Colin_Bio482-02
soiltest
a) Silty clay soil
b) This soil texture can store a large amount of water (which I tested, to be discussed later) due to the electronegativity of the clay particles present, this would also increase the soils ability to absorb nutrients from inputs. Furthermore, having the silty quality means while the deep soil is good for a tap root, the top layer also has more nutrients than a sandy layer would--these qualities combined make this soil type ideal for both larger perrenials (with large taproot systems), and grasses and annual herbs (with fibrous root systems), all of which seem to be present and persistent at this site. The presence of persistent plants in turn helps slow water erosion of the top soil, preserving it.
c) Vegetation variable: Perennial woody shrubs, annual herbs, annual grasses. In the soil annelids were noted, as well as Armadillium.
d) The effects of the vegetation on soil quality were discussed in section b. However, both of the animals found in the soil are decomposers, who would be turning dead organic matter into nitrogen containing compounds. This is good for two reasons: 1) It increases the soils nitrogen content. 2) It removes dead organic material from the system, which if left in the soil could cause it to become water-logged and hypoxic.
e) Erosion is not likely in the main body of my site. However, it would receive and trap soil being washed down the slopes surrounding it (possibly giving the clay soil its silty texture?), there would be some erosion at the NE portion of my site, where the plain begins to slope down towards the reservoir, however the effect would be muted by all the persistent plants.
f) I believe many of my answers above demonstrate the importance of the soil texture, from the texture a prediction could be made about which organisms would be found there, then looking at the realized organisms found there and their interactions (biotic, and abiotic) it can help in turn explain the soil texture--all together giving a more complex understanding of the system.
g) Because I'm a dork I took five soil cores from five random locations on my site, I recorded the average of their (Weight_wet) - (Weight_dry) after leaving the wet samples in a 150 degree Fahrenheit oven for 8 hours, and found the average water density (mg/cm^3) to be 127.4 mg/cm^3. This test was performed on soil samples taken from the site five days since it had last rained, which suggests as the texture test above did that this soil has a high capacity to retain water. An interesting follow up experiment would be to do this one again, however collect the first soil sample on the last day of a rain storm, then collect samples from the site every day for a week or two, and plot the decreasing water density of the soil--to measure drainage, and ultimate retention.
soiltest
a) Silty clay soil
b) This soil texture can store a large amount of water (which I tested, to be discussed later) due to the electronegativity of the clay particles present, this would also increase the soils ability to absorb nutrients from inputs. Furthermore, having the silty quality means while the deep soil is good for a tap root, the top layer also has more nutrients than a sandy layer would--these qualities combined make this soil type ideal for both larger perrenials (with large taproot systems), and grasses and annual herbs (with fibrous root systems), all of which seem to be present and persistent at this site. The presence of persistent plants in turn helps slow water erosion of the top soil, preserving it.
c) Vegetation variable: Perennial woody shrubs, annual herbs, annual grasses. In the soil annelids were noted, as well as Armadillium.
d) The effects of the vegetation on soil quality were discussed in section b. However, both of the animals found in the soil are decomposers, who would be turning dead organic matter into nitrogen containing compounds. This is good for two reasons: 1) It increases the soils nitrogen content. 2) It removes dead organic material from the system, which if left in the soil could cause it to become water-logged and hypoxic.
e) Erosion is not likely in the main body of my site. However, it would receive and trap soil being washed down the slopes surrounding it (possibly giving the clay soil its silty texture?), there would be some erosion at the NE portion of my site, where the plain begins to slope down towards the reservoir, however the effect would be muted by all the persistent plants.
f) I believe many of my answers above demonstrate the importance of the soil texture, from the texture a prediction could be made about which organisms would be found there, then looking at the realized organisms found there and their interactions (biotic, and abiotic) it can help in turn explain the soil texture--all together giving a more complex understanding of the system.
g) Because I'm a dork I took five soil cores from five random locations on my site, I recorded the average of their (Weight_wet) - (Weight_dry) after leaving the wet samples in a 150 degree Fahrenheit oven for 8 hours, and found the average water density (mg/cm^3) to be 127.4 mg/cm^3. This test was performed on soil samples taken from the site five days since it had last rained, which suggests as the texture test above did that this soil has a high capacity to retain water. An interesting follow up experiment would be to do this one again, however collect the first soil sample on the last day of a rain storm, then collect samples from the site every day for a week or two, and plot the decreasing water density of the soil--to measure drainage, and ultimate retention.