SALT: Convos from the Gardens Master course

Gardens Master Course was awesome. I was virtually attending. lots of kudos to everyone that made that happen. The chat was great.

There were at least two folks, one in virtual chat and one there in real life , and perhaps another, talking about Salts in the soil and perhaps sub soil infiltration from adjacent properties, via upstream irrigation, raising the water table and creating a potential problem. Oh, and one other person talking about Selenium issues. I've got some stories on Se.

I'm currently in north Idaho, but in a former capacity I've had my stint around extreme salty soils and salty water tables. I'm talking 15,000+ electrical conductivity (EC) at uS/cm (micro Siemens/cm), (15 dS/cm (deci Siemens/cm) (?)) Ocean water is 50 dS/cm and tap water is (should be) 0.5 dS/cm max . I've done plenty of water sampling for EC (and a host of other things) and my M.S. was soil salinity mapping using electro magnetic induction, and looking at micro-topography and its influences on plant production.  

Did I mention I'm a soil scientist, botanist, ecologist, default hydrologist, and pseudo environmental engineer...That has been interested in permie stuff since before I knew what permaculture was... back then (20 years ago), it was awesome Profs and agroforestry. Long story.

There's also an interesting note to be added that EC is an electrical conductivity measurement and that this does not necessarily represent the total dissolved solubles (TDS).  TDS is very important in figuring out. Note, figure out your TDS and then you can generally asses the TDS based of EC measurements.  And pH can also be a help to determine various things... like alkaline, sodic, and various nutrient and mineral availability and potential toxicities.

I have plenty of stories. Lets Rock this Convo!!!

I'll start with this story (below), and with my name in this post, will pretty much say where I worked without saying where I worked...and my schooling which will be obvious to anyone who looks into my background.

The central valley of California, middle of San Joaquin Valley (SJV), zone 9, 12 inches of annual rain, but built between the coastal range (large part marine origin) and the batholith of granite in the Sierras. Millennia of oceanic build up, up lifting, salt and obscure mineral concentrations (to include Selenium, Mercury, Gypsum type Asbestos) .

Roughly 500 years ago, Spaniards found San Francisco Bay and looked into the "interior" (from Mt. Diablo) of California and thought it to be "an extension of the sea". For at that time, the central valley was a massive complex of flooded plains. As time went on, the lands got drained, rivers re-routed, irrigation systems installed, and the entire landscape changed. However, there was a large portion of the valley that was never able to be converted to farm land. The most notable reason being, the salty ground water table was so shallow that the water "perked" up to the surface and any attempt to use fresh water from the Sierras to irrigate these lands just brought the salt water to the surface and into the root zones of any plants that were intended to be crops. Thus, the reason for the huge swath of wetlands that still exist in Cal. These lands could not be controlled by man, so they remained as wetlands, and now, help to aid in a vital network of critical lands to support the Pacific Fly Way.

Inter-calary chapter: you know redwood type species used to run from Cal coast to Wyoming? Yup! Before the sierra nevada batholith showed up. I've heard stories of people cutting wells into the SJV and well diggers bringing up redwood 500ft+ below the surface.

There were however many attempts to convert some of these lands. The biggest "revolution" was tile drainage. Basically say a 10" perforated pipe buried about 6ft down to pull off shallow ground water (GW) and move it to somewhere else. This did help to "reclaim" some lands but there were some significant problems that ensued. During the 1970's, the guvment thought it was a good idea to take all this tile drained water to the SF bay. Well that project failed, and they decided to create a massive holding pond, i.e. evaporation pond. This was also at the time post vietnam where the chemical production companies needed to use (sell) agent orange and other chemicals somewhere else. Cotton fields. Long story, but Selenium got blamed and 10's of thousands of acres of private lands got seized by the guvment. I've got lots of stories there. Kesterson. got buried in 10ft of clay and essentially a "no-go zone". again, long story.

Back to Point. SALT. there are lots of potentials on how to deal with salt on your land. You could tile drain. But, what I have noticed in the wetland complexes, Organic Matter!!!  swales, cattails, tule, huge amounts of fast producing salt tolerant species. Bring in lots of chipped material, put them in the swales, OM, OM, OM. OMG.

Those that have Salt problems, send me a note, or respond to this post.

Inter-calary chapter: I have a story on someone that had a super salty perennial stream running though their property, so they planted a bunch of halophytes... they dried up the stream. Think about ET (evapo transpiration)... quadrupled it and the halophytes accumulated the salts on the leaves. So then think about wanting to compost all those plants with salt accumulation. (?)

Geoff Lawton had some enormous victories in his adventure in Jordan regarding salt reclamation. And I've seen some stuff in similar circumstances albeit, nothing along the lines of what he created.

At some point, I probably should write a published article of my shenanigans, eh. some time.
Let's Start this Convo about SALT!

P.

Think about ET (evapo transpiration)... quadrupled it and the halophytes accumulated the salts on the leaves. So then think about wanting to compost all those plants with salt accumulation.

Thanks for starting this conversation Patrick. What do you suggest we do with the salty leaves and debris from halophytes? Saltbush is the main native plant on the wild land around here. The small dried leaves cover the ground and form a web of salt mulch. Out of this grows more saltbush. I use some of the debris and ash in adobe blocks for building. Any other ideas for eliminating the salts once the plants take them in?

Amy Gardener wrote:

Think about ET (evapo transpiration)... quadrupled it and the halophytes accumulated the salts on the leaves. So then think about wanting to compost all those plants with salt accumulation.

Thanks for starting this conversation Patrick. What do you suggest we do with the salty leaves and debris from halophytes? Saltbush is the main native plant on the wild land around here. The small dried leaves cover the ground and form a web of salt mulch. Out of this grows more saltbush. I use some of the debris and ash in adobe blocks for building. Any other ideas for eliminating the salts once the plants take them in?

Short answer: it depends.
I see you're in NM, never been there. I'm guessing "saltbush" is an Atriplex (?).
Here's the questions you have to ask yourself outside of your thought of "eliminating the salts", because frankly, elimination of the salts is never going to happen. There are ways to "tie" them up, but here's the questions.
-  what are you trying to achieve?
- how many acres are we working with?
- do you have shallow ground water?
- what are your soils down like to 6 ft? chemical analysis? etc...?
- are you monsoonal?... large amounts of rain very fast? flood area?
- do you have any concerns about heavy metals (cadmium, uranium, others?)
I'm sure you can think of other questions, but there's a start and these can help you decide what to do with what you've got and how to manage. Which will eventually help you decide how to proceed.
Without known details, I apologize, I'm not going to even ponder on what I would do. These are tricky circumstances, and I don't want to lead you on a wrong path.
Regards.
P.
edit:feel free to send me an email, or just carry on in the forum... ;) perhaps thinking though this process might help others. Cheers!

...one of my photos... salt marbling.

The situation in New Mexico certainly is complex. Luckily, Texas A&M provides a helpful resource that explains how to manage salt-affect soils by "Improving drainage, leaching, reducing evaporation, applying chemical treatments, [and] using combination of these methods."
https://cdn-ext.agnet.tamu.edu/wp-content/uploads/2018/10/E60-managing-soil-salinity.pdf
Regarding the original question about saltbush (any of the ~250 Atriplex species) I'll continue to manage the salt-laden plant matter by incorporating the residues in adobe structures.

Here’s a few papers... They include my work.
https://www.academia.edu/24476625/Wetland_response_to_modified_hydrology_with_respect_to_salinity_management_biological_monitoring?email_work_card=view-paper

https://www.academia.edu/24476569/Use_of_environmental_sensors_and_sensor_networks_to_develop_water_and_salinity_budgets_for_seasonal_wetland_real_time_water_quality_management?email_work_card=title

https://www.academia.edu/24476624/Adaptive_coordinated_real_time_management_of_wetland_drainage?email_work_card=title

I’ve got lots of stories. If you want to use chemical treatments to deal with salts, eh, do what you want. I’m pretty sure there’s better options. Monitoring , tmdls, testing is one thing but figuring out your systems and figuring out how to deal with it is a completely different circumstance  

I actually planted Atriplex Halimus in my polytunnel and it's growing quite well (the one's outside didn't survive my wet winter, even on my well drained south facing drivebank). The leaves make quite a tasty snack - I've not got enough to make a meal from yet, but both my surviving bushes are doing quite well.

I don't think i've a problem with salt in the soil - although we do get salt laden rain from the sea spray sometimes. We're about a mile and a half from the sea over the hill, but in stormy weather it sometimes tastes a bit like tears on my face! I'm pretty sure that our ample rain washes out any salt fairly well. Is this something I can check out?

Hello Patrick, I have recently been enamored by the Gulf of California and what appears to be an ancient inand sea running northwards to the Salton sea. Several topics of interest are included in this.
Recently the Govornor of Arizona announced a project to build a desalination plant on the eastern shore of the gulf and pipe water to Phoenix.
I also stumbled across a project where folks are reestablishing the estuary and mangroves along the eastern shore.
So it seems that this area is ripe for permaculture practices to include aquaponics , sea farming , and water harvesting.
One of the questions that I am trying to find an answer for is if the gulf, and any inland ,salt water sea, contrubutes to the underground aquifers ?
Does the plant life,  land, and beaches act as any sort of filter?
Thanks, Miles

I'm going to have to break this down.

Miles Flansburg wrote:Hello Patrick, I have recently been enamored by the Gulf of California and what appears to be an ancient inand sea running northwards to the Salton sea. Several topics of interest are included in this.

To Start, do you know the Salton Sea is a product of an accident? Yeah, (I'm going off memory here without referencing, so bear with me). I think it was around 1910, a pipeline from the colorado river headed to Los Angelas (LA) broke and flooded an area that was an ancient terminal lake.  Salton Sea was apparently quite nice when it was first "created". You can find in web search all sorts of brochures as an "inland oasis" from the 1920's. Indio Valley and the Ag down there is intensive and not kind to the environment. Lots of nasty ag tail water that drain directly to the "sea" to include all the chemicals. It is far enough from the Gulf of Cal that I don't think it puts pressure on the GW, but, it likely does.  I suppose the bigger issue is the fact that the Colorado river in most years runs dry before it even hits the Gulf of Cal. I would assume that there is a bunch of tail water that makes it to the Gulf of Cal, likely surficially, adding to the eutrophication issues they have.

Here's one of the biggest issues of ancient terminal lake beds. HEAVY METALS. All sorts of nasty stuff, (and then add chem ag waste(tail water) on top of that).  This is a long topic on bio-geo-chemistry, ...especially when mixed with various nutrients (who knows what the agro chemicals do!?!)...

Quick story, some metals, let's say cadmium, are stable in certain circumstances, and relatively inert. Lets then add a bunch of nitrogen to that. game changes. all the sudden you have a situation of a huge toxic affect and all the sudden the ground water is contaminated with cadmium ( no specific sources that I will reference, but look into the San Joaquin Valley, Cadmium and Dairies). Mercury is another example. Methylization is a process that I won't get into (a paper I never finished :), but the type of mercury can be significant to the absorption of plants or animals or humans. Selinium, boron, ... list can go on.

Here's another story, around the same time LADWP (Los Angelas Department of Water and Power) was building pipelines from the colorado, they were doing the same from "The Long Valley" (eastern Sierra's and white Mountians)... Owen's Valley to Mono Lake. Well, they dried up Owens Lake (by water diversions), and nearly dried up Mono Lake (similar), they would have gone further north to bridgeport, if it wern't for "save Mono Lake" activists. Owens lake is still "dry" but there were problems with all the heavy metals from the now dry lake basin and "dust" getting blown into the air and causing huge health issues. LADWP's "remediation" was to put sprinklers out to "keep the dust down".

Inter-calary chapter: in the 1910's a bunch of people from LA bought up a huge amount of land in the Bishop area (short version), then donated it to LADWP with all water rights, thus, after pipelines, transferring the water  to LA, and then development.  I think "Cadilac Desert" did a good summary of the fiascos. Also, If anyone has not seen "China Town" (Jack Nicholson 1970's) it's a must. ...the purposeful causation of massive droughts, threatening and bulling people off the land to get water rights for development and "progress". I'm going off on a tangent. But there is more to that story.

Miles Flansburg wrote:Recently the Govornor of Arizona announced a project to build a desalination plant on the eastern shore of the gulf and pipe water to Phoenix.

This is an interesting topic. However. what do you do the salt that is removed? Where does one relocate the salts extracted? Are the salts toxic, metals? Where is the energy coming from to do the desal? The filters? As I recall, I think phoenix was once a huge wetland complex (?) and now the water table is at 500ft below surface(?). unfortunately not sustainable and this seems like an effort of grasping at straws.

Miles Flansburg wrote:I also stumbled across a project where folks are reestablishing the estuary and mangroves along the eastern shore.

I like this topic. Do let us know if you come across any interesting articles expanding on this!!!

Miles Flansburg wrote:So it seems that this area is ripe for permaculture practices to include aquaponics , sea farming , and water harvesting.

Lots of potentials here. But, as I mentioned above, the Colorado River barely makes it to the Gulf of CAL in a good water year. and even then it's just a cess pool of crud from 4 states of chem ag (?).  There are a lot of tiny shrimp and talapia that are farmed from that area. Now, on a small scale (I'm thinking out of the box, and with probably plastic (evil word) some solar distillation and potentially some bio remediation with fast growing plants. Note, most the bio remediation plants for toxics need to be removed off site and incinerated.  just a short thought, open for discussion.

Miles Flansburg wrote:One of the questions that I am trying to find an answer for is if the gulf, and any inland ,salt water sea, contrubutes to the underground aquifers ?

yup. above, I'm getting tired (haha not of this convo, but because its late here in Pac Time ;)
EDIT: this is an interesting topic. I've had profs and attended conferences of engineers looking into this specific circumstance, I won't go into details on who, but, the balance of GW extraction rate verses salt water intrusion is well know and studied and various models have been put out to calculate rate of inflow vs outflow. Heck, I even had a colleague putting an inert nucluear tracer into the head waters of Yosemite to figure out residence time and and transport of the water. Rodamine is another "inert" tracer".  Lots of studies there, (merced, SJV river, LA group of folks.). I have a lot of stories and a lot reading under my belt. It is hard to know when to stop. send a note.

Miles Flansburg wrote:Does the plant life,  land, and beaches act as any sort of filter?
Thanks, Miles

Potentially! HAHA, Mate, IT DEPENDS. all things are possible, it's depends on the specific circumstances of a specific site. Yeah, I can give generalities as I've worked with and helped set up plans for basin wide 100,000s acres approach to deal with "situations", but that doesn't help one with their small holding.

Here's the take home message. *Learn your environment. *Learn your local geology. *Learn your soils. *Learn your networks of water movement. *Learn how all of this affects you at your local level. *Learn your plants. *Learn your local politics! And Organic Matter, Organic Matter, Organic Matter!
Edit: I'll be happy to give personal consultation.
Hope this tiny note finds you all well.
Cheers.
Patrick

Thanks Patrick !  HERE is the project I was talking about in the gulf. Looks interesting and I hope they are successful.
So sea water does contribute to underground aquifers? Does the salt get into the aquifer or is the water purified as it moves through the soil?
I mentioned the Salton Sea as it appears that that area is at or below sea level all the way to the gulf and it seems that water from the gulf could be moved easily through that whole area. Then a project like that linked above could turn the desert green. With possible fisheries , and recreational communities being founded.

Amy Gardener wrote: The small dried leaves cover the ground and form a web of salt mulch. Out of this grows more saltbush. I use some of the debris and ash in adobe blocks for building. Any other ideas for eliminating the salts once the plants take them in?

Amy Gardener wrote: I'll continue to manage the salt-laden plant matter by incorporating the residues in adobe structures.

I had a thought... if you have Sodic soils, pH above roughly 8.5, you might have sodium issues (Na).  Or if the plant material your adding to the bricks is high in sodium salts you could have issues. Excess sodium can cause your clay to defloculate which could cause brick failure.
I’ve seen soils that were 60% clay but would not make a soil ribbon because of the sodium content... sodic soils basically just turn to liquid when wetted
Something To check

Miles Flansburg wrote:Thanks Patrick !  HERE is the project I was talking about in the gulf. Looks interesting and I hope they are successful.

This is awesome! I'd love to see how there projects work out. They've got to have some big $$$ backings and guvment support (grants) to be pulling off some of those project in uganda and namibia ... The gulf of Cal one is muy bueno!

Miles Flansburg wrote: So sea water does contribute to underground aquifers? Does the salt get into the aquifer or is the water purified as it moves through the soil?

Short answer, Yes, it can. but, it depends. My personal experience/knowledge on this topic is limited to Cal: Humboldt bay, SF Bay Delta region and inland rivers and tributaries, and a little down in LA basin. Think of it as a halocline (not quite the right word, but it will suffice): a boundary between fresh water and salt water. So, basically pressures between inflow and out flow creates a somewhat horizontal line between fresh water and salt water. Think of it in this circumstance; you have fresh water coming into a system and the salt water pushing against that freshwater. You can only pull so much freshwater before you start pulling the salt water into the well ( or surficial diversions) before you get salt water intrusions. There's lots of models on this. On a smaller scale (in my studies, another paper never written), in a large channel ((max ~500cfs) surface flows for irrigation) in San Joaquin Valley, I figured out a threshold of the amount of freshwater in CFS needed to keep the shallow salty ground water from intruding into the canal; i.e. there was a certain level of fresh water flow needed to keep the salt water table "at bay". I really ought to write that paper. Bottom line, Yes, but it's a balance. in flow -vs- out flow. Hmm... this is a semester course and a half... I'm going to stop here. with luv.

Soil filtering. there's only so much soil can do and soil is only (as NRCS defines) to 6ft from surface. There are some rocks and stuff deep down that can filter or slow salt intrusion, but you put negative pressure on one side, and unless you have an impervious barrier, things are going to move.

Miles Flansburg wrote: I mentioned the Salton Sea as it appears that that area is at or below sea level all the way to the gulf and it seems that water from the gulf could be moved easily through that whole area. Then a project like that linked above could turn the desert green. With possible fisheries , and recreational communities being founded.

Considering the Salton Sea area was a dry baron wasteland prior to the accidental flooding, I highly doubt there was any gulf water intrusions. Not to say there isn't some deep geologic influences. But, considering it is an area of highly productive lands, I'm guessing, historically, that was once an area that the Colorado River flowed upon depositing huge amounts of silt and clay.

I find it interesting that most folks think in 10s of years or even hundreds of years. But think about 100s of thousands of years. Our landscapes and the environment of these landscapes have changed so dramatically even over the past 10,000 years. It's all so interesting and makes one ponder on what once was and what will be!?!
Cheers
P.