I am interested in repeating the H2S measuring procedure as done in Bayou Savage with some modifications. Hydrothermal vents have been suggested as point sources, but I've noticed that this experiment takes place in a marsh. I'm assuming from my reading that this experiment is measuring H2S produced by anaerobic degradation of plant material by bacteria. What is a good set of criteria for identifying a wetland that will produce high amounts of H2S? Can you point me to any papers on this subject?
I live in the San Francisco bay area, so there may be many opportunities if brackish marshes can exhibit this behavior.
We're also considering a trip to a small hydrothermal vent, which could be dramatic... but it seems like it has less similarity to measuring pathologic conditions. Then again, there is not question of H2S so it would be a good demonstration. Welcome thoughts on this as well, would probably head out to the Lassen volcanic area and find a small somewhat isolate hot sulfur hot spring.
I'm hoping that Scott will jump in and give you a good description as he
gave me an excellent one when I asked a similar question. However, I can
point you to papers that he posted on the protocol research note that might
be helpful as a starting point:
http://publiclaboratory.org/notes/shannon/6-22-2012/h2s-test-experime....
I have a couple of research notes I still need to write up from that test
as well, I'll try and get those done tonight and will send you links just
so you have them as a reference.
Best, Shannon
On Wed, Jul 4, 2012 at 9:37 AM, Matthew <deepwin...@rhus.winterroot.net>wrote:
> I am interested in repeating the H2S measuring procedure as done in Bayou
> Savage with some modifications. Hydrothermal vents have been suggested as
> point sources, but I've noticed that this experiment takes place in a
> marsh. I'm assuming from my reading that this experiment is measuring H2S
> produced by anaerobic degradation of plant material by bacteria. What is a
> good set of criteria for identifying a wetland that will produce high
> amounts of H2S? Can you point me to any papers on this subject?
> I live in the San Francisco bay area, so there may be many opportunities
> if brackish marshes can exhibit this behavior.
> We're also considering a trip to a small hydrothermal vent, which could be
> dramatic... but it seems like it has less similarity to measuring
> pathologic conditions. Then again, there is not question of H2S so it
> would be a good demonstration. Welcome thoughts on this as well, would
> probably head out to the Lassen volcanic area and find a small somewhat
> isolate hot sulfur hot spring.
I'm away from my work computer for the day, but off my head hydrogen
sulfide is generated by certain bacteria in anoxic, reducing conditions in
wetland soils. it is toxic to plants as well, although wetland plants,
especially saline marsh plants, can tolerate it. I have much more
knowledge of plants than of soils and biochemistry, but here it goes.
Anyone on the list (Adam?) should feel free to correct me, most of my
knowledge comes from reading papers by Dr. Mendelssohn at LSU, and talking
to Dr Jenneke Visser at ULL about plants. There's one in particular that
i can forward later.
basically, if you have collapsing marshes, that are "waterlogged," the
soils are likely anoxic and reducing. if you step or stir the soil, and
gas bubbles up, and it smells like rotten eggs, the collapsed/ing marsh is
producing some amount of H2S. The amounts generated are very low compared
to industrial sources.
many marsh plants have an alternate metabolism for their roots, which are
often underwater, in low or no oxygen conditions. H2S screws with this
anaerobic metabolism. Often, sulfide is associated with saltwater, as
certain ocean salts carry the sulfur. saltmarsh plants are apparently more
capable of dealing with H2S. So my expectation is that salt marshes will
produce more H2S under the collapsing condition.
The site i picked i is not as salty as i would have liked, but I picked it
because it was one of the closest collapsed marsh sites to a highway. It
was bare of plants post Katrina, and has received saltwater from Katrina
and from a flawed management decision--to flood the polder it sits within
with 12 ppt saltwater from Lake Pontchartrain.
Shannon was inspired by our trip out to Big Branch, where I demonstrated
the need for marsh restoration in the area by stepping in the existing
waterlogged marsh, which bubbled furiously at each step, and stank of
rotten eggs ( i think i have some video of this on flickr). Bayou Sauvage
is not as "bubbly" as that site, but it's very accessible and bubbles. I
think you can see the white foam in some of our photos of Bayou Sauvage.
The marsh in Bayou Sauvage has already totally collapsed at least once--I
have this knowledge from trying to re-plant it post-Katrina. the area is
behind a levee and under pump--this hydrologic alteration has degraded the
soil conditions. The area is managed for ducks, not plants--and so the
polder is artificially flooded at times, because the migrating ducks like a
lot of standing water.
USFWS and NOSCB had planted bullrushes and *Spartina *grasses there (see my
2009 photos)-but they didn't take. *Typha* has naturally colonized the
area. *Typha *is a plant that is more agnostic of salted and anoxic and
sulfuric soil conditions and high water variability. Its presence, as well
as the site's history, indicated to me that this was a good site to try.
The site was under a drainage regime during our trial--the pumps were on.
the soil at bayou sauvage bubbles and smells a bit rotten eggy--but not as
much as Big Branch. it's a 60 min car ride and 45 min canoe into the site
at Big Branch, which takes at lot more planning.
if the strips aren't sensitive enough to pick up on the H2S that was
there--and i'll have to get to my work computer to give you the expected
numbers, I would try it again at a more brackish and bubbly site. i will
keep an eye out and ask around.
perhaps across the bayou from the wetland watchers site out of NORCO. Or
perhaps fountainbleu park a mile off the boardwalk, or off Hwy 11 on the
northshore. the trouble with the more brackish, waterlogged sites in LA
that i am familiar with is that most of the good and screwed up ones
require a boat (at least a pirogue) to access. The Woodlands Conservancy
soils definitely stank of rotten eggs, perhaps we can try there, even
though it's freshwater. That is a former swamp that has been severely
drained, and the soils have collapsed. The older trees are five feet in
the air.
Sara, Shannon, i will make a list of other possible sites to visit and
assess if we want to repeat this trial in a bubblier, stinkier site.
scott
On Wed, Jul 4, 2012 at 2:54 AM, Shannon Dosemagen <
> I'm hoping that Scott will jump in and give you a good description as he
> gave me an excellent one when I asked a similar question. However, I can
> point you to papers that he posted on the protocol research note that might
> be helpful as a starting point:
> http://publiclaboratory.org/notes/shannon/6-22-2012/h2s-test-experime....
> I have a couple of research notes I still need to write up from that test
> as well, I'll try and get those done tonight and will send you links just
> so you have them as a reference.
> Best, Shannon
> On Wed, Jul 4, 2012 at 9:37 AM, Matthew <deepwin...@rhus.winterroot.net>wrote:
>> I am interested in repeating the H2S measuring procedure as done in Bayou
>> Savage with some modifications. Hydrothermal vents have been suggested as
>> point sources, but I've noticed that this experiment takes place in a
>> marsh. I'm assuming from my reading that this experiment is measuring H2S
>> produced by anaerobic degradation of plant material by bacteria. What is a
>> good set of criteria for identifying a wetland that will produce high
>> amounts of H2S? Can you point me to any papers on this subject?
>> I live in the San Francisco bay area, so there may be many opportunities
>> if brackish marshes can exhibit this behavior.
>> We're also considering a trip to a small hydrothermal vent, which could
>> be dramatic... but it seems like it has less similarity to measuring
>> pathologic conditions. Then again, there is not question of H2S so it
>> would be a good demonstration. Welcome thoughts on this as well, would
>> probably head out to the Lassen volcanic area and find a small somewhat
>> isolate hot sulfur hot spring.
listen to....
News & Views on WTUL New Orleans 91.5 FM
Monday, Wednesday, Friday
8am-10am
[[ In the 8am hour = Featured Local Interview
[[ @ 9am = Democracy Now! syndicated
too interesting a conversation to pass up even on a holiday :-)
so i'm interested in triangulation -- like, how can we independently verify
that there is H2S at a test site? I have an electronic H2S sensor connected
to an Arduino, and i recently got a temperature/humidity sensor (since the
H2S sensor is temp/humidity sensitive too) to correct the H2S readings. I
also got a little SD card holder/writer for the Arduino, so I could put
together a little package that records H2S and logs the results, for
comparison with the strips. Then we'd at least have 2 separate readings of
the site. Also:
A. the H2S sensor I have can only detect like 5 ppm minimum (i think, i'll
have to check again) so it's interesting to compare this to either the
strip sensitivity or that of the human nose (0.3ppm, see [1] below) . Or
the max safe exposure level -- say, 15-20ppm see [2] below.
B. though this'd be an interesting comparison and a great way to gain
confidence in the strip technique, we shouldn't take for granted that the
digital sensor is "better" or even particularly authoritative
I may have time on Thursday to try to throw something together and mail it,
unless someone else wants to take a crack at it (i could send the parts
over?)
On Wed, Jul 4, 2012 at 12:10 PM, Scott Eustis <eusta...@gmail.com> wrote:
> Matthew,
> I'm away from my work computer for the day, but off my head hydrogen
> sulfide is generated by certain bacteria in anoxic, reducing conditions in
> wetland soils. it is toxic to plants as well, although wetland plants,
> especially saline marsh plants, can tolerate it. I have much more
> knowledge of plants than of soils and biochemistry, but here it goes.
> Anyone on the list (Adam?) should feel free to correct me, most of my
> knowledge comes from reading papers by Dr. Mendelssohn at LSU, and talking
> to Dr Jenneke Visser at ULL about plants. There's one in particular that
> i can forward later.
> basically, if you have collapsing marshes, that are "waterlogged," the
> soils are likely anoxic and reducing. if you step or stir the soil, and
> gas bubbles up, and it smells like rotten eggs, the collapsed/ing marsh is
> producing some amount of H2S. The amounts generated are very low compared
> to industrial sources.
> many marsh plants have an alternate metabolism for their roots, which are
> often underwater, in low or no oxygen conditions. H2S screws with this
> anaerobic metabolism. Often, sulfide is associated with saltwater, as
> certain ocean salts carry the sulfur. saltmarsh plants are apparently more
> capable of dealing with H2S. So my expectation is that salt marshes will
> produce more H2S under the collapsing condition.
> The site i picked i is not as salty as i would have liked, but I picked it
> because it was one of the closest collapsed marsh sites to a highway. It
> was bare of plants post Katrina, and has received saltwater from Katrina
> and from a flawed management decision--to flood the polder it sits within
> with 12 ppt saltwater from Lake Pontchartrain.
> Shannon was inspired by our trip out to Big Branch, where I demonstrated
> the need for marsh restoration in the area by stepping in the existing
> waterlogged marsh, which bubbled furiously at each step, and stank of
> rotten eggs ( i think i have some video of this on flickr). Bayou Sauvage
> is not as "bubbly" as that site, but it's very accessible and bubbles. I
> think you can see the white foam in some of our photos of Bayou Sauvage.
> The marsh in Bayou Sauvage has already totally collapsed at least once--I
> have this knowledge from trying to re-plant it post-Katrina. the area is
> behind a levee and under pump--this hydrologic alteration has degraded the
> soil conditions. The area is managed for ducks, not plants--and so the
> polder is artificially flooded at times, because the migrating ducks like a
> lot of standing water.
> USFWS and NOSCB had planted bullrushes and *Spartina *grasses there (see
> my 2009 photos)-but they didn't take. *Typha* has naturally colonized the
> area. *Typha *is a plant that is more agnostic of salted and anoxic and
> sulfuric soil conditions and high water variability. Its presence, as well
> as the site's history, indicated to me that this was a good site to try.
> The site was under a drainage regime during our trial--the pumps were on.
> the soil at bayou sauvage bubbles and smells a bit rotten eggy--but not as
> much as Big Branch. it's a 60 min car ride and 45 min canoe into the site
> at Big Branch, which takes at lot more planning.
> if the strips aren't sensitive enough to pick up on the H2S that was
> there--and i'll have to get to my work computer to give you the expected
> numbers, I would try it again at a more brackish and bubbly site. i will
> keep an eye out and ask around.
> perhaps across the bayou from the wetland watchers site out of NORCO. Or
> perhaps fountainbleu park a mile off the boardwalk, or off Hwy 11 on the
> northshore. the trouble with the more brackish, waterlogged sites in LA
> that i am familiar with is that most of the good and screwed up ones
> require a boat (at least a pirogue) to access. The Woodlands Conservancy
> soils definitely stank of rotten eggs, perhaps we can try there, even
> though it's freshwater. That is a former swamp that has been severely
> drained, and the soils have collapsed. The older trees are five feet in
> the air.
> Sara, Shannon, i will make a list of other possible sites to visit and
> assess if we want to repeat this trial in a bubblier, stinkier site.
> scott
> On Wed, Jul 4, 2012 at 2:54 AM, Shannon Dosemagen <
> shannon.dosema...@gmail.com> wrote:
>> Hi Matthew,
>> I'm hoping that Scott will jump in and give you a good description as he
>> gave me an excellent one when I asked a similar question. However, I can
>> point you to papers that he posted on the protocol research note that might
>> be helpful as a starting point:
>> http://publiclaboratory.org/notes/shannon/6-22-2012/h2s-test-experime....
>> I have a couple of research notes I still need to write up from that test
>> as well, I'll try and get those done tonight and will send you links just
>> so you have them as a reference.
>> Best, Shannon
>> On Wed, Jul 4, 2012 at 9:37 AM, Matthew <deepwin...@rhus.winterroot.net>wrote:
>>> I am interested in repeating the H2S measuring procedure as done in
>>> Bayou Savage with some modifications. Hydrothermal vents have been
>>> suggested as point sources, but I've noticed that this experiment takes
>>> place in a marsh. I'm assuming from my reading that this experiment is
>>> measuring H2S produced by anaerobic degradation of plant material by
>>> bacteria. What is a good set of criteria for identifying a wetland that
>>> will produce high amounts of H2S? Can you point me to any papers on this
>>> subject?
>>> I live in the San Francisco bay area, so there may be many opportunities
>>> if brackish marshes can exhibit this behavior.
>>> We're also considering a trip to a small hydrothermal vent, which could
>>> be dramatic... but it seems like it has less similarity to measuring
>>> pathologic conditions. Then again, there is not question of H2S so it
>>> would be a good demonstration. Welcome thoughts on this as well, would
>>> probably head out to the Lassen volcanic area and find a small somewhat
>>> isolate hot sulfur hot spring.
Matthew and I have been chatting in the comments of this post on how to get
one to measure the strip technique against. I.e. if we don't have a way to
verify that there is H2S somewhere, there's no way to correlate a "spike"
in the data with H2S rather than, say, temperature, humidity, some other
gas...
Thanks,
Jeff
On Wed, Jul 4, 2012 at 1:04 PM, Jeffrey Warren <j...@publiclaboratory.org>wrote:
> too interesting a conversation to pass up even on a holiday :-)
> so i'm interested in triangulation -- like, how can we independently
> verify that there is H2S at a test site? I have an electronic H2S sensor
> connected to an Arduino, and i recently got a temperature/humidity sensor
> (since the H2S sensor is temp/humidity sensitive too) to correct the H2S
> readings. I also got a little SD card holder/writer for the Arduino, so I
> could put together a little package that records H2S and logs the results,
> for comparison with the strips. Then we'd at least have 2 separate readings
> of the site. Also:
> A. the H2S sensor I have can only detect like 5 ppm minimum (i think, i'll
> have to check again) so it's interesting to compare this to either the
> strip sensitivity or that of the human nose (0.3ppm, see [1] below) . Or
> the max safe exposure level -- say, 15-20ppm see [2] below.
> B. though this'd be an interesting comparison and a great way to gain
> confidence in the strip technique, we shouldn't take for granted that the
> digital sensor is "better" or even particularly authoritative
> I may have time on Thursday to try to throw something together and mail
> it, unless someone else wants to take a crack at it (i could send the parts
> over?)
> On Wed, Jul 4, 2012 at 12:10 PM, Scott Eustis <eusta...@gmail.com> wrote:
>> Matthew,
>> I'm away from my work computer for the day, but off my head hydrogen
>> sulfide is generated by certain bacteria in anoxic, reducing conditions in
>> wetland soils. it is toxic to plants as well, although wetland plants,
>> especially saline marsh plants, can tolerate it. I have much more
>> knowledge of plants than of soils and biochemistry, but here it goes.
>> Anyone on the list (Adam?) should feel free to correct me, most of my
>> knowledge comes from reading papers by Dr. Mendelssohn at LSU, and talking
>> to Dr Jenneke Visser at ULL about plants. There's one in particular that
>> i can forward later.
>> basically, if you have collapsing marshes, that are "waterlogged," the
>> soils are likely anoxic and reducing. if you step or stir the soil, and
>> gas bubbles up, and it smells like rotten eggs, the collapsed/ing marsh is
>> producing some amount of H2S. The amounts generated are very low compared
>> to industrial sources.
>> many marsh plants have an alternate metabolism for their roots, which are
>> often underwater, in low or no oxygen conditions. H2S screws with this
>> anaerobic metabolism. Often, sulfide is associated with saltwater, as
>> certain ocean salts carry the sulfur. saltmarsh plants are apparently more
>> capable of dealing with H2S. So my expectation is that salt marshes will
>> produce more H2S under the collapsing condition.
>> The site i picked i is not as salty as i would have liked, but I picked
>> it because it was one of the closest collapsed marsh sites to a highway.
>> It was bare of plants post Katrina, and has received saltwater from
>> Katrina and from a flawed management decision--to flood the polder it sits
>> within with 12 ppt saltwater from Lake Pontchartrain.
>> Shannon was inspired by our trip out to Big Branch, where I demonstrated
>> the need for marsh restoration in the area by stepping in the existing
>> waterlogged marsh, which bubbled furiously at each step, and stank of
>> rotten eggs ( i think i have some video of this on flickr). Bayou Sauvage
>> is not as "bubbly" as that site, but it's very accessible and bubbles. I
>> think you can see the white foam in some of our photos of Bayou Sauvage.
>> The marsh in Bayou Sauvage has already totally collapsed at least once--I
>> have this knowledge from trying to re-plant it post-Katrina. the area is
>> behind a levee and under pump--this hydrologic alteration has degraded the
>> soil conditions. The area is managed for ducks, not plants--and so the
>> polder is artificially flooded at times, because the migrating ducks like a
>> lot of standing water.
>> USFWS and NOSCB had planted bullrushes and *Spartina *grasses there (see
>> my 2009 photos)-but they didn't take. *Typha* has naturally colonized
>> the area. *Typha *is a plant that is more agnostic of salted and anoxic
>> and sulfuric soil conditions and high water variability. Its presence, as
>> well as the site's history, indicated to me that this was a good site to
>> try. The site was under a drainage regime during our trial--the pumps were
>> on.
>> the soil at bayou sauvage bubbles and smells a bit rotten eggy--but not
>> as much as Big Branch. it's a 60 min car ride and 45 min canoe into the
>> site at Big Branch, which takes at lot more planning.
>> if the strips aren't sensitive enough to pick up on the H2S that was
>> there--and i'll have to get to my work computer to give you the expected
>> numbers, I would try it again at a more brackish and bubbly site. i will
>> keep an eye out and ask around.
>> perhaps across the bayou from the wetland watchers site out of NORCO. Or
>> perhaps fountainbleu park a mile off the boardwalk, or off Hwy 11 on the
>> northshore. the trouble with the more brackish, waterlogged sites in LA
>> that i am familiar with is that most of the good and screwed up ones
>> require a boat (at least a pirogue) to access. The Woodlands Conservancy
>> soils definitely stank of rotten eggs, perhaps we can try there, even
>> though it's freshwater. That is a former swamp that has been severely
>> drained, and the soils have collapsed. The older trees are five feet in
>> the air.
>> Sara, Shannon, i will make a list of other possible sites to visit and
>> assess if we want to repeat this trial in a bubblier, stinkier site.
>> scott
>> On Wed, Jul 4, 2012 at 2:54 AM, Shannon Dosemagen <
>> shannon.dosema...@gmail.com> wrote:
>>> Hi Matthew,
>>> I'm hoping that Scott will jump in and give you a good description as he
>>> gave me an excellent one when I asked a similar question. However, I can
>>> point you to papers that he posted on the protocol research note that might
>>> be helpful as a starting point:
>>> http://publiclaboratory.org/notes/shannon/6-22-2012/h2s-test-experime....
>>> I have a couple of research notes I still need to write up from that test
>>> as well, I'll try and get those done tonight and will send you links just
>>> so you have them as a reference.
>>> Best, Shannon
>>> On Wed, Jul 4, 2012 at 9:37 AM, Matthew <deepwin...@rhus.winterroot.net>wrote:
>>>> I am interested in repeating the H2S measuring procedure as done in
>>>> Bayou Savage with some modifications. Hydrothermal vents have been
>>>> suggested as point sources, but I've noticed that this experiment takes
>>>> place in a marsh. I'm assuming from my reading that this experiment is
>>>> measuring H2S produced by anaerobic degradation of plant material by
>>>> bacteria. What is a good set of criteria for identifying a wetland that
>>>> will produce high amounts of H2S? Can you point me to any papers on this
>>>> subject?
>>>> I live in the San Francisco bay area, so there may be many
>>>> opportunities if brackish marshes can exhibit this behavior.
>>>> We're also considering a trip to a small hydrothermal vent, which could
>>>> be dramatic... but it seems like it has less similarity to measuring
>>>> pathologic conditions. Then again, there is not question of H2S so it
>>>> would be a good demonstration. Welcome thoughts on this as well, would
>>>> probably head out to the Lassen volcanic area and find a small somewhat
>>>> isolate hot sulfur hot spring.
I can ask the community organizer in New Mexico where he is renting from. I
think its a local solution because they have lots of gas field workers in the
area, so I'm not sure everywhere will have personal alert units like this for
rent.
It would also be interesting to have some kind of continuous digital monitor in
place, as well, but its not totally necessary to calibrate the test strips.
> Matthew and I have been chatting in the comments of this post on how to get
> one to measure the strip technique against. I.e. if we don't have a way to
> verify that there is H2S somewhere, there's no way to correlate a "spike"
> in the data with H2S rather than, say, temperature, humidity, some other
> gas...
> Thanks,
> Jeff
> On Wed, Jul 4, 2012 at 1:04 PM, Jeffrey Warren > <j...@publiclaboratory.org>wrote:
>> too interesting a conversation to pass up even on a holiday :-)
>> so i'm interested in triangulation -- like, how can we independently
>> verify that there is H2S at a test site? I have an electronic H2S sensor
>> connected to an Arduino, and i recently got a temperature/humidity sensor
>> (since the H2S sensor is temp/humidity sensitive too) to correct the H2S
>> readings. I also got a little SD card holder/writer for the Arduino, so I
>> could put together a little package that records H2S and logs the results,
>> for comparison with the strips. Then we'd at least have 2 separate readings
>> of the site. Also:
>> A. the H2S sensor I have can only detect like 5 ppm minimum (i think, i'll
>> have to check again) so it's interesting to compare this to either the
>> strip sensitivity or that of the human nose (0.3ppm, see [1] below) . Or
>> the max safe exposure level -- say, 15-20ppm see [2] below.
>> B. though this'd be an interesting comparison and a great way to gain
>> confidence in the strip technique, we shouldn't take for granted that the
>> digital sensor is "better" or even particularly authoritative
>> I may have time on Thursday to try to throw something together and mail
>> it, unless someone else wants to take a crack at it (i could send the parts
>> over?)
>> On Wed, Jul 4, 2012 at 12:10 PM, Scott Eustis <eusta...@gmail.com> wrote:
>>> Matthew,
>>> I'm away from my work computer for the day, but off my head hydrogen
>>> sulfide is generated by certain bacteria in anoxic, reducing conditions in
>>> wetland soils. it is toxic to plants as well, although wetland plants,
>>> especially saline marsh plants, can tolerate it. I have much more
>>> knowledge of plants than of soils and biochemistry, but here it goes.
>>> Anyone on the list (Adam?) should feel free to correct me, most of my
>>> knowledge comes from reading papers by Dr. Mendelssohn at LSU, and talking
>>> to Dr Jenneke Visser at ULL about plants. There's one in particular that
>>> i can forward later.
>>> basically, if you have collapsing marshes, that are "waterlogged," the
>>> soils are likely anoxic and reducing. if you step or stir the soil, and
>>> gas bubbles up, and it smells like rotten eggs, the collapsed/ing marsh is
>>> producing some amount of H2S. The amounts generated are very low compared
>>> to industrial sources.
>>> many marsh plants have an alternate metabolism for their roots, which are
>>> often underwater, in low or no oxygen conditions. H2S screws with this
>>> anaerobic metabolism. Often, sulfide is associated with saltwater, as
>>> certain ocean salts carry the sulfur. saltmarsh plants are apparently more
>>> capable of dealing with H2S. So my expectation is that salt marshes will
>>> produce more H2S under the collapsing condition.
>>> The site i picked i is not as salty as i would have liked, but I picked
>>> it because it was one of the closest collapsed marsh sites to a highway.
>>> It was bare of plants post Katrina, and has received saltwater from
>>> Katrina and from a flawed management decision--to flood the polder it sits
>>> within with 12 ppt saltwater from Lake Pontchartrain.
>>> Shannon was inspired by our trip out to Big Branch, where I demonstrated
>>> the need for marsh restoration in the area by stepping in the existing
>>> waterlogged marsh, which bubbled furiously at each step, and stank of
>>> rotten eggs ( i think i have some video of this on flickr). Bayou Sauvage
>>> is not as "bubbly" as that site, but it's very accessible and bubbles. I
>>> think you can see the white foam in some of our photos of Bayou Sauvage.
>>> The marsh in Bayou Sauvage has already totally collapsed at least once--I
>>> have this knowledge from trying to re-plant it post-Katrina. the area is
>>> behind a levee and under pump--this hydrologic alteration has degraded the
>>> soil conditions. The area is managed for ducks, not plants--and so the
>>> polder is artificially flooded at times, because the migrating ducks like a
>>> lot of standing water.
>>> USFWS and NOSCB had planted bullrushes and *Spartina *grasses there (see
>>> my 2009 photos)-but they didn't take. *Typha* has naturally colonized
>>> the area. *Typha *is a plant that is more agnostic of salted and anoxic
>>> and sulfuric soil conditions and high water variability. Its presence, as
>>> well as the site's history, indicated to me that this was a good site to
>>> try. The site was under a drainage regime during our trial--the pumps were
>>> on.
>>> the soil at bayou sauvage bubbles and smells a bit rotten eggy--but not
>>> as much as Big Branch. it's a 60 min car ride and 45 min canoe into the
>>> site at Big Branch, which takes at lot more planning.
>>> if the strips aren't sensitive enough to pick up on the H2S that was
>>> there--and i'll have to get to my work computer to give you the expected
>>> numbers, I would try it again at a more brackish and bubbly site. i will
>>> keep an eye out and ask around.
>>> perhaps across the bayou from the wetland watchers site out of NORCO. Or
>>> perhaps fountainbleu park a mile off the boardwalk, or off Hwy 11 on the
>>> northshore. the trouble with the more brackish, waterlogged sites in LA
>>> that i am familiar with is that most of the good and screwed up ones
>>> require a boat (at least a pirogue) to access. The Woodlands Conservancy
>>> soils definitely stank of rotten eggs, perhaps we can try there, even
>>> though it's freshwater. That is a former swamp that has been severely
>>> drained, and the soils have collapsed. The older trees are five feet in
>>> the air.
>>> Sara, Shannon, i will make a list of other possible sites to visit and
>>> assess if we want to repeat this trial in a bubblier, stinkier site.
>>> scott
>>> On Wed, Jul 4, 2012 at 2:54 AM, Shannon Dosemagen <
>>> shannon.dosema...@gmail.com> wrote:
>>>> Hi Matthew,
>>>> I'm hoping that Scott will jump in and give you a good description as he
>>>> gave me an excellent one when I asked a similar question. However, I can
>>>> point you to papers that he posted on the protocol research note >>>> that might
>>>> be helpful as a starting point:
>>>> http://publiclaboratory.org/notes/shannon/6-22-2012/h2s-test-experime....
>>>> I have a couple of research notes I still need to write up from that test
>>>> as well, I'll try and get those done tonight and will send you links just
>>>> so you have them as a reference.
>>>> Best, Shannon
>>>> On Wed, Jul 4, 2012 at 9:37 AM, Matthew >>>> <deepwin...@rhus.winterroot.net>wrote:
>>>>> Hey there,
>>>>> Getting into the swing of the public labs.... I also posted the
>>>>> question below here:
>>>>> http://publiclaboratory.org/notes/eustatic/6-23-2012/h2s-strip-placem... >>>>> as
>>>>> it's not totally clear the best place for discussion of the H2S >>>>> experiment.
>>>>> I am interested in repeating the H2S measuring procedure as done in
>>>>> Bayou Savage with some modifications. Hydrothermal vents have been
>>>>> suggested as point sources, but I've noticed that this experiment takes
>>>>> place in a marsh. I'm assuming from my reading that this experiment is
>>>>> measuring H2S produced by anaerobic degradation of plant material by
>>>>> bacteria. What is a good set of criteria for identifying a wetland that
>>>>> will produce high amounts of H2S? Can you point me to any >>>>> papers on this
>>>>> subject?
>>>>> I live in the San Francisco bay area, so there may be many
>>>>> opportunities if brackish marshes can exhibit this behavior.
>>>>> We're also considering a trip to a small hydrothermal vent, which could
>>>>> be dramatic... but it seems like it has less similarity to measuring
>>>>> pathologic conditions. Then again, there is not question of H2S so it
>>>>> would be a good demonstration. Welcome thoughts on this as well, would
>>>>> probably head out
Just to follow up on which sensor they've been trying in New Mexico, they rented
and pilot tested a Industrial Scientific Gas Badge:
Plus:http://www.indsci.com/GasBadgePlus/
> Matthew and I have been chatting in the comments of this post on how to get
> one to measure the strip technique against. I.e. if we don't have a way to
> verify that there is H2S somewhere, there's no way to correlate a "spike"
> in the data with H2S rather than, say, temperature, humidity, some other
> gas...
> Thanks,
> Jeff
> On Wed, Jul 4, 2012 at 1:04 PM, Jeffrey Warren > <j...@publiclaboratory.org>wrote:
>> too interesting a conversation to pass up even on a holiday :-)
>> so i'm interested in triangulation -- like, how can we independently
>> verify that there is H2S at a test site? I have an electronic H2S sensor
>> connected to an Arduino, and i recently got a temperature/humidity sensor
>> (since the H2S sensor is temp/humidity sensitive too) to correct the H2S
>> readings. I also got a little SD card holder/writer for the Arduino, so I
>> could put together a little package that records H2S and logs the results,
>> for comparison with the strips. Then we'd at least have 2 separate readings
>> of the site. Also:
>> A. the H2S sensor I have can only detect like 5 ppm minimum (i think, i'll
>> have to check again) so it's interesting to compare this to either the
>> strip sensitivity or that of the human nose (0.3ppm, see [1] below) . Or
>> the max safe exposure level -- say, 15-20ppm see [2] below.
>> B. though this'd be an interesting comparison and a great way to gain
>> confidence in the strip technique, we shouldn't take for granted that the
>> digital sensor is "better" or even particularly authoritative
>> I may have time on Thursday to try to throw something together and mail
>> it, unless someone else wants to take a crack at it (i could send the parts
>> over?)
>> On Wed, Jul 4, 2012 at 12:10 PM, Scott Eustis <eusta...@gmail.com> wrote:
>>> Matthew,
>>> I'm away from my work computer for the day, but off my head hydrogen
>>> sulfide is generated by certain bacteria in anoxic, reducing conditions in
>>> wetland soils. it is toxic to plants as well, although wetland plants,
>>> especially saline marsh plants, can tolerate it. I have much more
>>> knowledge of plants than of soils and biochemistry, but here it goes.
>>> Anyone on the list (Adam?) should feel free to correct me, most of my
>>> knowledge comes from reading papers by Dr. Mendelssohn at LSU, and talking
>>> to Dr Jenneke Visser at ULL about plants. There's one in particular that
>>> i can forward later.
>>> basically, if you have collapsing marshes, that are "waterlogged," the
>>> soils are likely anoxic and reducing. if you step or stir the soil, and
>>> gas bubbles up, and it smells like rotten eggs, the collapsed/ing marsh is
>>> producing some amount of H2S. The amounts generated are very low compared
>>> to industrial sources.
>>> many marsh plants have an alternate metabolism for their roots, which are
>>> often underwater, in low or no oxygen conditions. H2S screws with this
>>> anaerobic metabolism. Often, sulfide is associated with saltwater, as
>>> certain ocean salts carry the sulfur. saltmarsh plants are apparently more
>>> capable of dealing with H2S. So my expectation is that salt marshes will
>>> produce more H2S under the collapsing condition.
>>> The site i picked i is not as salty as i would have liked, but I picked
>>> it because it was one of the closest collapsed marsh sites to a highway.
>>> It was bare of plants post Katrina, and has received saltwater from
>>> Katrina and from a flawed management decision--to flood the polder it sits
>>> within with 12 ppt saltwater from Lake Pontchartrain.
>>> Shannon was inspired by our trip out to Big Branch, where I demonstrated
>>> the need for marsh restoration in the area by stepping in the existing
>>> waterlogged marsh, which bubbled furiously at each step, and stank of
>>> rotten eggs ( i think i have some video of this on flickr). Bayou Sauvage
>>> is not as "bubbly" as that site, but it's very accessible and bubbles. I
>>> think you can see the white foam in some of our photos of Bayou Sauvage.
>>> The marsh in Bayou Sauvage has already totally collapsed at least once--I
>>> have this knowledge from trying to re-plant it post-Katrina. the area is
>>> behind a levee and under pump--this hydrologic alteration has degraded the
>>> soil conditions. The area is managed for ducks, not plants--and so the
>>> polder is artificially flooded at times, because the migrating ducks like a
>>> lot of standing water.
>>> USFWS and NOSCB had planted bullrushes and *Spartina *grasses there (see
>>> my 2009 photos)-but they didn't take. *Typha* has naturally colonized
>>> the area. *Typha *is a plant that is more agnostic of salted and anoxic
>>> and sulfuric soil conditions and high water variability. Its presence, as
>>> well as the site's history, indicated to me that this was a good site to
>>> try. The site was under a drainage regime during our trial--the pumps were
>>> on.
>>> the soil at bayou sauvage bubbles and smells a bit rotten eggy--but not
>>> as much as Big Branch. it's a 60 min car ride and 45 min canoe into the
>>> site at Big Branch, which takes at lot more planning.
>>> if the strips aren't sensitive enough to pick up on the H2S that was
>>> there--and i'll have to get to my work computer to give you the expected
>>> numbers, I would try it again at a more brackish and bubbly site. i will
>>> keep an eye out and ask around.
>>> perhaps across the bayou from the wetland watchers site out of NORCO. Or
>>> perhaps fountainbleu park a mile off the boardwalk, or off Hwy 11 on the
>>> northshore. the trouble with the more brackish, waterlogged sites in LA
>>> that i am familiar with is that most of the good and screwed up ones
>>> require a boat (at least a pirogue) to access. The Woodlands Conservancy
>>> soils definitely stank of rotten eggs, perhaps we can try there, even
>>> though it's freshwater. That is a former swamp that has been severely
>>> drained, and the soils have collapsed. The older trees are five feet in
>>> the air.
>>> Sara, Shannon, i will make a list of other possible sites to visit and
>>> assess if we want to repeat this trial in a bubblier, stinkier site.
>>> scott
>>> On Wed, Jul 4, 2012 at 2:54 AM, Shannon Dosemagen <
>>> shannon.dosema...@gmail.com> wrote:
>>>> Hi Matthew,
>>>> I'm hoping that Scott will jump in and give you a good description as he
>>>> gave me an excellent one when I asked a similar question. However, I can
>>>> point you to papers that he posted on the protocol research note >>>> that might
>>>> be helpful as a starting point:
>>>> http://publiclaboratory.org/notes/shannon/6-22-2012/h2s-test-experime....
>>>> I have a couple of research notes I still need to write up from that test
>>>> as well, I'll try and get those done tonight and will send you links just
>>>> so you have them as a reference.
>>>> Best, Shannon
>>>> On Wed, Jul 4, 2012 at 9:37 AM, Matthew >>>> <deepwin...@rhus.winterroot.net>wrote:
>>>>> Hey there,
>>>>> Getting into the swing of the public labs.... I also posted the
>>>>> question below here:
>>>>> http://publiclaboratory.org/notes/eustatic/6-23-2012/h2s-strip-placem... >>>>> as
>>>>> it's not totally clear the best place for discussion of the H2S >>>>> experiment.
>>>>> I am interested in repeating the H2S measuring procedure as done in
>>>>> Bayou Savage with some modifications. Hydrothermal vents have been
>>>>> suggested as point sources, but I've noticed that this experiment takes
>>>>> place in a marsh. I'm assuming from my reading that this experiment is
>>>>> measuring H2S produced by anaerobic degradation of plant material by
>>>>> bacteria. What is a good set of criteria for identifying a wetland that
>>>>> will produce high amounts of H2S? Can you point me to any >>>>> papers on this
>>>>> subject?
>>>>> I live in the San Francisco bay area, so there may be many
>>>>> opportunities if brackish marshes can exhibit this behavior.
>>>>> We're also considering a trip to a small hydrothermal vent, which could
>>>>> be dramatic... but it seems like it has less similarity to measuring
>>>>> pathologic conditions. Then again, there is not question of H2S so it
>>>>> would be a good demonstration. Welcome thoughts on this as well, would
>>>>> probably head out to the Lassen volcanic area and find a small somewhat
>>>>> isolate hot sulfur hot spring.
>>>> -- Post to this group at publiclaboratory@googlegroups.com. To
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>>>> Options at
