Definition of GIS
The definition of GIS is a system whose functions are collection, regulation, management, storage and presentation of all types of data (information) related to geography.
GIS has subsystems (work stages), namely:
a. Input (input). GIS data comes from maps, tables, aerial photographs, satellite images, and the results of field surveys.
b. Data processing and storage (process) is data storage that allows it to be recalled or corrected quickly and accurately where data is stored on a computer. There are 3 (three) data analyzes, including:
- Width analysis. For example: producing a riverbank area with a certain width.
- Arithmetic addition analysis. This analysis can handle maps with classification
- Line and plane analysis.
There are 2 data that are processed in GIG, namely:
- Spatial/spatial/graphic data is data that refers to space locations or other places on the Earth’s surface. Spatial data in the following form.
- Descriptive data / attribute data / tabular data, namely data that is in spatial / regional / location. Descriptive data in the form of qualitative (symbol) or quantitative (number of levels) in a graph or map.
c. Presentation (output) namely the presentation of some / all data and the results of data manipulation can be in the form of tables, submit electronic maps (digital), graphics, and others.
- Software (software), includes hundreds of program modules including Autocad, ARC/info, Erdas, and Ilwis, Idris version 4.1 (for DOS) and Mapinfo version 4.0 (for windows).
- Hardware (hardware), includes computers (PCs), Desktop, workstations, multiuser hosts, hard disks, RAM, mouse, digitizer, printer, plotter, and scanner.
- Geographical data and information, GIS can collect and store the required data and information either directly or indirectly by importing it from other GIS software or directly by digitizing spatial data from maps and inserting attribute data from tables and report using keyboard.
- ManagementA GIS project will be successful if it is managed properly and carried out by people who have the right expertise.
Utilization of GIS
- Selection of transmigration locations so that the selected area is truly suitable for population settlement.
- Planning the right time for population relocation, according to the conditions of the area to be visited.
- Urban planning and data related to spatial planning.
- Monitoring of environmental pollution.
Marine area planning and monitoring
- Search for fish in the sea and other marine products.
- Monitoring of shoreline and abrasion.
- Monitoring of marine processes such as uplift, currents, and intrusion of seawater to land.
Monitoring of underdeveloped village inpres program (IDT)
- Information on village potential in the form of roads, transportation, livelihoods, houses, land ownership rights, health facilities, educational facilities, markets, and communication advice.
- Population information is related to population density, distribution, growth, and composition.
- Environmental information related to water sources, lighting of places of worship, waste disposal, and latrines/MCK.
Agriculture and forestry
- Inventory of food crops, related to information on the area of land for food crops, the area of damaged land, and the area of better land.
- Land use monitoring.
- Inventory of plantation crops/agricultural crops.
- Forest inventory and monitoring needed for reforestation planning, forest expansion, and forest destruction prevention.
- Critical land inventory, changes in the number of critical land each year, and soil fertility.
Natural resource mapping
- Land use mapping
- Green land mapping is very necessary for agricultural land.
- Mapping of tidal areas to be developed as agricultural areas and other interests.
- Geological mapping used for exploration and natural disaster management purposes.
Natural disaster monitoring
Inventory, evaluate, and monitor natural disasters such as volcanic eruptions, earthquakes, forest fires, pest attacks, and others.
GIS operations are divided into two, namely modern (computerized) and conventional (manual). Modern GIS operation uses a computer so that the data is in digital form. Conventional GIS usually consist of several data elements including maps, transparency material sheets for overlapping, aerial photographs, field photographs, as well as statistical reports and field surveys. One of the common procedures performed in conventional GIS is squeezing (expanse) multiple maps to find information about a particular area.