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4. MATERIALS AND METHODS

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4.1 WATER QUALITY STUDIES

Water Sample Collection: The monthly grab samples were collected in polyethylene container at the points were stream flow measurement was taken. The water sample for analysis was collected at each sampling station and subsequently stream flow was measured. The samples for phytoplankton analysis were collected in the same site by filtering 25 liter of water in bolting silk net No.25. In the case of tributaries the flow measurement and water quality samples were taken immediately the tributary confluence in to reservoir at monthly basis. The water samples were stored in 4° C. Following methods were employed for the estimation of various factors:

Biological analysis: Changes in water quality exert a selective action on the flora and fauna, which constitute the living population of water, and the effects produced in them can be used to establish biological indices of water quality (Palmer, 1980). Biological approaches to monitoring river water quality were introduced early in the 20 th century (Kolkwitz and Marsson, 1908), although they began to be widely adopted 40 years ago. In practice, the most important use of biological monitoring is to deal with situations where there is a range of contaminants whose biological effects may be synergistic or antagonistic, or where biological data give results that apparently contradict those yielded by chemical analysis (Whitton, 1991). Water quality affects the abundance, species composition, stability, productivity, and physiological condition of indigenous populations of aquatic organisms. Therefore, the nature and health of the aquatic communities is an expression of the quality of the water, Biological methods used for assessing the water quality includes the collection, counting, and identification of the aquatic organisms (APHA, 1985).

Coliform test: This method is intended to indicate the degree of contamination of water with wastes. The water may serve as a vehicle for the transmission of waterborne diseases. Polluted water contains vast amounts of organic matter that serve as an excellent nutrient sources for the growth and multiplication of the microorganisms. The presence of non-pathogenic organisms is not of major concern, but intestinal contaminants of fecal origin are important. Analysis of water samples on a routine basis would not be possible if each pathogen required to detection. Therefore water is examined to detect Escherichia coli, the bacterium that indicates the fecal pollution. Since Escherichia coli is always present in faeces and whose normal habitat is the intestine of humans and other higher animals. Escherichia coli, the Gram negative, non-spore forming bacilli that ferment lactose with the produce H₂S gas. The medium contains Ferrous ammonium citrate, which reacts with the H₂S and turns in to black colour with in 48 hours.

Medium composition:

Peptone, Dipotassium hydrogen phosphate, Ferric ammonium citrate, sodium thiosulphate, 1ml Teepol and 50 ml distilled water.

Procedure:

1ml concentrated medium is absorbed on folded tissue paper; the tissue paper is kept in dry sterilised bottles; 20 ml of water sample to be tested is poured into this bottle; it is incubated at 30 - 37 ° C for 48 hours; if the water is contaminated by sewage the contents of the bottle turns black within 48 hours.

Phytoplankton:

The term ‘plankton' refers to those microscopic aquatic forms having little or no resistance to currents and living free floating and suspended in open pelagic waters. The phytoplankton (microscopic algae) occurs as unicellular, colonial, or filamentous algae. Phytoplankton long has been used as indicator of water quality. Some species flourish in highly eutrophic waters while others are very sensitive to organic and/or chemical wastes. Some species have been associated with noxious blooms, sometimes creating offensive tastes and odours or toxic conditions. Because of short life spans, phytoplankton responds quickly to environmental changes, and hence standing crop and species composition indicate the quality of the water mass in which they are found. They strongly influence certain non-biological aspects of water quality such as pH, colour, taste, and odour.

Sample collection and preservation: The sample were collected by cone shaped phytoplankton net made up of bolting silk net No 25 (200 meshes per inch; inside measurement of mesh is 0.054mm). The wider end of the net is kept open by a metal hoop. A plastic 100 ml-receiving vessel closed the narrow end of the net. A known volume of the sample (25 litre) is filtered for phytoplankton. Sedimentation of phytoplankton was made by 4% formaldehyde. For identification of phytoplankton algal monographs by Prescott (1962) and Indian freshwater microalgae by Anand (1998) were followed. The counting of the phytoplankton was done by drop count method (Trivedy and Goel, 1984). The results are expressed as organisms per ml of sample.

Palmer (1969) proposed a pollution index based on phytoplankton algae and their tolerence to organic pollution. From information on pollution tolerant algae compiled from many authors, the genera and species considered significantly were found to fall in stable series. More than 60 genera and 80 species have been recorded to tolerate varying levels of organic pollution. The pollution status of water is determined based on their indices as shown in Table 2.

4.2 HYDROLOGICAL INVESTIGATION

Hydrology is the science that deals with the origin, distribution and properties of water on the earth including that in the atmosphere in the form of water vapour, on the surface as water, snow or ice, and beneath the surface as ground water. The study of hydrology deals with the three important phases of the hydrological cycles, namely rainfall, runoff and evaporation. A considerable portion of the water returned as stream flow, the movement of water under force of gravity through well-defined, semi permanent surface channels. The measurement, analysis, and interpretation of stream flow data are therefore important phases of hydrology (Linsley et al., 1949).

Velocity:

The velocity is the rate of flow of the water. The velocity of the stream water is calculated by floats method. The time taken for the float to reach the measured distance (usually one meter) is calculated by stopwatch. Velocity is expressed in meters per second (m/s)

Velocity =		Distance in meters
		Time in seconds

Discharge:

Discharge is the volume of water passing through any point in the watercourse over a specified period of time. The product of velocity and cross sectional area of a stream is known as discharge. Discharge is expressed in cubic meters/second (m³/s)

Discharge = A* V

Where, A = Average cross sectional area of the stream (m²)

Cross sectional area = width * depth

V = Flow velocity

Catchment area:

Using the contour lines on a topographical map (1:50000) the catchment boundaries are delineated. The ridge tops where followed to draw the boundaries of the catchment area around the streams that appears as downhill points in the toposheets. The boundary should be perpendicular to the contour lines it intersects. The tops of mountains are often marked as dots on a map and the location of roads, which follow ridges are other clues (Ramachandra.T.V, 1999).

4.3 CATCHMENT INVESTIGATION

4.3.1 GIS AND REMOTE SENSING

To understand the landuse pattern of the study area initially a base map was prepared using Survey of India toposheet (1: 50000 scale). The base map was then superimposed on the geocoded satellite data and visual interpretation of the false colour composite (FCC) was carried out in consultation with the Survey of India toposheet and ground truth in Idrisi 32 and map was digitized using Geographic Information System (software Mapinfo version 6.0).

4.3.2 VEGETATION ANALYSIS

The ideal method to sample the catchment vegetation is a combination of transect with quadrat. In this method the square plot of definite area (20 X 20 meter = 400 meter 2 = 0.04 hectare) are laid in a straight line transect with inter-quadrat distance of 20 meters. All the plants that are 30 cm or more in GBH [Girth at breast height or height at 130 cm] are considered as tree and identified, or collected if field identification was not possible and the samples were pressed for herbaria for future identification. The GBH was measured for each tree at the height of 130 cm above the ground and approximate height in meters (Chandran 1999). The cross sectional area of a tree estimated at breast height is called the basal area; it is normally expressed in m² . The sum of the basal areas of all trees on an area of one hectare is symbolized by Gm² ha^-1 (Philip, 1994).

Figure 5: Transect cum quadrat method of Vegetation analysis.

The locality data for the vegetation sampling was obtained from the 1: 50000 toposheets published by Survey of India and a portable global positioning system gives the latitude, longitude and altitude of the locality.

Datasheet for Vegetation sampling:

Taluk:

Village:

Hamlet:

Stream name:

Sub-basin:

Latitude and longitude:

Forest type:

4.3.3 SOIL ANALYSIS

The soil quality concept evolved throughout the 1990s in response to increased global emphasis on sustainable land use and with a holistic focus emphasizing that sustainable soil management. Soil samples were collected, which were representative of the entire catchment area. Samples were collected 5 centimeters below the ground using an auger and core.

Soil quality assessments provide a better understanding and awareness that soil resources are truly living bodies with biological, chemical, and physical properties and processes performing essential ecosystem services. The following methods were employed for the estimation of various factors: