Geography elss

• Crop irrigation diverts surface water from rivers and groundwater to cultivated land. Some water is absorbed by plants and released by transpirstion, but most is lost to wvaporation and soil drainage.
• Interception by annual crops is less than in forests and grassland. this means there is more runoff, infiltration and the land becomes more saturated.
• Ploughing increases evaporation and soil moisture loss. Furrows act as drainage channels increasing runoff and soil erosion.
• Artificial surfaces allow little to no infiltration. drainage systems are created to remove surface water causing it to rapidly flow into streams and rivers.
• Urban areas have 55% runoff compared to10% in natural ground over.
• Urbanisation encroaches onto floodplains which reduces water storage capacity and increases river flow and flood risk.