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ANALYSIS OF THE RELIEF ROLE IN THE KUR-ARAZ LOWLAND SOILS SALINITY BASED ON GIS TECHNOLOGY

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Amin Ismayilov at Institut soilscience and aqrochemistry of Azerbaijan National Academy of Sciences, Baku
Amin Ismayilov
  • Institut soilscience and aqrochemistry of Azerbaijan National Academy of Sciences, Baku
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ABSTRACT The reasons of the Kur-Araz Lowland soils salinity have been investigated in the article. An intensive development of the irrigative farming causes growth in agricultural crops production and strongly affects the salts migration of soils in these zones. To the most specialists’ mind the large zones underwent the salinity process as a result of incorrect fulfillment of the irrigative regime, agro technical rules and water losses in irrigation system. But, besides these reasons, there is an enough impact of the relief in salinization process and this factor wasn’t sufficiently investigated. One of its main causes connects with non-existence of the appropriate geoinformation technologies to perform geospatial analysis before. From this point of view the geoinformation technologies present large opportunities to investigate a relation of the soils salinization characters, spreading legitimacies, potential salinization danger with the relief at present. First of all, the digital salinization map of the Kur-Araz lowland soils was compiled on the basis of GIS to study a relief role in the soils salinization process. Then digital elevation model (DEM) was built. It was known that the relief of the research object zone changes at -28 m and +50 m intervals. A comparative analysis of the DEM with the digital salinization map of soils was performed. The obtained consequences indicate a close correlation of the relief factor with the salinization process of soils to some or other degree. KEY WORDS: GIS, soil salinity, DEM, digital map.
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PROCEEDING
EDITORS
Prof. Dr. Ferruh YILDIZ
Prof.Dr. Ramiz Mahmud oğlu MAMMADOV
Prof. Dr. Ekrem TUSAT
Assoc.Prof.Dr. Maharram SAMAD oglu Hasanov
Assoc.Prof.Dr. Zernura HAMIDOVA
Dr. Fatih SARI
Dr. Osman ORHAN
Hasan Bilgehan MAKINECI
Elnur SAFAROV
EURASIAN GIS 2018 CONGRESS
04-07 SEPTEMBER 2018 - Baku/AZERBAIJAN
ANALYSIS OF THE RELIEF ROLE IN THE KUR-ARAZ LOWLAND SOILS SALINITY
BASED ON GIS TECHNOLOGY
A.Ismayilova, A.Yasharb
aAzerbaijan National Academy of Sciences, Institute of Soil Science and Agro Chemistry, Laboratory of GIS-Soil, AZ1073, Baku,
Azerbaijan, amin_ismayilov@mail.ru
bNational Aviation Academy, Department of Aerospace, AZ1045, Baku, Azerbaijan, arshad.yasar@gmail.com
ABSTRACT
The reasons of the Kur-Araz Lowland soils salinity have been investigated in the article. An intensive development of the irrigative
farming causes growth in agricultural crops production and strongly affects the salts migration of soils in these zones. To the most
specialists’ mind the large zones underwent the salinity process as a result of incorrect fulfillment of the irrigative regime, agro technical
rules and water losses in irrigation system. But, besides these reasons, there is an enough impact of the relief in salinization process
and this factor wasn’t sufficiently investigated. One of its main causes connects with non-existence of the appropriate geoinformation
technologies to perform geospatial analysis before. From this point of view the geoinformation technologies present large opportunities
to investigate a relation of the soils salinization characters, spreading legitimacies, potential salinization danger with the relief at
present. First of all, the digital salinization map of the Kur-Araz lowland soils was compiled on the basis of GIS to study a relief role
in the soils salinization process. Then digital elevation model (DEM) was built. It was known that the relief of the research object zone
changes at -28 m and +50 m intervals. A comparative analysis of the DEM with the digital salinization map of soils was performed.
The obtained consequences indicate a close correlation of the relief factor with the salinization process of soils to some or other degree.
KEY WORDS: GIS, soil salinity, DEM, digital map.
294
1. INTRODUCTION.
An intensive development of the irrigation agriculture causes
growth in agricultural crops production and strongly affects the
salts migration in the soils. The large zones underwent the salinity
process as a result of incorrect fulfillment of the irrigative regime,
agrotechnical rules and water losses in irrigation system.
According to the statistical information of the last years 3 470 823
hectares of the soil resources in the Azerbaijan Republic
underwent erosion to some or other degree. 661 937 hectares of
1 421 634 hectares irrigative plain soils exposed to salinization,
but 480165 hectares to salonetzificationin the Republic. A total
plot in the agricultural areas in the Republic is 4 531 326 hectares
and 565 511 hectares from these plots underwent salinity. 152892
hectares are weak, 146235 hectares – mean, 223838 hectares –
strong salinized areas. Besides it 42 510 hectares of the plots
consist of saline lands. In all the plots exposed to salinity form
12,5% of the total agricultural areas. 508270 hectares of the
agricultural fields underwent solonetzification.
The given figures show a great importance of the soils in need of
the melioration measures in a total share of the agricultural areas.
That’s why preparation of maps based on exact and substantial
information is an important problem to prepare measures which
will be applied for the purpose of specifying such soils borders
and their normality. On other hand the large-scale field and
laboratorial works performance is necessary to obtain important
information on soil cover. It is possible by using only from the
modern technologies to economize time and financial expenses
over and again in fulfilment of this work. Therefore using of the
GIS opportunities to study salinization process, to prognosicate
and perform monitoring in soils, is one of the actual themes
(.Mehdiyev A.Sh, Ismayilov A.I., 2011). Thats’s why a quick
development of the information technologies, especially GIS
technology, increase of the RS data punctuality and opportunities
created a large condition for DEM establishment and their
application fulfilment. DEM establishment is widely used in
morphological (geomorphological), geological, hydrological
research of the earth’s surface, in composition of the relief maps
and physical models, in soil utilization, Landscape planning,
infrastructural projection and other areas. One of the superior
characters of the DEM information conveyance parts is a
presence of Z coordinate besides X and Y coordinate.
2. MATERIAL AND METHODS.
A research object is the Kur-Araz Lowland. The soil-cover of the
Kur-Araz lowland underwent intensive antropoghenic effects and
one of its main reasons consists of more attraction of these zones
to the agricultural production. An important part of lowland
exposed to salinity, water and wind erosion, here various
antropoghenic effects heaviness substantiates to consider these
zones inconstant ecologically and inevitable negative processes
can be happened in future. Just study of salinity rate, salinity
reasons of these soils and spreading of this process inside space
is considered on of the actual ecological problems because of the
above mentioned reason. The utilization method of the relief
digital elevation model was used to investigate a relief role in
soils salinity process of the Kur-Araz lowland. DEM is widely
used in soil utilization, soil surface research, especially soils
salinization. DEM is an unexampled means in an investigation of
the soils salinity distribution according to the height. The different
terms are used in “Digital Elevation Model” equivalent of the
English scientific references. It is possible sometimes to meet
with the same and conflicting facts among the models. Digital
Elevation Model (DEM) is mostly found among these terms. The
Digital Terrain Model (DTM), Digital Surface Model (DSM)
terms are also used besides DEM in the scientific literatures. In
some cases DSM reflects buildings, trees and other objects on the
earth besides the earth’s surface. Unlike DSM, the DTM is only
attracting earth’s surface, here buildings, trees and other objects
on the earth’s surface aren’t taken into account (Li, Z., Zhu, Q.
and Gold, C. 2005). Generalizing of DEM and DSM terms, the
DTM term is often used, so the height information is presented
without any information about the earth’s surface (Waibel M,
1995). On the other hand the DEM and DTM terms are identified
or the DEM term is presented as a structural part of DTM
(Peckham R.J., Jordan G., 2007). The DEM and DSM terms are
identified in some sources (Tomaz Podobnikar, 2009). DEM is
noted as GRID with a regular interval and DTM as three
dimensional model TIN (Triangular Irregular Network) in the
Internet pages.
As is shown in the scientific literatures, generally DEM
can be presented as GRID with a regular interval or DTM – three
– dimensional model. The data providers are used like USGS,
ERSDAC, CGIAR, SPOT Image, in general the DEM term as
DSM and DTM terms. DEM can be in both raster and vector
formats. GRID is in raster, but TIN in the vector form. The
tecnical means like DEM programmetry, Lidar, if SAR, Land
Surveying and etc. can be obtained. DEM is mainly established
on the basis of the information obtained by the Remote Sensing
methods, but sometimes it is built as a result of the field – research
works. DEM is often used in GIS and it forms a basis of digital
maps preparation of the relief. DSM is mostly used for the
landscape modelling, urban modelling and visual programs. But
DTM is used in stream, flood and drainage modelling, soil
utilization researches, geological and such investigations. An aim
of the research is to analyse a relief role in soils salinization. For
this purpose a salinity map of the Kur-Araz lowland soils (s 1:100
000) was compiled on the basis of GIS.
Figure 1. Salinity map of the Kur-Araz lowland soils
(s 1:100 000)
An area of the Kur-Araz lowland soils was given by hectare and
percentage salinity degrees on the table.
295
№
Salinity degree
Dry
residue
Plot on
gradation
Plot by
percentage
1
Unsalinized
<0.25
3509.2
18.3
2
Little salinized
0.25-0.5
4071.5
21.2
3
Mean salinized
0.5-1.0
4799.1
25.0
4
Strong salinized
1.0-2.0
5017
26.2
5
Very strong
salinized
2.0-3.0
1434.3
7.5
6
Saline soils
>3.0
334.8
1.7
Table 1. Areas table on soils salinity degrees
DEM must be established to study a relief role in soils salinity
process. For this purpose morphometric indices of relief (height,
slopes exposition, indication) must be determined, the
hydrological net must be built, watershed net must be constructed,
the size of the plane and surface areas in the relief must be
calculated. A role of DEM and definition of their chances have
been investigated in these problems solution. The usage
opportunities of the various methods have been revealed for DEM
establishment of the Kur-Araz lowland. The sources which are
widely used for the scientific researches are considered National
Aeronavtic and Space Administration (NASA) of the USA.
ASTER GDEM (Advanced space borne Thermal Emission and
Reflection Rediometer, Global Digital Elevation Model) which
are products of Japan Ministry of Economy, Trade and Industry
(Adrian W. Graham, Nicholas C. Kirkman, Peter M. Paul, 2007).
One of the main proprietaries of this source is availability for the
users. The investigative ability of ASTER GDEM is 1 arcsecond.
Arcsecond changes on geographical latitudes depending on the
earth form. One pixel width on the ecvator can be calculated by
(1) and height by (2) formula if we take into account that a length
of the ecvator circle is 40076 km (E), but a length of the meridian
circle is 40009 km (M).
(1)
1000*
3600
1
*
360
0
0
M
Y
(2)
We find from the formula that
mX 92.30
,
mY 87.30
. (here
3600 is a quantity of seconds in one degree).
Not depending on geographical latitude Y is always
constant, but X changes. X quantity can be calculated by (3)
formula if we take account that the Ku-Araz lowland center is
situated in the 400 north latitude.
0
5.40 40cos*
0XX
(3)
In this case an availability of ASTER GDEM for Kur-Araz
lowland will be X=23.69 m, Y=30.87 m.
Figure 2. DEM of Kur-Araz lowland.
The obtained analysis of DEM shows by the GIS program that an
area of the research object is 19161.6 km. 59,4% (11383.1 km2)
of this zone is situated below sea-level, 40.6% (7778.5km2)
above sea-level. The areas of which absolute height is higher than
0-50 m form 8,5% (1627.7km2), the areas which are situated
higher than 50-100 m form 19,5% (3737.6 km2), the areas of
which absolute height is higher than 100 m metre form 12,6 %
(2413.2 km2) of the zone.
№
Height
gradation
Plot on
heights
Plot by
percentag
e
1
<-10
8863.5
46.3
2
-10-0
2519.6
13.1
3
0-50
1627.7
8.5
4
50-100
3737.6
19.5
5
>100
2413.2
12.6
Table 2. Areas spreading table for the relief height
The indications by the salinity map of the Kur-Araz lowland and
DEM model obtained as a result of the analysis based on GIS are
given on the following table. The obtained consequenses visually
demonstrate an intensiveness of the soils salinity process in
comparatively low levels of the relief.
№
Salinity rate
QQ
<-10
-10-0
0-50
50-100
>100
1
Unsalinized
<0.25
833.4
211.6
249.9
1162.6
1051.2
2
Little
salinized
0.25-0.5
1853.6
449.1
324.6
952.2
491.7
3
Mean
salinized
0.5-1.0
2162.6
816.1
488.7
943.4
387.5
4
Strong
salinized
1.0-2.0
2706.7
858.4
429.7
561.3
457.6
5
Very Strong
salinized
2.0-3.0
1016.1
164.4
117.5
111.2
24.4
6
Saline soils
>3.0
290.6
19.9
17.2
6.8
0
Table 3. Spreading of salinity rate for the relief height
296
3. CONCLUSION
The relief role has been revealed in exposing the Kur-Araz
lowland soils to the salinization in the article. With this purpose a
salinity map of the Kur-Araz lowland soils has been composed on
the basis of GIS. Then DEM of the zone was established. A
comparative analysis of the salinity indications in soil areas with
the height indices of the relief have been performed on the basis
of GIS. It was visually grounded that the relief is one of the main
factors in exposing of the soil plots to salinization.
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297
... Assessing soil salinity is a critical task for the Kur-Araz basin (600,000 ha) of Azerbaijan, which is located in the shoreline area (situated below sea level up to 30 m with <300-400 mm annual precipitation) and has wide drainage networks. Currently, 60% of the cultivated and irrigated land of the basin has clayey soil in the root zone and is characterized by various degrees and types of salinity ( Figure 1) [7][8][9]. The problem of salinity in the Kur-Araz basin of Azerbaijan, as well as in many semi-arid and arid regions or drylands of the world, is expected to increase with the ongoing climate change and shortage in fresh water. ...
... Thus, frequent monitoring of salinity level is important for water resources allocation and sustainable management of salt-affected soils, which may have significant economic ramifications if ill-managed [10]. [9]). Salinity degree is given by total soluble salts (TSS, %). ...
... Sustainability of the agroecosystem in salt-affected lands could be preserved by studying salinity related soil processes (e.g., the interactions between root-zone environment [9]). Salinity degree is given by total soluble salts (TSS, %). ...
OUTCOME document GLOBAL SYMPOSIUM ON SALT-AFFECTED SOILS
Conference Paper
  • Oct 2022
Introduction, scope and main objectives. Soil salinity severely affects ecosystem quality and crop production. Large amount of data on soil salinity has been collected in the Commonwealth of Independent States (CIS, formerly USSR) and many other countries during more than 70 years, but its current use is complicated because in these countries salinity was expressed by (i) total soluble salts (total soluble salts, TSS, %) and (ii) eight salinity types (chemistry) determined by the ratios of the anions and cations (Cl-, SO4 ²+, HCO3 ²-, and Na+, Ca²+, Mg²+) in diluted 1:5 soil/water extract without assessing electrical conductivity (EC) (Basilevich and Pankova, 1968; Hazelton and Murphy, 2016). Measuring the EC (1:5) is more convenient and can be easily linked to saturated paste extract, ECe (Sonmez et al., 2008; He et al., 2013; Kargas et al., 2020). Yet, EC is not only affected by salt concentration but also by salinity chemistry (Corwin and Scudiero, 2019, Ismayilov et al., 2021). The latter also influences soil physical characteristics, soil-water-plant relations and abiotic stresses (Levy et al., 2005; Rengasamy, 2010). The objective of this study was to examine the relationship between EC and TSS of soils in a diluted extract (1:5) for the eight classic salinity types used in CIS. Methodology. Extracts (1:5) of 1100 samples of a clayey soil (0–30 cm) collected from cultivated semi-arid and arid regions of the Kur-Araz basin, Azerbaijan, were analysed for EC, TSS, soluble cations (Na+, Ca²+, Mg²+), and anions (HCO3 ²- , Cl-, SO4 ²+). Eight types of salinity chemistry were formed in light of the geomorphological conditions, irrigation, and drainage history in the basin. Results. Results revealed that (i) the variation in the proportional relations (R2=0.91–0.98) between TSS (0.05%–2.5%) and EC (0.12–5.6 dS/m) could be related to salinity type, and (ii) the proportionality coefficient of the relations (TSS = a EC; a= 0.313–0.447) decreased in the following salinity chemistry order: SO4 > Cl(SO4)–HCO3 > Cl(HCO3)–SO4 > SO4 (HCO3)–Cl > Cl. Formerly reported mean value of the coefficient (a = 0.336) was significantly lower than our mean value (a = 0.408), but still within the range of coefficients obtained in our study (a = 0.313– 0.447). Discussion. The traditional reported coefficient (TSS = 0.336 EC) is based on soil salinity dominated by NaCl. This coefficient was (i) comparable for chloride dominant salinity type (0.313, 0.323, and 0.336 for Cl, SO4–Cl, and HCO3–Cl, respectively); (ii) similar but somewhat lower for the sulfate dominant type of salinity (0.369 and 0.371 for Cl–SO4 and HCO3–SO4, respectively); and (iii) lower for sulfate itself and the carbonate and bicarbonate dominant type of salinity (0.447, 0.402, and 0.396 for SO4, Cl–HCO3, and SO4–HCO3, respectively). Thus, new TSS= a EC relation were (and should be) determined by ion characteristics or salinity type (Ismayilov et al., 2021). Conclusions. The findings suggest that once soil salinity type is established, EC (1:5) values can be used for evaluation of salinity degree in irrigated land in the context of sustainable soil and crop management. Results can assist in application of advanced precision agriculture and management strategies associated with mapping, leaching fraction, salinity stress, and selection of cultivars tolerance to salinity level and deterioration of soil physical quality. Acknowledgements. The support of Arid Land Research Center, Tottori University and Institute of Soil Science and Agrochemistrty, ANAS, is acknowledged. References. Corwin, D.L. & Scudiero, E. 2019. Chapter One–Review of soil salinity assessment for agriculture across multiple scales using proximal and/or remote sensors. In D.L. Sparks, ed. Advances in Agronomy, pp. 1–130. Academic Press. Bazilevich, N.I. & Pankova, E. I. 1968. An experience of soil classification according to the salinity status. Soviet Soil Science, 11: 3–16 (in Russian with English abstract). Hazelton, P. & Murphy, B. 2016. Interpreting Soil Test Results. What Do All the Numbers Mean? CSIRO Publishing. 201 pp. He, Y., DeSutter, T., Hopkins, D., Jia, X. & Wysocki, D.A. 2013. Predicting ECe of the saturated paste extract from value of EC1:5. Canadian Journal of Soil Science, 93(5): 585–594. Ismayilov, A.I., Mamedov, A.I., Fujimaki, H., Tsunekawa, A. & Levy, G.J. 2021. Soil Salinity Type Effects on the Relationship between the Electrical Conductivity and Salt Content for 1:5 Soil-to-Water Extract. Sustainability, 13(6): 3395. Kargas, G., Londra, P. & Sgoubopoulou, A. 2020. Comparison of Soil EC Values from Methods Based on 1:1 and 1:5 Soil to Water Ratios and ECe from Saturated Paste Extract Based Method. Water, 12(4): 1010. Levy, G., Goldstein, D. & Mamedov, A. 2005. Saturated Hydraulic Conductivity of Semiarid Soils: Combined Effects of Salinity, Sodicity, and Rate of Wetting. Soil Science Society of America Journal, 69. Rengasamy, P. 2010. Soil processes affecting crop production in salt-affected soils. Functional Plant Biology, 37. Sonmez, S., Buyuktas, D., Okturen, F. & Citak, S. 2008. Assessment of different soil to water ratios (1:1, 1:2.5, 1:5) in soil salinity studies. Geoderma, 1–2(144): 361–369.
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... Assessing soil salinity is a critical task for the Kur-Araz basin (600,000 ha) of Azerbaijan, which is located in the shoreline area (situated below sea level up to 30 m with <300-400 mm annual precipitation) and has wide drainage networks. Currently, 60% of the cultivated and irrigated land of the basin has clayey soil in the root zone and is characterized by various degrees and types of salinity ( Figure 1) [7][8][9]. The problem of salinity in the Kur-Araz basin of Azerbaijan, as well as in many semi-arid and arid regions or drylands of the world, is expected to increase with the ongoing climate change and shortage in fresh water. ...
... Thus, frequent monitoring of salinity level is important for water resources allocation and sustainable management of salt-affected soils, which may have significant economic ramifications if ill-managed [10]. [9]). Salinity degree is given by total soluble salts (TSS, %). ...
... Sustainability of the agroecosystem in salt-affected lands could be preserved by studying salinity related soil processes (e.g., the interactions between root-zone environment [9]). Salinity degree is given by total soluble salts (TSS, %). ...
Soil Salinity Type Effects on the Relationship between the Electrical Conductivity and Salt Content for 1:5 Soil-To-Water Extract
Article
Full-text available
  • Mar 2021
Soil salinity severely affects soil ecosystem quality and crop production in semi-arid and arid regions. A vast quantity of data on soil salinity has been collected by research organizations of the Commonwealth of Independent States (CIS, formerly USSR) and many other countries over the last 70 years, but using them in the current international network (irrigation and reclamation strategy) is complicated. This is because in the CIS countries salinity was expressed by total soluble salts as a percentage on a dry-weight basis (total soluble salts, TSS, %) and eight salinity types (chemistry) determined by the ratios of the anions and cations (Cl−, SO42−, HCO3−, and Na+, Ca2+, Mg2+) in diluted soil water extract (soil/water = 1:5) without assessing electrical conductivity (EC). Measuring the EC (1:5) is more convenient, yet EC is not only affected by the concentration but also characteristics of the ions and the salinity chemistry. The objective of this study was to examine the relationship between EC and TSS of soils in a diluted extract (1:5) for eight classic salinity types. We analyzed extracts (1:5) of 1100 samples of a clayey soil (0–20 cm) collected from cultivated semi-arid and arid regions for EC, TSS, soluble cations (Na+, Ca2+, Mg2+), and anions (HCO3−, Cl−, SO42−). Results revealed that (i) the variation in the proportional relationships (R2 ≥ 0.91–0.98) between EC (0.12–5.6 dS m−1) and TSS (0.05–2.5%) could be related to salinity type, and (ii) the proportionality coefficient of the relationships (2.2 2–3.16) decreased in the following order of salinity type: SO4 < Cl(SO4)–HCO3 < Cl(HCO3)–SO4 < SO4 (HCO3)–Cl < Cl. The findings suggest that once the salinity type of the soil is established, EC (1:5) values can be safely used for the evaluation of the soil salinity degree in the irrigated land in the context of sustainable soil and crop management.
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