Salinization and amelioration possibilities of salt affected soils on the Hungarian Plain

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SUSTAINABLE LAND USE AND AMELIORATION OF SALT
AFFECTED SOILS
Lajos Blaskó Debrecen University Agricultural
Centre Karcag Research Institute E-mailblasko_at_dat
eki.hu
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The practice of reclamation of SAS in Hungary is
two centuries old

• the first guide on this topic
• SÁMUEL TESSEDIK (1804) Über die Kultur und
  Benützung der so genannten Székes-Felder(Salt
  affected soils) in der Gegend an der Theiß.
• Lübeck, I.R. Patriotisches Wochenblatt f. Ungarn.
• revaluation of the achievements from viewpoint of
  sustainability

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sustainability of amelioration
Sustainable agriculture
Sustainable agriculture integrates three main
goals--environmental health, economic
profitability, social and economic equity.
For meeting the demands of ecological and
economical points of sustainability the
amelioration of soils must be revaluated first of
all because of the changing climatic and
economical situation.
Community Society
Economy
Environment
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According the soil survey (SZABOLCS 1971,
VÁRALLYAY 1992), the salt affected soil cover in
Hungary about 1 million ha. (about 10 of total
area)
What to do with SAS?
Trans Tisza Region
Karcag
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Goals
For an established land use decision - among
others - the following questions must be
answered ?What is the main trend of natural
soil forming processes? What are the most
effective means of soil improvement? It is a
fundamental question if a negative (decreasing)
salt balance is without subsurface drainage
attainable or not What is the degree of the soil
quality changes for shorter and longer term
after amelioration? What are the most suitable
cultivated crops of improved SAS
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Material and methods
The paper is based on the research results
achieved by the following facilities Karcag
lysimeter experiment
salt balance monitoring Soil Information
Monitoring System (TIM). Karcag-puszta long term
experiment
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Summarized results of salinization monitoring

• According to the open air monitoring - in line
  with lysimeter results - in case of rain fed
  agriculture in the last two decades the
  increasing salt content was not characteristic,
  not even on the territories where earlier salt
  accumulation problems happened.
• It means, that the natural sinking of
  ground-water level is favorable from viewpoint of
  sustainability of amelioration.

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More detailed results of Karcag-puszta
experimental field

• In 1977 the Research Institute of Debrecen
  Agricultural Univ. established complex
  amelioration stations on the main soil types of
  the Hungarian Plain, among them the Karcag-puszta
  experimental field represents the facility on
  salt affected soil. This site were chosen because
  it typified much of the salt affected soils of
  the Eastern part of the Hungarian Plain.

This great spatial variety rises special
methodological problems in case of plot
experiments Theoretically the disadvantages
effect of heterogenety could be moderated by the
increase of the number of the replication, but
this method is practically not applicable in the
case of soil reclamation or amelioration
experiments with drainage due to the limited
capacities
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Sampling

• To determine the change of the soil properties1
  samples were taken from 112 surveyed points of 16
  plots in 1977, 1981, 1989 1995 and2000. The soil
  was sampled to the depth of 110 cm by each 10 cm
  deep layer. Beyond the sampling points 224
  elevation reference points were also surveyed,
  hence the z co-ordinates provide the
  possibility of 3-D modelling (DTM
• 1 The examined soil properties pH (H2O), pH
  (KCl), Y1, CaCO3, Na2CO3, KA, exchangeable Ca-,
  Mg-, K-, and Na, salt ().

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m above Baltic sea level
Contour map of the experimental area
The altitude difference between the higher and
lower point of experimental field is 0.9 m
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Micro relief
The micro-relief of salt affected soil forms
basins and valleys with different run-off
characteristics.
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Run-off/run-on situations (SURFER 7.0)
In the areas with different exposure specific
water-regimes are formed through water run-off
and run-on. As a consequence of limited
infiltration the rainwater runs off the higher
parts. The run on water keeps the deeper parts of
the catena position longer wet
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Subtypes of Meadow solonetz on the experimental
field

• Mainly depending on the catena - moving from the
  highest position to the deeper one - the crusty
  (A 0-7 cm), medium (A8-20 cm) and deep (A gt 20
  cm) subtypes of the meadow solonetz soil can be
  found. On 25 of the soil cover in addition to
  the solonetzic character (ESPBhor gt 5). The
  solonchaky feature (water soluble salt content in
  the top layer gt 0,15) can be found as well. At
  the deepest catena position the soil is salt
  affected only in the deeper layers, so it
  belongs to the type of non salt affected meadow
  soil.

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The chemical reclamation was made site specific

• On the soils with neutral or slightly acidic top
  layer lime was applied, while on the soils with
  alkaline top layer gypsum was used

For regulation of drainage either surface or
subsurface drainage was constructed. The surface
drainage was made by outlet furrows. For
internal drainage a tube system with an average
depth of 1 m and 5, 10, 15 m drain spacing was
constructed.
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Exemplars of site specific reclamation
Treatment Soil subtype Treatment code
DIGO (Spreading loess on the surface)400m3/ha crusty meadow solonetz (2)
Gypsum in A horizon crusty meadow solonetz (3,17)
Gypsum in A and B horizon crusty meadow solonetz (4,16)
Lime in A horizon/gypsum in B horizon 5 m drain crusty meadow solonetz (7,12)
Lime in A horizon/gypsum in B horizon 15 m drain crusty meadow solonetz (15)
Lime in A horizon/gypsum in B horizon medium meadow solonetz (8)
Lime in A horizon deep meadow solonetz (5)
Treatment DIGO is the oldest amelioration
method of SAS in Hungary. Originally it was
suggested by TESSEDIK 200 years ago. For
improvement of SAS the CaCO3 containing loess is
mined and spread an amount of 200-400m3/ha
(depending on the soil quality) on the surface of
SAS.
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The fertility of a solonetz soil depends on the
depth of leached A hor.
A-hor
water and nutrient storage capacity rooting zone
B-hor
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Change of depth of A-horizon with low Na content
(velocity of improvement)
By means of drainage the average deepening of
leached A-horizon was 20 cm/10 ys. Without
drainage the thickness of the fertile topsoil
with low salt content has deepened with
approximately 10 cm/10 ys.
A-hor
B-hor
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• Winter wheat Y 3,32 0,02X -1,15E-4 X2
  R20,4595 n16 p0,0183
• Sunflower Y 0,52,028 X -9,99E-2X2
  R20,7380 n16 p1,66E-4
• Alfalfa hay Y 1,41 0,03X -1,04E-4 X2
  R20,7888 n16 plt0.0001
• Millet Y 0,930,02 X -9,29E-5
  X2R20,6669 n16 p7,88E-4
• Gr.sorghum Y 2,48 0,07X -4,92E-4 X2
  R20,1752 n15 p0,3149
• Winter barley Y 1,000,03X 1,00E-6 X2
  R20,2982 n16 p0,1001

Relationship between depth A-horizon and the
yield of different crops
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ConclusionLand use alternatives

• For arable land-use reclamation of sodic soils
  with deeper leached upper horizon and deeper
  ground water level must be preferred.
• If the leached A-horizon is shallower than 15-20
  cm and the ground water level frequently higher
  than 1.5 m the SAS can more economical be used as
  a pasture

For meeting the demands of ecological and
economical points of sustainability
velocity of improvement relationship between
depth A-horizon and the yield of different crops
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Land use possibilities
A10-20cm
A0-10cm
third part hay-field and grazing ground
Agt20cm
third part arable land (mainly winter wheat )
third part in original state
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• Thanks for your attention.