Question about how Trees rot

[l008com]

This is an odd, and oddly specific question. But consider this scenario:
A live tree blows over in a storm. Lets assume enough of the roots are damaged that the tree dies. Most of the tree is on the ground but some of its branches are dangling in the water. Like a stream or pond nearby. Are those branches that are in the water, going to rot faster and break off? Or is being actually IN the water, going to slowdown/stop rotting? Or will they tend to rot faster right above the water line?

I see this a lot in the woods where I bike and I'm wondering how these trees get reabsorbed, long-term.

 

[roadrunner]

They rot faster when they make contact with the soil. In the water fungi can't grow on them if they are completely submerged, totally slows down degradation. However, I would imagine if they are only periodically submerged that would help them decay faster during the periods it's out of the water.

They also don't rot as quickly if they don't contact the soil.

Soil contact is critical for woody things to decay, because it traps moisture, which provides the various decomposing microorganisms complete habitat, along with a food source.

It's actually one of the benefits of livestock in a field (assuming the livestock are moved and allow the field to recover), because they stomp/compact all the biomass closer to the ground where the microorganisms are located.

Look at leaves on the forest floor, the ones on the very top are not decomposing, they won't until next year's fall when they are covered and the leaves underneath have turned into moist duff that make contact with the dry leaves that were once the very top of the mulch covering.

 

[Chuck]

They rot faster when they make contact with the soil. In the water fungi can't grow on them if they are completely submerged, totally slows down degradation. However, I would imagine if they are only periodically submerged that would help them decay faster during the periods it's out of the water.

They also don't rot as quickly if they don't contact the soil.

Soil contact is critical for woody things to decay, because it traps moisture, which provides the various decomposing microorganisms complete habitat, along with a food source.

It's actually one of the benefits of livestock in a field (assuming the livestock are moved and allow the field to recover), because they stomp/compact all the biomass closer to the ground where the microorganisms are located.

Look at leaves on the forest floor, the ones on the very top are not decomposing, they won't until next year's fall when they are covered and the leaves underneath have turned into moist duff that make contact with the dry leaves that were once the very top of the mulch covering.

It takes oxygen to decompose heavy carbon such as tree limbs. That's why trees are still standing in manmade lakes a hundred years old. Soil microbes are what makes things decompose and without adequate oxygen they die. It's why so many gardeners have sickly plants, they reduce the oxygen by too much water for too long. The same thing applies to compacted lawns. The soil is so compacted that oxygen cannot reach the root systems of grass. The microbes are deprived of enough oxygen that they no longer can function normally, thus sickly yellow patchy grass.

 

[DirtMechanic]

In a word, sugar.

This tree in my yard, well across my line in my neighbors yard was felled about 10+ years ago roughly. Ramial wood goes first. The white mold phase. Move to other fungi. Everybody gets in the chow line, each appreciating the food given by the previous others. The great white decomposers of the world. The degradation of lignin which holds a special place in life and the cycles that support it, unlike a pine.

But I digress.

Ultimately it's left carbon and oxygen and as you know those are elements. It's that you may not appreciate how damned tough it is to break down an element, or more specifically break elements apart to give their energy back ala Einstein light. These in the breakdown stage are molecular bonds breaking down, not the elements nor the atoms of which they consist That would come much later. The terra preta soils of the Amazon educate me on the long term effects of carbon in soil over thousands of years.

CO2 goes back to whence it came. Slowly, the sugars and foodstuffs get eaten first.

Water adds hydrogen and oxygen to the process. Oxygen, Carbon and Hydrogen meet in the river and carry on as well, to your question. It's basically a form of the processes of oxidation of the components of sugar C12-H22-O11.

Carbon (C), Hydrogen (H), Oxygen (O): Sourced from air and water; they make up the bulk of plant dry weight.
Sugars.



Nitrogen (N): Drives green leaf growth and stems.
Phosphorus (P): Builds strong roots, flowers, and fruits.
Potassium (K): Regulates water and boosts disease resistance.
NPK see fertilizers.


Calcium (Ca): Forms strong cell walls. Magnesium (Mg): Acts as the core molecule in chlorophyll.
Sulfur (S): Aids in making proteins and vitamins.

Minor Nutrients:
Iron (Fe): Helps form chlorophyll.
Manganese (Mn): Assists photosynthesis and enzyme activation.
Boron (B): Builds cell walls and helps with reproduction.
Zinc (Zn): Controls growth hormones.
Copper (Cu): Aids photosynthesis and flavor.
Molybdenum (Mo): Converts nitrates for plant use.
Chlorine (Cl): Regulates osmosis and plant health.
Nickel (Ni): Supports seed germination and nitrogen metabolism.


The degradation this thread is about starts at the top. And eventually we call it compost and put the materials back out as they contain the residual elements and macro and micro nutrients from the parent plant.