Monday, May 12, 2014

GIS I Lab 5 - Applying Geospatial Skills

Introduction:


This final lab called for the student to design their own research question that they could solve using geospatial tools within ArcGis. The research question that was thought of was; where is the best place to build a cabin in southwestern Wisconsin? In order to come up with the desired locations, there were a few parameters that needed to be set. It needed to be located in deer management zone 61, but only in Buffalo, Pepin or Trempealeau counties. The location also needed to be within 20 miles of the Mississippi River and at least 2 miles away from a major highway. People that may use this information may want to know where to build a cabin that would give them some solitude for a weekend get a way. Deer hunters who hunt in the deer management zone 61 may also be interested in this type of information.

Data Sources:

 In order to obtain an answer to this question, it was necessary to get data from a couple of different sources. The data was obtained by establishing database connections through ArcGIS. There were two different connections that needed to be made. The first was with the ESRI database and the second was with the Wisconsin DNR database. In order to get an answer to the question being asked, it was necessary to obtain data from both databases. The ESRI database provided the information regarding the state and county boundaries as well as the major highways. The Wisconsin database provided information that showed the different deer management zones as well as the Mississippi River.

Once all the data was on the map, it needed to be analyzed for possible problems it may have. The data sets appeared to be complete and it seemed to be reliable. After taking a closer look, the first concern that appeared was the consistency as to when it was updated. All of the data from the ESRI database is updated annually. There should be little concern with how up to date their data is, since it is updated every year. The Wisconsin DNR data on the other hand, did not specify when it was updated or how often. This could cause problems if some of the data sets had changed and there were different boundaries in present time. Without knowing how often this data is updated may cause for an irrelevant map to be made from outdated data.

The second major concern about the data is noticed by looking at the map. All of the boundaries do not line up perfectly. There also seems to be gaps within the southern portion of the map. This could cause for some areas to not be mapped that should have been included in the study area. 

Methods:

This is the work flow model that was used to obtain the answer to the question being asked.

The first step in answering this question was to narrow down the map to the selected area of interest. The states layer needed to be queried in order to make Wisconsin its own layer. Once that was done, it was clipped with USA counties in order to have the state of Wisconsin with all of its counties shown on the map.
 
The Deer management zones needed to be added to the map and queried as well. This allowed for zone 61 to be selected and shown individually on the map. Once a new feature class was made with management zone 61, it was then clipped with Wisconsin counties in order to get the larger area of interest. With the area of interest located, it needed to be narrowed down one more time. An attribute query needed to be done in order to locate where the desired counties were located within the deer management zone 61.

The next step was to select the Mississippi River from the Wisconsin Hydroflow data. Once it was selected, a new feature class of just the Mississippi River needed to be made for future use. A 20 mile buffer needed to then be made around the Mississippi River in order to see where a potential cabin could be built. Since the Mississippi River borders more than the three desired counties, the buffer needed to be clipped by the desired counties feature class. The result of this process only showed the buffer around the Mississippi within the desired counties.

The major highway feature class also needed to be narrowed down to the study area. The major highways were clipped by the desired counties in order to just have the highways in the desired counties visible on the map. Once the highways were clipped, a two mile buffer was needed around all of them.  This buffer showed where a cabin could NOT be located. An erase had to be used in order to eliminate the buffer around the highway, but show everything beyond 2 miles of a highway.

The result of the erase was then intersected with the Mississippi River buffer. It needed to be intersected in order to show where the ideal hunting cabin would be located in the deer management zone 61.

Results:

 This map shows the ideal hunting cabin locations within deer managment zone 61.


The results of this project are very interesting. Most of the ideal cabin locations are located in the central part of the study area. The highest amount of possible cabin locations are in Buffalo County. This is somewhat expected since it is the largest county in the study area. It is also interesting to see where the major highways were located and where the buffer from the Mississippi River cut off. There seems to be a major highway running along the Mississippi River with different highways branching off from it at different points. In the northeastern portion of the study area there is not many possible cabin locations. This is due to the Mississippi River buffer not reaching that far. Therefore, it automatically eliminates it from being a possible cabin site.

Evaluation:

This assignment allowed for the student to create their own project in their area of interest and use all the GIS tools they have learned throughout the semester. The assignment made the student come up with a real life geospatial question that needed to be solved. Critical thinking was needed in order to figure out which tools would yield the result the student desired in order to get the result that was wanted. If I were to do the assignment over, there would be more criteria involved. That would narrow down the ideal cabin locations and not give as general of a result. 

Sources:

Esri Database

Wisconsin DNR Database