Free Geography Tools

Part three of this series (part one, part two).

Natural Resources Database (NRDB)

Type: Freeware, open-source

Platform: Windows

Last update: 2007

Personal experience: Minimal

Description

NRDB is a free GIS tool for developing and distributing environmental databases. Its aim is to provide people in developing countries with a powerful yet simple tool to assist in the managing of their own resources.

Database

The Natural Resources Database is a spatial database. As well as storing data of type text or numbers you can also store point, polyline or polygon data.

The data structure of NRDB is hierarchical. This means that, for example, you can represent the administrative structure for your project area and calculate statistics based on this.

NRDB is also a time-series database, all data has a date associated with it. You can therefore observe changes over time in the data.

All data for the NRDB is stored in a single database file which can be redistributed with the software.

The database structure consists of features and attributes. You define these in the Data Dictionary. You can define a structure that meets the needs of your project. NRDB is therefore is applicable to a wide range of environmental / socio-economic projects in developing countries.

Maps

Maps consist of layers. Each layer contains a spatial attribute, e.g. an administrative boundary or the location of a village, and a text or numeric attribute to be used as a label e.g. the name of the village, or the number of households above the poverty threshold.

You can create thematic maps whereby the way the layer is displayed is determined by the values. For example you can make the fill color or symbol size dependent on the value or you can use different colors to indicate houses with and without access to safe water.

You can also change other aspects of the appearance such as the type of the symbol and the positioning of labels.

NRDB includes automatic layout for printing of maps.

NRDB supports UTM and other transverse Mercator projections. UTM projections can be selected simply by clicking on the world map.

Queries

As well as simple selection of features and attributes to display on maps, graphs and reports you can also use queries. These give you more control over what is displayed. With queries you can apply conditions, e.g. only select data for 2002 or display only households that are not formal settlers and are living in makeshift housing.

Queries can also be used for calculating statistics. You can for example count the number of households below the poverty threshold by municipality. You could also normalize this by dividing it by the number of households in each municipality.

In the same way that you can add layers to maps, by selecting values or using queries, you can also produce reports.

You can also output data as histograms, time-series graphs and pie charts.

Digitizing, Import and Export

Data can be encoded directly into the NRDB software. You can also encode data into a spreadsheet and then import it into the NRDB software.

Spatial data can be imported from shapefiles or text files. NRDB also includes a utility for georeferencing image files scanned from paper maps. You can then digitize directly using the NRDB software.

You can export map layers to shape files.

ObjectLand

Type: Commercial software; free for evaluation/educational uses (with watermark)

Platform: Windows

Last update: 2008

Personal experience: None

From Russia.

GIS ObjectLand is a universal Geographic Information System for Windows.

Key capabilities:

• vector-raster maps;
• multiuser data editing;
• import and export for MIF/MID (MapInfo), SHP (ArcView), DXF (AutoCAD), DBF (dBASE), CSV;
• setting access permissions to data for different categories of users;
• using tables of native DBMS or external DBMS (via ODBC);
• automation COM interfaces for user applications.

OrbisGIS

Type: Freeware, open-source

Platform: Windows, Linux

Last update: 2007

Personal experience: None

OrbisGIS is a Geographical Information System (GIS) dedicate to the scientific modeling and simulation. OrbisGIS is develop at IRSTV (Research Institute on Urban Sciences and Technics, CNRS/FR-2488), in the context of the Urban Data Federative Research Project. This project has to do with Urban GIS : tools and methods for the spatial analysis of the urban environment.

Three main axes structure this scientific framework :

• data acquisition techniques (remote sensing, modeling and simulation, site enquiries…),
• spatial data processing and representation (storage, modeling, multiscale 3D+t simulations),
• geographic data sharing.

OrbisGIS is a part of a more global Spatial Data Infrastructure. It is a mandatory component to anyone who needs to process spatial data(create, update, process and model) or visualize them. Based on robust and well-known libraries of the public domain such as JTS (Java Topology Suite) or ImageJ, it provide the ability to join or visualize 2D vector and/or raster data. Those both data types may be stored in a local or remote DataBase Management System or a flat file…

Structure and data model

In OrbisGIS, spatial data are stored in layers. This abstraction has a typical tabular structure that uses rows to store each of the elements of the data source. This structure is close to the JDBC standard, and, as an example, to the storage format of the spatial data used in PostgreSQL/PostGIS.
Concerning rasters, the storage format is the one that is used by ImageJ.

Data access

Data access are realized through two libraries :

• GDMS (Generic Data-sources Management System) is a semantic layer that has the ability to address and manipulate heterogeneous data. It provides both an API and an extended Spatial SQL,
• GRAP (GeoRAster Processing) is an abstract layer that provides the ability to process raster data independently from the storage format and from scale. It is a layer that relies on ImageJ.

Visit the GDMS and GRAP pages to obtain more information about supported format.

Quantum GIS

Type: Freeware, open-source

Platform: Windows, Linux, Macintosh

Last update: 2008

Personal experience: Medium

Possibly the best basic cross-platform GIS; great support for WMS, WFS and PostGIS. Nice georeferencing plugin, too. Is incorporating support for GRASS functions.