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  • (Dr. Jaradat) We live in a world of salt, but we do not recognize it.

  • (Dr. Cihacek) Once it's salinated, you got a problem.

  • (Dr. Hopkins) One of the points that many, many farmers have said is

  • that they're seeing salts in places

  • that they'd never witnessed problems before.

  • (Harold Steppuhn) If I'm a producer and on my ground,

  • I've got a problem with it-- it's not overblown--

  • that's my livelihood off that land.

  • Funding for "Salt of the Earth"

  • is made possible by an EPA Section 319 grant

  • administered by the North Dakota Department of Health.

  • the Eastern North Dakota

  • Resource Conservation and Development Councils,

  • with support provided by the...

  • ...helping people help the land,

  • and by the members of Prairie Public.

  • It's a waste of fertilizer, seed,

  • and your time and effort on it.

  • It went from, I would say 5% to 10% of the farm acres

  • being affected by salinity to up to 40% to 50%.

  • Salinity isn't a new problem, it's a worldwide problem

  • (Matt Olien, narrator) If you've driven by farm fields in the Upper Great Plains,

  • you've no doubt noticed patches of white,

  • chalky soil, usually near roads and ditches,

  • that just doesn't seem to belong,

  • and doesn't seem to go away.

  • Farmers wish it would.

  • It's soil salinity, too much salt in the soil,

  • and it can prove nearly impossible

  • to grow a productive crop in those areas.

  • Overall reduced soil health, so compaction issues,

  • reduced biological activity.

  • You don't have as good of soil to till.

  • It's harder to work the soil.

  • A lot of that depends on your strategies

  • you're using for management-- if you're using

  • conventional tillage or no till or strip till.

  • But it really depends on the producer

  • and what they're willing to try.

  • In my area I would say

  • over 95% of my fields have salinity,

  • and 80% of them have visible white spots

  • that are well in excess of this.

  • All of my producers are very concerned about it

  • and are actively looking for answers and trying new things

  • and trying to seed some cover crops,

  • trying some crop rotations, trying some limited drainage

  • when they can get the permission.

  • So the producer is going to try to pick the crop

  • that gives him the best option and economic return.

  • (narrator) Excess Salinity is caused generally

  • by too wet of conditions resulting in a high water table.

  • Most agree the problem in the Upper Great Plains

  • got worse around 1993

  • when the dry cycle converted to a wet cycle and has never left.

  • But the problem has been around for centuries.

  • (Dr. Jaradat) The land in Mesopotamia is very flat,

  • and irrigating that land created problems

  • in addition to the high temperature

  • and high evaporation from the irrigated water.

  • Salts became concentrated, and the irrigation water

  • coming from the twin rivers, the Tigris and Euphrates,

  • enriched that salt in the Mesopotamia plain,

  • and in less than 1500 years,

  • the problems started showing up

  • to the point that most fertile parts

  • of lower Mesopotamia turned into white crusts.

  • People went hungry, and cities

  • and the empires themselves crumbled

  • because of the loss of their wealth.

  • (Dr. Cihacek) This is a geologic process

  • so it's been going on for a long period of time.

  • We've got relatively young glacial soil.

  • A lot of our soils were pushed in here by the glaciers,

  • spread out on the landscape.

  • So as these salts weather-- they're young materials;

  • there's a lot of things to weather in there.

  • They dissolve and go into the water.

  • Then wherever the water goes, they carry these salt minerals.

  • (Dr. Abdullah) Although it is a problem here,

  • but it's no comparison

  • to the salinity problem in other parts of the world.

  • Just to give you an example-- California,

  • the Joaquin Valley and the Salton Sea.

  • The problems there are much bigger.

  • The world is losing approximately

  • a million hectares a year to salinity,

  • and there are 200 million hectares of saline land

  • which is not producing up to its productive capacity.

  • There are issues in the Nile Delta

  • especially after the construction of the Aswan Dam.

  • After the construction of the dam,

  • this kind of natural remedy, so to speak,

  • of soil fertility and handling salinity stopped abruptly.

  • Based on that, in fact, major health problems were created.

  • (narrator) In our region, the topography of the land

  • has lent itself to salinity problems,

  • forcing many farmers to move this land

  • to the Conservation Reserve Program.

  • When the glaciers came through here,

  • they ground up to pure shale,

  • and most of the salinity that is in our soil

  • originated from the pure shale formation

  • in Eastern North Dakota at least.

  • We were just looking in our training yesterday

  • at a soil survey that was completed

  • in Stutsman County back in the '80's

  • before the wet cycle really started.

  • There was only, I think, about 10 acres

  • of a whole quarter section that was mapped saline.

  • I believe that there's no question

  • but that some of the salinity that we're seeing

  • and the degree and the nature of the salinity,

  • it's a function of what we're doing with water.

  • It's linked to the Red River Valley floods.

  • It's linked to overland flow.

  • So consequently what that means is,

  • is that there's simply more water on the landscape.

  • More water either runs off the landscape.

  • More water resides within the landscape, and there's

  • less water that is moved back up through evapotranspiration.

  • It's roughly 10.8

  • deciSiemens per meter.

  • And in this type of sampling,

  • it'll show less salts 'cause we have

  • a higher concentration of water with this soil, but that would

  • easily equate to 25 deciSiemens on the other methods,

  • and that is restrictive to almost all plant growth.

  • (narrator) Salinity can be invisible or visible.

  • Either way, it is affecting the bottom line and livelihood

  • of producers all over the Upper Great Plains.

  • Joleen Hadrich with North Dakota State University

  • has researched the economic impact of salinity.

  • What we know is that their yield is going to decrease,

  • and that, of course, is going to relate

  • into lower revenues and a lower profit level.

  • Slightly saline would result in about a 15% yield loss.

  • The moderate would be 50% yield loss.

  • When I applied the average crop prices

  • that we're receiving right now in those yield decreases,

  • it resulted in $150 million decrease in revenue.

  • (Bill Schuh) I think it's first and foremost a crop problem

  • and secondly an economic problem.

  • The loss of crop yields from salinization of the soil

  • is a very, very major economic loss for our state.

  • (Joe Breker) I did a recent poll

  • with our group, our corn growers group, and it was

  • fairly common to have producers from all over the state

  • that are in the corn growers that had from 10% to 15%

  • of their farms severely impacted by salinity.

  • In terms of an overall problem, we could say

  • that the agricultural land in Canada,

  • about 1/3 includes salt-affected soils.

  • If I'm a producer, I will try to minimize that--

  • any kind of problems that relate to salinity--

  • primarily because my assessed lands,

  • the assessments, will decrease

  • if my lands are identified as salinized.

  • When we get to an EC of about 8 which is moderately saline,

  • we have at least 50% reduction in yields on wheat.

  • You can have 75% yield loss on corn,

  • and soybeans, you might as well forget it

  • because we're down to maybe 10% or not even worth harvesting.

  • Basically it's an osmotic problem.

  • If you get too much salt on the outside,

  • you have too much osmotic suction on the outside,

  • it competes with the electrolyte in the plant,

  • and the plant reaches a point

  • where it can't imbibe water properly,

  • and you start getting yield reductions.

  • (narrator) Another fear is what has happened

  • in other parts of the world.--

  • health issues, food supply issues and water quality issues.

  • We constantly review the best available science from EPA

  • and their contractors that they work with--universities

  • that develop the best toxicological information

  • that's available to date, and we incorporate those.

  • If it's something immediate, we do it right away

  • in our water quality standard.

  • (Bill Schuh) I don't think that on the basis

  • of current EPA and CDC documents we can conclude

  • that sulphate is particularly damaging to water quality.

  • As far as drinking water quality is concerned,

  • people drink water that have a lot of salts in them.

  • There's a very wide range of qualities in the waters

  • that people drink and are capable of drinking.

  • Right here in this area of the field--this is one of

  • the more obvious places that you'll see salt.

  • The obvious effects of the salt is this white crusting.

  • I see too many guys trying to manage their salinity.

  • They put some into CRP, but they don't go far enough,

  • and then that salinity just continues to move out,

  • and then they're mad because they don't have an impact,

  • and it's just making it worse and worse.

  • (narrator) And as you'll see next, the solutions farmers come up with

  • can mean the difference

  • between lost revenue and successful yields.

  • Good management practices for salinity would include

  • definitely CRP, understanding that,

  • the variable rate and site specific technologies

  • is the biggest one that I'm involved with.

  • (David Burkland) Actually in Grand Forks County here,

  • the level of salinity is

  • one of the higher levels in the Red River Valley

  • so we've tried a lot of different things.

  • We have put some land into CRP,

  • but we've done other things too

  • to try to overcome the saline conditions--just crop choice

  • is a big factor, picking the right crops.

  • Picking crops that are tolerant to saline conditions

  • is real important.

  • (Shawn Kasprick) On the precision ag side of things,

  • we got different site-specific products

  • and services that we can provide that will give the growers

  • a handle on where their salinity is,

  • what impact it has on their crop, and how far out

  • that impact really is effecting their crop.

  • That all will wrap up eventually

  • into a variable rate application for fertility

  • and eventually the grower's bottom line.

  • (Joe Michels) It takes a little while to get established.

  • It did the job for me.

  • We have had salinity issues.

  • There's one hayfield we got from a fella that got sick.

  • He told the landlord that he

  • wanted to rent it to my dad

  • back in the early 70's.

  • We took it over; the ground was white.

  • It would grow foxtail, kochia, and not too good at that.

  • Then the garrison seemed to help.

  • It took a long time to establish, but it is very thick.

  • We got a good root structure

  • where Dad could drive across there with a swather

  • in the water and not get stuck.

  • (Dr. Cihacek) Cover crops, especially deep-rooted cover crops,

  • can have an effect on lowering the water table in an area.

  • My favorite crop to lower water tables is alfalfa

  • which is a perennial, permanent cover type crop.

  • Alfalfa is very, very deep-rooted.

  • (Hal Weiser) Out in Montana, they've really had a lot of success

  • in addressing saline seeps

  • and addressing how to correct those situations.

  • One thing that's happened- there's been a shift

  • in the western part of the state to no till

  • so they've gotten a lot more efficient at water.

  • A couple of years ago in 2008,

  • we did a special initiative through the Equip Program

  • which allowed us to provide cost share

  • to producers that were having issues with salinity,

  • and that was specifically on saline seeps.

  • What they wanna see is which direction the groundwater

  • is flowing when they start testing this,

  • and then they wanna see the levels of the water.

  • And as the water goes down, that means the salts are going down.

  • The soil on the surface is more productive

  • as the salts go lower into the soil profile.

  • I can't honestly say what that piece of ground looked like before,

  • but I was out on it last year on our crop tour,

  • and like he said, you don't have the boggy areas out there.

  • We drove across that with vehicles with a school bus.

  • There's good ground cover, and it's actually very productive.

  • (Joe Michels) We are able to seed everything.

  • If you get something growing out there,

  • use up the water, try to push the salts down.

  • [motor purrs]

  • (Paul Overby) So this is the obvious saline area

  • where we've got the while soil,

  • and nothing is growing except kochia.

  • So we get back to almost the same spot every year

  • so we've not skewing our results

  • by testing one spot one year and then two years later

  • coming back and doing something that's better.

  • We're probing the same area.

  • We've done that consistently now for four years.

  • (Paul Overby) The reality is, the water tables all over

  • the Devils Lake Basin are full to the point of discharging.

  • We've had years in this area

  • where I got stuck on the side of a hill.

  • What we started doing was actually developing

  • zone management for our fields.

  • That idea intrigued me, of being able to apply

  • the right amount of nutrient in the right parts of your field

  • to match the crop yield potential.

  • We actually use our experience then to tell the story

  • as we go out and do seminars and meet with farmers.

  • And a lot of farmers are a little surprised just like I was

  • that the saline issue was much bigger than what they see.

  • Almost every farmer says well, I turn my fertilizer off

  • when I go through those white areas.

  • I don't fertilize those areas; I know not to do that.

  • But they don't realize how far away the saline issue really is.

  • And so when we create maps for those farmers

  • and then delineate that out, that makes sense to them.

  • Then we started the business

  • of making those maps for other people,

  • training people how to use them,

  • doing seminars for people and pointing this out.

  • This is part of the management.

  • I think the first solution is (1) recognizing the problem,

  • and then (2) keeping after it.

  • It isn't ever gonna go away.

  • Water moves up and down in the fields.

  • We've been doing some work on this probably going into

  • our 3rd year now, and certainly when salinity is really high,

  • then we get very low, almost no yield in potatoes.

  • Especially since 2005, we had a lot of rain in our area here,

  • I know just across the line they had some similar difficulties,

  • definitely brought more saline to the surface, and since then

  • we've had a little bit more

  • quality problem with our potatoes.

  • There's really nothing that physically,

  • chemically I should say, removes salts.

  • You're not gonna change the composition of that.

  • You have to either physically either drain the salts away

  • or put in a crop that can tolerate

  • the elevated levels of salt in the soil.

  • Late '90's, we chose to put

  • a lot of our most severely saline land into CRP.

  • That was a good option.

  • I mean, that was an excellent option for us.

  • So we put a lot of that land into CRP,

  • and they used tall wheat grass, for example.

  • We've always tried to keep crop rotations.

  • Winter cereals are good because they will generally grow

  • on saline ground better than row crop like corn or soybeans.

  • But you have to grow what makes money,

  • and not that winter wheat isn't good,

  • but you can't raise winter wheat every year or you can't raise

  • sunflowers every year so you have to raise a rotation,

  • and some of those rotations aren't always very salt tolerant.

  • (Rick Burgum) Well, the best way to reduce your salinity problem

  • is to drain the surface water.

  • Oftentimes you can't do that.

  • The passive ways to do it are to grow something,

  • but you have this contradiction 'cause nothing grows.

  • The best thing to do is to grow your way out of it,

  • and we gotta find crops that will grow,

  • and then we've got to be able to practically grow them.

  • What we've doing on this plot is trying to show differences

  • in management, things that we can do to help assist

  • salt mobility and try to get crop production and growth.

  • With this research here, we're trying to show that tillage is

  • not an effective management tool for saline areas and salt areas,

  • specifically when they have a lot of sodium

  • but also when they have a lot of calcium.

  • In these plots, we did some tillage, we did some no till,

  • we also did some no till with straw cover to reduce evaporation.

  • I really have 3 basic treatments.

  • I have high evaporation,

  • what we would call a normal evaporation here

  • with our no till, and then also reduced evaporation.

  • And what the evaporation does is bring the salts to the surface.

  • So we're actually increasing the salts in the concentration

  • at the surface with the tillage and the no till.

  • The only treatments that are helping us to reduce it

  • a little bit is with the straw.

  • I think the drainage is a big thing

  • to get rid of the excess water first,

  • and that'll help probably pull away from--

  • it'll start to shrink some of these ponds,

  • and that way the salts will start disappearing on their own.

  • We've been in kind of a wet cycle

  • so that's probably part of the problem too.

  • From here to there the salinity was twice as much on this plot

  • as it was there, so within ten feet we had double the salinity.

  • Even though there's not a lot of topography change,

  • there's no soil type change, it's a water mobility thing.

  • We have downward movement of water right here.

  • With the resource concerns

  • that we coming into our office,

  • we just really felt we needed to have some training

  • for our employees on how to handle salinity

  • and how to work with producers on salinity.

  • You know, the work that we're doing right now in North Dakota

  • on working with producers as NRCS

  • we are looking at trying to get into the rotation

  • more salt tolerant vegetation or trying to get cover crops

  • that are more salt tolerant of salinity--

  • to try to treat the saline areas,

  • but we're also looking at total landscape water use.

  • (narrator) While growing salt tolerant crops like alfalfa

  • and barley or putting land into CRP are long standing ways

  • of dealing with and fighting salinity, a third solution is

  • more expensive and potentially more controversial.

  • It's the installation of subsurface drainage pipes

  • that are perforated so they're put at a depth

  • to reduce the drought water levels below a level

  • that'll allow the water to rise to the surface.

  • And what it does is, it drains excess water

  • that is not needed for crop production.

  • It doesn't affect the crop, the water that the crop needs,

  • but it drains excess water, and it allows

  • better aeration of soil which is also important for crop growth.

  • And with that, the salts move with the water.

  • So wherever the water goes is where the salts are going to go.

  • Other than that, there are other things

  • with sodium levels in the soil.

  • If you have high sodium levels,

  • the potential to leech out the calcium salts

  • will change the physical properties of the soil,

  • and it can actually accentuate

  • or make the soils less fit for crop production.

  • There is some danger with understanding essence

  • of tile drainage, knowing your soils is very, very important

  • before you install tile drainage,

  • and having an understanding of the history

  • and the potential for sodium-affected soils

  • after you start to drain that water out.

  • Tile drainage works. The advantage of tile drainage

  • is that it allows the farmer to regulate

  • when it gets in the field and when it gets out of the field.

  • If there's a large rain, the land manager can

  • pretty much guarantee that within 3 to 5 days, you're

  • going to be able to get into that field with tile drainage.

  • Without tile drainage it might be 7 to 12 days.

  • (narrator) Roxanne Johnson with North Dakota State University Extension

  • is in the midst of a 5-year study on salinity,

  • including the impact of tile drainage.

  • Where you put that outlet is really, really important.

  • Don't put it upstream of someone's home

  • so it's running by their house so they have

  • excess water sitting in from of their homes.

  • [chuckles] I'm a farm girl, so I'm afraid

  • that if we don't have tile drainage that there won't be

  • farming as we know it in eastern North Dakota

  • because of the high saline levels in these fields.

  • You talk to these producers,

  • and it's the best thing since white bread, apple pie!

  • (narrator) But other research from Joleen Hadrich

  • looked into the economics of tiling

  • which can cost farmers nearly $600 per acre to install.

  • I did my analysis assuming $4.75 per bushel of corn,

  • and now it's trading

  • at $7.00 a bushel on the futures market.

  • Drainage tile would make a lot more sense now,

  • but at $4.00 corn and a yield of 120 bushels per acre,

  • the farmer would be losing between $2.00 to $20.00 an acre

  • if they put in drainage tile.

  • It is expensive, but it took land

  • that was virtually worthless

  • for annual crop production

  • and made it good to excellent crop production land.

  • Tile drainage, what we are doing here

  • in the Red River Basin is

  • installing drain tile to remove excess subsurface water.

  • There's really one reason why farmers are

  • installing drain tiles on their fields,

  • and it's for increasing crop production.

  • We've tiled fields that farmers tell me

  • are their saltiest fields, and in a few years,

  • probably 3 to 5 years,

  • they are yielding as good as their best fields.

  • You look back here,

  • and anytime you see a pump pumping water,

  • you know there's a perception

  • that you're making new water,

  • and that is untrue.

  • What we're doing is, we're

  • lowering the water table,

  • and we're creating a reservoir in our field.

  • We've done a variety of things.

  • We are drain tiling, trying to get rid of some of the salts

  • that naturally through the rain will percolate through the soil

  • and go out through the drain tile.

  • We've got an interesting project with the University of Manitoba.

  • There's a couple of Ph.D. students doing their thesis

  • on water movement and saline soils,

  • and we have got a replicated trial here

  • in the back of this farm of about 15 acres.

  • They will be trying to determine how the saline areas

  • are mitigated with drainage and irrigation.

  • (Dr. Cihacek) Once you take that water and move it somewhere--

  • you gotta move it somewhere-- put it into a drainage ditch.

  • The problem with our flat landscape is,

  • it's hard to move it any long distance.

  • The water that comes out of the drains contain salts.

  • Now, my concern is with the drainage that you can have

  • a transfer of a problem from one field to another field

  • or another area because that water is going to contain salts.

  • If the water cannot flow off freely, it ponds up.

  • Then we've got the potential of salinizing other land.

  • Some of the preliminary numbers that I've reviewed

  • suggest that the total dissolved solids

  • in some of the tile drains are very, very high.

  • I've seen them 10,000, 15,000 milligrams per liter--

  • some very high sulphate numbers also.

  • Now, one or two individually

  • probably doesn't have a great effect.

  • What's unknown is the cumulative effect

  • of widespread tile drainage on the tributaries

  • flowing into the Red River and the Red River itself.

  • We do know that nitrate, for instance, seems to be

  • very, very high in tile drainage waters.

  • Salinity is a global problem,

  • but the solutions to that should be and must be local.

  • (narrator) The causes of salinity are many,

  • as are the potential solutions.

  • The key for farmers and soil experts is

  • to curtail the problem before it reaches levels that have caused

  • economic collapse in other countries, in other times.

  • National, state and local solutions

  • will hopefully converge to win the battle.

  • Some of the crops as North Dakota shifting into

  • more of the corn belt types of production

  • with corn and soybeans.

  • We're going to see more problems emerge

  • with saline soils if we aren't careful.

  • (Dr. Hopkins) We have soils that are very, very productive,

  • but you can drive any road in North Dakota

  • and see examples of egregious erosion.

  • As government agencies, we need

  • to work with the growers--

  • corn growers, soybean growers and really try to address

  • this resource concern in North Dakota.

  • The universal advice which I would like to repeat is

  • instead of adapting the soil to the plant,

  • adapt the plant to the soil

  • as a biological long-term,

  • less expensive, and permanent solution.

  • Funding for "Salt of the Earth"

  • is made possible by an EPA Section 319 grant

  • administered by the North Dakota Department of Health.

  • the Eastern North Dakota

  • Resource Conservation and Development Councils,

  • with support provided by the...

  • ...helping people help the land,

  • and by the members of Prairie Public.

(Dr. Jaradat) We live in a world of salt, but we do not recognize it.

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大地之鹽 (Salt of the Earth)

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    Bing-Je 發佈於 2021 年 01 月 14 日
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