Jesse L. Morris, Andrea R. Brunelle and A. Steven Munson
Western North American Naturalist, 70(2):175-188. 2010
- What Journal was this article published in? (2) Ans. The article was published in BioOne. It is a nonprofit, online website of core research in the biological, ecological, and environmental sciences. It provides a sustainable online platform for over 170 journals and books published by nonprofit societies, associations, museums, institutions, and presses.
- What are three of the human-caused disturbances that can alter the ecology and appearance of the landscape? (3)
Ans. Human caused disturbances that can alter the ecology and appearance of the landscape is:
1. Logging
2. Mining
3. Livestock Grazing and agriculture
- What three research questions that are investigated in this paper? (3)
Ans. The three research questions investigated in this paper are:
(1) How are the signals of historically documented disturbances recorded in the sediments?
(2) What type of unique sediment logical signature do historical disturbances exhibit?
(3) How does the frequency and interaction of disturbance events compare before and after settlement?
- What was the main method used to determine the vegetation? (2)
Ans. The main method used to determine vegetation was Palynological methodology. It used fossil pollen and charcoal from lake sediments to assess effects of land-use change, wildfire, and spruce beetles on vegetative structure.
- What was the main method used to determine if fire was present? (2)
Ans. The main method used to determine the presence of fire was through Charcoal analysis. Charcoal samples were taken at every 1 cm of the core. Each sample was analyzedby methods presented in Whitlock and Millspaugh (1996). Magnetic Susceptibilty was performed at 1-cm intervals using a Bartington ring sensor equipped with a 75-mm aperture.
- What is the main vegetation type at this research site? (2)
The main vegetation type at this research site was Subalpine vegetation. The MCA portion of the record suggests that, consistent with warmer conditions in western North America, vegetative conditions were dominated by Poaceae and Pinus. The LIA portion of the Blue Lake record represents a landscape dominated by forbs, tall grasses, and the arboreal species Picea and Abies in response to cooler conditions.
- Did grazing have a positive or negative impact? (2)
ANS. Grazing by sheep and cattle adversely affected the ecology of the Wasatch Plateau (Hall 2001). The Blue Lake pollen record captures the arrival of livestock and subsequent heavy grazing with a significant decline in preferred forage vegetation (e.g., Poaceae) and a concurrent Artemisia
- What was the conclusion of this research? (4)
The MCA portion of the record suggests that, consistent with warmer conditions in western North America, vegetative conditions were dominated by Poaceae and Pinus. The LIA portion of the Blue Lake record represents a landscape dominated by forbs, tall grasses, and the arboreal species Picea and Abies in response to cooler conditions. The Blue Lake record indicates that fire played a role in modifying the Wasatch Plateau during the LIA. However, fire does not have any detectable role in shaping the modern ecology on the Wasatch Plateau. The spruce beetle epidemic during the 1980s has contributed more to current vegetative structure than any other natural disturbance event in the 750-year Blue Lake record. A longer temporal record is required to determine whether spruce beetle events have occurred before the 750-year Blue Lake record. As a result of this study, it does not appear that any other severe spruce beetle epidemics have occurred over the past 750 years at Blue Lake prior to the most recent epidemic initiated in the mid- 1980s.
