Acute soil loss

Virtually total forest destruction in the first part of the 20th century and subsequent agriculture provoked erosion, soil slumping, wash off of soil and general soil impoverishment in the region.

As life starts in soil the ecosystem did not recover.

In the PPAP:

Soil profile from a hill in the PPAP →  →   →

it  shows the layer of ash from fires of the last century.

From 1 to 2 m of soil were washed

off from the hills as from the 1930s, like the region

the area experienced acute soil loss.

Burned lengua tree : this tree did not grow on the rock, it’s roots are normally covered quite deeply by soil. As lenguas grow slowly, it must have been an ancient tree. At least 2,5 m of soil were lost in this case.

Approximately 1.3 x 107 tons (calculation very conservative for 1 m layer lost) of soil were washed off from the hills to the valley floor only in the PPAP.

The erosion is visible on the hills, but not as bad as in other places of the region. The reforestation programme is helping with controlling erosion.

Erosion pattern

The soil became more than usual anthropogenic soil:

  compacted, low organic content, vulnerable to drought.

The soil lost it’s bacterial and microbiota

   component, and therefore its nutrient capacities.

There are virtually no earthworms in soil,

   their functions are partially replaced by ants, like in dry areas.

In winter the soil suffers from needle ice  →  →   →

Soil wash off changed the deltas of rivers and contours of

the lakes of the region. The delta of the largest river near

the PPAP was altered by the millions of tons of soil

the river carried.

Some soil restoration actions:

- Nutrient immobilisation via first colonisers in reforestation.

  1. -Complete removal of cattle and reduction of the number

       of horses to two led to elimination of soil microbiota

       deterioration by chemicals (antibiotics, worming,

       anti-pests, etc.) brought by them.

- Use of leaves mash for ice needles.

- Bacteria and microbes inoculation, using the science of Metagenomics - the microbes run the world.

- Avoiding the use of dangerous herbicides for the control of invasive species.

The positive aspect: The land has no potential that is in competition with restoration and conservation: the soil is too poor and eroded for agriculture, grazing cattle or sheep is too damaging for the land;  there are no trekking possibilities.

Further reading on regional soils : in  Publications.

Dry soil Patagonia
Forest fires Patagonia
Acute soil loss
Ice needles
Soil valley Leones
Soil Leones
Exposed rock Patagonia

PPAP: Bare rock -

result of soil loss

Delta Leones

Delta of Leones river

Exposed rock - result of soil loss

The PPAP: good example of destroyed ecosystem of the region and its inability to recuperate due to acute loss of soil →