As
Geographers we are constantly looking for new and interesting ways to define
the world and the environment that we live in. Geography is a huge subject that can encompass many different scientific practices. However each
of these practices will have to follow basic rules to collect data. In the
Geographic Field Survey course we are tasked with utilizing different methods
of sampling techniques to create and collect data. By using our sampling
systems correctly we will be able to utilize our time, energy, money, and man power effectively. Sampling will be used to collect data. The sampling
methods that we will utilize can either be random, systematic or stratified.
Random sampling is the best method to collect data without bias while
systematic can collect data based on a set criteria. Stratified can be used
with both random or systematic sampling but the areas in the field of interest
must be known and must be quantitatively utilized in order to make stratified
sampling useful.
The
objectives of this lab are to use a 2.34m x 1.12m sandbox to create five
geomorphic models and utilize a grid system with a sampling method which will later be incorporated into a
program such as Arc GIS or excel to create a three dimensional model of the
collected data. In order to complete this survey we will have to create a
spreadsheet of data with fields in X,Y, and Z.
Methods:
To complete the objectives the group
decided to use snow to build the five geomorphic models. The models include
a ridge, a large mountain, a valley, a depression and finally a plain area. In
order to collect data from a sampling method the group used twine and
thumbtacks to create a grid system which was 10cm x 10cm. This grid size will give us a large area to work with and be very accurate with numerous sampling sizes. we opted to use a
systematic sampling approach to collect data since it will be the best use of
our time and resources.
Creating the study area
The grid will assign each square its own x, and y
value. To create the Z coordinate we went through each square and
measured in cm to the wooden barrier around the sandbox. This was to be the sea
level. While two people measure the Z coordinate in each grid one
person had a spreadsheet created with labeled areas to create a quantitative
graph of each area which would be later incorporated into a excel sheet.
Results:
The resulting numbers of the 10cm x 10cm grid were numerous.
To create a good sampling system we are supposed to have a great number of
samples since the x value is 23 by a y or 11 we collected a total of 242
samples to give us a good sampling base.
The Grid system is built and ready to collect data
The minimum sample collected was -17.5
and the maximum was 20 when we look at a color coded excel sheet we can begin
to notice a pattern in the data already with the ridge and the mountain
becoming evident on the placement in the grid system as positive areas and the
depression and valley as negative. With this data it will be very interesting
to see the final product when we incorporate it into Arc GIS for a full three
dimension look at the data
Conclusion:
In conclusion we were able to create a spatial model by
thinking critically and using the data and equipment that was provided to us.
By using a grid system in a 10cm x 10cm format we were able to create and
collect a satisfying amount of data by using a systematic sampling method which
can be used later in excel and Arc GIS.
Collected data shows the ridge, mountain, valley and depression
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