*Level 9 Guiding Question: How do water and soil interact?
Soils can process and hold considerable amount of water. They can take in water, and will keep doing so until they are full, or until the rate at which they can transmit water into and through the pores is exceeded. Some of this water will steadily drain through the soil (via gravity) and end up in the waterways and streams, but much of it will be retained despite the influence of gravity. Much of this retained water can be used by plants and other organisms, thus contributing to land productivity and soil health.Pores (the spaces that exist between soil particles) provide for the passage and/or retention of gases and moisture within the soil profile. The soil's ability to retain water is strongly related to particle size; water molecules hold more tightly to the fine particles of a clay soil than to coarser particles of a sandy soil, so clays generally retain more water. Conversely, sands provide easier passage or transmission of water through the profile. Clay type, organic, and soil structure also influence soil water retention.
The maximum amount of water that a given soil can retain is called field capacity, whereas a soil so dry that plants cannot liberate the remaining moisture from the soil particles is said to be at wilting point. Available water is that which the plants can utilize from the soil within the range between field capacity and wilting point. Roughly speaking for agriculture (top layer soil), soil is 25% water , 25% air, 45% mineral, 5% other; water varies widely from about 1% to 90% due to several retention and drainage properties of a given soil.
The maximum amount of water that a given soil can retain is called field capacity, whereas a soil so dry that plants cannot liberate the remaining moisture from the soil particles is said to be at wilting point. Available water is that which the plants can utilize from the soil within the range between field capacity and wilting point. Roughly speaking for agriculture (top layer soil), soil is 25% water , 25% air, 45% mineral, 5% other; water varies widely from about 1% to 90% due to several retention and drainage properties of a given soil.
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*Level 9 Investigation: Water and soil interactions
*Read the above presentation and after you can read it please complete the practice assignment to see how much you have retained.
Soil and Water Interactions
Level 9 Videos: Water Retention
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*Level 9 Elaborate: Available Water
Before you complete this assignment listen to the VDO entitled, "Soil Water Potential" and read the presentation under the "Investigation" heading
*Level 9 Review: How do soil and water react? Making Infographics
Your assignment is to make an Infographic that contains the following criteria: the topic has to do with Soil Water (i.e. water retention, Field Capacity/Wilting Point, Soil water potential, Conversation Practices, Bulk Density/Porosity. Use at least three colors, four graphics, attribution,
two different font types and or sizes, 3 pieces of information or stats and must be appealing to the eye. You may use any free online infographic app (see the VDO below about how to use one such source (https://www.easel.ly), if you are artist create it yourself. Please either send it via email to your instructor or if you create it yourself scan or take a picture of it and submit via email.
two different font types and or sizes, 3 pieces of information or stats and must be appealing to the eye. You may use any free online infographic app (see the VDO below about how to use one such source (https://www.easel.ly), if you are artist create it yourself. Please either send it via email to your instructor or if you create it yourself scan or take a picture of it and submit via email.
Above are samples of student work.
Level 9 Summary: Unit Test
Check back later for the Unit Test post!