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In page Landscape architecture:

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Ian McHarg was known for introducing environmental concerns in landscape architecture.[5][6] He popularized a system of analyzing the layers of a site in order to compile a complete understanding of the qualitative attributes of a place. This system became the foundation of today's Geographic Information Systems (GIS). McHarg would give every qualitative aspect of the site a layer, such as the history, hydrology, topography, vegetation, etc. GIS software is ubiquitously used in the landscape architecture profession today to analyze materials in and on the Earth's surface and is similarly used by urban planners, geographers, forestry and natural resources professionals, etc.[citation needed]