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I.Boldea, C. Sigmirean, D.-M.Buda
THE CHALLENGES OF COMMUNICATION. Contexts and Strategies in the World of Globalism
266 Section: Social Sciences
THE MORPHOMETRIC CHARACTERIZATION OF THE HYDROGRAPHIC
NETWORK ON THE CALIMANI MOUNTAINS USING GIS TECHNIQUES
Lucian Moldovan
Teaching Assist., PhD Student, ”Dimitrie Cantemir” University of Tîrgu Mureș/
”Babeș-Bolyai” University of Cluj-Napoca
Abstract: The study indicates that the analysis of the morphometric parameters using Geographic
Information Systems (GIS) is a viable method in identifying the geomorphological characteristics and
analyzing the properties of the hydrographic basins in the mountainous area of the Calimani massif. For the morphometric component evaluation we used the global altimetric numerical model Shuttle Radar
Topography Mission (SRTM) with a resolution of 25 m. The GIS analysis methods of satellite data
provide us with a very efficient and time saving solution, and with an exact technique for the morphometric analysis of extensive areas. For the validation of the obtained results we used the
topographic maps 1: 25000 and the ortho-photo-maps offered by the National Agency of Cadastre and
Real Estate Advertising (ANCPI). The morphometric parameters of the hydrographic basins were determined by ArcGis computer based mapping programs (ESRI). Of these, the most important are: the
length of the basin, the width, the length and density of the hydrographic network, the surface of the
basin, etc. The obtained results can be used in the management of the studied area but also in the
subsequent studies.
Keywords: GIS, Hydrographic network, Morphometry, Geoprocessing, Watershed Delineation
Introduction
Delimitating river basins, generating hydrographic network and determining the morphometric
characteristics of rivers are key factors in hydrological studies. Until three decades ago, these
activities have traditionally been done topographically with topographic maps and aerial
photographs. Nowadays, with the emergence of new techniques and the development of
computer operations, these procedures are much easier to elaborate, being widely deployed using
geographic information systems.
Studied area
The studied area occupies the north-western part of the central group of the Eastern Carpathians,
being the largest volcanic massif in Romania. To the north it is delimited by the depression area
of Dornelor and Bargaului Mountains; to the east - the series of depressions: Şaru Dornei,
Păltiniş, Bilbor, Secu separates it from Bistrita Mountains. To the southeast are bounded by
Gurghiului Mountains. The southern limit is given by the Mureş defile that separates the
Gurghiului Volcanic Mountains. In the west, the hillsides of Caliman make the passage to the
Transylvanian Plateau.
I.Boldea, C. Sigmirean, D.-M.Buda
THE CHALLENGES OF COMMUNICATION. Contexts and Strategies in the World of Globalism
267 Section: Social Sciences
Material and methods
The methodology for this
study comprised two major stages.
The first stage consisted in the
preparation of the cartographic
material and the extraction of all the
elements that are necessary in
studying the morphometry of the
hydrographic networks. The second
stage analyzed the main
morphometric elements of a
hydrographic basin.
The geomorphologic aspects
were obtained with the Digital
Elevation Model (DEM), prepared
from SRTM (Shuttle Radar
Topography Mission) with a
resolution of 25 m. For the correction
and validation of the obtained data we used topographic maps with a scale of 1: 25,000 and
satellite images provided by Google-maps, and the National Agency for Cadastre and Real Estate
Advertising (ANCPI).
For the preparation of the cartographic material and for the morphometric elements
analysis (surface, perimeter, density, slope, etc.) we used ArcGIS 10.5.
Results and discussion Extracting the drainage network from DEM was carried out in three stages:
- correcting errors that may occur in DEM by filling the existing gaps in the pattern or leveling
the unnatural peaks in DEM; this is done by running the ArcToolbox - Spatial Analyst Tools-
Hydrology – Fill;
- determining the flow direction which is set by the direction of the steepest descent, or the
maximum drop, from each cell. This is calculated as follows: maximum drop =
change_in_z-value / distance * 100 with the help of ArcToolbox - Spatial Analyst Tools-
Hydrology- Flow Direction
- calculating possible flow accumulations:
this tool calculates the accumulated flow
as the sum of all the cells flowing in each
Fig.3 Coding the flow direction
Fig.4 Determining possible accumulation
Fig.1 Calimani Mountains Positioning
Fig.2 Profile view of a sink before and after running Fill and Profile view of a peak before and after running Fill
I.Boldea, C. Sigmirean, D.-M.Buda
THE CHALLENGES OF COMMUNICATION. Contexts and Strategies in the World of Globalism
268 Section: Social Sciences
descending cell in the output raster. Thus, the cell that does not receive water from the other
cells receives the value 1, and for cells that receive water from multiple sources, they are
added together with the value 1. In order to obtain the raster, use the command ArcToolbox -
Spatial Analyst Tools- Hydrology - Flow Accumulation
- The Flow Accumulation tool calculates accumulated flow as the accumulated weight of
all cells flowing into each downslope cell in the output raster. If no weight raster is
provided, a weight of 1 is applied to each cell, and the value of cells in the output raster is
the number of cells that flow into each cell (http://desktop.arcgis.com/en/).
- previous results can be reclassified to remove insignificant water streams. The range of
values of the raster overlapping on the analyzed territory is 0-5.41. By comparative analysis
with topographic maps with the scale of 1: 25000, some water courses were eliminated,
considered insignificant, ie non-permanent water courses. Using the Raster Calculator tool,
the values between 0 and 1.8 were removed, with the help of "Flow_Accumulation" = 1.8,
"Flow_Accumulation"), meaning that all cells with an equal or lower value than 1.8 were
eliminated. Finally, the hydrographic network from the entire analyzed area was obtained.
- this method is very fast, making the
time necessary for these analyzes
very effective, the errors being
very small. Their removal was
done manually by deleting the
extra generated points.
- the last step is delimitating the
river basins. To obtain this, the
accumulation points were
determined in a new shapefile file.
The points were positioned at the
extremity of the analyzed territory
in order to enclose the possible maximum. Non-enclosed areas are very small, which actually
represent small fragments of the hydrographic basins that do not have their development on
Fig.5 Determinarea acumularii posibile
RECLASSIFY
Fig.6 Errors in generating the hydrographic network
I.Boldea, C. Sigmirean, D.-M.Buda
THE CHALLENGES OF COMMUNICATION. Contexts and Strategies in the World of Globalism
269 Section: Social Sciences
the territory of Calimani Mountains. The command used in ArcGIS to set the limits of river
basins is: ArcToolbox - Spatial Analyst Tools – Hydrology –Watershed
When you delimit
hydrographic basins or map
the hydrographic network, go
through a series of steps.
Certain steps are mandatory,
while others are optional
depending on the
characteristics of the input
data. The drainage direction
of a stream will always be to
the lowest cell. Once the
direction in each cell is
known, it is possible to
determine which and how
many cells flow in any given
cell. This information can be
used to define the boundaries (limits) of the river basin and the hydrographic network. The
following diagram shows the process of extracting hydrological information such as river basin
boundaries and hydrographic network from a digital terrain model (DEM).
Fig.8 The hydrographic network of Calimani Mountains
Morphometric elements of the hydrographic basins
Fig.7 Flowchart shows the process of extracting hydrologic
information (http://webhelp.esri.com)
I.Boldea, C. Sigmirean, D.-M.Buda
THE CHALLENGES OF COMMUNICATION. Contexts and Strategies in the World of Globalism
270 Section: Social Sciences
The peculiarities of hydrological processes and phenomena in a hydrographic basin are
determined by the features it represents, namely: surface, length, width, shape, maximum
altitude, minimum altitude, etc..
The surface of the
hydrographic basin is the size of
the territory from which a
mainstream collects its water.On
the analyzed area there were
identified 6 hydrographic basins
with surfaces over 50 km2, 4 with
surfaces between 30-50 km2, 3
with 20-30 km2, the most
numerous being the small ones at
the extremity of the massif , i.e.
10 with surfaces between 10-20
km2 and 17 with surfaces under 10
km2, totalling 40 hydrographic
basins. The hydrographic basins
smaller than 2 km2 resulting from
these processes were excluded from the morphological analysis.
The surface of the hydrographic basin is one of the basin morphometric indexes
commonly used in hydrologic studies due to its important role in water flow. Thus, the lower the
reception basin, the better the hydrological regime of the river reflects the contribution of the
supply sources (pluvial and nival). With the increase of the surface, the effect of precipitation
and melting of the snow layer is slower and the flow variabilitymore attenuated (Pișotă I, Zaharia
Liliana, 2003).
The watershed is the line separating neighbouring hydrographic basins, linking the
highest elevation points. In a plan, this is the perimeter of the hydrographic basin, with a very
important role in calculating the hydrographic basin coefficient. The coefficient of development
of the catchment of the basin, introduced by Cebotarev, indicates the shape of the basin and is
calculated as follows: Kcum = Lc / Pc where Lc is the length of the catchment of the
hydrographic basin and Pc is the perimeter of the circle with a surface equal to the surface of the
basin.
The length of the basin, although is an important element
in characterizing the size of the river basins, its obtained values
are not always conclusive. In practice, this parameter is used to
show the distance between the point of sinking or confluence and
a point on the watershed, in the direction of the spring(Zăvoianu
I, 2006). Two parameters are used:
- The maximum length (Lmax), as the distance between the
river‘s spring and the spill, measured parallel to the main
drainage line.
- The average length (Lm) as the ratio between the surface of the
basin (Fb) and its width (B): Lm = Fb / B
The width of the river basin, as well as its length, is a
morphometric parameter used in defining the shape of the basin.
Fig.9 Surfaces and perimeters of hydrographic basins
Fig.10 Main components of the
hydrographic basin
I.Boldea, C. Sigmirean, D.-M.Buda
THE CHALLENGES OF COMMUNICATION. Contexts and Strategies in the World of Globalism
271 Section: Social Sciences
We can consider a maximum width and an average width. The maximum width is considered to
be the line joining the furthest points, perpendicular to the length of the basin. The average width
is the ratio between the surface and the length of the hydrographic basin lmed = F / L.
The form factor
RE. Horton considers that a normally developed basin must be in the shape of a pear.
Horton proposed the form factor (Ff), having a square as a reference form, calculated according
to formula:
𝐹𝑓 =𝐹
𝐹𝑝²
where: F is the surface of the hydrographic basin and Fp is the area of the square whose side is
equal to the maximum length of the basin.
In 1953, V.C. Miller proposed, for the appreciation of the shape of the basin, the
circularity ratio (β) or the degree of deviation from the circular shape. That is, the ratio between
the perimeter of the circle (Lc) which has the same surface as that of the hydrographic basin and
its perimeter (Lp). It is obtained with the equation:
𝛽 =𝐿𝑐
𝐿𝑝=2 𝜋𝐹
𝐿𝑝
A circular basin has a maximum efficiency of the movement of runoff, whereas an
elongated basin has the least frequency.
The elongation ratio (Ra), Gravelius and Schumm proposed the circle as the reference
form, but the elongation ratio was defined by the ratio of the circle diameter with the same
surface as the basin (Dc) and the maximum length of the basin (Lb).
𝑅𝑎 =𝐷𝑐
𝐿𝑏Dc= 2 π r r=C / 2 π
Depending on this coefficient, we can have four types of basins: a slightly elongated
basin, where Ra is between 1.12 and 1.20, a moderately elongated basin, where Ra is between
1.20 and 1.30, a heavily elongated basin, where Ra is between 1.30 and 1.50 , a very elongated
basin, where Ra is over 1.50.
The altitude of the hydrographic basin is a morphometric parameter with a particular
influence on hydrological processes. Nearly all meteorological phenomena depend on it, which
then reflects on the characteristics of the hydrological elements (Pișotă I, Zaharia Liliana,2003).
In characterising a hydrographic basin from an altimetric point of view, the following parameters
can be used: maximum altitude, minimum altitude (corresponding to the main river's spout) and
average altitude.
The average altitude of the basin (Hm) is a very important parameter used to highlight
the particularities of the
genesis and water regime,
the evapo-transpiration and
the flow coefficient, in
relation to the average
altitude of the basins. It
shows at what average
altitude the surface of the
basin is situated in
comparison to the sea
level(Zăvoianu I, 2006). In
Fig.11 Average altitude
I.Boldea, C. Sigmirean, D.-M.Buda
THE CHALLENGES OF COMMUNICATION. Contexts and Strategies in the World of Globalism
272 Section: Social Sciences
this case, the GIS software was used to automatically determine the average altitude.
The average altitudes of the river basins exceed 800 meters, specific to the mountainous
area. Their layout is closely related to the density of the hydrographic network. Thus, just like in
the case of density, the highest values of the average slopes are prevalent in the north-eastern
part of the massif, in the area of the volcanic caldera.
The morphometry of the hydrographic network
The length of the rivers is given by the distance (L), in km, measured along the water
flow from the spring to the the spill. The total length refers both to the main course and to its
tributaries.
𝐿 = 𝐿𝑝 + 𝑙𝑖
𝑛
𝑖=1
The density of the hydrographic network (D) conditions the capacity of rivers to collect
and drain rainwater as well as that of the underground waters. The density of the hydrographic
network is even more reduced if the terrain is harder and more resistant to erosion (granites,
gnose, etc.), while for lands such as clays it is enough to have a low flow to develop a drainage
network with a high density. Very permeable terrains (sands, gravel) determine a low density of
the hydrographic network due to rapid infiltration, while the practically impermeable terrain
determines a high value of its density (Scradaneanu, D., Gheorghe AI., 2007). It is calculated by
considering the ration between the total length of the watercourses and the surface of the river
basin:
𝐷 =Ʃ𝐿𝑐
𝐹𝑏𝑘𝑚/𝑘𝑚²
where: ΣLc is the sum of the lengths of all water courses and Fb is the surface of the river basin
Fig.12 Drainage density
I.Boldea, C. Sigmirean, D.-M.Buda
THE CHALLENGES OF COMMUNICATION. Contexts and Strategies in the World of Globalism
273 Section: Social Sciences
The density of the hydrographic network with a permanent flow regime (see annex) is a uniform
one, most of the basins being in the range of 1-1.3 km /km2
. The hydrographic basins with the
highest density are found in the western extremity of the massif (Budusel, Bridiceasa and
Pietroasa) and in the southeast of the analyzed area (Calimanel, Giristea, Dusa). The lowest
density is prevalent in the north of the Calimani Mountains. Values lower than 1 km / km2 are
found in the elongated basins, these basins having a predominant development near the main
course (Bucinisul, Bauca, Panulet). The average density is found on the largest surface of the
massif, being characteristic to the large and very large basins (Rastolita, Ilva, Lomas)
Conclusions
The morphometry of river basins is understood as a quantitative analysis of the relief
elements. This type of analysis allows the identification of important general characteristics in a
basin, especially when considering the relation between geomorphological characteristics and
hydrographic network. Thus, morphometric analysis plays an important role in hydrographic
studies as it allows a systematic assessment of the physical aspects of a basin and a better
understanding of resource dynamics.
Remote sensing and GIS tools are effective techniques in hydrographic network
extraction using digital terrain models (DEM). The results are closely related to DEM quality
and resolution, a quality that has grown in recent years, fact that enhances such studies. The
hydrological analysis carried out for the hydrographic basins located on the Calimani massif
confirms that the hydrographic basins have characteristics specific to the mountainous areas. The
vast majority of hydrographic networks in large basins have a predominantly dendritic,
homogeneous type, and contribute to understanding land parameters such as flow, infiltration
capacity, etc..
BIBLIOGRAPHY
1. Grudnicki F. & Ciornei I. (2007) Amenajarea Bazinelor Hidrografice Torentiale prin
Lucrari Specifice. Universitatea Stefan cel Mare. Suceava.
2. Horton RE (1932) Drainage basin characteristics Trans Am Geophysics Union.
3. Horton, R.E. (1945), Erosional Development of Streams and their Drainage Basins
"Hydro-Physical Approach to Quantitative Morphology", Bull. Geol. Soc. America 56
(1945)
4. Oyatayo Kehinde Taofik, Bello Innocent, Ndabula Christopher, Godwill Geofrey
Jidauna, Ademola Sunday James(2017) A Comparative Analysis of Drainage
Morphometry on Hydrologic Characteristics of Kereke and Ukoghor Basins on Flood
Vulnerability in Makurdi Town, Nigeria. Hydrology. Vol. 5, No. 3, 2017, pp. 32-40. doi:
10.11648/j.hyd.20170503.11
5. Pișotă I, Zaharia Liliana,(2003) Hidrologia uscatului, Bucureşti, Curs universitar,
6. Ritter, D.F., Kochel, R.C., and Miller, J.R., (1995), Process Geomorphology 3rd Ed.:
W.C. Brown Publishers, Dubuque, IA, 539 pp.
7. Scrădeanu , D., Gheorghe AI ., (2007), Hidrogeologie generală , Editura Universitătii
Bucuresti
8. Strahler, A.N. (1952), Quantitative Geomorphology of Erosional Landscapes, 19th
International Geological Congress, Algiers, Sec. 13, pp.341-359.
I.Boldea, C. Sigmirean, D.-M.Buda
THE CHALLENGES OF COMMUNICATION. Contexts and Strategies in the World of Globalism
274 Section: Social Sciences
9. Zăvoianu I,(2006) Hidrologie, Ediţia A IV-a, Ed. Fundaţiei România de mâine, Bucureşti,
2006,
10. Site ESRI - ArcGIS Online Help, http://desktop.arcgis.com/en/,
Annex
Den. bazin Fb Pc Pb Lb lb A.m
i
A.ma
x
A.med Pm Lc den β Kcu
m
Barzeta Mare 4.85 7.81 11.91
4.94 1.27 763 1478 1096.82
32.41
6.02 1.24
0.66
1.53
Bauca 8.5 10.34
13.99
5.61 2.56 1028 1991 1511.77
32.46
7.75 0.91
0.74
1.35
Bistra 92.16 34.03
42.97
13.36
10.02
568 1587 1134.07
31.18
112.94
1.23
0.79
1.26
Bistricioara 7.23 9.53 14.35
4.48 2.45 967 1464 1191.93
31.51
8.86 1.23
0.66
1.51
Bistrita 55.79 26.48
36.23
10.21
8.42 634 1581 1146.96
34.91
67.31 1.21
0.73
1.37
Borcurul 13.44 13 16.36
5.56 4.19 963 1489 1209.58
29.15
15.87 1.18
0.79
1.26
Bridiceasa 4.62 7.62 10.19
3.75 1.96 634 1122 849.26 29.42
7.16 1.55
0.75
1.34
Bucinisul 15.08 13.77
20.13
8.41 2.95 991 1850 1386.94
24.4 13.08 0.87
0.68
1.46
Budacul 40.84 22.66
30.05
9.69 6.03 759 1566 1232.11
28.86
51.06 1.25
0.75
1.33
Budusel 9.05 10.67
13.07
4.84 2.44 865 1494 1208.88
31.63
15.31 1.69
0.82
1.22
Calimanelul L 22.89 16.96
27.66
10.46
3.82 690 1333 999.94 24.79
28.96 1.27
0.61
1.63
Calimanelul T 13.7 13.1
2
21.3
4
8.42 2.36 702 1224 919.32 21.9
8
17.82 1.3 0.6
1
1.63
Dorna 45.78 23.99
28.9 9.61 6.39 1106 1931 1477.79
31.74
55.61 1.21
0.83
1.2
Dusa 6.12 8.77 12.35
4.76 1.86 662 1122 911.45 27.76
8.08 1.32
0.71
1.41
Fantanelul 12.1 12.3
3
18.8
7
5.28 4.63 614 1066 900.97 18.0
7
15.36 1.2
7
0.6
5
1.53
Galaoaia 34.89 20.94
27.72
10.73
4.54 541 1475 1071.46
29.71
40.23 1.15
0.76
1.32
Gioristea 15.28 13.86
18.74
5.84 3.92 654 1122 820.64 15.23
21.66 1.42
0.74
1.35
Ilva 125.7
2
39.7
5
54.5
2
19.4 11.3
8
605 2054 1225.4
6
34.8
3
151.0
2
1.2 0.7
3
1.37
Jingul
Niculesti
5 7.93 11.97
4.84 1.59 633 1169 947.46 30.09
5.9 1.18
0.66
1.51
Lomas 152.94
43.84
61.25
19.13
13.23
730 2010 1243.81
23.09
183.28
1.2 0.72
1.4
Mermezeu 12.5 12.5
3
19.5
3
7.94 2.35 665 1261 935.58 31 14.75 1.1
8
0.6
4
1.56
Neagra 92.55 34.1 41 13.94
9.57 1040 2055 1491 33.89
100.59
1.09
0.83
1.2
Neagra Calin 5.66 8.43 11.19
4.43 2.34 632 1155 968.89 31.03
6.64 1.17
0.75
1.33
Neagra II 45.89 24.0
2
37.7
7
12.2
8
7.95 1030 2013 1368.8
9
19.1
7
51.76 1.1
3
0.6
4
1.57
Negrisoara 10.95 11.73
14.18
4.28 4.02 1166 1844 1505.39
34.51
10.41 0.95
0.83
1.21
I.Boldea, C. Sigmirean, D.-M.Buda
THE CHALLENGES OF COMMUNICATION. Contexts and Strategies in the World of Globalism
275 Section: Social Sciences
Panulet 8.51 10.3
4
14.7
8
5.29 2.83 1004 1587 1410.1
4
18.9
4
8.59 1.0
1
0.7 1.43
Paraul cu
Pesti
7.61 9.78 12.85
5.16 2.08 1034 1742 1402.34
33.67
9.19 1.21
0.76
1.31
Paraul Negru 10.61 11.55
15.45
5 3.87 983 1534 1302.7 21.92
11.82 1.11
0.75
1.34
Paraul Rusilor 3 6.14 7.9 3.12 1.71 979 1295 1126.81
19.6 3.78 1.26
0.78
1.29
Pietroasa 19.1 15.5 18.16
6.24 4.49 659 1496 1014.62
32.37
25.19 1.32
0.85
1.17
Porcul 4.29 7.34 11.24
4.79 1.53 672 1225 998.94 29.52
5.28 1.23
0.65
1.53
Rastolita 159.97
44.84
61.78
17.76
15.6 562 1969 1176.99
32.76
196.67
1.23
0.73
1.38
Runcul 3.28 6.42 9.6 3.85 1.28 785 916 854.45 12.04
3.94 1.2 0.67
1.5
Taietura 5.51 8.32 10.2 4.03 2.36 1034 1671 1323.3 26.65
6.22 1.13
0.82
1.23
Tarcani 2.32 5.4 9.9 4.4 0.97 1041 1711 1347.23
22.31
2.93 1.26
0.55
1.83
Tilimiul de
Sus
7.33 9.6 12.37
3.26 3.1 999 1877 1315.7 32.63
7.25 0.99
0.78
1.29
Tomnaticul 27.2 18.49
32.21
10.58
4.27 1033 1992 1439.22
16.42
30.22 1.11
0.57
1.74
Visa 7.66 9.81 16.42
6.62 2.16 595 1303 987.99 30.13
7.77 1.02
0.6 1.67
Vorova 14.08 13.3 15.77
5.18 4.34 1166 1862 1510.42
31.28
15.27 1.08
0.84
1.19
Zebrac 22.92 16.97
24.01
8.8 3.87 651 1480 977.32 30.77
25.81 1.13
0.71
1.41
Fb - basin surface, Pc – circle perimeter, Pb - basin perimeter, Lb - basin length, lb - basin width, A.min -
minimum altitude, A.max - maximum altitude, A.med - average altitude, Pm – average slope, Lc - Length
of watercourses, den - density, β - circularity coefficient, Kcum – the development coefficient of the
watershed