Occurence of Terrestrial Microplastics in Agricultural Ecosystems

Jonessa Haas Author

07/31/2020 Added

9 Plays

Description

This presentation summarizes my research this summer on microplastics found in freshwater environments.

Searchable Transcript

Search:

[00:00:00.389]Hello, my name is Jonessa Haas
[00:00:02.389]and I am an REU student at the
[00:00:04.379]University of Nebraska-Lincoln
[00:00:06.329]and have been conducting research under
[00:00:08.135]Dr. Shannon Bartelt-Hunt in the
[00:00:09.585]sustainability department.
[00:00:11.680]We have been researching the occurrence
[00:00:13.730]of microplastics in agricultural environments.
[00:00:16.470]I'll go into a short introduction,
[00:00:18.440]talk about the purpose of the research,
[00:00:20.110]and then get into the methods of
[00:00:21.470]data collection, results, and a couple
[00:00:23.550]of conclusions we came up with after
[00:00:25.320]analyzing the data.
[00:00:27.321]Our motivation for this research
[00:00:29.381]comes from the increasing concern
[00:00:31.120]we have about microplastics in the
[00:00:33.130]environment.
[00:00:34.270]There's a lot of information on
[00:00:35.780]plastics in marine ecosystems but
[00:00:38.360]microplastics particles exist in rivers,
[00:00:40.980]lakes, soil and wastewater as well.
[00:00:44.196]This graph is from the EPA website
[00:00:46.376]and it shows plastic waste trends
[00:00:48.396]over the past 60 years.
[00:00:50.163]As you can see, more and more
[00:00:52.104]plastic is disposed of every year
[00:00:54.307]but it also bring up the question
[00:00:56.277]of; How much wasted plastic
[00:00:58.178]is not making it into these systems
[00:01:00.298]and is actually ending up in
[00:01:02.188]natural systems?
[00:01:04.609]The main purpose of my research
[00:01:06.529]this summer was to summarize data
[00:01:08.349]found in studies relating to microplastics
[00:01:10.419]in freshwater environments,
[00:01:12.200]so that is could act as a foundation
[00:01:14.350]for future research.
[00:01:15.929]That being said, I did analyze the
[00:01:17.749]data myself and came up with a
[00:01:19.288]couple of interesting conclusions.
[00:01:21.750]My method of research was to
[00:01:23.470]read as many article as I could
[00:01:25.180]that related to microplastics
[00:01:26.940]in freshwater environments.
[00:01:28.866]I was given a few papers to start with
[00:01:30.726]and then expanded my search by
[00:01:32.466]finding the papers that the original
[00:01:34.426]material had referenced.
[00:01:36.076]This was a pretty lengthy process because
[00:01:38.176]a lot of the material that I thought would
[00:01:40.366]be relevant ended up being more like
[00:01:42.266]a stepping-stone to the papers
[00:01:43.776]I actually wanted.
[00:01:45.270]After finding around 20 or so papers
[00:01:47.570]with the data I was looking for
[00:01:49.430]I started inputting information into excel.
[00:01:52.676]The image on the screen is a snapshot
[00:01:55.016]of my finalized table.
[00:01:57.264]I recorded locations, population, water type
[00:02:00.764]sample type, and a bunch of other things.
[00:02:04.183]As you may expected, not all of the
[00:02:06.293]data was expressed in the same way.
[00:02:08.768]So before I started making graphs,
[00:02:10.778]I need to make all of the data uniform
[00:02:13.157]For example, the concentration of
[00:02:15.137]microplastics in water was sometimes
[00:02:17.287]recorded as particles per meter cubed
[00:02:19.537]and other times particles per liter.
[00:02:22.241]That was an easy fix because the
[00:02:24.331]conversion was simple but
[00:02:26.131]size distribution was a little bit different.
[00:02:28.782]Almost all of the papers agreed
[00:02:30.772]that a microplastic was defined
[00:02:32.792]as a particle with the longest dimension
[00:02:35.202]being less than 5mm.
[00:02:37.632]But the subgroups were not uniform.
[00:02:40.782]This lead me to separating sizes
[00:02:43.032]into only 2 subgroups to accurately
[00:02:45.052]represent all of the data.
[00:02:47.060]I wish I would have been able to have
[00:02:49.340]more subgroups. I think if data is
[00:02:51.870]more specific it is more useful but
[00:02:55.180]there was no way for me to comfortably
[00:02:58.274]distribute the size percentages
[00:03:00.274]into more than two groups.
[00:03:02.563]After that process, I was able to
[00:03:04.653]start making graphs.
[00:03:06.291]There was some trial and error.
[00:03:08.231]I made several graphs that did not
[00:03:10.331]make so much sense.
[00:03:11.951]And at the very least, needed
[00:03:13.431]some more data.
[00:03:15.141]So I decided to go back and
[00:03:16.881]find a few more papers to fill
[00:03:18.791]in some of the gaps.
[00:03:20.262]In the end, I had about 24 papers
[00:03:22.332]that contributed to my final graphs.
[00:03:25.874]This is my first graph and as you can
[00:03:27.944]see, it's microparticle size distribution
[00:03:30.364]at various locations
[00:03:33.035]Almost all of the locations have more than
[00:03:35.530]50% of their microplastics in the
[00:03:38.010]less than 1000 micrometer group
[00:03:40.536]As indicated by the blue.
[00:03:42.707]The obvious reason why the distribution
[00:03:44.967]is skewed the way it is, is becuase
[00:03:47.117]there are in fact more small particles
[00:03:49.357]than large particles.
[00:03:51.591]And logically this kind of make sense.
[00:03:54.289]If you're given 2 pieces of paper and
[00:03:56.888]asked to cut out 1 inch squares with one
[00:03:59.258]sheet and 10 inch squares with the other
[00:04:01.198]sheet, you'll have the same amount of
[00:04:03.478]material but there will be more
[00:04:05.418]one inch squares.
[00:04:07.423]Another reason that there's a higher
[00:04:09.523]number of small particles could be a
[00:04:12.833]result of how the samples were taken.
[00:04:15.215]Larger particles could be located near
[00:04:17.575]the surface of the water.
[00:04:19.402]So if a sample is taken near the
[00:04:21.122]bottom of a river or lake
[00:04:24.150]it's not including the micropartilces
[00:04:26.450]at the top.
[00:04:28.123]Finally, I'd like to point out that
[00:04:30.143]the three locations with the highest
[00:04:32.353]percentages of large particles
[00:04:34.933]are all in America.
[00:04:36.855]This could be because a difference in
[00:04:39.285]how samples are taken
[00:04:41.274]Or it could indicate that the
[00:04:43.024]decomposition of plastic is different
[00:04:45.294]depending on location.
[00:04:47.631]For these two graphs some of the
[00:04:49.611]trends are a little abstract.
[00:04:51.895]These are the graphs I actually
[00:04:53.825]went and got some more data for,
[00:04:56.184]but personally I think that even more
[00:04:59.514]data would be beneficial.
[00:05:02.091]That being said, there are some
[00:05:04.051]interesting observations that can be made.
[00:05:06.591]In Figure 4, especially for the European
[00:05:09.161]data points. It seems that concentration
[00:05:11.891]decreases as population increases.
[00:05:15.344]This could be a result of better plastic
[00:05:17.904]disposal and/or wastewater treatment
[00:05:21.574]in more populated areas.
[00:05:24.152]Figure 5 follows the same logic for
[00:05:26.750]natural water sources and sediments but,
[00:05:29.640]the concentration of microplastics
[00:05:32.270]increase with populations for the
[00:05:34.750]wastewater samples.
[00:05:37.697]These last 2 graphs are depicting the
[00:05:39.707]resins that were most prevalent in each
[00:05:41.617]study and categorized by continent
[00:05:43.847]and sample type.
[00:05:45.340]Polyethylene and polypropylene were
[00:05:47.580]the top results overall, but there are some
[00:05:50.080]differences if we take a closer look.
[00:05:53.002]Europe's top result was PE but it's second
[00:05:55.902]most common resin was polyester.
[00:05:58.713]This could be the result of different
[00:06:00.843]countries using different plastics in
[00:06:02.883]everyday life or industry practices.
[00:06:05.918]Figure 7 shows wastewater also having
[00:06:09.958]PE as its most common resin and
[00:06:12.088]polyester as it's second.
[00:06:14.036]This could suggest that the wastewater
[00:06:16.306]systems do not remove polyester efficiently
[00:06:19.926]or because Europe has high amounts of
[00:06:23.366]polyester it could isolate European
[00:06:25.626]countries as not not having efficient
[00:06:27.806]removal of the resin.
[00:06:31.152]In summary, there were a lot of
[00:06:33.002]notable differences in microplastic size,
[00:06:35.452]concentration, and resin type
[00:06:37.392]based on location.
[00:06:39.276]And before creating the graphs, I had
[00:06:41.506]expected a difference in results based
[00:06:44.746]on sample type, but it was interesting
[00:06:46.656]to see concentration of microplastics
[00:06:49.346]increase, in wastewater, as population
[00:06:52.711]increased.
[00:06:54.169]I think my research is a good start to
[00:06:56.289]summarizing data related to microplastics
[00:06:58.729]in the terrestrial/freshwater world.
[00:07:01.769]And the biggest hope is that it will help
[00:07:04.079]future researchers understand what
[00:07:06.279]they're working with.
[00:07:07.815]I really enjoyed this research and I'm
[00:07:10.025]coming out of it with a lot more questions
[00:07:12.435]than I had going in and honestly I think
[00:07:14.735]that's great. I really appreciate the
[00:07:17.105]opportunity to get to do this and I look
[00:07:19.385]forward to your questions. Thank you!

The screen size you are trying to search captions on is too small!

You can always jump over to MediaHub and check it out there.

Comments

0 Comments

Occurence of Terrestrial Microplastics in Agricultural Ecosystems

Description

Searchable Transcript

Comments icon comment

Related Channels

Comments