1. SOIL
APES NOTES

2. The ROCK CYCLE IGNEOUS ROCK = granite, pumice, basalt, obsidian
METAMORPHIC ROCK = marble, schist, slate, quartz
SEDIMENTARY ROCK = conglomerate, shale, limestone, sandstone

3. MECHANICAL WEATHERING
*PRESSURE FROM WIND AND WATER
*FREEZING AND THAWING
*ANIMAL ACTIONS
*PLANT GROWTH

4. CHEMICAL WEATHERING WATER (H2O) -water dissolves substances
OXYGEN (O2) - it will combine with iron to cause rust
CARBON DIOXIDE (CO2) – combines with water to form an acidic solution
LIVING ORGANISMS – they secrete/excrete chemicals that can change the pH
ACID RAIN – as a result of atmospheric pollution
LICHEN GROWING ON ROCK

5. What is soil?
Soil is a mixture of different materials:
Weather rock particles
Decayed remains of organisms
Water
Air
Living organisms and their excretions

6. SOIL HORIZONS https://www.youtube.com/watch?v=6ZibUOYUMbE
(the Parent Material )

7. ESSENTIAL SOIL NUTRIENTS

8. FERTILIZERS FERTILIZERS : substances that contain essential nutrients
* INORGANIC FERTILIZERS: synthetically manufactured mineral supplements
* ORGANIC FERTILIZERS: from the remains or wastes of organisms
(manure, crop residues, fresh vegetation)
(Compost = produced when decomposers break down organic matter)
OVER-APPLICATION OF FERTILIZERS:
*over applying inorganic fertilizers can pollute the soil
*runoff causes eutrophication (over abundance of nutrients ) in water systems
*over abundance of Nitrates leach through the soil and contaminate groundwater

9. FACTORS OF SOIL
Infiltration: the downward movement of water through the pores of soil
Leaching: dissolving of minerals and organic matter in upper layers carrying them to lower layers.
Soil Classification: based on color, texture, nutrient content, and infiltration

10. SOIL COLOR SOIL COLOR indicates its composition and fertility
* Black or dark Brown = soil will be rich in organic matter
* Pale gray or white = contains little or no organic matter and indicates leaching
(mostly calcite)
* Red = indicates iron content

11. TYPES OF SOIL
CLAY = consist of very small particles, (less than .002 mm in diameter) Clay particles adhere to each other and is more compact than other soils (STICKY FEEL)
SILT = medium size particles ( mm in diameter) (SMOOTH/POWDERY FEEL)
SAND = large size particles, ( mm in diameter), Sand will consist of larger pores which means low water retention (GRITTY FEEL )
Gravel layer

12. PROPERTIES OF SOIL SAND SILT CLAY DRAINAGE HIGH GOOD LOW AERATION
FERTILITY
WATER HOLDING CAPACITY

13. LOAM
LOAM = SOIL WITH AN EVEN MIXTURE OF THE THREE TYPES OF SOIL ( CLAY, SILT, SAND) and HUMUS (dead, organic matter)
SILTY SOILS WITH MEDIUM SIZE PORES, OR LOAMY SOILS WITH MIXTURES OF PORE SIZES ARE BEST FOR PLANT GROWTH AND CROP AGRICULTURE

14. SOIL TEXTURE TRIANGLE 34 % Sand Texture = 33 % Silt CLAY LOAM
Sand + Silt + Clay = 100%
34 % Sand
Texture =
CLAY LOAM
33 % Silt
33 % Clay

15. Texture by Feel

16. EROSION EROSION = the movement of soil by wind or water
* removes topsoil
* occurs when vegetation is absent
* occurs easily on steep slopes
EROSION INCREASES THROUGH:
* excessive tilling
* overgrazing
* clearing forests
TYPES OF EROSION:
*SPLASH
*SHEET
*RILL
*GULLY
SPLASH EROSION
RILL EROSION
GULLY EROSION

17. DESERTIFICATION
RESULTS FROM: erosion, soil compaction, vegetation removal, overgrazing, salinization, climate change,
depletion of water sources
Dust Bowl:
* in the 1930’s , settlers in Oklahoma, Texas, Kansas, New Mexico, Colorado
over grew wheat, overgrazed cattle, removed excessive vegetation which led to soil degradation
*a drought in the 1930’s made conditions worse

18. FACTS ABOUT AGRICULTURE:
AGRICULTURE = practice of raising crops and livestock for human use and consumption
CROPLAND = land used to raise plants for human use
RANGELAND/PASTURE = land used for grazing livestock
FACTS ABOUT AGRICULTURE:
*38% of Earth’s land surface is devoted to agriculture
*mismanaged agriculture can result in soil degradation which leads to desertification, diminishes biodiversity, and pollutes soil
*Land suitable for farming is running out
*Coupled with rapid population, some believe that the future of
agriculture is in crisis

19. TYPES OF AGRICULTURE * SUBSISTENCE AGRICULTURE = family farming
* INDUSTRIALIZED AGRICULTURE= using large-scale mechanization, fossil
fuels, irrigation, fertilizers, and pesticides to boost yields
* MONOCULTURES = uniform planting of a single crop
Industrialized
Monoculture
Subsistence

20. SOIL CONSERVATION
CROP ROTATION = alternating the crops grown from one season to the next
CONTOUR FARMING = plowing furrows sideways across a hillside, perpendicular to its slope
TERRACING = level platforms are cut into steep hillsides (looks like a “staircase”)
INTERCROPPING = planting different types of crops in alternating bands
SHELTERBELT/WINDBREAK= rows of trees or other tall plants that are planted along the edges of fields to slow the wind
ALLEY CROPPING = using both shelterbelts and intercropping
REDUCED or NO TILLAGE = furrows are cut in the soil, a seed is dropped in and the furrow is closed
DRIP IRRIGATION = watering that targets water directly to the plants

21. Irrigation vs Drip Irrigation

22. SOIL CONSERVATION PROGRAMS
FOOD SECURITY ACT OF 1985 : farmers that adopt soil conservation plan receive price supports and other benefits
CONSERVATION RESERVE PROGRAM (1985) : farmers are paid to place highly erodible land into conservation reserves with trees and grasses planted instead of crops
FEDRAL AGRICULTURAL IMPROVEMENT ACT (1996) : also known as the “Freedom to Farm Act” : aimed to reduce government influence over farm products and to promote conservation practices in agriculture. It created the Environmental Quality Incentive Program and Natural Resource Conservation Foundation
FOOD AND AGRICULTURE ORGANIZATION (FAO): the international, United Nation’s main agricultural program