I compiled this for my PDCclass and thought people on this list might find it useful.
Any feedback and additions to strategies and resources is always appreciated.
'At last Class, a question was asked about salty soils.
We discussed that there are only a few options for treating salty soils, which are defined as soils haveing a large concentration of soluble mineral salt ions.
1. leave them alone
2. wash them through using water which is less salty (washes salts to another location either downstream or into groundwater aquifers)
3. immobilize and cycle the salts by binding them up in living organisms and on soil organic matter surfaces (increased CEC)
4. Dig out the salt affected soils and remove them -- landfill
my preferred option is usually # 3 and I feel it is valuable to know the options when assessing a site. Salt export from the site can be designed in for example by feeding vegetation to animals which are sold, eaten, etc.or cultivating salt tolerant herbs or crops eaten or sold. Locally adapted species can be found by visiting salt-marshes or other saline areas and observing and identifying species along a salt gradient. These may also be locations for collecting plant materials. After a local list is made, climate analogues can be researched to add to diversity and use potential.
We reviewed the process of salt soil formation: evapo-concentration of minerals which are usually carried in by water (or deposited by settling or applied by humans)
so any long term salt management strategy will include methods that decrease evaporation (which is a primary design strategy in drylands)
Thanks for sharing this. I browsed through and didn't see anything on Quinoa, maybe it would be a good cash crop/calorie crop for saline soils? We need heat tolerant varieties for wider spread adoption though.
"...many varieties can grow in salt concentrations as high as those found in seawater (40 mS cm−1), and four lines have been identified with even higher tolerance."
I'm definitely looking into phytoremediation with some halophytic species (ideally native to Western U.S.)
Questions to All:
If I choose species that are salt-accumulators and then either A) compost them and spread it back out or B) use them as animal forage
how does this affect the nutrient cycle of minerals in the salt?
I read one academic report that had success with this and thought acidic compounds had a chelating affect on the Na+ ions and was able to separate the other various metals and thus making them available to microbes to then feed the plants. This increased the biomass of a variety of (rice?) they were measuring.
Should I leach water through the compost and risk losing the humus and other nutrients?
What happens when they are ingested by a ruminant? Does it just come out in their manure and go right back to the surface or get broken down by the anaerobic organisms in their tummy?
Thanks any suggestions on other ways to gather the accumulated salts would help too!
The University of Texas has done some studies and remediations here in West Texas on oil drilling sites, don't know the complete list of plants but I do know that Four Wing Saltbush and Kochia were used extensively and were top rated by the livestock and wildlife in the area.
Just the other day, I was thinking ... about this tiny ad:
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