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www.GOALias.blogspot.comDropperFilter paperFig. 9.7 Absorption of water in the soilFunnelBeakerPour water all over the soil. Keep pouringwater till it starts dripping. Subtract theamount of water left in the measuringcylinder from the amount you startedwith. This is the amount of waterretained by the soil. Record your resultsin your notebook in the followingmanner:Weight of soil = 50gInitial volume of water in themeasuring cylinder = U mLFinal volume of water in themeasuring cylinder = V mLVolume of water absorbed by the soil= (U – V) mLWeight of water absorbed by the soil= (U – V) g(1 mL of water has weight equal to 1 g)percentage of water absorbed(U - V)= 10050Repeat this activity with different soilsamples. Would you get the same resultsfor all the samples? Discuss the resultswith your friends and answer thefollowing question:• Which soil would have the highestpercolation rate?• Which soil would have the lowestpercolation rate?• Boojho heard from his neighbourerthat 8–10 days after the rain, the levelof water in a pond or well rises. Whichtype of soil will allow water to reacha well faster and in greater amount?• Which type of soil retains the highestamount of water and which retainsthe least?• Can you suggest any method to letmore rain water percolate and reachthe water underground?9.7 S9.7 SOILAND CROPSDifferent types of soils are found indifferent parts of India. In some partsthere is clayey soil, in some parts thereis loamy soil while in some other partsthere is sandy soil.Soil is affected by wind, rainfall,temperature, light and humidity. Theseare some important climatic factorswhich affect the soil profile and bringchanges in the soil structure. TheGram (g) and kilogram (kg) are actually units of mass. A mass of 1 gram weighs 1 gram weight,and a mass of 1 kilogram weighs 1 kilogram weight. However, in daily life, and in commerce andindustry, the distinction between gram and gram weight is generally omitted.102SCIENCE