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3.2 Urban Projection Two methods were used to determine the amount of land that was expected to transition to urban over the ten-year period. The first method used historical land cover data. Specifically, the urban transformation number between 1990 and 1999 was calculated using these land cover maps from these two points in time. Future transition numbers were determined by assuming the same number of cells will transition to urban in the next such time interval. More specifically, the number of urban transition based on our 1990 and 1999 land cover maps is 5692 cells, a 13.05% increase from that of 1990. However, by subtracting those cells located in the exclusionary layer, the final estimated transi- tion number for 1990-99 was 4384. Figure 8 shows the real urban change from 1990 to 1999 in red. The second method to identify transition extent (see User Guide [11]) was calculating the principle index driver (PID) based on the population growth over a time interval fro a region. U(t) = (dP/dt) * A(t), where U is the amount of new urban land required in the time interval t, P is the number of new people in any given area in a given time interval and A is the per capita requirements for urban land. Unfortu- nately, this method is most effective with land use change and other data based on municipal bound- aries, since the population census is also based on municipal boundaries with different levels (block, track, parcel). For our study area, we were only able to calculate the normalized numbers (e.g. density, percentage) by assuming an even distribu- tion of population within each block. For instance, from 1990 to 2000, the population growth over the Land Transformation Model Figure 8. Urban expansion (red) within study area from 1990 to 1999 Detroit Lakes Area 11

Land Transformation Model - Center for Changing … · (see User Guide [11]) was calculating the principle index driver (PID) based on the population growth over a time interval fro

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3.2 Urban ProjectionTwo methods were used to determine the amountof land that was expected to transition to urbanover the ten-year period. The first method usedhistorical land cover data. Specifically, the urbantransformation number between 1990 and 1999was calculated using these land cover maps fromthese two points in time. Future transition numberswere determined by assuming the same number ofcells will transition to urban in the next such timeinterval. More specifically, the number of urbantransition based on our 1990 and 1999 land covermaps is 5692 cells, a 13.05% increase from that of1990. However, by subtracting those cells locatedin the exclusionary layer, the final estimated transi-tion number for 1990-99 was 4384. Figure 8shows the real urban change from 1990 to 1999 inred.

The second method to identify transition extent(see User Guide [11]) was calculating the principleindex driver (PID) based on the population growthover a time interval fro a region. U(t) = (dP/dt) * A(t),where U is the amount of new urban land requiredin the time interval t, P is the number of new peoplein any given area in a given time interval and A isthe per capita requirements for urban land. Unfortu-nately, this method is most effective with land usechange and other data based on municipal bound-aries, since the population census is also based onmunicipal boundaries with different levels (block,track, parcel). For our study area, we were onlyable to calculate the normalized numbers (e.g.density, percentage) by assuming an even distribu-tion of population within each block. For instance,from 1990 to 2000, the population growth over the

Land Transformation Model

Figure 8. Urban expansion (red) within study area from 1990 to 1999

Detroit LakesArea

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4. Model EvaluationThe modeled urban projection for 1999 based on1990’s land cover was overlaid with observedchanges in from 1990 and 1999 based on the two-year’s land cover maps. Then, a layer was created

with accuracy test information. In this layer, each cell has valueranging from 0 to 3. A designation of “0” means no predictedchange and no observed change; “1” means no predicted changebut there is observed change; “2” means no observed change butthere is predicted change; “3” means predicted change and ob-served change. In our study area, for the 4500 projected trans-formed cells, 1552 cells were projected correctly, which gives us a34.5 % accuracy. Given the history of use of the LTM model, thislevel of accuracy is considered typical. Accuracies exceeding 45-50 % are considered very unusual and perhaps due to over-fitting(to local circumstances) of the model. However, more detail onlocal cells, processes, and constraints, would likely improve classifi-cations. Of course, coarser or finer breakdowns of results (groupsof cells) might show higher or lower accuracy.

Among the 10-predictor variables, distance to lake, distance tomunicipal boundary, and distances to highway were the most in-structive variables. Distance to lowland was also considered aninstructive variable. Distance to stream and aspect were among theleast ineffective variables.

Figure 9. Future Land Transformaion within study area in 2010 and 2020.

Figure 9 shows the pre-dicted future land transfor-mation from non-urban tourban for years 2010 and2020. Transformed land isconcentrated around areasof existing population anddevelopment.

A more detailed look at theLTM results should provideuseful information relating tofuture development patternsnear the Lake CountryScenic Byway.

10 year interval was (38166-33366)/33366 =14.39%. We note this calculation matches theurban increase number very well.

Given the difficulty in matching census data withGIS cell data precisely, we used the first method(based on the observed land use change) ratherthan the second. For each 10-year interval, thecell number set to be transformed was 4500.Figure 9 shows the urban projection of 2010 and2020, based on the first method. Figures 10 - 14show more detailed urban projections around fivecommunities—Detroit Lakes, Park Rapids,Nevis, Akeley, and Walker.

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Land Transformation Model - WEST

Figure 10. West landscape type which includes Detroit Lakes

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Tamarak Wildlife Refuge

Tamarak Wildlife Refuge

Rolling hills w/ grazing land and patches of deciduous trees

Western landscapes

• Agrarian plains and communities of the RedRiver Valley

• Continental divide• Scattered hardwoods and expansive open

space• Rolling hills and undeveloped terrain• Smoky Hill State Forest• Tamarac National Wildlife Refuge (best birding

watching in the country)

Detroit Lakes public beach

Smokey Hill State Forest

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Land Transformation Model - South

Figure 11. South landscape type which includes Park Rapids

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Southern landscapes

• Transition from open plain to pine forests• Distinct small town charm• Quiet, dispersed development and small

logging/farming operations• Interconnected lakes and streams

Pedestrian bridge on Fishhook Lake inPark Rapids

Monument to Paul Bunyan in Akeley

Southwest entrance to Nevis

Paul Bunyan regional trailhead at Nevis

Paul Bunyan regional trail in Nevis

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Land Transformation Model - north

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Northern landscapes

• Most unique landscapes• Itasca State Park preserves the original vegetation• Headwaters of the Mississippi River• High percentage of publicly-owned land

Headwaters of the Mississippi River atItasca State Park

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Land Transformation Model - East

Figure 13. East landscape includes the southwest Chippewa National Forest, the City of Walker and Leech Lake

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Eastern landscapes

• Small communities have long, loving connection to thewater and wood

• Extensive pine forests of the Chippewa NationalForest and the Paul Bunyan State Forest

• Some of the largest waters in the state (Leech Lake)• Strong yet diverse culture

Heritage fest at Walker

Lake Country Scenic Byway passing through ChippewaNational Forest

Leech Lake from Walker

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