BASICS OF PRECISION AGRICULTURE (PA)

Transcription

1 BASICS OF PRECISION AGRICULTURE (PA) specific production on particular place specific production, from foot to foot... Same sense: data collection and decision making for small pieces of the field. Particular field pieces Usual average data for whole field (yield, nitrogen content, fertilizing rate... - per ha) PP principle identifying of particular part of the field for data collection and analysis precise and reliable decision making Homogenous parts with significant differences and parts of the uniform network Decisions and data for one part don t apply to another parts of the same field. 10/15/2013 1

2 Particular parts of the fields 10/15/2013 2

3 Spatial variability - driving force of precision agriculture Specific procedures for each part of the field, not applicable for the other parts. Soil type, slope, porosity, surface layer depth, sand content, nutrients content, soil compaction, acidity.... Different attributes (characteristics) Map of ph values: lighter parts present acid (lower) ph (under 7.0) and vice versa 10/15/2013 3

4 Spatially based questions for decision making: Farming with conventional or zero soil tillage what is more profitable? Which crop will give maximum yield on particular soil type? Where will soil compaction affect the yield and profit? Which crops should be replaced to increase productivity? Example: Non efficient application of constant mineral fertilizers rate variability causes over/under fertilizing. Application of variable rates instead specific fertilizing rate on specific part of the field. 10/15/2013 4

5 Technology Technical devices on the tractor - GPS, monitors, controlers, communication devices... 10/15/2013 5

6 Benefits Environment Reduced and variable input costs. Procedures that decrease environmental pollution. Economy More profit, intensive financial turnover and less expenses, by higher yields and lower inputs for chemicals and fertilizers. Analysis of machinery efficiency fuel, lubricants, maintenance Analysis of profitability of particular crops Agriculture demands balance between environment and economy. Sustainability of agriculture, natural resources, economy 10/15/2013 6

7 Tools of precision agriculture Global positioning system (GPS) Geo-informational system (GIS) Remote Sensing (RS) Intelligent Devices and Implements (IDI) Computers 10/15/2013 7

8 Global Positioning System (GPS) GPS system positioning based on 24 NAVSTAR satellites in orbit around the Earth and GPS receivers on the ground. Distance (R) of each satellite is calculated according to the time and signal velocity, which defines 4 values: X, Y, Z 3 spatial coordinates for 3-dimensional spatial positioning and time T. 10/15/2013 8

9 GPS error and correction defines the accuracy of positioning Accuracy m (even 100 m) at autonomous GPS (no correction), Accuracy under 25 mm with differentially corrected GPS-signal. Differential correction of positioning Based on the other GPS-receiver - BASE at known position. Any difference between the real and calculated latitude and longitude is recognized as differential error. 10/15/2013 9

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11 Differential correction 10/15/

12 Remote sensing Remote sensing is the acquisition of information about an object or phenomenon without making physical contact with the object. Remote sensing relies on wave length of reflected EM radiation emitted from aircraft or satellites. 10/15/

13 10/15/2013 Spectral signature 13

14 BASIC PROCEDURES Data collection Yield monitoring and recording (automatic device on the harvester) Soil sampling Surveillance Data analysis Application 10/15/

15 MAPS BASICS You are nowhere without geography " Coordinate systems Rows and columns in ordinary table. Combination of the letter and number (coordinates) is exact address/position of the cell in the table. 10/15/

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17 Geographic Coordinate System - GCS Imagined network over the Earth surface, consisted of latitudes and longitudes. Latitudes rows of GCS horizontal circles parallel with Equator. North and south latitude distance from Equator zero latitude. Values (angle measures): 0 (Equator) 90 (North pole) -90 (South pole) Longitudes columns of GCS half circles from pole to pole. East and west longitude distance from Greenwich/zero meridian Values (angle measures): 0 (Greenwich) 180 (to east) -180 (to west) 10/15/

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19 Formats of GCS coordinates DD format - decimal degrees degrees north latitude degrees west longitude DM format - degrees minutes degrees 33.6 minutes north latitude degrees 28.8 minutes west longitude DMS format - degrees minutes seconds degrees 33 minutes i 36 seconds north latitude degrees 28 minutes 48 seconds west longitude 10/15/

20 Scale The ratio of a distance on the map to the corresponding distance on the ground. Example: 1: cm at the map presents cm in field. Scale deals with details! Large scale map (up to 1: ) small region with many details Small scale map (1: and more) large region with less details. 10/15/

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22 Types op maps Reference map Some basic objects and features in Serbia. (larger cities, roads, rivers) Thematic map Presents values of some attribute. (number of men per 1000 women, by municipality) 10/15/

23 GIS (Geographic Informational System) Map and data base two components in GIS. Map and data base are functionally connected. Each poligon on the map has its row in the data base table. The rows contains the attributes of each poligon. Each field (column) in the data base table presents one attribute. SCSS0IL5 SOILNAME LCC PRIMELND LEAGFMLND CSR CORNYLD SOYBNYLD OATYLD WHEATYLD IA0048 KENYON 2E P P IA0071 COLO 2W P5 P IA0071 COLO 2W P5 P IA0048 KENYON 3E S P XS0381 KLINGER-MAXFIELD SICL 2W P2 P IA0066 DINSDALE 2E P P /15/ IA0066 DINSDALE 3E S P

24 GEOGRAPHIC INFORMATIONAL SYSTEM (GIS) What is GIS? Too simple electronic map. Exactly system of: computer, software, personnel, peripheral equipment and data. GIS system enables user to identify complex spatial relationships 10/15/

25 GIS map Set of overlaid layers. Each layer is digital presentation of one object - feature. One layer can contain thousands of features. Layers can be imagined as clean transparent sheets, overlaid one over another. 10/15/

26 Layers form a map 10/15/

27 GIS data base Each layer in the map has its own data base FID Shape WPT_NUMBERR WPT_NAME LATITUDE LONGITUDE DATE PHS98 BPHS98 OMS98 PS9S HKS98 CAS98 MGS98 CECS98 0 Point /5/ Point /5/ Point /5/ Point /5/ Point /5/ Point /5/ Point /5/ Point /5/ Point /5/ Each row in the table presents one feature in the map. Each column (field) in the table presents one attribute in the map. Attribute values of each feature are functionally connected with its feature in the map. GIS data base stores, organizes, searches and analyzes those data. 10/15/

28 DATA STRUCTURE Data format determines how will the data (attributes and locations) will be stored and presented in GIS. Attribute data are characteristics of the feature: tree diameter, number of grains in the corn cob ph value of the soil sample. Location data are coordinates for precise geographic positioning of that feature on the map. Base of those data is used for their storage, but in which format are those data presented? Vector and raster are two usual and well known data formats for presenting and storage. 10/15/

29 Vector data Vector layer contains: - points, - lines and - polygons. Any feature in the map can be identified by one of those three vector shapes. Object is physical entity in real world. Feature is vector presentation of of that entity on the map (point, line, polygon). 10/15/

30 Sources of vector data GPS - Global Positioning System Digitalization of paper maps Vector data from internet 10/15/

31 Raster data Rasters formats store the data in the mesh series of rows and collumns In there intersections are formed mesh cells. Each cell has location data and only one attribute value. Each value or interval of values is presented and visualized by different color data visualization. Mesh covers the whole surface of the area. vector raster 10/15/

32 Digital elevation model example of a raster mesh Attribute value of each mesh cell is altitude. 10/15/

33 Example from Google Earth: error in digitalization of the raster image of river banks and island in vector format lines Left layers list. Active layers: - Primary Database (raster) - Roads (vector lines) - Water Bodies (vector - lines) 10/15/