This Great Basin range much of northern America (Mohammed & Tarboton 2012). Using the palynological findings obtained from the Lake, from a single peat core, this report will provide an interpretation of the past vegetation and the climate around the Great Salt Lake. This core contains samples of pollen grains dated from 200, 000 years ago in the lakes prehistoric beginnings (Rawley 1980) to the present. The palynology specifies the nature of climate around the time when they were deposited in the core.
The given types of pollen only grow in certain climatic conditions. The flora around the Great Salt Lake contain of plants that can grow in high levels of salinity and soil alkalinity (Flowers 1934). For example, Asparagus and Cyprus grow in these places (Allen & Falkenborg 1996). For the past 300, 000 years the climate has undergone a series of glacial-interglacial transitions. This means that the climate has gone through many cool and warm periods (Kowalewska and Cohen 1997). Palynology and isotopic analysis helps us to reconstruct climatic transitions (Pielou 2008).
The topography of the lakes surrounding mountains and fossil remains in the lake of trees can provide us with evidence to study the glacial conditions of the quaternary period around the Great Salt Lake (Flowers and Evans 1966). The climate condition around the Lake is ‘sub-humid’, in the modern era. The average temperatures during the last years of the last millennium ranges from 25.3?C to -2.2?C (See table 1), around the Great Salt Lake. The warm temperatures of around 25? shows us that we are, in fact currently in an interglacial period. The last glacial period, The Wisconsin glaciation, in America ended around 10, 000 years ago (Hunt, Varnes & Thomas 1953).
A set of 8 samples containing palynological data has been given to study in this report. To analyse the data for this report, the samples were taken from a single core drilled into the Great Salt Lake in Utah, North-western America (Flowers 1934). A table was made in an Excel spread sheet (see table 2), identifying the different pollen types, with the help of the key that was provided to identify the types of pollen that are in the samples. After the pollen grains on each of the eight slides were counted and identified, the data was converted into percentages (see table 3) and then these percentages were transformed into graph (see figure 2). The data that are in the form of percentages are the data that will be referred to throughout the report in the sections of results, discussion and conclusion. The palynological evidence from the Great Salt Lake are from plants that can only survive in certain climatic conditions. For example, Erigonum pollen grains are from plants that support cold climates (Minckley et al. 2008). Amaranthus on the other hand is a pollen type from plants that are primarily existing in warm climatic conditions.
The vegetation that is shown by the 8 samples of pollen from the core, illustrate what the climate was like in the area surrounding the Great Salt Lake from the modern era to when the first sample was dated to, all the way back to 220, 000 years ago. The last sample (sample 8), is a type of pollen that is particularly abundant over the others. Therefore it suggests that the environmental conditions were more favourable to this type of pollen plant growth. The raw data count of the pollen samples presented in Table 2, will not be interpreted in this report. The percentage data depicted in Table 3, of each type of pollen that was calculated, will be interpreted, instead. Ambrosia, Sarcobatus and Quercus has the highest percentages of pollen grain types in Sample 1 (see table 3).
These pollen types favour warm conditions thus allowing to make the assumption that the climate in this period was warm. Poacea and Pinus has the highest percentages of pollen grain types in sample 2 (see table 3). These pollen types favour moderate transitional climates. A major amount of pollen grains in sample 2 prefer cold conditions (Erigonum and Picea) and a minor amount of grains in sample 2 prefer warm conditions. The data indicates that the climate at the time the stratigraphic layer was formed, was moderate to cold.
There has been a sharp decrease in Ambrosia, Sarcobatus and Quercus from sample 1 to sample 2, while Pinus and Poaceae has had a significant increase (see figure 2). Picea, Erigonum and Artemisia of the sample 3 data mostly contains pollen grains that prefer colder types of atmospheric conditions, but the highest percentage of sample 3 is Picea. In sample 3 you can see that there has been a significant increase of Picea while Pinus has had a sharp decline in percentage (see figure 2). According to Table 3, you can see an increase of the total pollen percentage from sample 3 to sample 4.
Amaranthus and Quercus has the highest percentage of the pollen grains types in the sample 4 (see table 3). This suggests that the climate was warm as these types of pollen prefer warmer climates. Sample 5 continues this momentous rise in the pollen grains. Ambrosia, Quercus and Artemisia has the highest percentage of grains in sample 5 (see table 3). These types of pollen prefer warmer climates, this suggests that the 5th sample was formed in a time of warm climate. A significant decline of the total percentage from sample 5 to sample 6 is visible. Sample 6 and sample 2 has similar percentages of pollen grain (see figure 2), which indicates a moderate to cold temperature climate. There is a significant increase of the total percentage from sample 6 to sample 7. Sample 7 percentages imitates that.
