ABSTRACT
Pallikaranai wetland has high ecological significance as it has been a home for other associated biodiversities. This wetland is highly polluted due to the rapid industrialization, urbanization and dumping of solid waste. The water quality of the Pallikaranai wetland has been studied with reference to toxic metals. The metals analyzed include lead, chromium, iron, copper, nickel, zinc and cadmium. The heavy metal analysis in surface waters were in the following range ; Cd : BDL – 0.019 mg l-1, Fe : BDL – 1.52 mg l-1, Cu : BDL – 0.02 mg l-1, Ni : BDL- 0.60 mg l-1, Pb : 0.03 – 1.13 mg l-1, Zn : 0.002 – 0.14 mg l-1 and Cr : 0.10 – 1.52 mg l-1 respectively. The dominance of various heavy metals in the surface water of the Pallikaranai wetland followed the sequence: Pb> Cr > Fe > Ni > Zn > Cd > Cu. The quality of water has deterioted due to the various anthropogenic activities. Most of the metal ions were in higher concentration compared to the standards. It has been observed that the quality of the surface water is not safe for aquatic and domestic life, hence necessary management actions should be taken to control the quality of the surface water.
ABSTRACT
Being the second largest manufacturing industry in India, cement industry is one of the major contributors of suspended particulate matter (SPM). Since plants are sensitive to air pollution, introducing suitable plant species as part of the greenbelt around cement industry was the objective of the present study. Suitable plant species were selected based on the Air pollution tolerance index (APTI) calculated by analyzing ascorbic acid (AA), pH, relative water content (RWC) and total chlorophyll (TChl) of the plants occuring in the locality. Plants were selected within a 6 km radius from the industry and were graded as per their tolerance levels by analyzing the biochemical parameters. From the statistical analysis at 0.05 level of significance a difference in the APTI values among the 27 plant species was observed, but they showed homogenous results when analysed zone wise using one-way analyses of variance. Analyses of individual parameters showed variation in the different zones surrounding the cement industry, whereas the APTI value (which is a combination of the parameter viz. AA, RWC, TChl, pH) showed more or less same gradation. Significant variation in individual parameters and APTI was seen with in the species. All the plants surrounding the cement industry are indicative of high pollution exposure comparable to the results obtain for control plants. Based on the APTI value, it was observed that about 37% of the plant species were tolerant. Among them Mangifera indica, Bougainvillea species, Psidum quajava showed high APTI values. 33% of the species were highly susceptible to the adverse effects of SPM, among which Thevetia neriifolia, Saraca indica, Phyllanthus emblica and Cercocarpus ledifolius showed low APTI values.15% each of the species were at the intermediary and moderate tolerance levels.