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(Due Monday, December 8)
The object of this exercise is to have you practice making some observations of a natural ecosystem and draw some conclusions regarding causal relationships between different elements in the ecosystem. Observation (data gathering) and analysis (evaluation of the data) are two major tools that scientists use to learn about natural processes and the relationships between different components of a natural system.
What you need to do:
1. Pick a site to observe. Your site should be as little impacted by human activities as possible so that you can observe native plants and animals (insects, birds, small mammals, etc.) in their natural habitat. Choose also an area where you can observe geomorphic processes, such as a stream channel, or hill slope, or ocean beach, or sand dunes. An example of a site close by is the riparian zone (streamside zone) along Copeland Creek on the north side of campus. The area of your site should be small enough to describe in some detail, yet large enough to include a variety of plants, animals, and natural processes.
2. What is the climate like? Before you visit your site, write down what you think the local climate is like. You can get this type of information from the TV weather reports, newspaper weather maps, or even more precisely, from maps of temperature and precipitation in the Atlas of California, or climate data from a nearby weather station. Or try the Climate of Sonoma County web page (this is old data, hard to read): http://libweb.sonoma.edu/regional/climate/
Don't spend a lot of time searching this out unless it really interests you. You should, however, have a general idea of what climatic influences there are on your site. For example, if you choose a coastal site, it will probably have a lot of fog in summer and more precipitation in winter.
3. Observe your site. I recommend that you plan to sit quietly at your site, alone, for at minimum half an hour, even before you begin to take notes. Use ALL of your senses when you observe, and be as detailed as possible. Take a notebook and pencil, and visit your site for an hour or so, writing down everything you see, hear, smell, touch. Observe the lay of the land (topography), including the general slope (flat, gently rolling, steep slopes, etc.). Are you sitting on a hillslope? Or next to a stream channel? Draw some sketches of your site and what you see. If so, why is it there? What sorts of erosional and depositional processes can you see evidence of? Try to identify the numbers and types (species if possible) of trees at your site. How tall are they? How close together? Is the ground mostly shaded or mostly open? What types of underbrush do you see? Are there shrubs, or only grasses, or bare ground, or leaf litter? If there is bare ground, is the soil heavy and clayey or sandy, or gravelly? What evidence do you see of animals living at your site (e.g. dirt mounds from moles, footprints of birds, actual observations of individuals).
4. Draw some conclusions from your observations. What is the role of climate at your site? For example, does the type and density of vegetation reflect the amount of sunshine, rainfall, fog, etc. that this location receives? What about soil forming processes? Where do you think the parent material of the soil came from? Was it bedrock, or has it been deposited by landslides, or by river flooding, or by wind blowing sand and dust?
5. What to turn in. Please turn in a neat, handwritten or typed version of your field notes, what you observed, and your ideas about the relationships between the different aspects of your site. How does each element in your ecosystem affect the others? What do you think this place would look like at different times of the year (e.g. does the creek dry up in summer, do the trees lose their leaves in winter?) Can you make some general statements regarding each of the natural spheres at your site: the influence of the atmosphere, hydrosphere, biosphere, lithosphere, and how they fit together? PLEASE NOTE: This exercise MUST be done live, not from memory of a place, even if you know that place very well. You will lose major points for not doing this properly, and you will lose out on a great learning experience.
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