Modeling and management of run off erosion Naxos, 5 September 2016 Dr. Dr. MSc Evelpidou Niki As. Professor http://evelpidou.geol.uoa.gr
GEOGRAPIC INFORMATION SYSTEMS (G.I.S.)
What are the G.I.S.? Software that utilizes the capabilities of computers: Storing Presentation Data management Data analysis Direct or indirect geographical distribution G.I.S
Raster & vector data Basic characteristics Raster Digital images (maps, aerial photos, satellite images or even photographs) Vector Digitized data (points, lines, surfaces)
Coordinates & Scale Basic characteristics O L The scale of a map in GIS has no upper or lower bound. It is restrained by the scale of the primary data.
Basic principles of operation concepts Information layers Points Lines Areas Raster 3D relief The correct order of information layers ensures that no object of the map will be covered by others.
Geographic search Finding the residents within a radius of 5 Km from a square Finding the drillings within a distance of 9 Km from the shore Finding the drillings (of a depth greater than 15 m), within a distance of 9 Km from the shore building blocks based on a percentage of building or population density, or... & classification of these Selection of locations that are located in erodible rocks or within a land use type A, or Measurements General characteristics Management of objects through coordinates Distances (a village from the shoreline or from another point) Length (road network section, fault,.) Perimeter (of a settlement, ) Area (land use, geological formations, ) Direct transfer and presentation of data in different metric or projection systems
Visualization of data General characteristics Browsers Through known software (e.g. excel) Thematics Through known software (e.g. VBasic)
Spatial analysis Thematic cartography Methods of Thematic Cartography Ranges Bar charts Pie charts Graduated symbols Dot density Individual values Grid
Thematic cartography Data analysis
Find, Search & Find selections Spatial analysis Basic operations of analysis / find objects Find data based on descriptive data With precise wording of record Without precise wording of record Ability to find data based on spatial information Identifying selected object on the map or database
Spatial analysis SQL search SQL Search Combining more than one information layer Combining descriptive and spatial information Setting multiple criteria Setting rules for the form of response (e.g. order of display)
Spatial analysis Modifying objects Split objects based on other objects Split Erase Erase outside
Creation of buffer zones Spatial analysis 2 2 ) )
Spatial analysis Updating a database Updating the database based on: " " " " " " " ( 0 1 2 Km " " " " " " " " " " " " " " " " """ " " "" " " " " " " " " " "" " " " " " " " " Geographic relation " " " "
Updating columns of a database Quantitative Analysis Updating the database Through another database With geographic data (area, length, geographic coordinates, etc.)
Quantitative Analysis Creating graphs Statistical analysis of data imported or produced in a GIS
Quantitative Analysis SQL search The SQL search provides a subset of the existing data In these we can define: The way of organization of records. The way of data combination.
EXAMPLES OF G.I.S. APPLICATION IN SECTORS OF SOCIETY
ΕΦΕΣΣΟΥ ΕΦΕΣΣΟΥ Examples of G.I.S. application in sectors of society Land uses (in an urban area) Ν 50 Γ. ΠΑΠΑΝΔΡΕΟΥ 17 ΩΠΗΣ road network Σχολείο building blocks Δημοτικό Νεκροταφείο 1ο etc. Νηπ/γείο Σχολείο ΠΛΑΤΕΙΑ ΚΩΝΣΤΑΝΤΙΝΟΥΠΟΛΕΩΣ Γ. ΠΑΠΑΝΔΡΕΟΥ 210 Σχολείο Σχολικά κτίρια ΠΛΑΤΕΙΑ ΚΩΝΣΤΑΝΤΙΝΟΥΠΟΛΕΩΣ ΔΗΜΟΣ Οικοδομικά τετράγωνανεασ ΦΙΛΑΔΕΛΦΕΙΑΣ ΠΑΠΑΦΛΕΣΣΑ ΒΟΥΡΝΟΒΑ ΝΕΑΠΟΛΕΩΣ ΑΝΔΡΙΑΝΟΥ ΠΡΕΒΕΖΗΣ Δημοτικό Νεκροταφείο ΛΕΣΒΟΥ ΚΟΙΜΗΣΕΩΣ ΘΕΟΤΟΚΟΥ ΥΨΗΛΑΝΤΟΥ Δ. ΘΕΟΤΟΚΟΠΟΥΛΟΥ ΑΝΘΕΩΝ ΣΟΛΩΜΟΥ ΘΕΜ. ΣΟΦΟΥΛΗ 209 ΜΗΔΕΙΑΣ ΜΑΓΝΗΣΙΑΣ ΔΙΓΕΝΗ 264 219 189 265 ΕΘΝΙΚΗ ΟΔΟΣ ΑΘΗΝΩΝ - ΛΑΜΙΑΣ ΜΗΔΕΙΑΣ ΣΑΡΑΝΤΑ ΕΚΚΛΗΣΙΩΝ ΑΓ. ΤΡΙΑΔΟΣ ΕΠΤΑΛΟΦΟΥ ΣΟΛΩΜΟΥ ΚΥΖΙΚΟΥ ΚΡΕΣΤΑΙΝΗΣ ΘΕΜ. ΣΟΦΟΥΛΗ ΔΙΓΕΝΗ ΣΟΛΩΜΟΥ ΑΝΤΙΓΟΝΗΣ ΓΡ. ΛΑΜΠΡΑΚΗ ΦΙΛΙΠΠΟΥ ΔΡΑΜΑΣ Π. ΜΕΛΑ ΧΡΥΣΟΣΤΟΜΟΥ ΣΜΥΡΝΗΣ ΠΑΠΑΔΙΑΜΑΝΤΗ ΞΕΝΟΠΟΥΛΟΥ ΚΙΡΚΗΣ ΑΝΑΞΑΓΟΡΑ ΦΛΕΜΙΓΚ Σχολικά κτίρια ΙΑΣΩΝΙΔΗ ΣΤΡΑΤ. ΠΑΠΑΓΟΥ ΙΩΝΙΑΣ 185 Δημοτικό γυμναστήριο Ζωολογικός κήπος ΑΝΑΞΑΓΟΡΑ ΔΩΔΕΚΑΝΗΣΟΥ 205 186 206 191 Δημοτικό γυμναστήριο 183 176 180 175 197 196 174 166 193 Μνημείο/Μουσείο Μικρασιατών 168 192 167 199 198 194 169 241 Δημοτικό Νεκροταφείο 242 161 165 160 243 Πνευματικό κέντρο 244 164 245 157 148 156 125 154 155 142 146 37 Σχολή Μετεωρολογικός σταθμός 124 143 Αστυνομικών 123 156 141 30 Γκαράζ 248 121 117 120 118 119 116 110 Σχολή Αστυνομικών 111 134 112 115 113 53 114 50 131 38 39 52α Πεζόδρομος 52 40 35 41 51α 36 37 30 88 ΑΕΚ 51 87 34 31 33α 17 Κέντρο διασκέδασης 33 18 29 89 16 86 15 14 ΑΕΚ 98 297 85 48 449α Μονοπάτι 49 43 11 75 32 10 449β 80 7 73 74 77 81 9 8 82 448ε 448γ 83 72 448η Εκτός σχεδίου περιοχή 3 71 91 92 94 5 76 448δ 96 25 97 2 68 Α 1 Β 18 102 95 100 99 67 Δ 98 27 19 103 24 64 104 105 29 62 0 106 21 23 Σχολείο 22 56 61α 55 Kallithea: Building blocks & Road network. The direction of ΚΟΙΜΗΣΕΩΣ ΘΕΟΤΟΚΟΥ 38 uses of building blocks 36 ΤΡΑΠΕΖΟΥΝΤΟΣ ΟΤΟΚΟΥ ΣΙΝΩΠΗΣ ΤΡΑΛΛΕΩΝ Ζωολογικός κήπος ΤΡΑΠΕΖΟΥΝΤΟΣ Μετεωρολογικός σταθμός ΚΑΙΣΑΡΙΑΣ Κένταυρος Σχολείο 39 ΤΥΑΝΩΝ ΥΠΟΜΝΗΜΑ ----- ΚΑΙΣΑΡΙΑΣ Ποτάμι uses - ownership of buildings Χώροι πρασίνου Παιδική χαρά ` Ζωολογικός κήπος Σχολείο Γήπεδο ΕΦΕΣΣΟΥ ΝΙΓΔΗΣ ΕΦΕΣΣΟΥ ΕΦΕΣΣΟΥ ΜΟΥΔΑΝΙΩΝ ΒΡΥΟΥΛΩΝ ΤΥΑΝΩΝ ΚΑΒΑΔΕΛΑ 40 ΝΙΚΟΜΗΔΕΙΑΣ Nea Filadelfia: Building travel blocks of - vehicles Land Uses is noted. ΤΥΑΝΩΝ ΖΑΪΜΗ 256 213 210 ΝΙΚΑΙΑΣ ΔΕΚΕΛΙΑΣ ΠΑΝΟΡΜΟΥ 257 258 218 216 261 ΒΑΣ. ΑΛΕΞΑΝΔΡΟΥ ΜΕΡΣΙΝΗΣ ΝΙΚΑΙΑΣ ΦΩΚΩΝ ΙΚΟΝΙΟΥ ΝΙΚΑΙΑΣ 233 232 231 ΑΧΑΪΑΣ 234 ΘΕΣΠΡΩΤΙΑΣ 271 ΛΥΚΟΥΡΓΟΥ 502 ΦΛΕΜΙΓΚ ΑΓ. ΜΑΡΙΝΑ ΧΑΝΙΩΝ 243β 239 ΣΟΥΛΙΟΥ ΡΙΜΙΝΙ 240 ΣΕΡΡΩΝ ΜΩΡΑΪΤΙΝΗ 250 240 252 ΚΙΛΚΗΣ ΑΜΦΙΣΣΗΣ ΚΑΒΑΛΑΣ ΣΚΡΑ ΚΥΜΗΣ 349 ΛΑΧΑΝΑ Μετεωρολογικός σταθμός 328 329 255 254 Κένταυρος Σχολείο 351 352 283 354 279 356 281 ΚΑΡΔΙΤΣΗΣ ΧΙΟΥ 348 Σχολή Αστυνομικών ( ΑΡΤΗΣ 357 ΑΜΜΟΧΩΣΤΟΥ ΡΟΔΟΥ ΒΕΝΙΖΕΛΟΥ 0 0.1 0.2 χιλιόμετρα
Examples of G.I.S. application in sectors of society Land uses (in an urban area) Attica / Panepistimioupoli
Examples of G.I.S. application in sectors of society Land uses (in an urban area) Acharnai / Attica
Examples of G.I.S. application in sectors of society Infrastructure networks Water supply Sewage network Irrigation network etc. Φυσικογεωγραφικά / Περιβαλλοντικά χαρακτηριστικά Κύριος αγωγός νερού Αγωγός αρδευτικού δικτύου Υδροληψία ) Δεξαμενή 4 Αντλιοστάσιο Διατομές Διατομή φ 63 Διατομή φ 90 ) ) Διατομή φ 110 Διατομή φ 140 Διατομή φ 160 ) Διατομή φ 200 Ανθρωπογενή χαρακτηριστικά ) Όρια Δήμων Χρήσεις Γης Δάσος Φρύγανα Υδρόβια βλάστηση Αμμώδης παραλία 4 ) Σταθεροποιημένες θίνες Ελαιώνες Καλλιέργειες Λίμνη Οικισμός
Examples of G.I.S. application in sectors of society Environmental characteristics 700 Διβαράτα 822 451 ' 131 Καραβόμυλος 00 Αγία Ευφημία 548 397 900 1,0 α Δυ νατή 400 800 642 401 Όρμ.
Examples of G.I.S. application in sectors of society Geological Geomorphological characteristics
Examples of G.I.S. application in sectors of society Three-dimensional maps
Examples of G.I.S. application in sectors of society Distribution of fieldwork sites
Examples of G.I.S. application in sectors of society Monitoring of flood events Density Frequency Ranges Ranges 31 to 331 (219) Basins 5,4 to by 19 Class (228) Drainage network analysis 19 to 31 (218) 4,1 to 5,4 (235) 1 12 (685) to 19 (215) 3,2 to 4,1 (181) 2 (160) 1 to 12 (249) 0,5 to 3,2 (257) 3 (39) 4 (13) 0 5 (2) 1.5 6 (1) 3 3 ydrological balance analysis Automatic water level monitoring and notification of potential flood event 0 1.5 Km Km Definition of risk zones 0 1.5 3 Economic damage * assessment * after flood events based on land use Km Creation of scenarios * Classification of drainage network per class Frequency Drainage density of drainage network
Examples of G.I.S. application in sectors of society Analysis of visibility areas of a pointof flood events Examples: From which points of the island, a selected area is visible (e.g. a landfill, a quarry, etc.). To mark segments along a route, where the point of arrival is visible. Etc. Ανάγλυφο Ν.Νάξου (m) Χάρτης ορατότητας από το σημείο Α
EROSION RISK MODEL
ow to do that? What do we expect from a model? EROSION RISK MODEL LET S BUILD ONE ow to start? Can I do it? Sounds difficult task!
Calculation of erosion risk The basic stages of methodology For the creation of an erosion risk map, a series of stages are followed: Definition of parameters affecting erosion risk Data collection Definition of input & output variables Calculation of parameters Establishment of logical rules amongst variables Application of logical rules Analysis and presentation of results
Calculation of erosion risk The basic stages of methodology For the creation of an erosion risk map, a series of stages are followed: Definition of parameters affecting erosion risk Data collection Definition of input & output variables Calculation of parameters Establishment of logical rules amongst variables Application of logical rules Analysis and presentation of results Sounds still complicated!
Ok! Let s Define the parameters affecting erosion risk
Calculation of erosion risk The basic stages of methodology Data collection: Stereoscopic observation of aerial photos Field work Data collection from maps and literature Analysis of geological characteristics Analysis of tectonic characteristics Analysis of topographic characteristics Analysis of hydrographic characteristics Analysis of land uses
Calculation of erosion risk The basic stages of methodology Define the shape and size of the smallest geographic entity, in which erosion risk will be calculated.
Calculation of variables Definition of shape and size of smallest geographic entity e.g. Grid: For the calculation of variables, a grid is created, of specific dimensions e.g. 500x500 m, with the exception of those adjacent to the coastline. The dimensions of cells are defined by their shape. Of course, the size of cells can be modified depending on the accuracy of primary data. Application
Calculation of erosion risk The basic stages of methodology Input variables, e.g. Vulnerability Morphological slope ydrographic density
Calculation of erosion risk The basic stages of methodology Development of primary data
Application Primary data Next step is the creation of primary information layers Vulnerability: Vulnerability is calculated by classifying rocks based on their resistance to erosion. The shape and size of rock grains define the permeability of the rock formation. This factor controls the quantity of surface flowing water. Finally, the presence and type of vegetation works as a negative factor in vulnerability.
Application Primary data The first step is the creation of primary information layers Vulnerability: In order to calculate vulnerability, we need the following layers: Geological formations, expresses as polygons, whose database will include lithology, age and area. Tectonic lines, expresses as polylines, whose database will include the type (fault, overthrust, etc.) and length. Land cover, expresses as polygons, whose database will include the type of soil, the thickness and the area. Land uses, expresses as polygons, whose database will include the type of land use and the area. Climatological data of the area are also necessary.
Calculation of variables Application Vulnerability: The database of the grid should be updated with: The percentage of area of each geological formation, The length and number of tectonic lines, The percentage of area of each land cover and The percentage of area of each land use. Based on the aforementioned and the climatic data, it is calculated how vulnerable each cell is in relation to its neighboring. Through successive selections, the formations with the maximum and minimum vulnerability are found. The formation with maximum vulnerability receives value 1, while the formation with minimum vulnerability receives value 0, and the rest receive intermediate values.
Application Primary data Slope: Apart from the value of morphological slope, other important factors are its shape, its direction and its length. It is clear that the value of slope is a defining factor for the intensity of erosion.
Application Primary data Morphological Slopes: Morphological slopes are calculated based on topography, therefore the information layer of contours is necessary. Contours, are expressed as polylines, whose database will include the altitude and length.
Application Primary data Drainage density: It is directly related with the quantity of surface water and the infiltration capability. In general, the drainage density is high on the cells that include vulnerable and impermeable formations and low in the cells that include massive, permeable formations. It is also proven that drainage density is increased in proportion to the altitude and the average slope of the cell.
Application Primary data Drainage density: Drainage density is secondarily calculated by the relief and the drainage network, therefore the information layers of drainage basins and network are necessary. Drainage basins, expresses as surfaces, whose database will include the number of branches, the total length of branches and the area of the basin. Drainage network, expressed as polylines, whose database will include the length and class.
Calculation of variables Calculation of variables Application
Calculation of erosion risk The basic stages of methodology The calculation of variables is relatively easy task because GIS is doing most of the job. Variables are calculated within one grid for each cell, meaning for each cell a triad of variables exists, which is used for the production of different thematic maps.
Calculation of erosion risk The basic stages of methodology In thematic maps, each variable is classified in three categories Low, Medium and igh, which constitute the input variables.
Application Input variables The normalized values of the 3 variables are divided in three ranges, which are presented in thematic maps. Vulnerability is divided with the method Equal Ranges in three categories Low, Medium and igh. Respectively, morphological slope is divided, while drainage density is divided with the method Equal Values.
Calculation of erosion risk The basic stages of methodology Subsequently, the appropriate logical rules are adopted for the calculation of the output variable, which are the different degrees of erosion risk that is classified as Very low, Low, Medium and igh.
Application Logical rules and output variable The adoption and application of rules follows The application of logical rules transforms the input variables to the output variable, which is the erosion risk. Their application is accomplished through successive selections and updates. The output variables are presented also through a thematic map.
Vulnerability Slope Drainage Erosion Density If Διαβρωτικότητα Is 0.8 igh - 1 & Κλίση Is igh 0.6-1 Then Risk Is Index Vulnerability Slope ydrographic 0.59-0.8 0.4-0.6 0.426-1 0.38-0.59 0.2-0.4 0.255-0.426 0.17-0.38 0-0.2 0.083-0.255 Erosion Mediu Υδρο/φική 0-0.083 If Διαβρωτικότητα Is igh & Κλίση Is & Is igh Then Risk Is m Πυκνότητα density Index igh igh Erosion risk If Διαβρωτικότητα Is igh & Κλίση Is Low Then Erosion Risk Index Is Medium If Διαβρωτικότητα Is Mediu m & Κλίση Is igh Then Erosion Risk Index Is Medium If Διαβρωτικότητα Is 0 ( Mediu m 1.5 3 Km & Κλίση Is Mediu m &( 0 Υδρο/φική Πυκνότητα 1.5 3 Km Is igh Then Erosion Risk Index 1.5 3 0 ( Km Is Medium If Διαβρωτικότητα Is Mediu & Κλίση Is Low Erosion Υδρο/φική & Risk m Πυκνότητα igh Is igh Then Medium Low If Διαβρωτικότητα Is Low & Κλίση Is Low Very Low Then Erosion Risk Index Erosion Risk Index Is Is Low Very Low 0 ( 1.5 3 Km
Summary E R O S I O N R I S K
Modeling and management of run off erosion Thank you for your attention! Dr. Dr. MSc Evelpidou Niki As. Professor http://evelpidou.geol.uoa.gr