Humus - is the Sky really the Limit of your Compost Pile in the Kitchengarden 🥦 Kesser and Steen

Описание: What is Humus all about and is the Sky really the Limit of your Compost Pile in the Kitchengarden ? Soil health depends on humus, the organic matter driving biological processes and stabilizing structure and texture. Woodlice assist by decomposing plants. While reduced tillage boosts yields and carbon storage, humus levels above 8% may cause nutrient leaching. This podcast talks about Kesser and Steen, from the Nature and Innovation class, that have heard and read a lot about how humus (dead organic matter / compost) in the soil is good for the vegetable garden.

Humus?
Let's just repeat what 'humus' in the soil is. When you take samples and test the structure and texture of the soil in the laboratory, you are not reading the chemical values ​​(N-P-K) that you often hear about and can read on bags of fertilizer.
Organic matter in the soil Collective term for living and dead organisms in the soil. It is carbon (C), which is chemically combined with hydrogen (H) and oxygen (O) and / or other elements (e.g. nitrogen (N), phosphorus (P) and sulfur (S).

The organic matter of the soil is a reservoir of energy - energy that drives biological processes.

Microorganisms play an important role in the transformation of organic matter and nutrients. It is 80-90% of the total metabolism in the soil that comes from microbial processes).

The biological functions of the soil also influence the chemical and physical properties by providing stability to the physical soil functions, e.g. cementing with root exudates.

When buying new plants to plant a new garden, many people will test the pH value of the soil to make sure that the acidity conditions are "correct". We talked about this a short time ago.

Humus calculation - CO2 binding in the soil
The plow layer (30 cm) contains approx. 4200 t of soil per ha. On average, this soil contains approx. 2.5% humus.
Humus contains 58% carbon (C). This means that the plow layer contains (4200 t x 0.025 x 0.58) = approx. 61 t of carbon per ha.
This corresponds to approx. 224 tons of CO2 equivalents per ha.

With an optimal supply of nutrients - including nitrogen (N) - it is considered realistic to increase the humus content by 0.8% per year, corresponding to 0.02% points. This means that an additional 224 t x 0.008 = 1.8 t of CO2 per ha. per year can be bound.
On 2.5 million ha of cultivated agricultural area, an additional approx. 4.5 million t CO2 per year - or
around 30 million t CO2 by 2020.

Humus calculation - CO2 binding in the soil
The plow layer (30 cm) contains approx. 4200 t of soil per ha. On average, this soil contains
approx. 2.5% humus. Humus contains 58% carbon (C). This means that the plow layer contains
(4200 t x 0.025 x 0.58) = approx. 61 t of carbon per ha. This corresponds to approx. 224 tons of CO2 equivalents per ha.
With an optimal supply of nutrients - including nitrogen (N) - it is considered
realistic to increase the humus content by 0.8% per year, corresponding to 0.02% points.
This means that an additional 224 t x 0.008 = 1.8 t of CO2 per ha. per year can be bound.
On 2.5 million ha of cultivated agricultural area, an additional approx. 4.5 million t CO2 per year - or around 30 million t CO2 by 2020.

Rule of thumb: An increase in soil humus content of 1 percentage point corresponds to a binding of approximately 89 tons of CO2 per hectare (calculated as (4,200 x 0.01 x 0.58 x 3.67)).

#organickitchengarden #soilhealth #kesserogsteenpåtur

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