Populatipon and Environment Soil Flashcards
define soil erosion.
the wearing away of soil mainly the topsoil where all the nutrients and structure for agricultural activity is.
what are soil problems that can occur?
-structural detererioration
-salinisation
-waterlogging
-desertification
what is structural deterioration?
when the structure of the soil is lost, especially the pores between the soil particles that contain air
why does structural deterioration occur?
-Livestock trample on the soil
-removal of crops and plants as roots give soil structure
-farming machinery can cause soil compaction
what is waterlogging?
when soil becomes oversaturated with water.
why does waterlogging occur?
via heavy rainfall or flooding or too much irrigation.
effects of waterlogging.
-water leaches away nutrients
-water lowers temperature of soil which slows photosynthesis
-limited oxygen supply
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what is salinisation?
-increased levels of salt in soil which occurs due to saline water rising ti the surface of soil and being evaporated and then leaving salt crystals
which factors cause salinisation to occur?
-high temperatures
-groundwater levels rising
-irrigation-water contains salt
what are the effects of salinisation?
-salt toxic for plants
-may break up natural soil structure
what are some ways to manage soil problems?
-contour ploughing
-crop rotation
-drip irrigation
explain contour ploughing.
ploughing across a slop rather than down to stop fast run-off
explain crop rotation.
planting more than one type of crop in an agricultural area to stop nutrients being over exploited.
explain drip irrigation
a method used to stop over watering as it waters plants efficiently and prevent waterlogging
