HW #4

I took observations from two ecosystems (well two predominantly, they always bleed into each other, sometimes I was in a redwood ecosystem located in a riparian zone for example).
the first ecosystem was an OAK WOODLAND.
The live oak stand, the pine cone, and the douglas fir and california poppy, and scotch broom are all in this ecosystem. this ecosystem was part of/near a river in north berkeley that flows through many parks, including some private land that has wild habitat in it. The oak is well adapted to this climate, so much so that it gives its name to the ecosystem. the douglas fir is another important part of the trees in this ecosystem, with small needles for little transpiration? The scotch broom, an invasive, has somehow found a nitch in almost all the ecosystems of the bay area, and has the evolutionary advantage of being very quick to rebound in disturbed areas, and its quickly grows to a large height, shading out any possible competition. The pinecone perhaps reveals an adaption of fire adaptation, as it will only open when fires come through, and then it releases its seeds into the fertile and sunny new soils that are created by wild fires. I also observed a mule deer in what i would consider to be transition zone of this same oakland ecosystem. Deer have evolved into human made niches (at least with their attitude if not their bio-physical characteristics) a lot and are now common and comfortable in urban periphery zones such as this golf course. They are taking advantage of many of the niches that humans create with regional parks, golf courses, large backyards with landscaping, etc. and seem to be flourishing in the berkeley hills.

The second ecosystem was a RIPARIAN FORREST. In it I found Raspberry (or black berry perhaps), common ivy, california bay trees, white clover (an invasive), nuttalls scrub oak and another plant i believe is a type of lupine? In and around this zone I also found a large stand of coast redwoods, although this was a bit farther down the riparian valley. I also found western swordfern.
The sword fern is adapted to the wet conditions of coastal valleys and riparian zones like this, they often live in and around rocks and areas that are too vertical for other plants to get a foot hold in. They are gimnosperms right?
The nuttall's scrub oak has the adaption of hard and spikey leafs which keep animals from munching on it. This is important because it is always pretty short so it is right at the height of easy munching for deer, etc.
The coast redwood has the adaption of fire resistance and indeed fire symbiosis. When fires happen, the bark of the redwood protects it, and it is helpful in its reproduction. Fires also open up new areas of sun by burning down undergrowth and boosts soil fertility.
The berry bush (whether black or raspberry) has spikes on its stems, protecting it by discouraging any animal from eating these neccesary parts. Its seeds however, are imbedded in sweet fruit which any animal (including us) is more than happy enough to eat and spread around when we move and defecate. Pretty ingenious move there, berry.

הועלה ב-מרץ 3, 2014 12:52 לפנה"צ על ידי