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Detailed Ecological Assessment Report 2008 – Keenjhar Lake
the water quite productive for aquatic life. The Total Suspended Solids (TSS) is 2-
5 mg/L, the high TSS value shows that high concentration of non living
particulates originate as catchment, derived silts, clay, mud, organic matter are
present in the water. This high value is due to flood, rain and other waste
materials. They are the major disturbance in water affecting composition and
biomass of the plankton/algae. The lake is highly turbid with a value of 1-8.2, high
concentration of a-biogenic turbidity, whether disturbance or not, water column
mixing as such or in combination with in organic turbidity cause changes in the
light field over time. Consequently, vertical mixing and suspended solids
significantly affect phytoplankton photosynthesis and productivity in aquatic
environment. Conductivity value 50-58.8 M. ohmsx 10 shows the current ions for
production showing algal vegetation production in the lake. The salinity of the
lake is 0.1-0.3 ppt and the presence of Orthophosphate is (0.02-0.03 ug/L). Only
those species with a high tolerance level are able to grow at these levels. High
Humidity (55-60%) value shows that Fungus, Bacteria, Cyanobacteria, Aerial
algae could be present as humidity directly affects light and temperature. Light
transparency was (3.3-4.5 meter). At one meter the water is too much turbid
which affect the light limit as a result algae/phytoplankton photosynthesis and
therefore restrict biomass development from inlet of water. Dissolved oxygen
(7.5-8.8 mg/L) was in sufficient quantity for production of aquatic life like fish,
fauna but this high concentration of dissolved oxygen was due to inlet and outlet
of water and abundance of Phytoplankton/algae. Carbon dioxide CO2 (40-80
ppm) was in sufficient quantity for the growth of phytoplankton/algal species as
increase in CO2 causes increased algal species. Blue green algae were found in
colonies like Microcystis, Oscillatoria, Phormidium etc. and green algae making
mats like Cladophora, Spirogyra, and Chara as well as layer of Cosmarium. A
High value of CO2 shows availability of rock carbonaceous. High Nitrate value of
0.7-2.6 ug/L in summer season increased chlorophyll-a distribution and alternate
high value in cold water, low chlorophyll-a, which means that both nitrate and
temperature plays significant role in chlorophyll distribution. Phosphate (0.3-0.9
ug/L) plays significant role to control the algal growth. Total hardness (120-155
ppm) concentrations show that sufficient quantity of blue green algae was
available in this water. Increase in Calcium hardness (76-78 ppm) increases the
production of green algae. Increase in the concentration of Magnesium hardness
(45-78 ppm) results in the production of colonies of Cyanophyceae. Higher wave
(2-12 inch) reading was due to wind. Taste, odor, and color of the water showed
that it was tasteless, odorless and sometime fish and aquatic vegetations. The
color of the lake in the summer season was gray/ greenish and colorless during
the monsoon season. The water is rich in algal species, which is beneficial for
fauna and fish. Some aquatic vegetation were found in and near surrounding lake
water Ceratophyllum, Equisetum fluviatiles L., Lemna minor, L. gibba, Phragmites
maximus (Forsk.) Chiov., Potamogeton pectinatus, Scirpus debilis, Utricularia
inflata var. minor, Prosopis glandulosa Torr., Typha angustifolia var. elongata
Dudley Wiegand, T. latifolia L., Cyperus, Cynodon dactylon (L.) Pers., Alhaji
maurorum Fisch., Capparis deciduas (Forssk.) Edgew., Acacia modesta Wall,
Euphorbia, Amaranthus, Chenopodiums, Meliaazadrachta indica, dates,
calotropis were recorded.
3.6.2 Winter Flora
The following species of phytoplankton were recorded from Keenjhar during the
winter season. Table 19 gives the list of phytoplankton recorded. Figure 20
shows the distribution of species across phyla.
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