Draft papers due with – reviewer comments, outline,
wordsearch
Watershed - The area of
land where all of the water that is under it or drains off of it goes into the
same place. (The land that contributes water to a given site.)
Evaluate the quality of
a watershed – how good is it at doing its job?
What should we look for
when we evaluate a watershed?
Drew two watersheds –
Watershed 1 - Poor quality - with factory, livestock in stream,
houses by stream, crops
Watershed 2 - Good quality – no factory, livestock in pens away
from water, houses away from water, crops follow contours
Industry 1
factory that discharges into river 0
factories
Agriculture livestock in water, crops livestock in pens, crops in
contours
Human population high along the river trees between river and houses
Natural landscape deforestation many trees
Conclusion – watershed 1 is poor quality
Industry factory water treated before
discharge into river
Agriculture put livestock in pens and crops
in contours, don’t use pesticides
Human population plants trees between river and houses
Natural landscape plant more tress
What do forests have
to do with this?
See Table 3.2
Forests occupy 30% of the earth’s land surface
Forest 29% (tropical
15%, temperate 7%, boreal 7%)
Savanna 14%
Grasslands 10%
Tundra 7%
Deserts and Scrublands 21%
Cultivated lands, wetlands, etc. 19%
Ecosystem services –
things that the ecosystem does for us
Aesthetics – ecotours, spiritual etc.
clean the air
store carbon and make it available (to primary producers)
protect watersheds and water
Others
absorb and reflect solar
energy
roots penetrate soil and
increase filtration (rather than runoff)
No comments:
Post a Comment