[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: Aquatic Plants Digest V6 #40 How deep will plants grow

In a message dated 2/2/03 5:55:27 AM Eastern Standard Time, 
Aquatic-Plants-Owner at actwin_com writes:

> Date: Sat, 01 Feb 2003 21:09:31 -0500
>  From: Thomas Barr <tcbiii at earthlink_net>
>  Subject: Re:how deep will a plant grow?
>  > Tom's Teaser: What is the maximum depth in lakes for
>  > plants(Dicots/monocots only,
>  > "The depth maxima for the vascular plants plateau at around
>  > 5.5 to 6 m regardless of water transparency. This suggests
>  > that factors other than available light limited the depth
>  > maxima for vascular plants and a case for hydrostatic
>  > pressure effects is strongly suggested. "

I have to strongly disagree, while pressure at extreme depths might change 
the biochemistry of living creatures the point at which this occurs is far 
beyond the penetration of light. Water pressure doesn't have anything to do 
with plant growth under water since the inside pressure of a water filled 
plant is the same as the outside. I would expect find moss at a more extreme 
depth due to the capacity of moss to grow in low light levels. Also 
freshwater usually isn't very transparent due to organic loads in the water. 
(yes I know there are very clear freshwaters but they are usually found in 
very cold places with very little life) I'm betting that live vascular plants 
have been found in water as deep as 100 feet or more depending on the clarity 
of the water. I scuba dive and I have never seen any cut off of plants due to 
anything but light levels.