- Identify the organism or biological attribute that you plan to study.
The biological attribute I plan to study is the composition of species influenced by water and topographical features.
- Use your field journal to document observations of your organism or biological attribute along an environmental gradient. Choose at least three locations along the gradient and observe and record any changes in the distribution, abundance, or character of your object of study.
From my field journal I have listed the top five species abundant in each location. My sampling locations each had a 3m radius.
Location 1: (River’s edge)
- Lanky Moss (prevalent)
- Salmon Berry (prevalent)
- Vine Maple (most prevalent)
- Trailing Raspberry (dominant)
- Dense Sword fern (dominant)
Location 2 (middle topography approx. 15m from river’s edge):
- Salal (increasing prevalence)
- Trailing Raspberry (present)
- Vine Maple (present)
- Dull Oregon Grape (Increasing prevalence)
- Flat moss (moderately prevalent)
Location 3(highest topography approx. 30m from river’s edge):
- Salal (most prevalent)
- Dull Oregon grape (dominant)
- Red huckleberry (scattered)
- Shallon (prevalent)
- Bracken Fern (moderately prevalent)
- Think about underlying processes that may cause any patterns that you have observed. Postulate one hypothesis and make one formal prediction based on that hypothesis. Your hypothesis may include the environmental gradient; however, if you come up with a hypothesis that you want to pursue within one part of the gradient or one site, that is acceptable as well.
My hypothesis is the presence of water and varying topographical features influence specific species growth. From my observations I noticed that the abundance of species found near the flowing river varied from the ones in the other locations I sampled. You can also notice that there is increasing prevalence of species from the middle topography and the highest topography. The prediction I have made based off my hypothesis is that species with high precent coverage near water will not be present at the same abundance at a steeper topography without the presents of water.
- Based on your hypothesis and prediction, list one potential response variable and one potential explanatory variable and whether they would be categorical or continuous. Use the experimental design tutorial to help you with this.
Based on my prediction and hypothesis a potential response variable would be the abundance of species (percent coverage) found at each sampling location. The corresponding potential explanatory variable would be soil moisture content. This would be considered a continuous measure as both variables are continuous.
water and differing topological features (aspect etc) seem like pretty good drivers or predictors
these is likely related to soil productivity, and although you won’t be digging soil pits, you may find some information in literature for Discussion to explain why you are seeing differences
Your hypothesis and prediction look good. Your predictor variable could be distance from the river / elevation or a combination of both. I’ve had students take soil samples before though sounds like you have already done your sampling.