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Four things scientists know about how soil affects fertility

By improving organic carbon in the soil, nutrient absorption can be improved and waste can be reduced.

To understand soil biology and physics, Rothamsted Research scientists use X-ray computed tomography to examine aggregates at microscopic levels below 100 microns (one millionth of a meter). I’ve been doing it.

Such close observation is required because carbon is isolated in pores of this size and the water retention capacity of the soil can be confirmed at this level, explains Andrew Neal of Rothamsted’s Sustainable Agriculture Science Department. ..

reference: How to achieve healthy grassland soil

At a recent meeting of the Corn Growers Association, he mentioned what they had learned so far.

1. Soil structure is very important for soil fertility and efficiency

There is a strong relationship between the total amount of organic carbon (OC) in the soil and the connected porosity (the extent to which the pores are connected and have the ability to retain water).

Deteriorated soils without plants for more than 50 years had very low OC and little connected porosity. These soils were then converted to arable land and grassland, benefiting from carbon gains and porous connections for over a decade. However, permanent grasslands stored the most carbon and had the highest porosity.

You can only produce so many connected porosities, and all soils have their limits.

Soil texture is very important – clay soils work very well and sandy soils are not very effective – but managing carbon in the soil can improve the performance of the system. ..

2. Improved connectivity improves hydraulic conductivity

Permeability is the ability of the soil system to transfer nutrients for plants and oxygen for microbial processes.

Improving the connected porosity improves the hydraulic conductivity. That is, nutrients and water move very effectively through the soil.

Connected porous and low hydraulic conductivity soils exhibit very high anoxic levels (oxygen deficiency) even in dry conditions.

“Highly connected interstitial spaces not only store water for elasticity, but also control the amount of oxygen that controls the activity of microorganisms, all of which can be traced back to the amount of organic carbon in the soil. You can, “says Professor Neil.

3. Genes drive important processes

The sequence revolution that has taken place over the last two decades has given scientists a better understanding of soil microbiology.

Soil structure is influenced by genes and organisms present in the soil.

“Supplying that soil carbon stores water, stores nutrients, effectively migrates them, and produces a very breathable, good and open structure with a lot of carbon. Without it, the connections are very poor, they don’t retain much water, they don’t store a lot of carbon, and the organism becomes a soil that has to return to anaerobic processes, which is detrimental to efficiency and climate change.

“We can see how the abundant genes that drive important processes, especially for agricultural production, evolve in response to these physical changes brought about by carbon management,” added Professor Neil. I will.

One example is catabolic nitrogen metabolism as the microbial process switches from oxygen use to nitrogen, which promotes the release of nitrous oxide from the soil into the atmosphere. This means that it does not reach the crop and causes a warming effect. The number of genes present in the systems that drive this process is much lower in systems that are poorly connected than in grasslands and can be cultivated in bare fallow land.

4. Not all N’s are bad

Broadbalk – one of the oldest ongoing experiments in the world to test the effectiveness of inorganic and organic fertilizers – shows that using farm fertilizers as a carbon source changes the way nitrogen is distributed in soil.

Nitrous oxide emissions are less, rather than losing more nitrogen, and increase nitrogen accumulation in farm fertilizer-spread soils.

Four things scientists know about how soil affects fertility

https:///livestock/grassland-management/4-things-scientists-know-about-how-soil-affects-fertility Four things scientists know about how soil affects fertility

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