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CI[)l1:721 - Memorial University of Newfoundland DAI

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45<br />

drier dimatic conditions (Pot2ger and Freizner 1948: 187) or may be due to a<br />

possible pathogen (Sanger at a/. 1977: 462).<br />

By c. 3400 B.P., there was another change in the pr<strong>of</strong>ile. with an increase<br />

in inflUlC rates and percentages fO( hemkx:k and beech (Fagus). Between 3400<br />

B.P. and 200 B.P., beech reaches its maximum values in percentage<br />

composition from pollen pr<strong>of</strong>iles. This has been interpreted as a period <strong>of</strong><br />

closed, mesic. temperate hardwood-hemlock forests (Bradstreet and Davis<br />

1975: 17; Sanger at al. 1977: 462). This change may indicate a period <strong>of</strong> more<br />

abundant moisture (Potzger and Friezner 1948: 187; Matt 1975: 75, Figure 5, 77<br />

Figure 7). The climate may also have been milder than at present (Terrasmae<br />

1973: 208, Figure 9; Bradstreet and Davis 1975: 17).<br />

A further change in vegetational history is evident c. 2000 B.P. This is<br />

manifested in a sharp ina-ease in spruce (Picea), alder (Alnus), and hazel<br />

(CoryIus) with a subsequent decrease in hemlock, beech, and birch (Betura)<br />

(Potzger and Friezner 1948: 189; Bradstreet and Davis 1975: 17; Matt 1975: 79;<br />

Bernabe and Webb 1977: 80, 82), This has been an interpreted as being due<br />

to increased environmental severity <strong>of</strong> an edaphic and/or climatic and/or<br />

anthropogenic nature (Potzger and Friezner 1948: 189; Bradstreet and Davis<br />

1975: 17).<br />

According to Bradstreet and Davis (197S: 17) "the change at 2000 B.P.<br />

begins a record <strong>of</strong> environmental 'deterioration' which becomes increasingly<br />

evident upward in time, despite the fact that relative productivity is apparently<br />

increasing,"

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