Developed and vacant land (Piscataway) derived from TIGER and LANDSAT TM: Map

Comparison map (Piscataway) of developed and vacant land derived from TIGER and LANDSAT TM; the determination of the amounts of developed land can vary when LANDSAT TM data and the TIGER data are combined, and/or when different housing unit density thresholds are used.Although the LANDSAT TM data and the TIGER data are highly independent of each other, each type of data can be used, either alone or in combination, to map and compute areas of vacant and developed land. The determination of the amounts of developed land can vary when different data types are combined, and/or when different housing unit density thresholds are used. The increase in the estimated amount of developed land, when different housing unit densities are used in combination with the satellite data, is shown for the four municipalities in this map (gaspric2.gif) and gaspric1.gif, gaspric3.gif and gaspric4.gif. As a lower housing unit density threshold is used in conjunction with the LANDSAT TM data, the estimated amount of developed land within a municipality increases. The amount of developed land as a percentage of total land for Piscataway, while showing an increase in developed land, does not increase as dramatically as it does for Essex Fells (see gaspric2.gif map). This can be attributed to the fact that much of the housing development in Piscataway is of a younger age than that found in Essex Fells. The newer development in Piscataway, much of it recently converted farmland, lacks the tree cover that older municipalities such as Essex Fells have. The LANDSAT TM data detected much of the residential areas in Piscataway, while detecting virtually none in Essex Fells