Environmental Sciences

1. Environmental Sciences

2. Water Properties • Water has been called the universal solvent because as a material it dissolves or otherwise changes most other materials • The water cycle is the cycling of water between water sources, atmosphere, and surface areas

3. Water cycle • Precipitation is the release of moisture as rain or snow • Evaporation is the process during the water cycle when water changes from a liquid to a gaseous state

4. Water Cycle

5. Water properties • Types of water: • Capillary water is water that plant roots can absorb or take up • Free water (gravitational) is water that drains out of a soil after it has been wet

6. Water properties • Permeability is the rate of movement of air and water through the soil • Saturation is the special condition that exists when water is added until all the spaces or pores are filled

7. Saturation • Usually happens after heavy rainfall over a period of time • Example: two or more inches of rainfall during a relatively short period of time (perhaps 3 hours)

8. Soil Horizon • There are several soil horizons and we are going to focus on three

9. Soil Horizon • A • Topsoil • Dark brown to yellow • Generally loose, crumbly, well broken up • Zone of leaching • Usually contains more organic matter

10. Soil Horizon • B • Subsoil • Brown, red, yellow, or gray • Generally larger chunks, may be dense or crumbly, can be cement like • Zone of accumulation

11. Soil Horizon • C • Parent material Weathering of parent material or rock

12. Surface and subsurface characteristics • Soil texture refers to the size of soil particles • A. Sand – largest soil particle in soil • 1. Have a hard time holding water for good plant growth • 2. Individual particles can be seen with naked eye

13. Soil Texture • B. Silt – intermediate size soil particles that can’t be seen with the naked eye

14. Soil Texture • C. Clay – smallest soil particle • Clayey soils hold lots of water but may be airtight, infertile for root growth, and associated with wet soils.

15. Soil Structure • Refers to the way soil particles cling together to form soil units or aggregates, while leaving pore space to store air, water, nutrients, and allow root penetration.

16. Types of Soil Structure • 1. Single – grain is associated with sandy soil • 2. Granular – particles cling together to form rounded units (aggregates) • 3. Blocky – particles cling together in angular units (aggregates) • Typical of soils with high clay content

17. Soil classifications • Land capability maps are based on the physical, chemical, and topographical aspects of the land

18. Soil classifications • Are designated by Roman numerals I through VIII • Class I and II land is the best for the most intensive cultivation of field crops • Class VII land is very steep sloping and best used for planting trees • Class VIII land is best suited for wildlife and recreation

19. Soil conservation and enhancement • Two types of erosion • Sheet • Gully • “ No-till” is a cropping technique used to reduce soil erosion • Crops are planted directly into the residue of a previous crop without plowing or disking • Very effective erosion control

20. Soil conservation and enhancement • Conventional tillage- uses tillage system that disturbs the soil surface by plowing, disking, and/or harrowing • Conservation tillage- intermediate tillage system between conventional and no-till • Use fertilizer to add nutrients to the soil

21. Soil conservation and enhancement • Use lime as an amendment to raise soil pH • Increases availability of nutrients • Example: if soil pH is 5.5, lime may be added to raise soil pH to a more acceptable 7.0 level

22. Careers for various education levels • Bachelor’s degree would be the minimum for: • Soil scientist- classify soil according to the most appropriate use • Soil conservation- assist landowners in implementing best land use practices • Wildlife biologist- do research on habitat and wildlife as part of career

23. Careers for various education levels • Less than 4 year college degree: • Soil technician- uses soil auger/ soil tube to take soil samples and do field work • Wildlife technician- works in the field tagging animals and gathering data

24. Forestry and It’s Importance in the US and the Environment

25. Softwoods- needle type evergreens • Southern pine • Includes loblolly, longleaf, short leaf and slash pine. • Most commonly used for pulpwood and plywood http://www.state.sc.us/forest/reftree.htm - contents

26. Loblolly pine

27. Longleaf pine

28. Short leaf pine

29. Slash pine

30. Frazier fir • Used for commercial Christmas tree production • Grown in the mountains of NC http://www.nelsonstrees.com/shop.asp

31. Douglas fir • Perhaps the most important species of tree in the US • Use for construction lumber and plywood http://www.orst.edu/instruct/for241/con/spp/dgfspp.html

32. Hardwoods- deciduous trees • Ash: • Used for handles, baseball bats • Resembles oak and has a high resistance to shock http://www.magdalin.com/herbal/plants_pages/a/ash_tree.htm

33. Birch • Used for furniture, plywood, paneling • Made into veneer http://www.state.sc.us/forest/tidtsim.htm#rb

34. Oak (white and red) • Flooring, furniture, fencing • Very strong wood http://www.state.sc.us/forest/tidlob.htm

35. Replacing Trees That Have Been Harvested • The least expensive method to replace harvested trees is “natural seeding” • A surer method of replacing harvested trees is to plant seedlings

36. Managing Growing Timber • A “Prescribed burn” is used to reduce the risk of wild fires by eliminating forest litter • “Prescribed thinning” is recommended to remove some trees when competition slows the growth of all trees

37. Harvesting timber • “Selection cutting” is the harvesting method recommended in a mixed forest of trees consisting of different ages and species • “Clear cutting” is a system of cutting timber where all of the trees in an area are removed

38. Careers in Equipment in Forestry • Foresters provide assistance in managing forest for the family as well as the commercial grower • Foresters may recommend reseeding a harvested tract with the most appropriate seedlings

39. Careers in Equipment in Forestry • Foresters may use or recommend the following tools: • Increment borer to determine the age of trees within a stand • Planting bar for planting seedlings • Tree scale stick to estimate tree volume • Tree tape: circumference

40. Tools Increment borer http://www.pfmt.org/inventories/increment_borer.htm Planting bar procedure http://www.extension.umn.edu/distribution/naturalresources/DD0481.html#pm

41. Careers in Equipment in Forestry • Timber cruisers are hired by private landowners and companies to estimate the tree volume on a tract of land • Do outdoor work that requires physical stamina • Requires a high school diploma and special training in estimating tree volume

42. Wildlife Management Practices and It’s Relationship to Environmental Sciences

43. Wildlife Management Practices • Usually a by-product of the family operation • Suitable habitat and food are essential to increase the number of wildlife on a farm • Habitat: brush piles • Food: crop residue

44. Wildlife Management Practices • Proper wildlife management includes managed hunting and fishing • Removes excess wildlife that would otherwise be lost due to natural causes • Prevents overpopulation, which results in malnutrition, disease and a reduction in reproduction which will result in decreased wildlife population

45. Wildlife Management Practices • Carrying capacity is the number of wildlife each habitat can support throughout the year • Managed hunting and fishing will help maintain • More wildlife than the habitat can support will result in problems

46. More wildlife than habitat can support • Wildlife are affected by malnutrition, disease, and a reduction in the reproductive cycle • Habitat quality goes down. Example, water quality of a stream with a carrying capacity of 20 fish will decrease if 50 fish are in the stream

47. Careers in Wildlife Management • Ecologists study the effects of the environment on animal life • Wildlife biologists advise government agencies in establishing fish/game laws and habitat improvement programs

48. Careers in Wildlife Management • Game warden (wildlife officer) • Enforces hunting and fishing regulations as means of wildlife management • Should enjoy working outdoors • In NC- government employee under NC Wildlife Commission • NC Wildlife Commission is responsible for controlling the harvest of wildlife

49. Aquacultures Importance to Environmental Science

50. Aquaculture and Management of Fish Production • Hatcheries supply fry or larvae to units for fingerling production • Cage culture contains the aquatic animals or plants in a small area of a pond • Fish can be monitored better for growth rates and feeding purposes • Water quality must be monitored to insure that the fish are not stressed or killed since fish cannot move to other sections of the pond during stressful weather conditions