, 5 Cladocera, and 2 Copepoda. Cosmopolites and Paleotropic species were registered in all waterbodies studied in the Himalayans and lowland India. Palearctic and Holarctic species — in the Himalayans only. Tropic species were found in lowland India only. Species number and zooplankton species diversity index were low. Zooplankton density was relatively high in one from four mountain lakes and in all lowland waterbodies (99–487 thousands ind./m3). Zooplankton biomass was low (0.04–8.00 g/m3) in both mountain and lowland lakes, in exception two lowland lakes with wind onset and overwintering place for large birds. Rotifera dominated by biomass only in mountain region. Cladocera predominated in zooplankton density and biomass in majority of studied waterbodies. This group was represented by coastal and macrophyte forms which are usual for shallow waterbodies. Copepoda were abundant in five studied waterbodies and basically were represented by Cyclopoida. Calanoida group (Diaptomidae) was revealed in only one lowland lake located in a desert. Macrofiltrators represented the main part of zooplankton trophic structure. Microphages and predators subdominated in zooplankton communities.

Temperature Impact on the Shannon-Wiener Biodiversity Index (BDI) of Zooplankton in Lake Kinneret (Israel)

The Shannon-Wiener Biodiversity Index was implemented for Zooplankton Diversity (BDI) in Lake Kinneret (1970-2001). It was computed based on monthly mean densities in relation to Epilimnetic temperatures. 4, 5 and 9 species of Copepoda, Cladocera and Rotifera, respectively, were included. Direct relations between Epilimnetic temperatures and Zooplankton Bio-Diversity Indexes (BDI) were indicated: Matching was found between low BDI and the high summer temperature and between higher BDI and the low winter temperature as well. Similar correspondence did not indicate annual means of BDI values. Zooplankton density and temperature probably resulted from smoothed confound of the averaged temperature changes. Conclusively, in themonomicticLakeKinneret located in the temperate zone with a high degree of temperature fluctuation, causation of seasonal BDI fluctuations is possible. The consistence of global warming trend might, therefore, enhance the seasonality of BDI values changes with implications for water quality.

Studies on Seasonal Zooplankton Community Structure of Gandak river

The selected sites of Gandak river near Sheetalpur ghat were studied for a period of one year from June 2013 to May 2014 for regular physico-chemical parameters and zooplankton community structure. The study was designed to estimate zooplankton abundance with seasonal repeated collections. The zooplankton community was composed of 08 species of Rotifera, 07 species of Cladocera, 02 species of Copepoda and 01 species of Ostracoda. These Crustaceans were dominant Class throughout the study period. The abundance of zooplankton in the pond follows a sequence as: Rotifera > Cladocera > Copepoda > Ostracoda. There changes in quantitative and qualitative community structure were found directly correlated with abiotic factors during study period.

Zooplankton diversity of drainage system reservoirs at an opencast mine

The aim of this study was to determine the structure of zooplankton in three artificial water reservoirs, the technological function of which is to pre-treat waters from a drainage system of a brown coal open mine by removing inorganic suspension. The background for the zooplankton qualitative and quantitative analyses was the hydrochemical conditions in the individual reservoirs. The greatest zooplankton abundance (N), number of taxa (n), Shannon’s diversity (H'), and species eveness (J') was noted in reservoir Chabielice (Nmean = 1311 ind. L−1, n = 26, H' = 2.09, J' = 0.64) which was dominated by eurytopic Rotifera species (Keratella cochlearis,Keratella tecta,Keratella valga,Polyarthra longiremis,Filinia longiseta). Their abundance was positively correlated with water pH and nutrient concentrations. Reservoir Kamień was characterized by the highest mean values of total suspension (9.6 mg L−1), chlorophyll a (Chl a) content (10.4 μg L−1), and water temperature (20.0 °C). These factors significantly correlated with crustacean biomass. The thermal-oxygenation conditions, low trophic level, and low productivity of the water (Chl a = 5.4 μg L−1) in reservoir Północny determined the overall low zooplankton abundance (Nmean = 153 ind. L−1). Artificial water bodies of opencast mine drainage systems are biologically unstable, but they do have some characteristics of natural ecosystems, and they do take over their functions. Zooplankton is an indicator of their ecological functionality. Knowledge gained about such reservoirs could contribute to decision-making about strategies for water reclamation and how to manage it.

Boztepe Recai Kutan Baraj Gölü (Malatya - Türkiye) zooplankton faunası

Boztepe Baraj Golu’nden Ocak-Aralik 2014 tarihleri arasinda aylik olarak alinan su orneklerinde zooplankton incelenmesi yapilmistir. Calismada teshisi yapilan 33 zooplankton turunden 17 tur Rotifera, 13 tur Cladocera ve 3 tur Copepoda grubundandir. Toplam zooplanktonun en fazla kaydedildigi donem Mayis ayi olmustur (271785 birey/m 3 ). En az birey sayisi ise Subat ayinda kaydedilmistir (5090 birey/m 3 ). En fazla takson sayisi 17 tur ile Ekim ayinda en az tur sayisi ise 5 tur ile Subat ayinda tespit edilmistir. Bulunan butun zooplanktonik turler Boztepe Recai Kutan Baraj Golu icin ilk kayittir. Baraj golunde zooplankton turlerinin toplam birey sayilarina gore Rotifera (% 51,5) baskin grup olup, Cladocera (% 39,4) ve Copepoda (% 9,1) onlari takip eden gruplar olmustur. Keratella cochlearis baskin Rotifer turu olurken K. quadrata onu izlemistir. Bosmina longirostris baskin Cladocera turudur. Cyclops vicinus en cok gozlenen Copepoda turu olmustur. Rotifera diger gruplara gore fazla cesitlilik gostermis ve arastirma donemi boyunca yuksek yogunluklarda ortaya cikmistir. Otrofi indikatoru olan Keratella cochlearis K. quadrata, Bosmina longirostris turlerinin siklikla cok sayida kaydedilmis olmasi golun otrof karakterde olabilecegini dusundurmektedir.

Dynamics of the zooplankton assemblage of Ojirami Reservoir, Edo State, Nigeria

Zooplankton form an important trophic link between phytoplankton and fish in the aquatic food chain. Investigation was carried out on the zooplankton community of Ojirami, Reservoir, Nigeria, to document the composition, abundance and distribution and their interactions with the physico-chemical conditions. Surface water and zooplankton samples were collected from six sampling stations (A, B, C, D, E, and F) monthly from January 2009 to December 2010 and analyzed following standard methods. Twelve out of the 17 physico-chemical conditions showed higher wet season mean levels. The zooplankton community comprised 28 species of Rotifera, 12 Cyclopoida, 17 Cladocera, 6 Calanoida, 5 Diptera (larvae), 1 Ephemeroptera and 2 Arachnida. Rotifera was the most dominant group and Arachnida the least. No species was dominant; Brachionus falcatus, Asplanchna brightwelli and Tropodiaptomus species were subdominant. Rotifera was also the most abundant group in all stations, followed by Calanoida and Cladocera. Abundance of major groups was higher in wet than dry season, but not significant (P>0.05), except for Diptera that was higher in dry season (P<0.05). Overall community structure exhibited high species diversity and high taxa richness. Total zooplankton, Cyclopoida, Cladocera and Calanoida were negatively correlated with water temperature and water level; and positive with alkalinity, free CO2 andphosphate. The study revealed low pollution indicator species in the reservoir suggestive of moderate water quality.Keywords: Brachionus, Correlation, physico-chemical conditions, Ojirami Reservoir

Meiobenthic Invertebrates Community Associated with Aquatic plant Ceratophyllum demersum Salamiyat irrigation canal / north Baghdad

The aim of the present study is to study the meiobenthic invertebrate's community associated with the aquatic plant Ceratophyllum demersum in Al-Salamiyat irrigation canal / north Baghdad, with the chemical and physical parameters of the canal water, during the study period from September 2015 to May 2016. Two sites were chosen for sample collection, the first site (S1) at the beginning of the canal near it's connection with Tigris river, and the second site (S2) after 10 km from the first site. The chemico-physical analysis results revealed that the water temperature ranged from 10-30oC, and pH values ranged between 6.9-7.8, and the dissolved oxygen concentration and the BOD values from 7.2-9.2 mg/l, and 1.2-5.4 mg/l, respectively. The salinity values were ranged between 0.45 and 0.86 ‰, and the total suspended solids were changed 357-674mg/l. A total of 9089 individuals of meiobethic invertebrates were sorted out from C. demersum during the study perid , representing 34 species including Hydra oligactis (Hydrozoa , Cnidaria); two species of Turbellaria ( Platyhelminthes); five species of Nematoda; seven species of Rotifera; 14 species of aquatic Oligochaeta (Annelida); four Crustacea, and one species of chironomid larva species, in addition to recording one individual of Tardigrada from (S2). The highest total number of meiobenthic invertebrates of 5600 individuals were recorded at (S2), while at (S1) less number of (3489) individuals were reported. Four species were recognized as a new records for Iraqi fauna, including Hydra oligactis (Hydrozoa:Cnidaria); Macrostomum tuba (Platyhelminthes: Turbellaria(, Dero cooperi (Annelida:Oligochaeta,) and Stenocypris hislopi )Crustacea: Otracoda(.

Biodiverse rotifer assemblage (Rotifera: Eurotatoria) of floodplain lakes of the Brahmaputra basin of lower Assam, northeast India: composition and ecosystem diversity

The study aims to ascertain the hypothesis on the rich rotifer biodiversity of the floodplain lakes (beels) of the Brahmaputra river basin and to use these metazoans to assess trophic status or to characterize habitat variations of wetlands. The plankton samples collected from four beels of lower Assam revealed 160 Rotifera species belonging to 35 genera and 19 families. The richness is of biodiversity value as ~38.0% and ~57.0% of the rotifer species known till date from India and northeast India (NEI), respectively. One species each is new to the Oriental region and NEI, and three species are new to Assam; 23 species merit global biogeography interest and several exhibit distribution values in the Indian sub-region. The diverse Lecanidae > Brachionidae > Lepadellidae > Trichocercidae and speciose littoral-periphytic Lecane > Lepadella > Trichocerca, and richness of Brachionus spp. following removal of aquatic macrophytes are noteworthy. Overall rotifer composition showed homogeneity amongst beels while lower monthly richness and community similarities affirmed heterogeneity within individual beels. We propose L/B quotient based on Lecane: Brachionus species ratios to characterize habitat variations of the sampled wetlands. Sladecek’s B/T quotient based on Brachionus: Trichocerca species ratios affirmed general’ meso-trophic’ status of different beels. Our results provided little insight on the influence of individual abiotic factors but the canonical correspondence analyses asserted higher cumulative influence of ten abiotic parameters on Rotifera richness in each beel.

First report of freshwater rotifers (Rotifera: Eurotatoria) from south Andaman, India: Composition and interesting elements

Plankton samples collected from freshwater lentic ecosystems of south Andaman, India, revealed 70 species of Rotifera belonging to 25 genera and 16 families. The reports of Australasian Lecane batillifer, Oriental endemic Lecane bulla diabolica and three Paleotropical species, and 68 new records of Eurotatoria from Andaman and Nicobar Islands contribute to biodiversity and biogeography of the Indian Rotifera. The rotifers are characterized by diverse Lecanidae>Lepadellidae>Brachionidae and common nature of species of “tropic-centered” Lecane and Brachionus. The occurrences of a large number of cosmopolitan species, and several tropicopolitan and pantropical species are notable. This report indicates a further scope for biodiversity update on these metazoans from the insular freshwater of Andaman and Nicobar Islands located in the Andaman Sea.

Species Richness Estimate of Freshwater Rotifers (Animalia:Rotifera) of Western Maharashtra, India with Comments on their Distribution

Of the 2031 Rotifera species described so far, the Oriental region harbours 78 monogonont genera with 486 species and 9 bdelloid genera with 58 species. Only a small fraction (~19%) of that total rotifer diversity is known from the Indian region when compared with the South-east Asian countries.

Meiobenthic Invertebrates Community Associated with Aquatic plant Ceratophyllum demersum Salamiyat irrigation canal / north Baghdad

The aim of the present study is to study the meiobenthic invertebrate's community associated with the aquatic plant Ceratophyllum demersum in Al-Salamiyat irrigation canal / north Baghdad, with the chemical and physical parameters of the canal water, during the study period from September 2015 to May 2016. Two sites were chosen for sample collection, the first site (S1) at the beginning of the canal near it's connection with Tigris river, and the second site (S2) after 10 km from the first site. The chemico-physical analysis results revealed that the water temperature ranged from 10-30oC, and pH values ranged between 6.9-7.8, and the dissolved oxygen concentration and the BOD values from 7.2-9.2 mg/l, and 1.2-5.4 mg/l, respectively. The salinity values were ranged between 0.45 and 0.86 ‰, and the total suspended solids were changed 357-674mg/l. A total of 9089 individuals of meiobethic invertebrates were sorted out from C. demersum during the study perid , representing 34 species including Hydra oligactis (Hydrozoa , Cnidaria); two species of Turbellaria ( Platyhelminthes); five species of Nematoda; seven species of Rotifera; 14 species of aquatic Oligochaeta (Annelida); four Crustacea, and one species of chironomid larva species, in addition to recording one individual of Tardigrada from (S2). The highest total number of meiobenthic invertebrates of 5600 individuals were recorded at (S2), while at (S1) less number of (3489) individuals were reported. Four species were recognized as a new records for Iraqi fauna, including Hydra oligactis (Hydrozoa:Cnidaria); Macrostomum tuba (Platyhelminthes: Turbellaria(, Dero cooperi (Annelida:Oligochaeta,) and Stenocypris hislopi )Crustacea: Otracoda(.

ПЛАНКТОННАЯ ФАУНА МАЛЫХ ОЗЕР ВЕРХНЕАМУРСКОГО БАССЕЙНА

Small lakes are a special type of habitat with characteristic specific conditions. Due to the multiplicity and characteristics diversity of the ecological capacity small water bodies are less studied than larger lakes. In order for biodiversity conservation was inventoried of plankton invertebrates in the small lakes of the Upper Amur basin. 136 species and subspecies belonging to 69 genera, 32 families, 10 orders are noted in zooplankton. Rotifera species list contains 73 taxa, Cladocera – 35, Copepoda – 27 and Anostraca – 1. Families Brachionidae, Trichocercidae, Synchaetidae, Euchlanidae, Daphniidae, Chydoridae, Diaptomidae, Cyclopidae have the highest number of species. Plankton fauna of small lakes is highly species-specific.

VARIATION IN ZOOPLANKTON DIVERSITY AND ITS RELATIONSHIP WITH ABIOTIC ENVIRONMENT OF A VANDIYUR POND TAMILNADU INDIA

Ponds, Lakes and Reservoir are most significant water resources with multiple human utilization andecological relevance in which Zooplankton diversity is one of the most important ecological parameters in water quality assessment. It is good indicator of the changes in water quality because they are strongly affected by environmental conditions. In the present study an attempt has been made to study the seasonal variations in the Zooplankton community, its diversity and hydrological parameters of this water body. In the present study, a total of 24 species of Zooplankton were indentified from different classes during August2014 to January 2015. Among the identified species, Zooplankton showed the complete dominance, especially, zooplankton belonging to four major groups i.e. 9 species of Rotifera, 6 species each of Cladocera, 4 Copepoda and five species of Ostracoda.

The occurrence of the new zooplankton species in the Lena river delta

The Lena River impact on the water bodies of its catchment area increases in connection of climate warming. During spring floods the river water enters the numerous floodplain water basins, further promotes the passive dispersal of their fauna in the northern direction. The occurrences of new (for the local fauna) zooplankton species repeatedly documented in the lakes on Samoylov Island in the south part of the Lena Delta over the last 15 years. Seven “invasive species” belong to Cladocera, four to Copepoda and one species of Rotifera. Some cladocerans –Sida crystallina (O.F. Muller, 1776), Limnosida frontosa (Sars, 1862), Diaphanasoma brachyurum (Lievin, 1848) and Polyphemus pediculus (Linnaeus, 1761) – several times appeared and disappeared in the floodplain aquatic habitats on Samoilovsky Island during the observation period. Simocephalus vetulus (O.F. Muller, 1776) found conditions here to be favorable and formed the local population in the floodplain pools. Acroperus harpae (Baird, 1834) and Holopedium gibberum Zaddach, 1855 started to settle from low floodplain in neighboring water ecosystems of the first delta terrace with a height of 10–16 m. The spread of resting stages of zooplankton are likely to occur with the participation of waterfowl. In years with extremely high spring tide, the expansion of species, not typical for the area, was of a catastrophic nature. A massive invasion of certain species, for example Holopedium gibberum Zaddach, 1855, can cause a rapid restructuring of the lake biocoenosis and disturb the ecological balance in it, resulting in parasitic epizootic.

Sensitivity of plankton indices to lake trophic conditions.

Herein, we report the response of indices based on phytoplankton and zooplankton and their combination to different nutrient concentrations in lakes. The study was carried out in ten lakes in northeastern Poland. Integrated samples were collected from the epilimnion during the summer of 2012–2013. Secchi disk visibility (SD), total phosphorus (TP), total nitrogen (TN), and chlorophyll a were used as proxies for eutrophication. We calculated 16 plankton indices: two phytoplankton indices, six crustacean indices, five rotiferan indices, two zooplankton diversity indices, and one combined phytoplankton and zooplankton index. Among them, nine indices with the strongest correlations with TP were selected: percentage share of Crustacean species indicative of high trophy in the indicative group’s numbers (IHTCRU), percentage share of Rotifera species indicative of high trophy in the indicative group’s numbers IHTROT, Crustacean ratio of biomass to numbers B/NCRU, phytoplankton trophic index (TITP+TN), Margalef’s index, percentage share of cyclopoid biomass in total biomass of Crustacea (CB), Rotifera numbers (NROT), biomass of Cyclopoida (BCY), and ratio of the cyclopoid biomass to the biomass of Cladocera (CY/CL). The sensitivity of the normalized values of these indices to proxies of eutrophication was tested. IHTCRU, IHTROT, and B/NCRU were the most sensitive and gave the strongest responses at lower TP concentrations (<35 μg/L). The phytoplankton trophic index, TITP+TN, together with the zooplankton-based Margalef’s index and CB were very sensitive in both low (<35 μg/L) and high (>60 μg/L) TP conditions. On the other hand, NROT, BCY, and CY/CL were slightly sensitive at low TP concentrations while their reaction was notable at high TP concentrations. A similar pattern of response was observed for TN concentration and SD visibility.

Influence of inlet water on the biotic and abiotic variables in a fish pond.

The effects of treated and untreated water inlets with macrophytes on the improvement of water quality and zooplankton community were evaluated in a fish pond with continuous water flow. Water and zooplankton samples were retrieved at four sites during nine months. There were differences (p<0.01) between inlet water from fish pond and inlet water from canal with macrophytes, featuring higher concentrations of nutrient load, mainly TAN and TP in the former. The inlet water from fish pond contained a higher number of abundant species (9 species), whilst the water supply from the canal with macrophytes had a greater richness (31 species) of zooplankton species. Results showed that inlet water without macrophytes directly affected the characteristics of the water column and the dominance of zooplankton species such as Thermocyclops decipiens, and greater abundance of Rotifera species. Since aquatic plants in the inlet water of fish pond analyzed showed lower allochthonous material loads from the previous fish pond, the management adopted with macrophytes may be applied to avoid eutrophication risks, common in farm ponds.