Correlation of Limnological Features with Ichthyofauna in Hatnur Reservoir in Jalgaon, Maharashtra, India

Background: Limnologycovers the study of all inland waters including running and standing waters, fresh and saline, natural or man-made reservoirs. Unplanned urbanization, rapid industrialization and indiscriminate use of artificial chemicals lead to heavy and varied pollution in aquatic environments causing to deterioration of Limnological features and depletion of aquatic fauna including fish. Scarcity of research related to limnological features and ichthyofauna diversity in Hatnur reservoir stimulated to undertake the present work. Methods: River Tapi (or Tapti) is arising in Madhya Pradesh and flows westward between two spurs of the Satpuda Rangeacross Maharashtra state, and through Gujarat state to the Gulf of Khambhat. Hatnur reservoir (750 90扙, 210 12扤) formed due to an earth-fill dam on Tapi river near Hatnur village in Jalgaon district of Maharashtra state. Water quality parameters were assessed using standard methods described by APHA and fish diversity was evaluated in the Hatnur reservoir. Results: Seasonal fluctuations in water quality parameters and their relationship with ichthyofauna inhabiting the Hatnur reservoir were assessed. The results obtained in the present study indicated that physicochemical properties of water samples collected from the Hatnur reservoir were within recommended limits of the Bureau of Indian Standards (BIS). Conclusion: It is concluded that water in Dam was less polluted, suitable for agricultural and domestic use and suitable to inhabit the fish diversity. Future studies should focus on under-explored and unexplored areas of the Tapi riverine system in North Maharashtra to comprehensively document the fish diversity.

Zooplankton diversity of Chikkadevarayana canal in relation to physico-chemical characteristics.

Plankton diversity and physico-chemical parameters are an important criterion for evaluating the suitability of water for irrigation and drinking purposes. In this study, we tried to assess zooplankton species richness, diversity and evenness to predict the state of Chickadevarayana canal water of Cauvery River according to physico-chemical parameters. A total of 51 taxa were recorded with 22 rotifers, 5 copepods, 6 cladocerans, 1 ostracoda and 17protozoans. More number of zooplankton species were recorded in Darasaguppe (30) followed by Edmuri (26), Kennala (20), Pandavpura (19) and Gendehosahalli (16). Among the rotifers, Euchlanis sp. species was abundant (194). Acantholeberis curvirostris was predominant among cladocerans (970). Among copepods, numerical superiorities were found in the case Cyclops sp. Cypris sp. was recorded in the ostracoda. Centropyxis aculeate repeated abundance in protozoans (412). The water samples analyzed for temperature, pH, electrical conductivity, alkalinity, hardness, dissolved oxygen, phosphate, sulphate and nitrate did not indicate variation. The occurrence of Asplanchna herricki, Lacrymaria sp, Brachionus pala and Monostyla lunaris showed highest similarity of occurrence reaching above 90%. The study revealed that the presence of certain species like Monostyla, Lepadella, Leydigia, Keratella, Branchionus and Cypris species can be considered as a biological indicator for eutrophication.

Physico-chemical properties and ichthyofauna diversity in Karala River, A Tributary of Teesta River at Jalpaiguri District of West Bengal, India.

The present investigation was carried out on the Karalla River, a tributary of the river Teesta from February, 2009 to July, 2010 at three stations to study the seasonal change of physico-chemical factors and ichthyofaunal diversity. The constituents monitored included air and water temperature, turbidity, pH, total dissolved solid, total suspended solid, total solid, depth, conductivity, dissolved oxygen, biological oxygen demand, free carbon dioxide, chloride, salinity, total alkalinity, hardness, nitrate, phosphate and silicate. Through out the study period the water was hard and a significant variation of the rest parameters was observed. In respect of Ichthyofauna diversity, a total of fifty five species belonging to eight orders and twenty families were identified. Among the 55 species, thirty one species were found under the order Cypriniformes, ten species were found under the order Perciformes, seven species were found under the order Siluriformes, three species were found under the order Synbranchiformes and a single species was found under the order Osteoglossiformes, Anguilliformes, Beloniformes and Tetraodontiformes each. This observation indicates that Cypriniformes order is the most dominating of all other seven important orders. There are thirty three species which were common to all the three sampling stations and hence can be considered as migratory ichthyofauna. In this lotic system the diversity and distribution of fishes were uneven. The un-even distribution and diversity may be due to physico-chemical factors of water, substratum soil quality, and unscientific fish capture technology. The increase in species richness at down streams (SII and SIII) also may be due to the occurrence of submerged weeds.

Variations in physico-chemical and microbiological characteristics of water during breeding of Cyprinus carpio in a closed hatchery system.

Physico-chemical and microbial characteristics of culture water were examined during the induced breeding of Cyprinus carpio in a controlled environmental system. Water temperature, dissolved oxygen, nitrate, phosphate, pH, ammonia nitrogen, total bacterial count, hardness, salinity, carbonate and bicarbonate were estimated before and after spawning and hatching. Average alteration in water pH before and after spawning was 7.91-7.57 and 7.86-7.58 respectively. Total hardness, carbonate and bicarbonate showed insignificant variations. Nitrate, ammonia nitrogen and phosphate contents significantly increased after spawning and hatching p<0.05. The average increase in nitrate was from 2.94 to 8.62 /g l-1 after spawning and 3.10 to 8.49 /g l-1 after hatching. Ammonia nitrogen contents were sharply increased from an average of 0.011 to 1.87 mg l-1 after spawning and 0.013 to 0.56 mg l-1 after hatching. The average phosphates increased from 2.59 to 4.15 /g l-1 after spawning and 2.61 to 4.03 /g l-1after hatching. Dissolved oxygen was sharply depleted even after a continuous aeration. Temperature played a vital role during breeding. No successful breeding was observed at a temperature of 17oC or below and 31oC or above. There is a significant association between temperature, spawning and hatching (p<0.05). By optimizing temperature, the breeding success of this carp was achieved with a statistical significance of p<0.05. Total bacterial count was significantly increased after spawning and hatching. It was related to the amount of discharge and may cause mass mortality of fish embryo and spawn in a closed hatchery system.

Zooplankton assemblage of Oyun Reservoir, Offa, Nigeria

The influence of physico-chemical properties of Oyun Reservoir, Offa, Nigeria (a shallow tropical African reservoir) on its zooplankton composition and abundance were investigated at three stations for two years between January 2002 and December 2003. Diversity is not high: only three groups of zooplankton were found: Rotifera with eight genera; and Cladocera and Copepoda with three genera each. Rotifera dominated numerically (71.02%), followed by Cladocera (16.45%) and Copepoda (12.53%). The zooplankton was more prevalent during the rainy season, and there were variations in the composition and abundance along the reservoir continuum. Factors such as temperature, nutrients, food availability, shape and hydrodynamics of the reservoir, as well as reproductive strategies of the organisms, strongly influence the generic composition and population density of zooplankton. Prevention of ecological deterioration of the water body would greatly should result in a more productive water body, rich in zooplankton and with better fisheries. Rev. Biol. Trop. 57 (4): 1027-1047. Epub 2009 December 01.

La influencia de las propiedades fisicoquímicas del Reservorio Oyun, Offa, Nigeria (un embalse tropical somero) sobre la composición y abundancia del zooplancton fue investigada en tres estaciones entre enero de 2002 y diciembre de 2003. La diversidad no resultó muy alta con tres grupos de zooplancton: Rotifera con ocho géneros, y Cladocera y Copepoda con tres géneros cada uno. Rotifera dominó (71.02%), seguido de Cladocera (16.45%) y Copepoda (12.53%). El zooplancton fue más común durante la temporada de lluvias, y hubo variaciones en su composición y abundancia a lo largo del embalse. Factores tales como la temperatura, los nutrientes, la disponibilidad de alimentos, la forma y la hidrodinámica del embalse, así como las estrategias reproductivas de los organismos, influyen fuertemente en la composición genérica y la densidad poblacional del zooplancton. La prevención del deterioro ecológico de esta masa de agua, resultaría en un cuerpo de agua más productivo, rico en zooplancton y con mejor pesca.