Recap, Glossary

Recap

* Water is one of the most important elements on earth. All plants and animals need water for survival.

* About 71% of the earth's surface is covered by water. Out of this, only about 2.8% is fresh water and the remaining 97.2% is saltwater found in seas and oceans.

* Hydrological cycle is a global sun-driven process where water is transported from oceans to atmosphere, from atmosphere to land and from land back to oceans.

* There are six main components in hydrologic cycle. They are evapotranspiration, condensation, precipitation, infiltration, percolation, and runoff.

* The precipitation in the warmer parts of the world is in the form of rain or drizzle. The common types of precipitation include rain, sleet, freezing rain, hail, and snow.

* Infiltration occurs near the surface of the soil and delivers water from the surface into the soil and plant rooting zone. Percolation moves it through the soil profile and rock layers to form groundwater.

GLOSSARY

1. Aquifer: It is an underground layer of water - bearing permeable rocks, rock fractures or unconsolidated materials (gravel, sand or silt) நீர்கொள்பறை

2. Evapotranspiration: It refers to the water lost through evaporation from the water bodies and transpiration from vegetation ஆவியீரப்பு

3. Infiltration: the seepage of water into soil or rock நீர ஊடுருவல்

4. Percolation: the slow movement of water through the pores in soil நீர உட்சிதல்

5. Precipitation: falling products of condensation in the atmosphere, as rain, snow, or hail பொழிவு

6. Runoff: overflow நீர வழிந்தோடல்

REFERENCES BOOK

1. Davie, T. (2008). Fundamentals of Hydrology (Second Edition – Routledge Fundamentals of Physical Geography Series). Routledge - Taylor & Francis Group, New York.

2. Musy, A. and Higy, C. (2011). Hydrology: A Science of Nature Science Publishers, Enfield. 3. Raghunath, H.M. (2006). Hydrology – Principles, Analysis and Design (Revised Second Edition). New Age International (P) Limited, Publishers, New Delhi.

4. Rakhecha, P.R. and Singh, V.P. (2009). Applied Hydrometeorology, Springer Publishing Company, Dordrecht and Capital Publishing Company, New Delhi.

5. Viessman, W. (Jr), Lewis, G.L. (2003). Introduction to Hydrology (Fifth Edition). Prentice-Hall of India Private Limited, New Delhi.

INTERNETRESOURCES

*http:// www.fao.org/docrep/X0490E/x0490e04.htm.

* https: / www.sciencelearn.org.nz (UniversityofWaikato).

* https://cals.arizona.edu/azmet/etowhat1.pdf.

*https://pmm.nasa.gov/education/sites/default/files/lesson_plan_files/evaporation_investigation_lesson_plan.pdf.

*https://www.watereducation.org/aquapedia-background/runoff.