On man-made slopes, soil dries out from the top downwards. Upper soil layers are already drained and completely dry. Water runs off from the forest above the slope through broken pores in the slope. This is a clear example of the way we are gradually draining our forests - irreplaceable reservoirs of drinking water for fauna and flora on our planet.
Mountains and hills slashed by forest roads and man-made slopes above them are thus sentenced to gradual draining, with fertile soil being washed away and all living organisms dying. Such hills are unable to retain one drop of water – the water which will be sorely missed by the slope as far as 100 m above the forest road and by the entire forest alike. Regardless of whether we are talking about coniferous or broad-leaved forests, broken pores will dry any of them.And we go further, slashing even the areas where logging is not done due to the steepness of the slopes. Road and highway construction sites illustrate this perfectly – we do not even think about the retaining of water in soil here. Instead, we are doing our best to get rid of it as quickly as possible, forming ideal conditions for the water to run off.
“Simulation of rain above a man-made slope” - Measurements
The experiment carried out at a number of places in forests has proven that man-made slopes contribute to floods. A slope (similar to the ones left at the road building sites after the construction works are completed) was created in a hilly terrain and we simulated rain in the area above this slope. The water which would normally soak into the ground through capillaries was discharged through the broken capillaries in a man-made slope instead, thus draining the forest above the slope. As much as 71% of the total volume of simulated precipitation was discharged.