Resource Information Systems
Department of Land and Water Conservation
PO Box 3720, Parramatta, NSW 2124
(Phone) 02 9895 6163, (Fax) 02 9895 7985
SPADE is a simple spatial viewer that provides access to publicly accessible soil profile data points held by the NSW Soil And Land Information System (SALIS). Most of the 29,000 soil profiles currently accessible through SPADE include information about the landform, vegetation, land-use and soils at the site, and some have laboratory test results. This is a valuable resource to land managers, extension officers, planners, consultants, Government agencies, educators and students.
SPADE operates over the Internet in Version 4 and later browsers, and is freely accessible via its homepage at http://spade.dlwc.nsw.gov.au. Initially, the user sees a map of NSW. They can select a Catchment or Local Government Area to zoom into, or may zoom and pan manually to locate their area of interest, assisted by the scaleable topographic map context layer. By clicking on one of the data points, the user can access an easy-to-read Soil Profile Report detailing the landscape and soils at that location.
SPADE is the first step in providing Internet access to SALIS’ substantial soil and land dataset. A more advanced spatial viewer now under development will provide enhanced access to both point and map polygon information from SALIS over the Internet in the future.
Whether you are interested in knowing more about your local catchment, the most sustainable way to use the land, how the local landscape has developed over time, or even what might or might not grow in your garden, chances are that somewhere along the line you’ll need some information about the soil. In the past soil information has been difficult to find, either because it was not easily accessible, was available only in highly technical forms suitable only for soil scientists, or it simply didn’t exist. However, through the application of convergent technologies in data storage and information access, members of the NSW community can now gain direct access to a progressively greater cross-section of the NSW Government’s natural resource information via the Internet— and in particular, in this instance, information about NSW’s soils.
Taking Advantage of Technological Convergence
The use of digital databases gives potentially tremendous advantages in terms of speed and ease of access to information, particularly in the case of a centralised system founded on consistent, rigorous principles of data management. The Internet paradigm allows the general public to access and interact with information from almost anywhere in the world, providing they can get online. Combining these two technologies unlocks the value of information by drawing it together into a single consistent source and then making it easily available at minimal cost to those who need it.
A few years ago, the NSW Government’s Natural Resource Information Management Strategy (NRIMS) group conceived a program known as ICMISS (Integrated Community Mapping Information Support System). ICMISS takes advantage of the convergence of database and communication technologies by developing a framework by which geographic natural resource information can be distributed from multiple remote data servers in different Government agencies to the NSW community via the Internet. This means that natural resource data from different scientific disciplines held by different organisations can be brought together and accessed on one screen as maps, using the same viewer technology.
More recently, ICMISS has evolved into CANRI (Community Access to Natural Resource Information). CANRI has expanded its focus to include other organisations and agencies, including those from the general community, and is also aligning itself with agreed international standards for spatial data management and distribution including those from OpenGIS. As part of the CANRI framework, spatial viewer interfaces can be developed which access specific data sources from within that framework, including particular kinds of natural resource information.
More information about CANRI is available from its Webpage at http://www.canri.nsw.gov.au. Here you can also access the various interfaces developed to take advantage of the CANRI information sharing framework, including access to NSW river levels and water quality, air pollution indices, native vegetation regulation and Landcare groups.
In early 2000 the Soils Information and Planning branch of DLWC recognised the opportunity that this technology provided for distributing soil data, and began the development of an interface to display the extensive resource of soil information it holds. Conveniently, DLWC already has a centralised database containing soil profiles across NSW, known as the NSW Soil And Land Information System (SALIS). This data has been contributed both by Departmental officers (particularly Soil Surveyors) and by over two hundred Members of SALIS external to DLWC, with the number of profiles in SALIS increasing on an almost daily basis. The number of soil profiles contained in SALIS currently exceeds 48,000, of which around two-thirds is accessible to the general public.
The importance of extending the value of this information by making it directly accessible to the general public has long been recognised, particularly in the case of farmers, land managers and groups that can benefit from access to soil information in their local area. Actually accomplishing this aim has proved more difficult, not only because of the problems in interpreting technically-based information into useable forms for non-specialists, but because of the fundamental technical problems in trying to distribute such a large amount of information. However, in early 2000 ICMISS provided a ready means of distributing soil information, and the NSW Office of Information Technology (OIT) approved an application for funding, so thus was born the Soil Profile Attribute Data Environment, (SPADE).
How SPADE Works
Keeping the interface simple and easy to use was a primary factor in SPADE’s design and operation. Consequently, the system puts all user functions within easy reach inside one basic Web page. A screenshot of the SPADE viewer page is shown in Figure 1 below.
Figure 1: SPADE Web page (showing Tamworth area)
The page consists of several components. In the centre left of the page is the main map panel, with its associated controls. Below is a scale bar that shows the width of the map view in kilometres (km). To the right is the locator map panel, which shows where the main map view is on a NSW scale. The locator map panel also allows a user to define an area using a bounding box for display in the main map panel. A set of simple instructions for use are also provided here, although more comprehensive descriptions and instructions are available on the SPADE Help page (accessible via a button on the interface toolbar or via hotlinks elsewhere on the page).
The SPADE main map panel itself (see Figure 2 below) is quite simple, with a series of controls for configuring the map view and accessing the data within it. These comprise, from left to right, a zoom in tool, zoom out tool, pan tool, information tool, a help button and a reset button. Both of the zoom tools operate by either a single click on the main map panel or by drawing a bounding box. SPADE also allows a user to zoom immediately to a selected spatial extent, either a NSW catchment or a Local Government Area, using the bounding boxes provided above the button bar. These two types of extents were selected because they are meaningful to a wide range of potential users, and allow a user to rapidly find their area of interest.
The SPADE map view comprises two layers. The uppermost is a layer of soil profile points, shown in the main map panel as orange triangles, which is active and can thus be queried. The second, underlying layer is a context layer of scanned topographic map information that alters itself to best match the scale of the map view. For example, at larger scales the context layer displays 1:250,000 topographic map information, whilst for smaller areas (where available) the layer displays topographic map data down to 1:25,000 scale.
Figure 2: Example of SPADE main map panel (triangles show soil profile points)
Downloading Soil Information from SPADE
Once the user has navigated to their area of interest, they can select the information tool (i button) then click on any one of the soil profile points (marked with an orange triangle) in the main map view. SPADE then produces a Soil Profile Report (see Figure 3 below) for the selected point.
The Soil Profile Report describes the basic landform and soil characteristics recorded at the selected point, plus a basic set of soil laboratory test results (if recorded). It uses a flowing readable style rather than formatting the data attributes into a rigid tabular structure, and does not refer to attributes where no data has been recorded.
Because the soil profiles have been described by different people with different levels of expertise and for different purposes, soil profile descriptions in SALIS exhibit considerable variation in the level of detail described. Consequently there may be far more information available for a soil profile than can be described in the Soil Profile Report. Additional information can be obtained by contacting SALIS staff using the email address or telephone number at the bottom of each Soil Profile Report.
Figure 3: Example section of a SPADE Soil Profile Report
Technical Issues with SPADE
Most of the interface technology embodied in SPADE had been previously tried and tested in other ICMISS interfaces. However, an issue specific to SPADE was the sheer volume of data being distributed through the interface (~24,000 points when first built, now ~28,000 points). This proved to be quite a challenge, particularly for larger scale views where several thousand soil profile points might be visible at any one time. Ultimately, the potential problems with bandwidth and server overload could only be solved by limiting the number of points displayed in any one view. In SPADE, the maximum number of points displayable is limited to 500, and no soil profile points are displayed on a map that is wider than ~140 km.
The precise architecture used to develop SPADE has caused some problems both in operation and maintenance. Because the behaviour of the interface is hard-coded, there is limited scope for enhancing the existing interface, and making changes is difficult. Another problem with the SPADE servlet is that it can be quite sensitive to certain stored Internet content on the user’s computer. Java errors resulting from this problem may prevent the SPADE spatial viewer from functioning properly. SPADE works best if stored Internet content is minimised or removed.
The Future of SPADE
SPADE is likely to remain in its current form for another six months or so. We plan to replace SPADE with a more capable spatial viewer (known provisionally as SPADE Plus) which allows the display and manipulation of multiple layers of spatial information and the querying of underlying attributes. Particular targets for distribution using SPADE Plus include DLWC’s Soil Landscape map series and the Acid Sulfate Soil risk maps. Also, SPADE Plus will be developed in an environment that provides for easier ongoing enhancement of the interface, unlike the current system.
The CANRI program has received nearly $4 million in capital funding from NSW Treasury over four years from July 2000, which translates to $800,000 to $850,000 for projects across all agencies and other organisations in each financial year. Proposed projects are supported according to a prioritisation of natural resource datasets by the NSW Government’s natural resource agencies in consultation with the NSW community. Continued CANRI funding would see the SPADE Plus development commence in July 2001, with delivery in early 2002.
In the interim, SPADE’s reporting capability will be enhanced through the replacement of the single basic Soil Profile Report with three new reports, ranging from a summary report similar to that currently implemented in SPADE to a full description of all soil attributes recordable for a profile record. This should provide enhanced access to information, particularly for more technical users. The reporting upgrade should be in place by 30th June 2001.
The current version of SPADE is the first step along the road to making the vast majority of DLWC’s soil and land information directly available using Internet technologies. SPADE has provided valuable experience in distributing soils information via the Internet. Further developments along the same line will build upon this initial capability and, in the long term, provide much greater levels of access to NSW’s resource of soil and land information.