Soil-Garden Group ID: 1004 Team Members SiowZiHao (Group Leader) 1A2 Regan Tan 1A2 RavnTeo 1A2 Richie Chua 1A2
What we will be covering in this powerpoint • Some Information on Rain Gardens • Hypothesis and objectives • Materials used • Experimental set-up • Variables • Limitations • Steps to carry out experiment • Results • Conclusion • Reflections • Sources
So, what is a Rain Garden? • The rain garden is a shallow depression that is usually positioned near a runoff source like a downspout, driveway, sump pump or roof. • It is positioned there to slow down the rush of water from these hard surfaces. • The rain garden holds the water for a while before allowing the water to infiltrate the ground naturally. • This will help to prevent floods as • water could not be retained on the • surface of the ground.
More about Rain Gardens • Native plants are usually planted on rain gardens as they can survive well without fertilizers. • These native plants have elaborate root systems that create channels into the soil, causing it to absorb more water readily.
So, what are the advantages of a rain garden? • This rain gardens improve water quality as it filters the runoff from the roof, driveway etc. , recharging the ground water. • Rain gardens not only help to ease floods, filter water, rain gardens can also be used to beautify the environment. • But, for these to happen, which soil can cause these to happen? • After research, we came up with • a few points.
Just to Recap The Purpose of our experiment To find out which soil is retains the least amount of water Hypothesis of our experiment Sandy soil retains the least amount of water.
Items that we used in the experiment 3 Soils: clay, humus, sandy 10 – 1.5 litres coke bottles 1 measuring cylinder 1 stopwatch 3 beakers 1 laboratory thermometer 10 filter cloth (tap filters) 10 filter funnels 1 retort stand 1 tripod stand
Our experimental set-up 28 degrees Celsius (Air-conditioner on) Beaker where water will be poured from Level at which soil is filled up to Coke bottle Mouth of bottle covered with filter cloth \ Soil Filter funnel Retort stand to hold coke bottle Beaker for collection of water
Control set-up 28 degrees celcius (Air-conditioner on) Beaker where water will be poured from Level at which soil is filled up to Coke bottle Mouth of bottle covered with filter cloth \ Soil Filter funnel Retort stand to hold coke bottle Beaker for collection of water
Variables • Independent variable: • Type of soil • Dependent variable: • Amount of water that will pass through soil • Controlled variables: • Size of hole in the container containing soil • Amount of water poured • Amount of soil • Size of containers • Duration of experiment
Limitations of this experiment • The temperature of the surroundings (Science Lab) • The humidity of the room • Angle at which the water is being • Temperature of soil
Procedures to carry out the experiment Firstly, label 3 - 1.5 Coke bottles with A, B and C. Next, fill A, B and C with sandy soil, clayey soil and humus soil respectively Pour 200 ml of water through the bottom of the A Start the stopwatch at the same time. Stop after 2 minutes and record the amount of water in the beaker Repeat steps 3-5 two more times for A and 3 times each for B and C.
Our results std error Average Std deviation Reading 1 Reading 2 Reading 3 T-test 80.0ml 79.0ml 81.0ml 80.0ml 0.58 1.00 Sandy 0.004 Clayey 62.0ml 60.0ml 59.0ml 60.5ml 1.53 0.88 0.002 38.0ml 33.0ml 35.0ml 35.5ml 2.52 0.001 1.46 Humus 150 ml ( all the water flowed through before 2 minutes) Control
LEGEND - Humus - Clayey soil - Sandy soil Graph 150ml 140ml 150ml 130ml 120ml - Control 100ml 110ml 90ml 81ml 80ml 79ml 80ml 80ml 70ml 62ml 60ml 60.5ml 59ml 60ml 50ml 38ml 35.5ml 40ml 33ml 35ml 30 ml 20 ml 10 ml 0 1st attempt average 3rd attempt 2nd attempt
Conclusion From our experiment, we found out that water flows through Sandy soil at the highest rate as compared to the other soil types. Therefore, Sandy soil should be used at a greatest amount than humus and clayey soil for the building of a rain garden. Sandy soil is not used used only as there is hardly any water and nutrients in the soil, thus plants will not grow well.
Reflections We learnt many things during the process. One of the valuable lessons is that teamwork is crucial for a project to be successful. Teamwork is also needed to make our own experimental set-up. Without teamwork, I doubt that we would have finished our experimental set-up in time.
Conclusion A little clayey soil is needed so the plants would not behave as if they were in a clay-bottomed pot and stay at the top layer soil and as a result, water would not move through the soil as fast as it should be. A bit of humus is needed to provide some nutrients for the plants as sandy soil hardly contain any nutrients. Although this 2 soils retain a lot of water, the rate of infiltration will not be greatly affected.
Recommendation After our experiment, we would recommend that the government should build rain gardens and should plant more trees around areas prone to floods. These will probably reduce the impact of floods or even prevent floods as water could not be retained. The government also should not worry about problems of mosquitoes breeding in the rain gardens as the water should infiltrate the soil naturally by the end of 2 days.
Sources http://nricd.org/Lesson_7_Experiment.pdf http://www.wisegeek.com/what-is-soil-drainage.htm http://www.for-wild.org/download/rainclay/rainclay.html http://organicgardening.about.com/od/soil/a/improveclaysoil.htm http://www.rain.org/global-garden/soil-types-and-testing.htm http://ag.arizona.edu/turf/tips1095.html http://www.funsci.com/fun3_en/exper1/exper1.htm http://school.discoveryeducation.com/schooladventures/soil/name_soil.html http://school.discoveryeducation.com/schooladventures/soil/name_soil.html