Analyze the land around a property
This section describes ways that GIS can help you understand the context of a property
GIS can help with property acquisition and with site stewardship, but it can also help define relationships between a property and its surroundings. Here are some useful approaches to this type of analysis:
1. Viewsheds: What can be seen on your property and what you can see from your property are important topics, particularly for areas where there are long vistas. With topographic data (a DEM) and advanced GIS software, you can generate "viewsheds" for particular properties or along defined routes. This can be particularly useful if, for example, you are protecting landscapes visible from a scenic highway, or within site of a particular vista point.
You can also use this technique to help select property owners names who are within the viewshed of a potential acquisition - this list can help support funding or other involvement in a protection campaign. It can also be used in stewardship, to determine where to allow any buildings or changes to your properties, or to assess the impact from a neighboring parcel.
2. Demographics: In more suburbanized areas or in cities, finding out who lives nearby can be crucial for acquisition campaigns, site planning and general outreach. Using readily available demographic data and applying a GIS technique known as buffer analysis, you can generate detailed profiles of the populations near your holding. For example, are you hoping to establish a park that will be accessible to communities of need? You can create a buffer (maybe 1/4-mile or 1/2-mile if a small, neighborhood park; up to 5-miles if a larger regional park) around the park site. Then use this buffer to select all Census tracts or block groups within the specified distance of the park, and use summary functions on this subset to calculate statistics such as median household income, percent breakdown by ethnic group, and percent of children in poverty. This information can be critical in talking with funders and doing outreach in the communities you serve.
You can work with demographics on a more advanced level by better defining your service area (using concepts like driving times, transit routes, and access points) or examining park access within a community as a whole (identifying "hot spots" of need). Both are potentially useful analyses for more strategic planning.
3. Watershed assessment: In the context of a watershed, what happens on an individual property may affect more than just that property and those immediately adjacent, it may impact all properties and resources downstream. For example, proposed development on one tract of land can impact the water quality of all areas that water from that development flows into - even many miles away. GIS can be used to establish these upstream/downstream connections based on the topography of the watershed or a defined hydrologic network, allowing you to trace the impacts of activities on one property to others within the watershed.
The ESRI Guide to GIS Analysis, Volumes 1 and 2 - outstanding books explaining basic and advanced GIS analysis
ESRI Virtual Campus - online classes, including training in advanced GIS analysis
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