1. Prepared by T. Madhavan, Lecturer in Zoology, Directorate of School Education., Pondicherry. An Illustration for the students who aspire for medical studies.

2. Prepared by T. Madhavan, Lecturer in Zoology, Directorate of School Education., Pondicherry. An Illustration for the students who aspire for medical studies. Clean, Fresh water is essential for nearly every human activity including domestic, vocational, agricultural, medicinal and cultural needs. Freshwater resources : - Glaciers, Ice, snow - - Lakes and Ponds - - Ground water - - Wet lands -

3. Prepared by T. Madhavan, Lecturer in Zoology, Directorate of School Education., Pondicherry. An Illustration for the students who aspire for medical studies. Ground water: - Next largest reservoir of freshwater. - Water held in the lower soil is known as water table. - Porous –water bearing layers of sand, gravel and rock are called aquifers. Glaciers, Ice, snow: - of the 3% of all water that is fresh, - about ¾ is tied up in glaciers, ice caps and snow fields. - occur only at high altitudes or high latitudes. Freshwater resources

4. Prepared by T. Madhavan, Lecturer in Zoology, Directorate of School Education., Pondicherry. An Illustration for the students who aspire for medical studies. Lakes and Ponds: - Lakes are inland depressions that hold freshwater year around, - Ponds are small temporary or permanent bodies of shallow water. - Lakes and ponds are still a minor share of total world water supply. Freshwater resources Wet lands: - Bogs, swamps, wet meadows marshes play a vital & often a minor role

5. Prepared by T. Madhavan, Lecturer in Zoology, Directorate of School Education., Pondicherry. An Illustration for the students who aspire for medical studies. Fresh water shortages Reasons for freshwater shortage 1) Evaporations, Leakage and siltation 2) Loss of free flowing rivers 3) Depleting ground water 4) Salt Water Intrusion 5) Natural forces 6) Human causes

6. Prepared by T. Madhavan, Lecturer in Zoology, Directorate of School Education., Pondicherry. An Illustration for the students who aspire for medical studies. Fresh water shortages: Reasons Natural forces:  by poor rain fall, hot winds, rivers changing courses. Depleting ground water  o ver use of the supplies, drying of natural springs,  disappearence of the wetlands, rivers and lakes  heavy pumping out of water, drying aquifers

7. Prepared by T. Madhavan, Lecturer in Zoology, Directorate of School Education., Pondicherry. An Illustration for the students who aspire for medical studies. Human causes  increased population,  rapid urbanization,  poor sewage systems,  improper cultivation methods Salt Water Intrusion:  Over use of ground water  Industrialization Fresh water shortages Reasons

8. Prepared by T. Madhavan, Lecturer in Zoology, Directorate of School Education., Pondicherry. An Illustration for the students who aspire for medical studies. Fresh water shortages: Reasons Loss of free flowing rivers:  drowned by reservoir impoundments,  turning to linear, sterile irrigation channels Evaporations, Leakage and siltation:  It happens in freshwater lakes and ponds.

9. Prepared by T. Madhavan, Lecturer in Zoology, Directorate of School Education., Pondicherry. An Illustration for the students who aspire for medical studies. To increase local supplies, and stabilize the water reserve the following measures can be helpful in managing the water resources. a.Seeding clouds b.Desalination c.Dams, reservoirs, canals and Aqueducts d.Watershed management e.Rain water harvesting f.Better agricultural practices g.Domestic conservation h.Industrial conservation i.Saving water – an individual’s role

10. Prepared by T. Madhavan, Lecturer in Zoology, Directorate of School Education., Pondicherry. An Illustration for the students who aspire for medical studies. Seeding clouds with dry ice or pottassium iodide particles sometimes can initiate rain if water laden clouds and conditions that favour precipitation are present. Desalination Desalination of sea water is costlier, but through the technology of distillation, reverse osmosis a welcome water supply provided in Middle east countries like Dubai, Oman etc., where there is no other access to freshwater. Fresh water Management

11. Prepared by T. Madhavan, Lecturer in Zoology, Directorate of School Education., Pondicherry. An Illustration for the students who aspire for medical studies. Dams, reservoirs, canals and Aqueducts Dams, reservoirs, canals and Aqueducts trap and tranfer water from areas of excess to areas of deficit using canals, tunnels and underground pipes. Watershed management : A series of small dams or tributary streams can hold back water before it becomes a great flood. Ponds formed by these dams provide useful wildlife habitat and stock watering facilities. Eliminates the need for massive construction projects and huge dams. Fresh water Management

12. Prepared by T. Madhavan, Lecturer in Zoology, Directorate of School Education., Pondicherry. An Illustration for the students who aspire for medical studies. Rain water harvesting It is the activity of collecting rainwater directly or recharging it into ground to improve ground water storage in the aquifer. By this water table depletion can be reduced nad intrusion of sea water in coastal areas can be arrested. Fresh water Management

13. Prepared by T. Madhavan, Lecturer in Zoology, Directorate of School Education., Pondicherry. An Illustration for the students who aspire for medical studies.

14. Prepared by T. Madhavan, Lecturer in Zoology, Directorate of School Education., Pondicherry. An Illustration for the students who aspire for medical studies. Industrial conservation : In industries dry cooling systems must be installed, Cooling water can be recharged, some industiral wate water may be treated, recyled and reused.

15. Prepared by T. Madhavan, Lecturer in Zoology, Directorate of School Education., Pondicherry. An Illustration for the students who aspire for medical studies. Better agricultural practices : Sound farming and foresting practices can reduce runoff. Retaining crops residues on fields reduces flooding. Minimizing ploughing and forest cutting on steep slopes protect watersheds. Wetlands conservation preserves natural water storage capacity and aquifer recharge zones. Domestic conservation : The use of washing machines, dishwashers, and low volume shower heads can reduce water loss. Fresh water Management

16. Prepared by T. Madhavan, Lecturer in Zoology, Directorate of School Education., Pondicherry. An Illustration for the students who aspire for medical studies. Saving water – an individual’s role : AS an individual you can conserve water by the following methods. - Take shorter showers - Don’t wash car, bikes often - Don’t allow tap run while washing dishes, food. - Don’t allow tap run while brushing teeth. - Use native plants in your garden. - Practice the Rock garden instead of lawn - Some Xerophytic landscaping is better. - Use low-flow showers, and low-flow flush toilets. - Use recycled water for lawns, and car washing. - Check taps for leaks.

17. Prepared by T. Madhavan, Lecturer in Zoology, Directorate of School Education., Pondicherry. An Illustration for the students who aspire for medical studies.