EES 1080 Lecture Notes - Lecture 3: Soil Retrogression And Degradation, Soil Fertility, Parent Material

• School: University of Iowa
• Department: Earth & Environmental Sciences
• Course: EES 1080
• Professor: Dorale

Document Summary

Case study: no-till agriculture in iowa: repeated plowing and planting damage soil, no-till farming, benefits the soil, saves time and money, other conservation measures, careful use of fertilizers, preventing erosion, retiring fragile soils, production is not lowered. Millions of acres of cropland are lost each year: we lose 5-7 million ha (12-17 million acres) of productive cropland/year. Soil degradation has many causes: soil degradation a decline in quality and productivity, from deforestation, agriculture, overgrazing, over the past 50 years, soil degradation has reduced global grain production by 13% Agriculture arose 10,000 years ago: different cultures independently invented agriculture, the earliest plant and animal domestication is from the (cid:498)fertile crescent(cid:499) of the middle east, wheat, barely, rye, peas, lentils, onions, goats, sheep. Soils that are best for plant growth and agriculture: silty soils with medium sized pores, loamy soils with mixtures of pore sizes.