Detritivores

Just learnt this word. It means organisms that use organic waste as a food source. I guess that covers these handsome fungi.

It also covers earthworms.

I dug in my quadrat again and found.... one worm!

I did this worm no favours by digging it up as it was rolled into a ball and knotted into itself which means it was in diapause. Worms go into this sort of sleep state when conditions are unfavourable. The ground is still very dry and they need to be moist to breathe,

I also found a really cute grub and some 'stuff' around a root and some orange stains in the soil. I doubt you can see any of that.

I brought them home to inspect with the lens. The grub inched about. The thing on the root looked fibrous and the orange patch may have been iron that had oxidised. What do I know? I could see a lot of things but not well enough to tell if they were soil mites (they didn't move) or grains.

I was happy as there were some worm holes in the soil.

I also did some more reading on the Field Studies Council Earthworm course. I have to do an assignment about a worm (doh). And thought I may as well use my diapaused worm.

1. What microhabitat is your earthworm in?

Mid-level soil in a woodland.

2. In what ways does your earthworm benefit and/or engineer the ecosystem? Why is this important and what would happen if this job was not being done?

a) It aerates the soil by burrowing and this allows oxygen for aerobic bacteria. Were this not done, the bacteria would not be able to break down organic or mineral matter.

b) Its burrows improve drainage, without which water would just pool on the surface and not seep into the soil.

c) It decompacts the soil by creating burrows. were this not done, roots would struggle to grow into the soil.

d) It redistributes matter through the soil, this moves minerals that plants need into areas accessible to roots.

e) Its ingestion of soil and organic matter both helps to break down waste material (so that it does not form a layer of unavailable nutrients) and increases the fertility of the soil.

3. How might the environmental conditions in the microhabitat change in an unfavourable way for your earthworm? And how do you think your earthworm will respond?

My earthworm was in a state of diapause. It was in a round burrow, rolled and knotted, and very sluggish when I disturbed it. I believe this is because the ground in this wood is a silty clay that is hard and very dry. Despite recent rain, the drought has left all layers below the thin surface very dry. I did the OPAL Soil Survey here six weeks ago and found no worms and no worm holes. I assumed that any worms there might be had burrowed very deep to find moisture and may have been aestivating - slowing their metabolism in the hot and dry conditions, in which worms will struggle as they require moisture in order to breathe through their skin. This time, after some rain, there were some holes and this one worm.

Crone: worm-crazy.

Kerry Calloway marked my assignment - here are her comments:

Excellent. You have selected a microhabitat suitable for earthworms and thought about many different ways your earthworm engineers its environment and the ecosystem benefits this provides. You have also thought about some of the different environmental conditions that create your earthworm's microhabitat and what could happen if they changed. Well done.

Crone: self-congratulatory.