Temperature And Betula Disribution On The Holy

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Temperature And Betula Disribution On The Holy Range, Massachusetts Essay, Research Paper Temperature and Betula distribution on the Holyoke Range, Massachusetts Abstract In this study, it will be tested whether temperature affects tree densities in the genus Betula on different slopes of the Holyoke Range, specifically the north and south faces of the mountain range. My prediction is that the north face of the mountain will have a higher density of these trees than the south face of the range because of the temperature differences of the north slope being warmer than south slope for the range of growth for these trees. This experiment can be used to predict patterns of vegetation in other similar latitudes and slopes around the world. On September 20, 2000, the birch tree

genus, Betula, density was measured on the north face of the Holyoke Range and on September 27, 2000, Betula??s density was also measured, but on the south face of the Holyoke Range. There were eight sites laid across a 150m transect line running across the slope starting from a subjectively chosen point. Based on the data collected on the Holyoke Range, the birch trees densities were not significantly higher on the north face than on the south face of the mountain range. Eight separate t-tests were performed, four on the density of the adult birch trees, and another four on the basal density of adult birch trees. From this data analysis it was possible to determine that the results were due to chance, not congruent with my prediction. From the results of my data, it can be

concluded that temperature is not a factor in the tree density of Betula. In fact, temperature is not the only factor that can determine the growth of Betula, or other species of trees. Certain biotic and abiotic factors that can explain vegetation patterns of similar areas compared to this study. Introduction In this study, it will be tested whether temperature is one of the factors that affect tree densities in the genus Betula on different slopes of the Holyoke Range, specifically the north and south faces of the mountain range. In mid-latitudes in the Northern Hemisphere, northern-facing slopes are cooler than south-facing slopes because they receive less direct solar radiation. R. B. Livingston found that slope variation on the range exerts marked influence on all

environmental factors (Livingston 1982). The upper, north-facing slopes are steep and abrupt (35?a to 40?a), while the south-facing slopes are more moderate (20?a). Accordingly, the angle of mid-day insolation is typically 55?a to 60?a greater on the south slopes than on the north slopes, except in late fall and winter when no direct light strikes the steep north-facing hill (Livingston 1982). Even though the area this experiment took place in does not exactly exhibit the same temperature variations discussed by Livingston, this can be still be used as a representation of north-facing slopes being warmer than south-facing slopes around the world. On the Holyoke Range there are various species of Betula that have similar areas of optimal growth. The cherry birch, Betula lenta, can

be found both in woods and in open and uplands on moist, protected, north-or east-facing slopes (Elias 1980). The yellow birch, Betula lutea, can also be found among cherry birch, but in the southern portion of its range, it can grow in cooler marshlands. The paper birch, Betula papyrifera, is found at lower elevations and often on north and east-facing slopes. Also the paper birch is one of the first species to occupy areas devastated by fire. Another species with similar traits to the paper birch is the gray birch, Betula populifolia, which occupies wide areas of abandoned fields and burned-over lands (Elias, 1980). These characteristics of these four Betula species are important because sometimes these trees are not in their optimal growth area, so implying that other factors