1. ater that collects on the surface of the ground.
2. Chemical weathering
2.1. the erosion or disintegration of rocks, building materials, etc., caused by chemical reactions (chiefly with water and substances dissolved in it) rather than by mechanical processes.
3. Erosion
3.1. the process of eroding or being eroded by wind, water, or other natural agents.
4. Soil
4.1. the upper layer of earth in which plants grow, a black or dark brown material typically consisting of a mixture of organic remains, clay, and rock particles.
5. Sand
5.1. a loose granular substance, typically pale yellowish brown, resulting from the erosion of siliceous and other rocks and forming a major constituent of beaches, riverbeds, the seabed, and deserts.
6. Silt
6.1. fine sand, clay, or other material carried by running water and deposited as a sediment, especially in a channel or harbor.
7. Groundwater
7.1. water held underground in the soil or in pores and crevices in rock.
8. Zone of saturation
8.1. The phreatic zone, or zone of saturation, is the area in an aquifer, below the water table, in which relatively all pores and fractures are saturated with water.
9. Surface water
10. River basins
10.1. A river basin is the portion of land drained by a river and its tributaries.
11. Watersheds
11.1. A watershed is the area of land where all of the water that falls in it and drains off of it goes to a common outlet.
12. Landslides
12.1. the sliding down of a mass of earth or rock from a mountain or cliff.
13. Tsunamis
13.1. a long high sea wave caused by an earthquake, submarine landslide, or other disturbance.
14. Pollution
14.1. the presence in or introduction into the environment of a substance or thing that has harmful or poisonous effects.
15. Weathering
15.1. wear away or change the appearance or texture of (something) by long exposure to the air.
16. Physical Weathering
16.1. The definition of physical weathering is rocks, soil and minerals being slowly broken down or broken apart by the Earth's environment such as pressure, temperature, water and ice.
17. Frost wedging
17.1. Freeze wedging is caused by the repeated freeze-thaw.
18. Acid precipitaion
18.1. precipitation (as rain or snow) having increased acidity caused by environmental factors (as atmospheric pollutants)
19. ph Scale
19.1. A measure of acidity or alkalinity of water soluble substances (pH stands for 'potential of Hydrogen').
20. Clay
20.1. noun. a natural earthy material that is plastic when wet, consisting essentially of hydrated silicates of aluminum: used for making bricks, pottery, etc. earth; mud. earth, especially regarded as the material from which the human body was formed.
21. Water Table
21.1. the level below which the ground is saturated with water.
22. Zone of aeration
22.1. Groundwater is all the water that has penetrated the earth's surface and is found in one of two soil layers.
23. Infilration
23.1. Infiltration (hydrology) Infiltration is the process by which water on the ground surface enters the soil.
24. Aquifers
24.1. a body of permeable rock that can contain or transmit groundwater.
25. Flooding
25.1. cover or submerge (a place or area) with water.
26. Geohazards
26.1. Geohazards are geological and environmental conditions and involve long-term or short-term geological processes.
27. Sinkholes
27.1. a cavity in the ground, especially in limestone bedrock, caused by water erosion and providing a route for surface water to disappear underground.
28. Barrier Islands
28.1. a fence or other obstacle that prevents movement or access.
29. sail
29.1. a piece of material extended on a mast to catch the wind and propel a boat, ship, or other vessel.
