GIS in W=
ater
Resources
There
are three questions on this exam. Do
all three questions. For the first=
two
questions, prepare a 2-page typed theme paper.
For the third question use ArcGIS (and Excel/Word) to prepare the map
and answers requested. Staple a=
ll
three solutions together in the order of the questions, and turn in the
result to the EWRE secretary (Rebecca Christian) or to Dr Maidment in ECJ 8=
.612,
by 5PM on Thursday, December 11. T=
his is
a take-home exam. You are honor bo=
und
not to discuss this exam with your colleagues in the class. Your answers should be the result of yo=
ur
work and thought alone. Be assured=
that
if essentially the same idea appears in answers from more than one person, =
it
is fairly easy to recognize that when the grading is being done. If that happens, it is not clear from w=
hom
the idea originated and who is just using somebody else’s knowledge. So, keep your ideas to yourself!
The
term papers that you choose to describe in answering Questions 1 and 2 shou=
ld
be mutually exclusive, that is, if you focus on particular term papers in
answering one of the questions, don’t focus on the same papers when answeri=
ng
the other question. The Texas clas=
s term
project listing can be found at: http://www.ce.utexas.e=
du/prof/maidment/giswr2008/docs/termprojlist.htm. The Utah class term project listing can=
be
found at: http://www.engineering=
.usu.edu/dtarb/giswr/2008/students.html. The Nebraska class term project listing=
can
be found at:
http://www.snr.unl.e=
du/airmak/termproject.htm.
You are encourag=
ed to
use projects from the three locations in preparing your answers since this =
will
give you a greater body of information to speak from.
What
we are looking for in grading your answers to the first two questions is:
· =
· =
Choose
two term papers that deal with the same or similar themes or topics. Neither of these papers should be your =
own
term paper. Briefly summarize the
contents of the papers (the problem examined, the method of analysis, the
results achieved). Compare and co=
ntrast
the approaches to the problem that the two papers took. Which technical approach do you think w=
as
more effective? Why? Which paper does a more effective job of
communicating its results? Why?
2. Writ=
e an
Assessment of the Utility of GIS in a Particular Application Area
Student
term papers on a range of topics have been presented. Select four papers that fall within a s=
imilar
subject area and present a critique of how effective GIS is
in its application in this subject area.
What is the scope of the application area? How has GIS been used? What types of problems have been solved
effectively? What limitations exis=
t that
have yet to be overcome in the application of GIS in this area? In
your answer, you must refer specifically to work presented in term papers
prepared in this course. In ot=
her
words, I am not looking here just for a general statement about your opinio=
ns
in the field but rather a deduction based on the term papers presented in t=
his
class of what has been done and how you judge the effectiveness of that.
3. San =
Marcos
Basin Geomorphology
Background
and Context. Digital elevation models provide the
opportunity to explore the geomorphology of a region. This problem will use the ArcGIS and Ar=
cHydro
tools to perform some geomorphologic analyses on the San Marcos digital
elevation model.
Question. The zi= p file (ht= tp://www.ce.utexas.edu/prof/maidment/giswr2008/exam/final.zip) contains the DEM and a geodatabase with monitoring points. This data is similar to that used in the class, except that the DEM is projected onto a 30 m resolution grid and a T= exas Albers projection is used for both the DEM and the monitoring points which = are a subset of those used in class. <= o:p>
a)&n= bsp; Use the Arc= Hydro tools to delineate the watersheds draining to each of the monitoring points= in the provided MonitoringPoints feature class. Note that here watershed refers to the entire area draining to a monitoring point as illustrated. <= o:p>
You
do not need to burn in existing streams for this exerci=
se,
rather streams should be delineated based on the DEM alone. Prepare a table that for each watershed
reports the following:
-&nb=
sp;
Name
-&nb=
sp;
Drainage ar=
ea (km2)
-&nb= sp; Mean slope<= o:p>
-&nb=
sp;
Mean elevat=
ion
(m)
-&nb=
sp;
Elevation r=
ange
(Max elevation – Min elevation in m)
-&nb=
sp;
Relative re=
lief
(This is elevation range divided by the square root of the drainage area.
In
summarizing this information over watersheds ensure that in the methods and
functions that you use that you obtain results that pertain to each entire
watershed recognizing the overlap, with the two smaller watersheds being
contained within the larger one. T=
he
relative relief provides a dimensionless measure of the ruggedness of the
topography. Prepare a layout where=
you
depict the topography and watershed boundaries.
Label the watershed with the highest and lowest relative relief and
indicate whether these relative relief measures make sense given the
topography.
b)&n=
bsp;
How does dr=
ainage
density depend upon stream definition threshold? To address this question identify the m=
ost
downstream monitoring point and use the watershed draining to this point to
clip the DEM so that it contains only the area within this watershed.
Delineate
drainage lines over the clipped DEM for each of the following stream defini=
tion
thresholds (in numbers of grid cells): 200, 500, 2000, 10000, 40000. Prepare a table that gives for each str=
eam
definition threshold the following:
-&nb=
sp;
Stream defi=
nition
threshold (number of cells)
-&nb=
sp;
Stream defi=
nition
threshold area (km2)
-&nb=
sp;
Total drain=
age
line length
-&nb=
sp;
Number of
drainage lines
-&nb=
sp;
Drainage ar=
ea (km2)
-&nb=
sp;
Drainage de=
nsity
(km-1)
Prepare
a log-log plot of Drainage density, Dd, (y-axis) versus stream definition t=
hreshold
area, Ac, (x-axis). Fit a power law
relationship to this data and report the coefficients a=
and
b in the equation (