Wednesday 18 November 2009
what is an ecosystem?
it consists of interdependent communities of plants, animals, microscopic organisms & physical environment. all these different elements interact & form a complex whole, with properties that are unique to that particular combination of living & non living elements
energy flow & material cycles
ecosystem boundaries are generally delineated by climate: desert ecosystems in the subtropics, tropical rainforest ecosystems near the equator & tundra ecosystems near the poles
distribution of biomes (biome is used to describe a major vegetation type such as tropical rain forest, grassland, tundra etc, extending over a large geographic area)
as climates have changed in the geologic past, ecosystems have shifted in response but past climate changes were slower than the projected future changes
climate patters affect biome distributions
aquatic ecosystems
why we need wetlands?
wetlands provide an important service to our surroundings. storm waters flowing into a wetland lose energy & spread out across a broad area, thus reducing flooding downstream. furthermore, sediment & contaminants, such as iron & acidity from mine runoff & nitrogen from farm fertilizers, are removed as water percolates through wetlands before entering our drinking & irrigation water
wetlands are also biologically diverse ecosystems, providing home for endangered species and a refuge for migrating birds. this make them ideal places for hiking, bird watching, canoeing & fishing
worth saving
ecosystems are valuable to humanity because they assist us with:
provisions: food (seeds, fruits, game, spices); fiber (wood, textiles); medical & cosmetic products (dyes, scents)
environmental regulations: climate & water regulations; water & air purification, carbon sequestration; protection from natural disasters, disease & pests
cultural benefits: appreciation of, & communion with, the natural world; recreational activities
game on..
lets fish..
should i grow up, hope to see you..
credits: dire predictions, understanding global warming (the illustrated guide to the findings of ipcc: intergovernmental panel on climate change - michael e mann & lee r kump)/ flickr/ globalchange.umich.edu/ numerous data
