Effect of climato-environmental parameters on chlorophyll a concentration in the lower Ganga basin, India / Efecto de los parámetros climáticos ambientales sobre la concentración de clorofila a en la cuenca baja del Ganges, India

Introduction: Chlorophyll a concentration proxies the phytoplankton biomass which directly involves in signifying the production functions of aquatic ecosystem. Thus, it is imperative to understand their spatio-temporal kinetics in lotic environment with reference to regional climatic variabilities in the tropical inland waters. Objective: In-situ studies were conducted to examine the changes in phytoplankton biomass in lower Ganga basin as influenced by various environmental parameters under regional climatic variability during 2014-2016. Methods: Firstly, the most key influential environmental parameters on riverine Chl-a concentration were determined. Then the direct cascading effect of changing climatic variables on key environmental parameters were derived through modeling and quantified probable changes in mean Chl-a concentration in the lower stretch of river. Results: Only five environmental parameters namely water temperature, total dissolved solid, salinity, total alkalinity and pH were key factors influencing Chl-a (Multiple R2: 0.638, P < 0.05). Present estimates indicate that if the present rate of regional climatic variability over the last 3 decades (mean air temperature + 0.24 °C, total annual rainfall -196.3 mm) remain consistent over the next three decades (2015-2045), an increase in mean Chl-a by + 170 µgL-1 may likely be expected grossly reaching about 475.94 µg L-1 by the year 2045 or more. Conclusions: The present study is first such comprehending a gross hint towards the probable ecosystem response with an alternative model based methodology in data-deficient situations. Subsequently, the output would also be of great benefit for increase water governance and developing strategy protocol for sustainable water management for greater ecosystem services.

Introducción: La concentración de clorofila a representa la biomasa de fitoplancton la cual influye directamente en las funciones de producción de los ecosistemas acuáticos. Por lo tanto, es imperativo comprender su cinética espacio-temporal en el ambiente lótico con respecto a las variabilidades climáticas regionales en las aguas continentales tropicales. Objetivo: Se realizaron estudios in situ para examinar la influencia de varios parámetros ambientales en la biomasa del fitoplancton en la cuenca baja del Ganges durante 2014-2016. Métodos: En primer lugar, se determinaron los parámetros ambientales más influyentes en la concentración de Chl-a fluvial. Luego, el efecto directo en cascada de las variables climáticas sobre los parámetros ambientales clave, mediante el modelado y los cambios en la concentración media de Chl-a en el tramo inferior del río. Resultados: Solo cinco parámetros ambientales, entre ellos, temperatura del agua, sólidos disueltos totales, salinidad, alcalinidad total y pH, fueron factores clave que influyeron en la Chl-a (R2 múltiple: 0.638, P < 0.05). Las estimaciones actuales indican que si la tasa actual de variabilidad climática regional durante las últimas 3 décadas (temperatura media del aire + 0.24 °C, precipitación total anual -196.3 mm) permanece constante durante las próximas tres décadas (2015-2045), se presente un aumento en el promedio de la Chl-a en +170 µgL-1 y alcance aproximadamente 475.94 µgL-1 para el 2045 o más. Conclusiones: Este estudio presenta una metodología basada en modelos alternativos en situaciones de escasez de datos, la información generada también podría contribuir a mejorar la gobernanza del agua y a desarrollar un protocolo para la gestión sostenible del agua y de esta manera mejorar los servicios ecosistémicos.

Using otolith weight to predict the age of different stocks of Sperata aor (Siluriformes: Bagridae) from the River Ganga

Estimation of accurate fish age is considered as an essential step for the understanding of life history characteristics, population dynamics, and the management of the fisheries resources. The otolith weight keeps on increasing because of continuous deposition of material on the otolith surface; therefore, otolith measurements are successfully used to infer fish age. The present study was conducted to estimate the relationship between otolith weight and observed age (estimated by counting annuli on the sectioned otoliths) for the stocks of Sperata aor. A total of 315 samples were collected from January 2016 to April 2017 from three different stocks of S. aor i.e. Narora-Kanpur, Varanasi and Bhagalpur from the River Ganga. Linear regression analysis was applied between otolith weight and observed age to predict the age of the fish of each stock from otolith weight. Significant relationships between otolith weight and fish age were observed for the three stocks of the selected fish species from the River Ganga (R2 > 0.9, P 0.05). Overall, 88.5, 88.8, and 87.2 % of the predicted ages were correctly classified to their observed ages for Narora-Kanpur, Varanasi, and Bhagalpur stock, respectively. Thus, it can be concluded that the relationship between otolith weight and fish age can provide a surrogate method of age estimation, and can be used to examine the age structure of the three stocks of S. aor from the River Ganga.

La estimación precisa de la edad de peces es considerada un paso esencial para la evaluación de su historia natural, dinámica de población y manejo de pesquerías. El otolito sigue creciendo debido a la continua deposición de material en la superficie; por lo tanto, las medidas del otolito son un buen indicador para inferir la edad del pez. En este estudio se evaluó la relación entre el peso de los otolitos y la edad observada (estimada contando los anillos de los otolitos seleccionados) de individuos de Sperata aor. En total se recolectaron 315 muestras entre enero 2016 y abril 2017 en tres zonas de S. aor en el Río Ganga (Narora-Kanpur, Varanasi y Bhagalpur). Se aplicó un análisis de regresión lineal entre el peso de los otolitos y la edad observada para predecir la edad de los peces de cada zona a partir del peso de los otolitos. Se observaron relaciones significativas entre el peso de los otolitos y la edad de los peces de las zonas del Río Ganga (R2 > 0.9, P 0.05). En general, 88.5, 88.8 y 87.2% de las edades predichas se clasificaron correctamente con respecto a las edades observadas para Narora-Kanpur, Varanasi y Bhagalpur, respectivamente. Se puede concluir que la relación entre el peso de los otolitos y la edad de los peces puede proveer un método para la estimación de la edad y puede ser usado para examinar la estructura de edades en tres stocks de S. aor en el Río Ganga.

The Ganges basin fish Cirrhinus mrigala (Cypriniformes: Cyprinidae): detection of wild populations stock structure with landmark morphometry

Cirrhinus mrigala (Hamilton, 1822) is an Indian major carp originally inhabitant of the Ganga river system in Northern India. No information is available on morphometric variation in natural populations of C. mrigala from Ganga river basin. Therefore, to promote management optimization, this study was undertaken to evaluate the population structure on landmark-based morphometric variations of this commercially important species in Ganges. A total of 381 fish samples of C. mrigala were collected from 10 locations of 10 rivers belonging to Ganges basin. A 12-landmark truss network system was used to generate 66 morphometric variables were transformed (standard length was excluded from the final analysis retaining 65 variables). Transformed measurements were employed to univariate analysis of variance, principal component analysis (PCA) and discriminant function analysis (DFA). Univariate analysis of variance showed significant differences in all the 65 transformed morphometric characters studied. Eight principal components were extracted from 65 significant characters accounting for 94.1 % of the variation. Forward stepwise discriminant function analysis of the 65 significant variables produced eight discriminating variables. DFA extracted eight discriminating functions contributed overall to the variance. The first discriminant function (DF) accounted for 37.9 % while second DF accounted for 23.5% of the among-group variability. In DFA, 45.7 % original while 39.1 % of cross-validated grouped cases were correctly classified in the overall assignment of individuals, indicating low distinction among the stocks of all the species i.e. low isolation of the stocks for the morphometric measurements. Common ancestry in the prehistoric period and migration of individuals between the rivers could be the possible reason for the observed low level of morphometric differentiation among wild mrigal populations. In future, the application of molecular genetic markers along with morphometric studies would be an effective method to examine the genetic component of phenotypic relatedness between geographic regions and to facilitate the development of management recommendations.

Cirrhinus mrigala es una carpa originaria del sistema fluvial del río Ganges al norte de India, de cual no hay información sobre la variación morfométrica de sus poblaciones naturales en esta cuenca. Por lo tanto, para promover la optimización de su manejo, se evaluó la estructura poblacional usando morfometría basada en puntos de referencia de C. mrigala. En total se midieron 381 individuos de C. mrigala, recolectados en 10 puntos de 10 ríos de la cuenca del Ganges. Se utilizaron 12-puntos de referencia de sistema de redes truss para generar 66 variables morfométricas, de donde se excluyó la longitud estándar y se utilizaron 65 variables. Las medidas transformadas se utilizaron para un análisis de varianza univariado, análisis de componentes principales y análisis de función discriminante. El análisis de varianza mostró diferencias en todos los 65 caracteres morfométricos estudiados. Se extrajeron ocho componentes principales de los 65 caracteres, que suman el 94.1 % de la variación. El análisis de función discriminante de las 65 variables produjo ocho variables discriminantes que contribuyeron en la varianza a nivel general. La primera función discriminante representó 37.9 %, mientras que la segunda 23.5 % de la variación entre grupos. En el análisis de función discriminante, 39.1 % de lo agrupado por validación cruzada fue correctamente clasificado en la asignación general de individuos, lo que indica baja diferenciación entre las poblaciones, lo que puede ser un bajo aislamiento de las poblaciones para las medidas morfométricas. Otra posible razón para la baja diferenciación morfométrica es la existencia de un ancestro común en el periodo prehistórico y la migración de individuos entre ríos. En el futuro, la aplicación de marcadores genéticos moleculares junto con estudios morfométricos será un método efectivo para examinar el componente genético de la relación fenotípica entre áreas geográficas y facilitar el desarrollo de recomendaciones de manejo.

The Physiochemical, Biological Quality and Seasonal Variability of River Ganges in Varanasi, Uttar Pradesh, India

Background: The Ganga River is a life-line, a symbol of purity and virtue for countless people of India. Nearly all the sewage, industrial effluent, runoff from chemical fertilizers and pesticides used in agriculture within the basin, and large quantities of solid waste, including thousands of animals carcasses and hundreds of human corpses are dumped in the river everyday which posed a considerable public health threat to the religious bathers and a large number of people living along the river who uses Ganges water for drinking and other household purposes. Objective: To assess the physiochemical and biological quality of river Ganges water and to study the seasonality pattern of pollution of River Ganges. Materials and Methods: Two points namely Samne ghat and Rajghat (entry and exit point of Ganga into the city) were selected as the first and the last sampling stations, beside 8 other intermediate sampling stations to assess the physiochemical and biological quality of River Ganga water. The study was conducted from April 2013 to March 2014 and this period was crudely divided into three seasons viz Winter, Summer and Rainy season for the purpose of studying seasonality pattern of pollution. Results: As the river progress through city of Varanasi, Total dissolved solids (TDS), Chloride, Conductivity, Biochemical Oxygen Demand (BOD), Nitrate, Nitrite and Most Probable Number (MPN) increases, DO decreases progressively and Temperature and pH remain same. Conclusion: As far as quality of water with regard to recreational and industrial purposes are concerned, Ganges water may be considered useful but most of the parameters observed across different seasons indicates that it may not be used as potable water.

Assessment of pollution of river Ganges by tannery effluents using genotoxicity biomarkers in murrel fish, Channa punctatus (Bloch).

River pollution due to rapid industrialization and anthropogenic activities adversely affects the aquatic organisms, especially fish. Here, we assessed the genotoxicity, mutagenicity and bioaccumulative aspects of tannery effluents in freshwater murrel, Channa punctatus, an inhabitant of river Gange. Test specimens were collected from three different polluted sites of the river within and nearby Kanpur area during different seasons and blood samples of these specimens were processed for comet assay and micronucleus test as genotoxicity biomarkers. A significantly (P <0.05) higher micronuclei induction, nuclear abnormalities and % tail DNA was observed in the specimens collected from the polluted sites. Bioaccumulation studies in the muscle (1.202 µg/g) and gill tissues (<0.300 µg/g) of the specimens revealed the concentration of chromium (core component of tanning industry) above the maximum permissible limits as prescribed by World Health Organization (WHO). The findings of the present analysis indicated contamination of river Ganges with tannery effluents which induce genotoxicity in fish with seasonal variation.

Assessment of Leachate Pollution Index and Greenhouse Gas Emission at MSW Dumpsites along Ganga River at Varanasi, India.

Recent scientific attention has shown serious concern towards municipal solid wastes (MSW) as a source of greenhouse gases and concentrated leachate. We studied the leachate pollution index (LPI) and emission fluxes of two greenhouse gases (CH4 and CO2) at two municipal solid waste dumpsites situated along the Ganga River at Varanasi (India). The LPI is a quantitative tool by which the leachate pollution data of dumping sites can be reported uniformly. Concentration of nutrient ions (Ca2+, Mg2+, Na+, K+, NO3 -, Cl-, PO4 3- ) and heavy metals (Cd2+, Fe2+, Cu2+, Pb2+, Ni2+ ,Zn2+, Co2+, Mn2+ ) in leachate varied with season with values being highest in rainy season. Total dissolved solids, conductivity and salinity in leachate showed a similar trend. Leachate pollution index was found to be 87.19 and 82.56 at KZP and BPS sites respectively. The LPI was much higher than the permissible limit at both the sites indicating high contamination potential for surface and ground water and risk to human health. Among all the study metals, Pb was found in abundance at Site 1. The emission flux of CH4 ranged from 10.73 to 96.74 mg m-2 h-1 and that of CO2 from 17.28 to 321.89 mg m-2 h-1. Emission flux of both the greenhouse gases increased with rising moisture and temperature. The rates were higher at young landfill site and between-site differences in the emission of CH4 and CO2 were significant. The study has relevance establishing landfill associated contamination to Ganga River and reducing uncertainties in greenhouse gas emission estimates in India.

Age and growth in the Indian major carp Labeo rohita Cypriniformes: Cyprinidae from tropical rivers of Ganga basin, India / Edad y crecimiento de la carpa mayor de la India Labeo rohita Cypriniformes: Cyprinidae de los ríos tropicales de la cuenca Ganga, India

Labeo rohita is a member of the Indian major carp species and originally an inhabitant of the Ganga river network in India. It is among the top ten aquaculture species of the world. Since there is a lack of information on the growth pattern of the wild populations of this species, this study aimed at evaluating the pattern of age and growth, to support the development of effective management plans. A total of 1 082 samples of L. rohita were obtained from May 2009 to July 2012 in six drainages of the Ganga basin. Scales of the fish were used to determine the age and growth by analyzing the annual rings growth. Out of six populations, a maximum 8 age classes were recorded from two rivers Betwa and Sharda. The back-calculated lengths at 8 age class ranged from 86.22cm to 91.66cm. However, for the rest of rivers up to 7 age classes were recorded. Among growth parameters, specific rate of length increase Cl and specific rate of weight increase Cw showed decreasing trend, and three distinct life stages of L. rohita were recorded based on growth constant data Clt. Analysis of variance ANOVA of the back-calculated length data set of six populations indicated a significant difference p0.05. All three populations showed significant variation in length attainment during 1 and 3 age groups, while two populations showed significant variation in length attainment during the 2 and 7 age classes. Additionally, analysis of age frequency at different length intervals indicated that with increase in age class, number of fish samples was reduced. Since the pattern of life history traits of L. rohita have not been attempted in the recent past; therefore, this study will guide fisheries biologists about the current stock structure of this fish across different spatial scale of the Ganga basin.

Labeo rohita es de las principales especies de carpas hindúes y originalmente un habitante de la red del río Ganges en la India. Se encuentra en la lista de las diez especies principales de la acuacultura mundial. Puesto que no hay información sobre el patrón de crecimiento de las poblaciones silvestres de esta especie, este estudio tuvo como objetivo evaluar el patrón de edad y crecimiento para apoyar el desarrollo de planes de gestión eficaces. Un total de 1 082 muestras de L. rohita se obtuvieron en el periodo de mayo 2009 a Julio 2012, en seis desembocaduras de la cuenca del río Ganges. Las mediciones de los peces fueron utilizadas para determinar la edad y el crecimiento mediante el análisis de los anillos de crecimiento anuales. De las seis poblaciones, se registró un máximo de categoría de edad 8 en dos ríos Betwa y Sharda. Las longitudes de retrocálculo en la edad 8 variaron entre 86.22-91.66cm. De los parámetros de crecimiento, la tasa específica de aumento de longitud Cl y la tasa específica de aumento de peso Cw mostraron una tendencia decreciente, y basado en los datos constantes de crecimiento Clt se registraron distintas fases del ciclo de vida de L. rohita. El análisis de variancia ANOVA de los datos de longitud de retrocálculo de seis poblaciones indicó una diferencia significativa p0.05. Las tres poblaciones mostraron una variación significativa en la obtención de la longitud durante los grupos de edad 1 y 3, mientras que dos poblaciones mostraron una variación significativa en lograr la longitud durante los tipos de edades 2 y 7. Además, el análisis de la frecuencia de la edad en diferentes intervalos de longitude indicó que, con el aumento de la categoría de la edad, se redujo el número de muestras de peces. Dado que el patrón de rasgos de la historia de la vida de L. rohita no se ha tratado en el pasado reciente, este estudio será una guía para los biológos de peces acerca de la actual estructura de la población de estos peces en diferentes escalas espaciales de la cuenca del Ganges.

Analysis of water quality parameters of River Ganga during Maha Kumbha, Haridwar, India.

This study represents the summary of the water quality of River Ganga during mass bathing in Haridwar during Maha Kumbha of 2010 in terms of microbiological and molecular analysis. The sample was collected from River Ganga during Makar Sankranti to Shakh Poornima and assessed for fecal indicator bacteria Escherichia coli along with Standard Plate Count (SPC) to determine total bacterial load in the river. Of all the nine days of sample collection (mass bathing days) results on the main royal bath (Baisakhi) displayed maximum SPC (log 6.79 cfu ml-1) and most probable number (210 and 150 MPN 100 ml-1 for total and fecal coli form, respectively). The water was extremely contaminated and not suitable for drinking on Somvati Amavasya, Maghi Poornima, Maha Shivratri and Baisakhi. The results clearly indicated that the mass bathing coupled with ritual activities performed by bathers was most probable cause of increased values of different parameters. The polymerase chain reaction analysis targeting malate dehydrogenase (mdh) gene proved to be more rapid and sensitive than classical culture techniques.

Studies on chemical composition and energy transformation in river Ganga at Kanpur and Varanasi due to environmental degradation.

Impact of effluents discharged in Ganga through various sources on chemical composition, energy transformation rate and level of heavy metals was studied at Kanpur and Varanasi. The effluents were found to be nil in oxygen with acidic in oxygen with acidic to neutral pH (6.8-7.0) and having very high values of free CO2 (40-68 mg l-1), alkalinity (300.0-412.0 mg l-1), conductance (1082.0-1824.0 μmhos), total dissolved solids (542.0-912.0 mg l-1), hardness (228.0-330.0 mg l-1), chloride (42.0-60.0 mg l-1), organic matter (8.4-18.2 mg l-1) and BOD load (98.0-248.0 mg l-1). The heavy metals Cu, Cr, Cd, Pb and Zn were also quite high in the effluents (48.6-78.4, 54.0-84.6, 9.8-12.4, 72.4-84.0 and 148.6-284.0 μg l-1 respectively). The discharged effluents induced severe reduction in oxygen (av. 0.82-3.4 mg l-1) and sharp increase in the level of free CO2 (av. 10.8-24.8 mg l-1), alkalinity (182.4-288.4 mg l-1), conductance (480.0- 628.0 mmhos), total dissolved solids (254.0-315.0 mg l-1), hardness (170.0-259.0 mg l-1), chloride (36.0-52.0 mg l-1), organic matter (4.8-6.8 mg l-1) and BOD load (36.4- 58.4 mg l-1) at the discharge point (OF zones) from their comparatively much lower values before discharge (AOF zone). The rate of energy transformation and photosynthetic efficiency also reduced considerably at the discharge point (av. 1060-2101 calm-2day-1 and 0.09-0.18%) from high values before discharged point (av. 4045-4733 calm-2day-1 and 0.34-0.42%). The level of Cu, Cr, Cd, Pb and Zn also showed higher values at the discharged point (20.4-38.0, 22.4-54.8, 5.2-7.8, 30.8-72.0 and 64.8-120.8 μg l-1 respectively). Considerable improvement was observed below the discharge (BOF zone). Comparison with earlier observation revealed that the magnitude of impact has reduced considerably after the regulation in the discharge both in he respect of chemical composition and energy transformation rates.

Use of RAPD fingerprinting for delineating populations of hilsa shad Tenualosa ilisha (Hamilton, 1822)

RAPD was used to delineate the hilsa populations sampled from the Ganga, Yamuna, Hooghly, and Narmada Rivers at six different locations. Six degenerate primers were used to generate the fragment patterns from the samples collected. All primers were highly polymorphic and generated high numbers of amplification products. Nei's genetic distances were calculated between locations. The overall average genetic distance among all the six locations was 0.295. The Fst value within the Ganga was 0.469 and within the Hooghly it was 0.546. The overall Fst value for the six populations analyzed was 0.590. The UPGMA dendrogram clustered the hilsa into two distinct clusters: Ganga and Yamuna populations and the Hooghly and Narmada populations.