Thursday, December 13, 2007

finish lines

Its 2:46 am. I'm in the library. I have "decided" to pull an all nighter. The gods of study blessed me with an innate ability to pull off not sleeping for large amounts of time and still be functional. I once tried my hand at polyphasic sleeping. It worked pretty well for about five days... which was all I needed. It gets a little lonely, I'll tell you that. I've done nothing but study today, aside from about an hour of hanging out. But it'll all be worth it watching those sunsets from a bar or mountain top (I plan on seeing just as much of one as the other) in Colorado. I don't remember the last time I had a beer. Soon, soon.

But, as I'm studying a little Gen ecology, I thought I'd throw out some of the information I'm learning about. It may be a little difficult without graphs, but I'll give it a go anyway.

Plants can be defined based on their shade tolerance. Different tolerances will have different competitive strategies. Both have their perks and downfalls. Starting with a recently disturbed environment, say, a fire that gets rid of everything in the lanscape, shade intolerant (or ruderals) take over. These plants (called weeds by us insensitive types) are bad at competition for resources. So they have to live in places no other plants want to. They include raspberry, sumac, and mulberries. The James Dean of the plant world, they grow fast, die young.

Shade tolerant species come in underneath them, growing a little slow, but steadier. They compete for resources better, because they often need lower amounts. They also grow a little slower, which means they can wait around for the intolereants to die.

These intolerants are usally dominant longer, unless a lot of disturbance happens in the region.

Tolerant species can use lower amounts of light to photosynthesize, anything over 0 PAR in some cases, while Ps won't occur with some intolerants until 50-100 PAR. That means tolerant species can grow in its own shade (the babies can grow under the parents) restocking the lanscape with the same species. This is called a 'climax' species. The existance of a true climax is disputed. There's a joke in that phrase somewhere.

So,my professor mentioned the top six reasons that biodiversity is on the decrease. In order of importance, here they are.
1. habitat loss
2. habitat change
3. competition from exotic species
4. predation by exotics
5. over harvesting
6. poisoning

That means pollution is smaller than any other risk to the environment. It kind of makes you wonder... with all the pollution you see on a day to basis, how many exotic species do you see and simply not realize it? Find out here.

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