1. PA Standards:
4.4.7.A– Describe how agricultural practices, the environment & availability of natural resources are related
4.5.7.A – Compare & contrast how people use natural resources in renewable and nonrenewable ways
4.5.7.C – Describe the wastes derived from using resources & how they are managed

2. 129. Chapter 4 – Land & Soil Resources (Sections 1 – 2)
Types of Land Use:
1) Agriculture – farming is possible on less than 1/3 of the Earth’s land
2) Development – construction of buildings, roads, etc. In the U.S. large areas continue to be developed each year
3) Mining – the removal of nonrenewable resources such as iron, copper or coal from the land; two kinds – a. strip mines (on the surface) b. underground mining (shafts dug deep)

3. Where PA Coal is Mined (Anthracite is expensive “hard coal”; Bituminous is cheaper “soft coal”)

5. Mine Fires Here and Around the World
Watch this video that explains what has happened in Centralia, PA over the last 50 years:

6. One of Many Other Mining Tragedies:
Knox Mine Disaster:

7. 130. Soil – a Valuable Resource
Soil is vital to the planet’s health because:
1) It contains the minerals and nutrients that plants need to grow
2) It absorbs and stores water for plants
3) As water percolates through soil it is filtered
4) Habitat for decomposers (worms, insects, & bacteria) that recycle the nutrients in dead organisms

8. 131. Structure of Soil Soil includes layers:
1) litter – dead leaves, grass, etc. on the surface
2) topsoil – rock particles, air space, and decaying plant and animal matter; plant roots draw their nutrients from this layer
3) subsoil – same as topsoil, but with less plant and animal matter
4) bedrock - bottom layer of rock

9. Soil Layers
Litter
Topsoil
Subsoil
Bedrock

10. 132. Problems of Poor Soil Management:
1) Erosion – removal of soil particles by wind, water or ice; occurs when bare soil is exposed
2) Nutrient Depletion – when more soil nutrients are used up than decomposers can replace; occurs when the same crop is planted year after year using up nutrients
3) Desertification – a loss of moisture and nutrients that creates desert-like conditions; occurs in areas with frequent droughts

11. 133. Solutions for Better Soil Management
1) Stop erosion by: a. never leaving soil bare (plant “green manure”) b. terrace hillside farms to reduce water runoff c. plant windbreaks of trees beside fields d. use of contour plowing along slopes
Green manure Terraced hillside Windbreak by field Contour plowing

12. (133. continued) You don’t need to write that
2) Restore soil nutrients by: a. sometimes leaving a field fallow (unplanted) but with crop stubble to decompose in it b. using crop rotation with different crops planted each year (that use different nutrients) c. planting a legume crop; these plants have nitrogen-fixing bacteria in their root nodules that put nitrogen into soil
Crop stubble in fallow field Crop rotation Legumes (beans, peas, etc)

13. (133. continued) You don’t need to write that
3) Avoid desertification by: a. not permitting overgrazing (down to bare soil) b. allowing a few trees to remain (to reduce erosion)

14. 134. The Problem of Waste Disposal:
Municipal solid waste can be buried in a sanitary landfill specially designed to contain toxic substances like “leachate” (water poisoned as it trickles through)

15. 135. Garbage can also be burned in special incinerators that use the heat energy to create electricity; however they’re expensive to build & create some solid waste (ash)

16. Operation of a Sanitary Landfill:

17. 136. Recycling is a way to reclaim raw materials for reuse:
Kitchen & yard waste – this can be recycled by composting; biodegradable waste is stacked outdoors where bacteria can decompose it; compost can then be used as garden fertilizer Metal – many metals can be melted and reused; this is cheaper than mining & processing new metal ores Glass – easily melted to make new containers or other products Paper – shredded paper is washed with chemicals to remove ink then mixed with water to form pulp; this is pressed & dried; recycled paper is not as smooth or strong Plastic – the raw material for plastic is resin leftover from refining petroleum (oil); recycling cuts down on our demand for more oil

18. Backyard Composting

19. Products Made from Recycled Metals:

20. Products made from Recycled Glass:

21. Products made from Recycled Paper:

22. Products made from Recycled Plastic:

23. 137. The “Three R’s”:
Reduce – reduce the amount of disposable products you use so less waste accumulates
Reuse – find a way to reuse items rather than throw them away
Recycle – always recycle items when possible

24. How to Grow More Food Without Any Soil: Hydroponic Farming

25. Photo credits
Skeletal remains:
Soil Layers:

26. Photo Credits (cont’d)
Windbreak:
Green manure:

27. Photo Credits (cont’d)
Terracing:
Contour Plowing: