Giuliana Dehn, University of Konstanz, giuliana.dehn@uni-konstanz.de
Isabel Piljek, University of Konstanz, isabel.piljek@uni-konstanz.de
Jannik Frauendorf, University of Konstanz, jannik.frauendorf@uni-konstanz.de PRIMARY
Ziad Salem, University of Konstanz, ziad.salem@uni-konstanz.de
Yerzhan Niyazbayev, University of Konstanz, yerzhan.niyazbayev@uni-konstanz.de
Juri Buchmüller juri.buchmueller@uni-konstanz.de
Eren Cakmak eren.cakmak@uni-konstanz.de
Wolfgang Jentner wolfgang.jentner@uni-konstanz.de
Florian Stoffel florian.stoffel@uni-konstanz.de
Daniel Keim daniel.keim@uni-konstanz.de
Student Team: YES
Approximately how many hours were spent working on this submission in
total?
600 hours.
May we post your submission in the Visual Analytics Benchmark
Repository after VAST Challenge 2018 is complete? YES
Video
https://youtu.be/0ZmvjMNWAZ8
Link to PipitSaver.jar
https://drive.google.com/open?id=1ljqM7UqfXlOU-CYzNTI0Fdut3k2gP5-G
Questions
Tool description:
The left upper part shows the selected
measures which always maps the right upper visualization
(crystal view) and right bottom visualization (mosaic view). The crystal view
depicts boxplot similar visualizations for each selected measure. They are
scaled on a logarithmic base and
refer to the two time windows of the timeline in the
middle (stream graph). If a section is empty it means that at least one window
contains no samples. In order to only plot one time
window within the crystal objects the other time window can be deselected (see
in Figure 1_1, only window 1 is selected). In the middle of the crystal objects
the normalized variances are mapped to grey scales. Dark grey indicates a high
variance. The layout of the objects reflects the geographical situation of the
measuring stations on the map provided.
On the left side the options for the mosaic
view are available to switch the focus of the analysis. One can choose between
the number of measurements (grey) and the variances (orange). The values have
been aggregated into quarters to provide an overview of the entire period. The
values are displayed in the mosaic view on the right side. Sparklines show how
the number of measurements changes in relation to the previous quarter -
whether these increase,
decrease or stay constant.

Figure 1_1
1) Jumps of values at year turns:
Many measures’ values jump over the year turns
between 2007 and 2010. We suspect that this can be related to environmental
changes such as chemical contaminations. See Figure 1_2: The plotted measures
show huge value changes between 2007 and 2008. Especially Atrazine and Endrine, since there is no value range, but thin lines.
This means that the values were stable and jumped to new stable values.

Figure 1_2
See
Figure 1_3: The plotted measures show huge value changes between 2008 and 2009.
The most significant jumps are the decreasing values of Isodrin
and Hexachlorobenzene in Kohsoom.

Figure 1_3
Between
2009 and 2010 we also have these value changes: The measure
gamma-Hexachlorocyclohexane, which is dangerous for the environment, increased
in every location where samples have been taken. It is possible that the
measure was distributed over the air so that it reached all locations.
After
identifying these huge changes over three years, we checked for more details in
a scatter plot (see Figure 1_4) which also shows the jumps at a glance.

Figure 1_4
2) Dumps of Methylosmoline:
We suspect that the dumping of Methyosmoline started in the Christmas break between
2014/2015 when there are no/less Ranger patrols. The dumps were placed near the
marked location, see Figure 1_5.
There are different Methyosmoline
values per day in Chai; therefore, we assume, that the samples are taken from
different rivers 1 and 2 per day in Chai (see Figure 1_5).
Furthermore, We
assume that the contamination reached the marked revier
1 directly, resulting in a significant increase of Methyolosmoline
in Chai. The contamination also reached Kohsoom (and
later also Chai) with revier 2 slowly resulting in a
continuously parallel incline of the values. The proved dumps within the year
2015 and 2016 from the last year’s VAST Challenge cause a further increase at Kohsoom.
Moreover, the contamination is more
catastrophic than expected. We suspect that Kasios
company dumped also near Somchair in the Christmas
break 2014/2015 and dumped even a higher amount in the Christmas break
2015/2016.

Figure 1_5
3) Cover-up of illegal waste dumps:
It is visible at a glance that other measures
also show this break within the period of time:
First, the toxic Chlorodinine
is also constant for years and decreases to lower concentrations after year
turn 2015/2016.
Second, there is an immediate drop in
concentration of several other measures.
Third, there is an unusual peak of water
temperature recorded at the year turn 2015/2016 - in the middle of the winter!
These patterns lead to the assumption that the water was
manipulated. We assume that the Kasios company may diluted
the contaminated rivers with clean water in order to
conceal the illegal waste dumping.
Macrozoobenthos are indicators for high water quality. They have been
sampled in the past, but were unfortunately not
sampled in the contaminated locations. So it is not
possible to prove the harmful impact of Methyolsomoline.
Figure 1_6
and Figure 1_7 show interesting findings regarding suspicious measures which occured at the end of the sampling period.

Figure 1_6

Figure 1_7
4) Peaks of metal measures:
In the first nine years there were several
peaks of certain metals recorded. One of these peaks also contains the highest
value in the entire data set (Iron in Kohsoom).

Figure 1_8
5) Correlation:
We used correlation statistic to measure the degree of the
relationship between measures. For example, in Achara
and Boonsri we found correlation between total
hardness and total dissolved salts, and between Sulphates and Sodium and etc. There are correlations between Bicarbonates,
Chlorides, Sulphates, and Sodium in Kohsoom and Boonsri. Fecal coliforms and
Total coliforms are correlated in Kannika. Iron and
Manganese are highly correlated in all four locations.

Figure 1_9
6) Variances:
Figure 1_10 shows chemicals within the mosaic
view, displaying the changes of variances over the whole time
period. Chemicals like Barium show high variances over the whole time of
their occurence. Arsenic show variances starting in
2008 and has its highest variance in Tansanee in
2015. Fecal coliforms and fecal
streptococci have the highest variances in Kohsoom
and Somchair and Iron has only high variances in one
quarter in 2003.

Figure 1_10
The dataset contains 106
chemicals, from 1998 to 2016 at 10 locations. 32900 measurements are
duplicates, were taken on same date and location and has the same value. The
dataset covers 28,3% of the whole time range.

Figure 2_1
By looking deeper, in
Figure 2_1, measurements were taken in Boonsri, Chai
and Kannika (from January 1998), and Busarakham, Kohsoom, Sakda and Somcha
ir (from
April 1998). Then the hydrology department improved the sampling through the
expansion of three new measurement locations (2009). Furthermore, substances
have been measured multiple times on the same date.

Figure 2_2
Between 2005 and 2010,
many duplicates, Figure 2_2, have been taken in Boonsri
and Chai, which explains the increase in the bottom of this figure. In 2016 the
measurements of water temperature (days per week) in Chai increased drastically.

Figure 2-3
Taking
a look at Figure 2_3 and
2_4, different patterns appear. The hydrology department does not collect sufficient data, that reflects the comprehensive situation.
Chemicals, like Dieldrin and Endrin (2_3A1) have been mainly measured between
2005 and 2007 and in the second half of 2009, containing only one value per
location. Aldrin has been measured more often and show also high variances
(2_3A2). Barium and Boron has only be sampled over a
small time period (2_3B1), but showing unstable behavior
(2_3B2). Whereas chemicals like AGOC-3A, Chlorodinine
and Methylosmoline only appear since 2014 (2_3C1),
also showing high variances (2_3C2).
The sampling of these
chemicals is not sufficient, as it does not cover the whole
time range. It seems, that the hydrology department discusses the
sampling strategy for the following year after each christmas
break, as changes mostly appear in the first quarter of a year.
Methylosmoline and AGOC-3A are not measured in the Achara, Decha and Tansanee.
So at first it seemed, that the sampling
situation improved by the additional locations, but important measure samples
are missing there. Additionally, the missing values and gaps do not allow a
continuous time analysis, making it hard to identify some patterns.

Figure 2_4
Sampling accuracy: For certain measures it seems that the values
are rounded (1998-2003), resulting in significant constant values. With the
begin of 2004, the accuracy is higher. We assume that more accurate sensors are
used. The rounding of measures makes an interpretation of the patterns and
developments difficult, e.g. detecting periodic data.

Figure 2_5
From Figure 2_6 we can see the 50 strongest rules with
regard to in 4 location. This analysis shows that the strategy for
taking samples is different based on the location. Within a location the rules
are very strong, i.e. the same set of measures are taken together with a
regular frequency. For instance in Boonsri, If {Ammonium,Calcium,Chemical Oxygen
Demand (Cr),Nitrates,Sulphates,Total dissolved salts
and Total phosphorus} are taken, then with 100% confidence the
{Orthophosphate-phosphorus} will be also taken.

Figure 2_6
Accordingly, the hydrology department has to improve the sampling strategy. Therefore, we have
four proposals that are described in Question 3.
The visualization in
Figure 3_1 depicts measures changing dramatically over the whole period of time. We figure that especially these developments
can have a big influence on the wildlife of the park because the developments
are ongoing processes that do not seem unstoppable. All five globally
increasing measures are substances downgrading the water quality. Increasing
numbers of visitors to the campsites and the newly built ranger station could
be the origin of increasing waste and fecal water.
This can have a threatening effect on bird populations and other wild animals.
Moreover, the highest value of total coliforms, which can cause serious illness
and infection symptoms, is taken in Kohsoom and
increases in many locations. Arsenic and Atrazine are also chemicals that are
dangerous for the environment and increase over all locations containing
samples. Also, all globally decreasing measures can have a huge influence on
the wildlife. The question arises whether the wildlife can adapt quickly enough
to the changes in the environment. Another reason for the steady change of the
measures can be a continuous increase of traffic in the wildlife preserve.
The waste dumping took
place between Kohsoom and Boonsri.
The chemicals are spreading through the river arms and pollute adjacent areas,
and as a result, the habitat of animals shrink. Chemicals can be detected in Somchair and contamination also occurs in Sakda. As these locations show similar behavior
in chemical contamination, which we assume is caused by the dumping of Methylosmoline, we accuse the Kasios
company of waste dumping in Somchair.

Figure 3_1
To improve the
sampling strategy we would suggest four approaches
concerning the sampling frequency, redundancies within samples, measure
stations and the toxicity of chemicals.
In
order to improve the sampling
strategy, it would be beneficial to take measures on a regular basis and take
samples from all locations on the same date. We identified samplings which have
same values that have been taken at same location and day.

Figure 3_2
Chemicals which are
detected as stable and which only change over long periods of time can be
sampled less frequent than chemicals showing interesting patterns. This saves
manpower, money and puts the focus on interesting chemicals.
To understand the
origin of contaminations, more measuring stations would be beneficial,
especially near suspicious areas. Furthermore, measurement stations are
presented in Figure 3_3. M1 is near the dumping area and with
this measurement station the impact on the river branches between Boonsri and Kohsoom can be
further analyzed. Another interesting location to
prove the occurrence of Methylosmoline is the
location Somchair. By additional stations M2 and M3,
the contamination can be further circumscribed, as it is not clear wether something happened at Somchair
or if substances are at the lake above or in previous river branches.
The final proposal is
to supply a scale that provides information on how toxic different substances
are and in what concentrations they become dangerous. This helps to examine
negative impacts on the water quality using Visual Analytics.

Figure 3_3