Environmental Science A Study of interrelationships Unite 6 Soil and its uses
Unite 6 Unite 6 Soil and its Uses Soil and its Uses Environmental Science Environmental Science A Study of interrelationships A Study of interrelationships
Useful Words and Expressions Crust-地壳 Mantle-地幔 Lithosphere-岩石圈 Asthenosphere-岩流圈 Plate Tectonics-板块构造学说 Weathering-风化 Hydrolysis-水解 ava-熔岩 Parent materia-原生材料
Useful Words and Expressions • Crust –地壳 • Mantle –地幔 • Lithosphere – 岩石圈 • Asthenosphere – 岩流圈 • Plate Tectonics – 板块构造学说 • Weathering – 风化 • Hydrolysis – 水解 • Lava –熔岩 • Parent material –原生材料
Useful Words and Expressions Humus一腐殖质 Soil profile-土壤剖面 Soil texture-土壤构成 Soil structure-土壤结构 Soil erosion-土壤侵蚀 Contour farming-仿地形耕种 Strip farming-间耕 Soil conservation practices-水土保持
Useful Words and Expressions • Humus – 腐殖质 • Soil profile – 土壤剖面 • Soil texture – 土壤构成 • Soil structure – 土壤结构 • Soil erosion – 土壤侵蚀 • Contour farming – 仿地形耕种 • Strip farming – 间耕 • Soil conservation practices –水土保持
Geologic Processes(地质学过程) Crust(地壳)- Extremely thin, less-dense soil Mantle(地幔)- Makes up majority of earth Oceanic crust Uppermost mantle Inner portion is sAid km是 Asthenosphere (part of mantle) 200km core mantle continues downward Lithosphere:岩石圈 ter portion Capable of flow Asthenosphere:岩流圈 (the plastic louter layer
Geologic Processes (地质学过程 ) • Crust (地壳） - Extremely thin, less-dense soil. • Mantle（地幔） - Makes up majority of earth. Lithosphere: 岩石圈 Asthenosphere: 岩流圈 Surrounds core of iron；Inner portion is solid Outer portion capable of flow (the plastic outer layer )
Geologic Processes Plate Tectonics(板块构造学说)- is the concept that the outer surface of the Earth consist of large plates composed of the crust and the outer portion of the mantle ( lithosphere and that these plates are slowly moving over the surface of the liquid outer mantle Heat from earth core causes movement , Plates are pulling apart in some areas, and colliding in others due to the fact that the movements of the plates on this plastic outer layer of the mantle are independent of each other Building processes counteracted by processes tending to tear down land
– Heat from earth core causes movement. Plates are pulling apart in some areas, and colliding in others due to the fact that the movements of the plates on this plastic outer layer of the mantle are independent of each other. Geologic Processes • Plate Tectonics（板块构造学说） - is the concept that the outer surface of the Earth consist of large plates composed of the crust and the outer portion of the mantle （lithosphere ） and that these plates are slowly moving over the surface of the liquid outer mantle. – Building processes counteracted by processes tending to tear down land
Eurasian Plate North American Juan de Fuca Plate San Andreas Caribbean Arabian Plate ilippine Plate Pacific Plate Indian-Australian Plate Nazca Plate African Plate American Plate Antarctic Plate Antarctic Plate Direction of plate motion Subduction zone (sawteeth point toward Spreading ridge overriding plate) Transform fault
Weathering Weathering -Factors bringing about fragmentation or chemical change of parent material (reducing the size of the particle) Mechanical weathering Chemical weathering
Weathering • Weathering - Factors bringing about fragmentation or chemical change of parent material (reducing the size of the particle). – Mechanical weathering – Chemical weathering
Mechanical weathering-Results from physical forces reducing size of rock particles without changing the chemical nature of the rock Freezing& Thawing temperature changes abrasion of rock particles( caused by force that move and rub rock particles against each other O wind and moving water also move small particles and deposit them at now location, exposing new surface to the weathering process
- temperature changes - abrasion of rock particles ( caused by force that move and rub rock particles against each other) - wind and moving water also move small particles and deposit them at now location,exposing new surface to the weathering process Mechanical weathering- Results from physical forces reducing size of rock particles without changing the chemical nature of the rock
Chemical weathering-chemical weathering involves the chemical alternation of the rock in such a manner that it is more likely to fragment or to be dissolved some small rock fragment may combine with oxygen from the air(when it was exposed to the atmosphere) and chemically change to different compounds some small rock may combine with water molecules (hydrolysis) the oxidized or hydrolyzed molecules are more readily soluble in water and, therefore, may be removed by rain or moving water. 氧化态或水解态岩石分子更易于在水中溶解,因此,它们可随 降雨或水流而迁移
- some small rock fragment may combine with oxygen from the air (when it was exposed to the atmosphere) and chemically change to different compounds. - some small rock may combine with water molecules (hydrolysis) Chemical weathering- chemical weathering involves the chemical alternation of the rock in such a manner that it is more likely to fragment or to be dissolved - the oxidized or hydrolyzed molecules are more readily soluble in water and, therefore, may be removed by rain or moving water. 氧化态或水解态岩石分子更易于在水中溶解，因此，它们可随 降雨或水流而迁移
Soil and land Land- Portion of world not covered by water Soil -a thin covering over the land consisting mixture of minerals, organic material, living organisms, air, and water Soil formation-a combination of physical, chemical and biological process over time the soil building begins with the fragmentation of the parent material Parent material -ancient layers of rock, or more recent geologic deposits from lava(4) flows or glacial activity
Soil and Land • Land - Portion of world not covered by water. • Soil – a thin covering over the land consisting mixture of minerals, organic material, living organisms, air, and water. • Soil formation – a combination of physical, chemical and biological process over time – the soil building begins with the fragmentation of the parent material – Parent material - ancient layers of rock, or more recent geologic deposits from lava (熔岩） flows or glacial activity