Metal pollution in the river Godavari in India, due to discharges of liquid wastes from a paper mill, has been studied for a period of two years. At the discharge point and 1 km from the point of discharge, iron, manganese, and zinc were recorded in high concentrations, whereas cadmium and chromium were observed in low concentrations. No metal was in detectable concentration in water before the river receives the effluents. A considerable drop in pH values and an appreciable increase in organic matter, hardness, and calcium levels were noticed after entry of wastes. Diatoms were more diversified in fresh water, whereas cyanobacteria were more prevalent both qualitatively and quantitatively at the polluted stations. Mathematical equations involving heavy metals and physicochemical factors were drawn for better understanding of the distribution of algae.

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Citrullus lanatus (water melon) is popular fruit and the seeds were rich in oil and protein, this oil could be exploited as edible oil. Citrullus lanatus contains about 6 per cent sugar and 92 per cent water by weight. As with many other fruits, it is a source of vitamin C. The seed being an excellent source of energy and the dried composition of watermelon per 100 g edible portion (50-70% of the mature fruit) include: water 91.5 g, energy 134 KJ (32 kcal), protein 0.6 g, fat 0.4 g, carbohydrates 7.20 g. The favorable functional properties makes the seed and the oil suitable for human consumption and therefore the result of this research work would provide further information on the domestic and industrial usage of the seed and seed-oil.

The impact of liquid wastes from a paper mill on the benthic diatoms in flowing waters has been studied for a period of two years. Water and algal samples were analysed at monthly intervals at three sites along the course of the river, along with raw effluents. The water before the confluence of effluents was well oxygenated with an alkaline pH. Organic matter, NH3 and nutrients were recorded at low concentrations. At the entry of effluents, the water showed considerable decline in dissolved oxygen content, increase in organic matter, hardness, Cl, HCO3 and total dissolved solids. Diatoms constituted 61% by numerical abundance and were reduced to 25% of total algae at the entry of effluents. Multiple regression analysis was employed to discover the relative importance of various physicochemical variables on the abundance and distribution of diatoms at various sampling stations. Mathematical equations were derived involving the physicochemical variables for better prediction of algal number.

Properties of the mine waste represented the toxic nature to human health and may pose numerous risks to the local environment. Although the recorded radioactivity level in these tailings is very low, but to avoid any long term effect of these tailings on the atmosphere as well as native living things, the tailings need to cover with soil. This reduces gamma radiation and radon emission levels. However, to consolidate the radioactivity and remediate the contaminants in the tailings on a sustainable basis, the area needs to be revegetated by candidate plants. Remediation of heavy metal-contaminated sites using plants presents a promising alternative to current methodologies. Therefore, the study was to evaluate the ex-situ phyto-remediation of uranium mine tailing ponds by amending with land soil followed by invading to grow predominant native plant species. Three volumes of the pot culture experiment were carried out i.e. additions of land soil to mine tailing at 0, 50, and 100 percent by volume with four abundance plant species of S. spontaneous (terrestrial), P. vittata (fern) and T. latifolia and C. compressus (aquatic species) were selected in the study. After appropriate preparation U, Mn, Fe, V, Ni, Cu and Zn which were the major contaminants and the pH and EC in soil fractions and also growth parameters in plant materials were analyzed at five stage intervals in the duration of four months. The addition of soil was found significant change in pH to alleviate the toxic effects that heavy metals have on plant health, hence the enhanced growth and survivability was reached. Even while redistributing metals to a less available form, during the remediation the plant species have the capabilities to accumulate substantial amount of toxic metals. The metal concentrations in the plants were found in the order Fe50.92 > Mn7.22 > Zn0.94 > Cu0.92 > Ni0.65 > V0.18 > U0.07 and accumulated in the order Zn0.021 > Cu0.019 > Mn0.014 > Ni0.013 > U0.002 > V0.001 > Fe0.001. The results of the study indicate that C. compressus and S. spontanium were found to be the candidate species for Phyto-remediation (i.e. either accumulation and non-accumulation or consolidation respectively) of contaminants in soil amended Uranium mine tailings. For maximum accumulation, C. compressus harvesting need to be done at after the fourth month of plantation and for consolidation, S. spontanium plantation was greatly recommended. It also confirms that the land soil could be the best amendment for remediation of abandoned mine waste.