PDF-A review of the effect of terracing on erosion

Luuk Dorren and Freddy Rey Cemagref Grenoble France tel 33476762806 luukdorrencemagreffr freddyreycemagreffr Abstract Terracing is one of the oldest means of saving soil and water. Soil erosion and sediment control is not a new technology The USDA Soil Conservation Service and a number of State and local agencies have been developing and promoting the use of erosion and sediment control devices for years This chapter provides * Earth’s main agent of natural erosion. What is erosion?. Erosion is. -. Agents of Erosion. Agents of erosion include. . --. Running water . is the. . big. . Kahuna. . of. . all. . erosional. Features of River Erosion. 1. Potholes. 2. River Valleys. 3. Gorges and Canyons. 4. Mesa and Butte. 5. Waterfalls. 1. Potholes. Potholes are formed due to stream or river erosion which initiates by simple . Chapter 4.1. Pages 118-127. Key Questions. How does moving water cause erosion?. What land features are formed by water erosion and deposition?. Moving water is the major agent of the erosion that has shaped Earth’s land surface.. Physical Weathering. Weathering. is the breakdown of rock or soil. . Physical . weathering occurs when natural forces, such as wind, running water, and moving ice, physically break up rock and soil into smaller particles. . Chapter 7. Section 7.1 Weathering. Weathering is the process by which rocks on or near Earth’s surface break down and change. . Erosion is the removal and transport of weathered material from one location to another.. The . surface. features of the Earth change as a result of observable physical and chemical processes . Weathering and Erosion. This is a monument . called Cleopatra’s . Needle. It was carved in Egypt around 1450B.C. The sides are carved with hieroglyphs, the writing of ancient Egypt. It stood in the dry, hot Egyptian desert for over 3000 years. During that time, the hieroglyphs remained distinct.. Antony . Lenehan. Remote Sewerage Treatment and Effluent Disposal. Site and soil. Effluent quality and quantity. Application systems- above ground or below ground. Crop/vegetation . s. election and management. Famous formations in Australia. Uluru. 12 Apostles. Wave Rock. The Olga’s. The Three Sisters. Warrumbungle’s. Make your own question which you would like to investigate using the same set up.. For example:. Water Erosion. How Does Moving Water Cause Erosion?. Erosion by water begins with a splash of rain.. Some rainfall sinks into the ground.. Some evaporates or is taken up by plants.. The rest of the water runs off over the land surface.. Nancy . Rogel. Eddie . Guadarrama. . Outline. What is Soil Erosion. Types of Erosion. Factors Affecting Erosion Rates. Human Activities that increase Erosion Rates. How to Prevent Erosion. What is Soil Erosion. formation of landforms. weathering and erosion. The process of weathering and erosion are the main forces behind landscape types. . However, they are not the only reason for a plain, plateau, or a mountain region to form. . PROCESSES. Generate runoff. Saturation excess. Infiltration excess. INFLUENCES. Hydraulic soil properties. Conductivity. Compaction/use history. Ground cover (interception). Antecedent conditions. Existing moisture. Weathering. Weathering is the process that breaks down rock and other substances at the Earth’s surface. . Heat, cold, water, and ice all contribute to weathering.. Repeated freezing and thawing for example can crack rock apart into smaller pieces. .