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Forests for Water

There is this common misconception that forests demand a lot of water and that in areas where droughts are experienced, the planting of trees should be avoided.

There is truth in that where the monoculture of invasive Australian Gum and Acacia and Mediterranean Pine trees are concerned, but the story is different in relation to pristine eco-forest systems indigenous to the Cape. Indigenous trees “drink” water as well of course, but they also provide water-related services to the land.

Pristine indigenous forests in the Cape are shady and multi-layered. They capture the Sun’s energy and –hence- cool the place down. Cape forests remain much cooler during the day-time than land covered with bush or sparse vegetation. This reduces evaporation from the soil.

Forests capture clouds, fog and other atmospheric moisture (of which at the coast, much originates from the ocean) and as such enhance water retention, which is one of the factors that contribute to rain.

But forests also contribute to water retention of the land. Tree roots do not only provide upward flow of water but also downward. The water captured by forest that is not immediately needed by the trees, are –as it were- injected deep into the soil. The roots of the trees infiltrate deep and wide into the soil and in this manner add to ground-water re-charge.

Especially in areas with seasonal rains, such as the Cape, this water retention capacity of forests slows down the amount of water flowing downstream during winter when water is plenty and –as such- contributing to water-flow after the rain-season, when the riverine and catchment areas need it more.

In one of the reforestation sides of the South African Reforestation Trust (The “WPO Plant a Forest Program” is part of this Trust), the stream did widen, meandered more and did flow slower after rehabilitation through reforestation resulting in increased water retention of the land and slower run-off to the ocean.

Indigenous forest-systems are intimately linked to rainfall and water availability.

And the above is not saying anything about the forest’s capacity to improve the quality of the water, to produce clean air and rich soil and store carbon, prevent erosion, desertification and floods, regulate the temperature of the earth and help maintain the Cape’s biodiversity. Not least of all, forests create a sanctuary for man.

Forests provide essential services for mankind.