Quantifying Urbanization and Fragmentation of Agricultural and Forested Lands in Kenosha County 1988-2008

Abstract

Kenosha County’s proximity to Milwaukee and Chicago limited industry to manufacturing in the 20th century. In the past two decades Kenosha has increased its role in commercial economy. This resulted in changes in land use which impacted agricultural and forested lands. Kenosha’s agricultural lands are of both state and national importance for food production. Forests are useful for their aesthetic appeal, recreational purposes, as an aid to prevent runoff, and as storage for environmental carbon. Due to changes in the economy and their resulting changes on the physical environment, it was hypothesized that there has been a higher percent of agricultural and forested land converted to residential and commercial uses in Kenosha County between 1988 and 2008 along Interstate 94 and in townships which share a boundary with Illinois compared to Kenosha County as a whole. It was also hypothesized that county subdivisions (towns, villages, or cities) with greater population growth exhibited higher levels of fragmentation of agricultural and forested land. To quantify and spatially analyze changes in Kenosha, two classified land cover/use maps were derived from satellite images of 1988 and 2008 respectively using Idrisi image processing software. Both 1988 and 2008 classifications yielded 75% accuracy. Idrisi’s Land Change Modeler was used to quantify the change in area from one land use/cover to another. Percent changes along I-94 were not higher than those of the whole county for both agriculture and farmland and only a portion of the subdivisions on the Illinois border exhibited greater changes in the two specified classes than the county as a whole. Fragmentation of agricultural and forested lands was calculated using spatial metrics from Fragstats software. As hypothesized, the subdivision with the greatest population growth also exhibited more fragmentation between 1988 and 2008. This study serves as an evaluation of the changing landscape of Kenosha since the County’s 1991 Corridor Plan, provides useful insights for the 2035 Zoning Plan and will potentially advocate for increased conservation of important forested and agricultural lands.