Soil and Site Evaluation

Transcription

1 Soil and Site Evaluation Getting the Dirt on Soils By Dr. David Lindbo, NCSU Cooperate Extension 1

2 Acknowledgement This work was supported [in part] by the National Decentralized Water Resources Capacity Development Project with funding provided by the U.S. Environmental Protection Agency through a Cooperative Agreement (EPA No. CR ) with Washington University in St. Louis. The results have not been reviewed by EPA or Washington University in St. Louis. The views expressed in this presentation are solely those of NCSU, and University of Arkansas and EPA and Washington University in St. Louis do not endorse any products or commercial services mentioned in the presentation. 2

3 What are 4 things we cannot live without? 3

4 AIR 4

5 SUNLIGHT 5

6 WATER 6

7 SOIL 7

8 Does Soil = Dirt? What is a soil? What does it mean to you? Does it have and special meaning to you? Before answering these questions consider what you see in the soil. 8

9 NO Dirt is the stuff under your fingernails or what you sweep off the floor What is a soil? What does it mean to you? Does it have and special meaning to you? Before answering these questions consider what you see in the soil. 9

10 Soil Facts Topsoil is the most productive layer Five tons of topsoil spread over an acre is only as thick as a dime Soil supplies water and nutrients for plants Most of our food comes from soil It can take more than 500 years to form one inch of topsoil What is a soil? What does it mean to you? Does it have and special meaning to you? Before answering these questions consider what you see in the soil. 10

11 Soil Facts An acre of corn gives off 4000 gallons of water a day in evaporation Soil Scientist have identified over 70,000 different soils in the U. S. Erosion of soil clogs rivers and lakes Soil influences the life spans of roads What is a soil? What does it mean to you? Does it have and special meaning to you? Before answering these questions consider what you see in the soil. 11

12 Soil Facts Soil is alive. 1 gram of soil contains up to a billion bacteria There many thousands of types of bacteria in soil 15 tons of soil per acre pass through earthworms each year What is a soil? What does it mean to you? Does it have and special meaning to you? Before answering these questions consider what you see in the soil. 12

13 Soil Facts Soil is the largest single wastewater treatment unit in North Carolina 3.5 million North Carolinians rely on soil to treat and disperse wastewater Soil is extremely effective at wastewater treatment Best of all What is a soil? What does it mean to you? Does it have and special meaning to you? Before answering these questions consider what you see in the soil. 13

14 Soil makes great mud pies and is just plain fun! 14

15 What is a soil? And why do we care? What is a soil? What does it mean to you? Does it have and special meaning to you? Before answering these questions consider what you see in the soil. 15

16 A soil is a porous natural body of mineral, air, water and organic matter that changes, or has changed, in response to climate, topography, time, and organisms. This is the text book definition. Basically, it says that soils are dynamic and reflect the conditions that they formed under. Because they do reflect the environment in which they formed we can use their morphology to understand more about the environment. Thus soils can be like a very smart canary in the coal mine if we know how to interpret their song. 16

17 Soil Science Society of America soil: (i) the unconsolidated mineral or organic material on the immediate surface of the earth that serves as a natural medium for the growth of land plants. 17

18 Rule.1935 (41) Soil Soil means the naturally occurring body of porous mineral and organic materials on the land surface. Soil is composed of sand-, siltand clay-sized particles that are mixed with varying amounts of larger fragments and some organic material. Soil contains less than 50% of its volume as rock, saprolite, or coarse-earth fraction (mineral particle greater than 2 mm). The upper limit of the soil is the land surface, and its lower limit is rock, saprolite, or other parent materials. 18

19 Soil Definition Soil means the naturally occurring body of porous mineral and organic materials on the land surface. The upper limit of the soil is the land surface, and its lower limit is rock. 19

20 What is a soil? And why do we care? What is a soil? What does it mean to you? Does it have and special meaning to you? Before answering these questions consider what you see in the soil. 20

21 Importance of Soil to On-site Wastewater Biological treatment Chemical treatment Physical treatment Dispersal Just as in a wastewater treatment plant soils treat the wastewater I much the same way. 21

22 How does soil treat wastewater? Well Groundwater Aerobic soil Aerobic soil is needed to treat remove pathogens and disperse the treated wastewater back into the environment 22

23 What is a soil? And why do we care? What is a soil? What does it mean to you? Does it have and special meaning to you? Before answering these questions consider what you see in the soil. 23

24 What is soil made of? Soil is composed of minerals, organic matter, air, water 24

25 Solid material Soil is made of: Minerals Dead organic material Living organic material Pore space Air Water Soil has two major components that can be subdivide into 5 five components overall. Their relative amounts will alter the properties of the soil but no one is more important than another. 25

26 What does the site evaluator need to know? 26

27 Next lectures Parent Material Topography Soil Texture Soil Structure Soil Consistence Soil Color Profile Description Site Evaluation Determination of LTAR Soil Survey 27

28 Summary Soils are the living skin of the earth Soils treat wastewater Soils are complex SOILS SUSTAIN LIFE 28