Results - Landscape Diversity Units
LDUs are the land-based units that form the core of the analysis of physical diversity. The number of LDUs occurring in the biophysical regions of Vermont varies from 586 in the Northeastern Highlands [thumbnail & link to garish NEH map] to 956 in the Northern Green Mountains (see table below). Mean LDU sizes ranged from 3.2 hectares in the Champlain Valley and the Southern Piedmont to 5.0 hectares in the Northeastern Highlands. The largest LDU patches in each region were hundreds of hectares, up to almost 1600 hectares in the Northern Green Mountains. It will surprise no one familiar with the landscapes of Vermont that the most common six or seven LDUs in every region, with one exception, represented hill landforms covered with glacial till. In fact, these "till and hill" LDUs (of varying lithologies, and mostly in the 800-2500 foot elevation range) occupy from about 54% (Taconics/Vermont Valley) to about 73% (Southern Green Mountains and Northern Piedmont) of the individual regions, and 61% of the state. The one exception, of course, is the Champlain Valley, where the most common LDUs are associated with gentler landscapes mantled with clays and sands deposited by glacial lakes and the Champlain Sea.
Number of unique landscape diversity units (LDUs) in the biophysical regions of Vermont, and mean and maximum LDU size (hectares).
| |
Biophysical Regionsa
| |
State
|
| |
TVV
|
SGM
|
SP
|
CV
|
NGM
|
NP
|
NEH
| |
All Regions
|
|
Number of unique LDU labels |
774 |
829 |
712 |
797 |
956 |
947 |
586 |
|
1784 |
|
Mean size |
3.5 |
4.6 |
3.2 |
3.2b |
4.1 |
3.8 |
5.0 |
|
3.9 |
|
Maximum size |
840 |
1064 |
811 |
1494b |
1596 |
1957 |
1143 |
|
1957 |
aAbbreviations for biophysical regions of Vermont are: TVV = Taconics/VT Valley, SGM = Southern Green Mountains, SP = Southern Piedmont, CV = Champlain Valley, NGM = Northern Green Mountains, NP = Northern Piedmont, NEH = Northeastern Highlands.
bLake Champlain LDU was excluded.
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