Wednesday, January 25, 2023

Woodland Pond

I'm always fascinated by the color of natural woodland ponds I come across in winter landscapes. There's always a murkiness, a lack of clarity, that piques my interest.

I've tried to find out "why" and I'm not 100% sure I've hit on the correct explanation, since most seem unverified and colloquial. The most plausible version seems to be that it's due to the ability of hardy algae to photosynthesize in weak, barely-there winter sunlight, unlike bacteria and plants that have a dormancy phase. Proliferating algae continue to give off oxygen that is important for other pond critters to breathe, so are a vital component to the life of a pond, of its 'metabolism' - it's not a bad thing. In other seasons of the year, their numbers are kept at bay by other competitors for the same resources.

https://www.pondworksonline.com/blog/2016/2/17/winter-algae-in-your-pond

6 comments:

Lucy Schultz said...

The color isn't just murkiness from the silt and sediment of the leaf litter and habitat?

Wendy said...

If this is an area where water usually collects it most likely is a vernal pool. Vernal pools of significance are protected as well as the area around them.

Debbie said...

I automatically thought the same as you, but I kept wondering about it since those ponds are clear and sparkling in summer. Aquaria sites consistently mention winter 'murkiness' of outdoor, managed ponds

Debbie said...

Yes, vernal pools are a special case since they are seasonal only and important breeding areas for key indicator species.

This particular pool is a year-round feature

Wendy said...

Yes, temporary....like ruts from skidders...are a bad thing, but loggers will say, we are creating vernal pools and habitat for homeless creatures. Unfortunately, I don't think our state foresters share the same sentiment!

Debbie said...

Lucy, your comment has me thinking further ...

Perhaps it's the particular light refraction characteristics of snow and ice that show us the presence of algae, something we don't usually see when it's liquid water. I've noticed that when there's melting ice or just-forming ice/slush in the shallow parts of the lake, those areas have a greenish, milky looking tinge to them.