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They slashed and burned forests in fertile regions. Boreal forests are nothing like that. “ Soils in the boreal forest are typically podzols (from the Russian

by graeme 6y ago

They slashed and burned forests in fertile regions. Boreal forests are nothing like that. “ Soils in the boreal forest are typically podzols (from the Russian word for “ash”), gray soils that are thin, acidic, and poor in nutrients. These soils lie beneath a mat of coniferous tree needles and other organic material that accumulates due to the slow decomposition rates and limited soil microorganism activity that occurs in the cold climate. Tannins and other acidic compounds from this layer cause the upper layers of soil to become acidic (Lakehead University 2007). Podzols are formed when precipitation exceeds evaporation, and nutrients, minerals, and organic matter are leached by downward-moving acidic water from the upper soil layers. These soils are unsuitable for agriculture, but can support numerous species of trees, shrubs, and other plants that have adapted to these soil conditions.” http://www.ramp-alberta.org/river/boreal/canada/physical+environment.aspx http://www.ramp-alberta.org/river/boreal/canada/physical+env...

PeterisP 6y ago
The limited activity of soil microbes is caused by cold climates, and as the local climate in that forest warms up, we would expect microbes to decompose all that organic material better, improving the soil. Regarding soil acidity, wood ash is highly basic, so large quantities of ash from a major fire would help reduce the acidity. In essence, with warming climate and mass wood fires we would expect also the soil in these areas to change in ways that are better for agriculture; the only question is about the speed of that change. Also, the whole point of slash-and-burn agriculture in northern europe was that it was infertile and lacking nutrients otherwise - it was not a way of increasing the quantity your fields, you would abandon your fields after a couple of years to overgrow with forest, and slash-and-burn a new one for that temporary influx of nutrients in soil that is otherwise lacking them.

by graeme 6y ago

PeterisP 6y ago

The limited activity of soil microbes is caused by cold climates, and as the local climate in that forest warms up, we would expect microbes to decompose all that organic material better, improving the soil. Regarding soil acidity, wood ash is highly basic, so large quantities of ash from a major fire would help reduce the acidity. In essence, with warming climate and mass wood fires we would expect also the soil in these areas to change in ways that are better for agriculture; the only question is about the speed of that change. Also, the whole point of slash-and-burn agriculture in northern europe was that it was infertile and lacking nutrients otherwise - it was not a way of increasing the quantity your fields, you would abandon your fields after a couple of years to overgrow with forest, and slash-and-burn a new one for that temporary influx of nutrients in soil that is otherwise lacking them.