Abstract

Polluted water not only affects the life of present generation but it also affect the life of upcoming generations because its effect remains for long. The aim of the present investigation was to study the pollution bioindicators of the River Ghaggar with special reference to phytoplankton.The study of the plankton with reference to the pollution bioindicators species and variations revealed that they could indicate the water quality.Phytoplankton population was composed of 4 major groups of algae namely Cyanophyceae (blue green algae), Chlorophyceae (green algae), Bacillariophyceae (diatoms) and Euglenophyceae in water ecosystem. At both the sites (S1, S2) a total of 35 genera of phytoplankton were recorded belonging to 4 major classes. Among these Bacillariophyceae with 20 genera were found to be dominant followed by Chlorophyceae with 7 genera, Cyanophyceae with 4 genera and Euglenophyceae with 3 genera during the study period. The study also shows that the species like Nitzschia palea, Synedra ulna, Euglena acus, Fragilaria sp., Oscillatoria sp., Gomphonema sp. Meridion sp., was present throughout the study period and they are the indicator of bad water quality. Phytoplankton population showed high diversity in the summer and low in monsoon period. Various diversity indices (Shannon-Wiener diversity index, Simpson’s diversity index and Pielou evenness index) were used to found the seasonal variation of phytoplankton. The Shannon- Wiener diversity index was most useful in indicating the trophic status of the water as well as the pollution status, which in this case, depicted a moderate level of pollution in River.

1. Introduction

At present the Ghaggar is an inland and largely a seasonal stream as neither the master stream nor any of its feeders take their rise in the snow covered region of the Himalayas. Ghaggar, one of the major rivers of northern India originates from outer Himalayas. It runs along the foot of the Shiwalik and flows about 200 miles (320 km) southwest through Haryana state and Punjab to Rajasthan and then disappear itself in the sands of the great Indian Thar Desert. Its seasonal water flow is dependent on monsoon (seasonal) rain fall. It receives domestic, industrial and municipal waste water effluents all along its course ¹. Phytoplankton is microscopic unicellular aquatic plants and they convert solar radient energy into biological energy through photosynthesis. This energy is transferred to higher organisms through food chain ^{2, 3}. Phytoplankton are highly diverse group of photoautotrophic organisms with chlorophyll-a and unicellular reproductive structures, which are important for aquatic habitats ^{4, 5}. They are important primary producers in the base of the food chain, constitute a vital link and an important biological indicator of the water quality ⁶. Thus, study of phytoplankton is very useful tool for the assessment of water quality in any type of water body and also contributes to the understanding of basic nature and general economy of the lake ⁷. Phytoplankton is the primary producer community and consists mainly of algae such as diatoms, dinoflagellates and a variety of forms from other divisions of the plant kingdom. These are very sensitive to the environment they live in and any alteration in the environment leads to the change in their communities in terms of tolerance, abundance, diversity and dominance in the habitat ⁸. Water maintains an ecological balance between various group of living organism and their environment ¹⁹. Phytoplankton study provides a relevant and convenient point of focus for research on the mechanism of eutrophication and its adverse impact on aquatic ecosystem ¹¹.

Hence, monitoring of aquatic ecosystems from phytoplankton study point of view is very important to initiate conservation and management programs. This study provides fundamental information on the phytoplankton species diversity, abundance and the influence of pollution on phytoplankton population in River Ghaggar in Punjab.

2. Materials and Methods

The base flow generated in the river system is utilized at various points for various purposes like drinking, irrigation and industrial. The study area is located in south-eastern part of Punjab. S1 of river Ghaggar is village Devigarh in Bhuner Heri in Patiala. It is located 21 kilometers toward south from district headquarters, Patiala. It is76 kilometers from state capital Chandigarh .The area lies between latitudes 29º 47´ and longitudes 76º01´ whereas the S2 is at Shambhu with 30º49´ latitudes and 76º72´ longitudes.

Four representative sampling sites i.e. S1, S2 were identified keeping in view of the variation in the microhabitat and hydrological features of the river Ghaggar. Sampling sites were recognized with an objective of obtaining Phytoplankton samples. Samples were collected on monthly basis from 2017 to September 2019 for a period of two years. Plankton net was made by using nylon bolting cloth having mesh size of (24 mesh/mm2) used for the collection of plankton samples. 100 litres of water was sieved every time through the net. Samples were collected and preserved in 5% formaldehyde solution in plastic sample bottles and transported to the laboratory, for identification and further analysis as per ^{12, 13}. In the laboratory, plankton slides were prepared for identification. Identification and counting of phytoplankton were done by use of binocular light microscope. Sedgwick Rafter Counting Chamber was used to determine their density ¹⁴. The plankton was identified to genus level as per the guidelines given by ^{13, 15, 16, 17}.

Statistical analysis of the data generated was made in Microsoft Excel and PAST software. The statistical calculations like range, statistical mean, standard deviation (S.D between different and phytoplankton diversity were determined.

The percentage occurrence and relative numerical abundance of phytoplankton was subjected to diversity analysis using different indices like Shannon Diversity Index “H” ¹⁸, Pielou Evenness

3. Results and Discussion

In any aquatic environments, the diversity, distribution, and variation in the biotic parameters provide a good indication of energy ²¹. Phytoplankton is characterized as a major source of organic carbon and is situated at the bottom level within these environments ²². The sensitivity and fluctuation in species composition are usually a suitable account to reveal the alteration within an ecosystem ²³. Species diversity responds to changes in environmental gradients and may characterize many interactions that can establish the complicated pattern of community structure. Normally, it is found that any slight alteration in environmental status can change diversity until there is no adaptation or gene flow from non adaptive sources. Index“J” ¹⁹ and Simpson Diversity Index”D” ²⁰. Phytoplankton population was composed of 4 major groups of algae namely Cyanophyceae (blue green algae), Chlorophyceae (green algae), Bacillariophyceae (diatoms) and Euglenophyceae in water ecosystem. At both the sites (S1, S2) a total of 35 genera of phytoplankton were recorded belonging to 4 major classes. Among these Bacillariophyceae with 20 genera were found to be dominant followed by Chlorophyceae with 7 genera, Cyanophyceae with 4 genera and Euglenophyceae with 3 genera during the study period. Phytoplankton abundance at S1 and S2 of the river Ghagger Bacillariophyceae> Chlorophyceae> Cyanophyceae> Euglenophyceae.

The study also shows that, the species like Nitzschia palea, Synedra ulna, Euglena acus, Fragilaria sp., Oscillatoria sp., Gomphonema sp. Meridion sp., was present throughout the study period and they are the indicator of bad water quality. Following genera were observed as pollution indicators. They are Fragillaria, Nitzchia, Navicula, Cymbella, Synedra, Oscillatoria, Closterium, and Chlorococcum. Euglena gracilis shows Organic pollution in river Chlorella vulgaris, water industry and sewage waste pollution indicator. Other researchers also observed similar seasonal observation viz. minimum density of phytoplankton during monsoon and maximum during summer in Chatla Lake Assam ²⁴. Bioindication showed a low diverse community in the monsoon period with better water quality than in preand post-monsoon ²⁵.

At the (S1, S2) maximum species diversity and species evenness was recorded during pre monsoon Season and minimum species diversity during monsoon season. At S1, Shannon-Weaver index for phytoplankton population ranges from 3.472 to3.521, Simpson’s index of phytoplankton diversity ranged from 0.9675 to 0.9703 and species evenness ranges from 0.9471 to 0.9703 in different seasons of this particular water body. At S2 site, Shannon-Weaver diversity index ranges from 3.422 to 3.513, Simpson’s diversity index ranges from0.964 to0.969 and species evenness of phytoplankton diversity ranges from0.9006 to0.9867 of this selected water bodyshown in Table 1 and Table 2. The result of present investigations of diversity indices indicates that the wetland is moderately polluted. Among the sites (S1, S2) maximum species diversity indices was calculated at S2 site and minimum species diversity was recorded at S1. Calculations give indications that river water is polluted.

4. Conclusion

Low diversity in polluted water might be due to the fact that many pollution sensitive species were eradicate from the community and only a few pollution tolerant organisms thrive in the absence of competition and in the presence of abundant food supply. So, phytoplankton study is very important because they act as primary producers and an efficient bio-indicator for water quality. Phytoplankton diversity their percentage gives us forewarning about the quality of pollutants in water body. Sheer presence of these bioindicators is indicative of the status of water bodies and can be used as a reliable tool for the assessment of polluted quality of river water. Ghaggar is observed as polluted river as it receive pollutants from many sources. Thus, overall present study revealed that the extent of pollution in the river which is directly affecting the flora and fauna. Hence, this study suggests that regular bio-monitoring of this water body should be carried out to keep its flora and fauna intact for the years to come.

References