EESC3310 Lecture Notes - Lecture 4: Cover Crop, Aridisol, Crop Residue
25 Apr 2017
School
Department
Course
Professor
Document Summary
Explain soil forming processes that makes soil variable. Understand properties of soil (texture, structure, composition, horizons, cec) and their effects on other aspects of the agroecosystem such as water movement and crop growth. To explain why organic matter is at the heart of soil fertility. Valleys often have deeper soils which is why historically we farmed in valleys. But with population pressure it has been moved to hillsides. Moisture/soil temp helps decide what type of soil will form. Overtime weathering occurs on bedrock and soils form/accumulate. Weathering of bed ock that creates smaller pieces of rock that break down over time. Often in compacted soils due to pressure. Plant roots and hairs that excrete sticky organic chemicals that bind soil particles together. Depending on the kinds of organisms in an area depends on how readily/ how much organic matter will be broken down. Medium sand - 0. 25 - 0. 5 mm. Coarse sand - 0. 5 - 1. 0 mm.
