Monday, June 25, 2012

My Favourite Soil: Arenosol aka Kalahari Desert Soil

This months MFS comes from Nina Swiegelaar. Nina is a winemaker turned soil scientist. She has a passion for Kalahari soils and sustainable solutions for agricultural industries. 



I think I have always been destined to have a job or the type of life where I can get my hands really dirty. I come from an agricultural background and as far back as I can remember, I have always felt a very strong pull towards our “land.” There is a very childlike feeling of happiness when I get to push my fingers into the soil and feel it go in under my nails. I suppose I am not your typical girl.


My favourite soil is the Kalahari desert soil. There is no real scientific basis for my choice of favourite soil, seeing as the Kalahari soils are not overly fertile and poor for plant growth, have low organic matter content and in some places tend to be toxically alkaline (pH > 7). Kalahari desert soils are aeolian soils, that are formed by wind, and have a beautiful red colour. The Kalahari desert soils are classified as Arenosols and they cover large areas of Africa and Southern Africa.

Map of the Kalahari region (CC image from Wikispaces Group-Ethnographies)

These soils contain no more that 35% rock fragments in the surface 100mm layer. In the figure below the soil profile and the very characteristic red colour can be observed.

Soil sampling
Sampling Arenosol, or Kalahari desert soil (CC by K.Caylor)

So why is this my favourite soil type? Maybe it is because some of the world’s best grapes are produced on some of these red soils? Or maybe it is just the magnetic red colour that mesmerize me, or maybe the Kalahari desert soil is my favourite soil because it is from the land I come from? Whatever the reason, this is my favourite soil type and as the saying of the Kalahari desert people go: “Once that red sand has gotten stuck under your finger nails, you will forever want to return to this soil.”

2 comments:

  1. I know what you mean about desert type soils. And being an Aussie you'd be attracted to iron rich red soils low on phosporus.

    I just wrote a piece on Mesquite Dune Experiment on my Earth's Internet" blog which also has practical applications towards Acacia habitats as well. I miss the deserts.

    We've had nothing but cold and rain here and temps around 14 celsius which doesn't work at all for me for a summertime.

    Kevin


    -

    ReplyDelete