Current World Environment

Introduction

Water is the most essential thing in living system. In last few years the water pollution problem has reached a crisis point. The term pollution is defined as the deterioration in chemical, physical and biological properties of water by human and industrial activity. The Industrial wastes, sewage and agricultural run off can overload ground water with chemical wastes and nutrients and make water supply toxic.¹

Jhunjhunu district is situated in north-East Part of Rajasthan State. In South East part of district there falls a industrial area, various industries like marble, Iron, dyes etc are present, These industries pour their effluents unplanndely and the effluent through various big and small drains reaches to Khemi Sati Pond, where it got mixed with the sewage water coming from city side, Industrial effluents and sewage water through various drains reaches Khemi Sati area and finally ends up in the form of a pond. Around this pond, people are engaged in farming and they use this wastes water for irrigating fields.

No other means like tube well, hand pump present for irrigation purposes. The plants/crops growing here show early maturity, Necrosis, chlorosis, stunted growth, leaf die back etc which might be due the used of this waste water. There is a strong possibility of accumulation of heavy metals in plants/crops a large number of populations is dependent on them for their dietary purposes, so it will affect human population and make them diseased. With all this view, the recent study is done with the following objectives:-

1. Analysis of Physico-chemical parameters of industrial effluents sewage water and irrigation water.
2. Analysis of Heavy metals [Fe, Cu, Zn, Mn] in irrigation water.

Experimental

For the analysis of Physico-chemical parameters in water twenty five samples were collected in wide mouth plastic bottle, out of these 25 samples W₁-W₅ are of marble industry, W₆-W₁₀ are of Dye Industry, W₁₁-W₁₅ are of Iron industry, W₁₆-W₂₀ are of Sewage water and W₂₁-W₂₅ are Irrigation water. In W₂₁-W₂₅ samples heavy metals [Fe, Cu, Mn, and Zn] were also done. For the analysis of Physico-Chemical parameters and Heavy metals Standard procedure was followed.²

Results and Discussion

pH

The prescribed pH range for irrigation water is 5.4 to 7.0. The analysis shows that irrigation water of area have pH value above prescribed level, this will result in leaf chlorosis, reduced root growth, stunted shoot growth and poor flower development.³

Ec

From the above table it is clear that effluent of marble, Iron, Sewage water and irrigation water is only suitable for soil of good Permeability; while effluent of Dye industries can only be used in soil of moderate to good Permeability⁴.

T.D.S

The total dissolved solids are mainly the inorganic mineral matter and sometimes some organic large variety of slats such as chlorides, carbonates, bicarbonates, nitrates and sulphates of Ca⁺², Na⁺,K⁺ ,Fe²⁺ etc. Which impact total salts to water. If any one of them becomes in excess, the water is un useful for drinking and for irrigation purpose.

The tolerance limit of TDS for irrigation water is 2100 mg/l. From the above analysis it is clear that industrial effluent, sewage water and irrigation water all have low value of TDS

Total Hardness

The tolerance limit for hardness is 1300 mg/L (26 meq/L) under favourable conditions for plants. The concentration of total hardness is very low in all water of area under investigation.

Sodium (Na⁺)

The required concentration of sodium is 30 meq/L. The above analysis shows that range of sodium is suitable for irrigation purpose.

SAR (Sodium Absorption Ratio)

SAR is used as a new basis for sodicity and is calculated as 

Na⁺ / Ca⁺² + Mg⁺² / 2

According to BIS, Safest limits of SAR have been recognized as 10 but this is relaxable up to 30 in most favourable conditions of plants. The value of SAR was found low in all effluents of marble, dye, Iron industries and Irrigation water, while in sewage water all the samples have high value of SAR.⁵

Potassium (K⁺)

Potassium is an essential element for plant growth. Potassium tolerance limit for irrigation water is 0.23 Meq/L to 0.75 Meq/L under favourable conditions.

From the above analysis it is clear that level of potassium in industrial effluents is not suitable for irrigation purpose as potassium is deficient, while in irrigation water, sewage water Potassium is present in Permissible limit. In deficient condition Potassium will cause yellow colour of leaves and affects, Photosynthesis process, while in toxic level it induce iron chlorosis and magnesium deficiency.⁶

Chloride (Cl^–)

According to BIS, tolerance limit of Cl^– for irrigation water is 600 mg/L (17 Meq/L). Wheat, Sorghum, Cotton, barely is able to tolerate chloride in concentration from 62 to 80 Meq/L.

From the above analysis it is clear that level of chloride is very less in industrial effluents, except one sample W₁₂ of iron industry, irrigation water, and sewage water, is not suitable for plants growth.

Chloride ion was found to affect Plant potentials through osmotic adjustments, such as turgor pressure, leaf water potential and osmotic potential. Influence of chloride on crop growth is hasting of maturity of small grains, Chlorosis in the younger leaves and over all wilting of the plant are the two most common symptoms of chloride deficiency.⁷

Nitrates (NO₃^–)

According to W.H.O. Permissible Concentration of nitrates is 45 Mg/L for irrigation water from the above analysis it is clear that concentration of nitrate is low in all water and is not safe for irrigation.

Sulphate (SO₄^–2)

The BIS Prescribed 400 mg/L (12 meq/L) as Permissible limit of sulphate ion in irrigation water in absence of alternative source. Presence of Sulphate beyond limit is harmful as it directly affects the concentration of Ca⁺² & Mg⁺²

The concentrations of sulphate ions observed in the present study are less in range prescribed by BIS, thereby indicating that this water is not safe for irrigation.⁶

Sulphate which has pronounced retarding effect on plant growth is characterized by uniformly chlorotic plant and stunted growth this seems in many plants there symptoms resemble those of nitrogen deficiencies. Sulphate does not appear to be easily translocated from older to younger plants.

Table 1: Quality Parameters of Irrigation water of Jhunjhunu District (Rajasthan)