These use cases primarily address AfSIS data products and services that are either needed or available at the beginning of the second year of the project term. Two of these deal with the acquisition of legacy data for soil profile data and management trials; a third addresses the base maps that have been developed from remote sensing imagery and will be used to construct digital soil maps of key soil properties. The fourth concerns the dissemination of field, lab, and analytical data from the sentinel landscapes. The fifth describes the use of the training modules for AfSIS field and lab protocols and the final case focuses on the use of online mapping tools. We anticipate the development of additional use cases as project activities progress and more data becomes available. The figure below outlines the data and functions covered by AfSIS use cases. Items in blue are addressed by the use cases given below; the others will be addressed in additional use cases to be developed in the coming year and will motivate further system development.

USE CASE 1a: Legacy soil profile data capture

Purpose
Legacy Data from Soil Reports are entered into AfSIS SLDB (Legacy Soil Profile Database) by staff at NARS offices for retrieval and analysis


Background
The map below indicates the existing paper soil maps and the number of soil profiles (legacy data) in various databases. The spatial and soil profile data, which has been incorporated in a database, includes: Southern Africa, Central Africa, and Senegal. For the other countries, the existing soil survey reports, old paper maps and soil profile data needs to be collected. It is estimated that half of the legacy data is located at NARS and the other half of the data is available at ISRIC (e.g. WISE database, map library). To complete the SSA soil legacy database the following is required: collection of data at the NARS, screening and quality control, data entry, and compilation of the database. The sequence in which this the soil legacy database will be compiled follows the work at the sentinel sites.  This data, along with base maps (described in Use Case 3) and the new data collected by AfSIS (described in Use Case 4), will be used to produce new digital soil maps for SSA.

 
Actors
•    Users:

Scientists responsible for completing soil reports, other NARS staff

System developers

•     System Components: AfSIS Soil Profile Database entry system, local soil profile database

 Pre-conditions

Legacy soil reports have been prepared and are located at the workstation to be used by NARS staff.

Scenario

1.    Users. The system developer configures the AfSIS Soil Profile Database entry system to include each value on the legacy soil reports to be processed. Next, each value on the legacy soil report form is matched to a corresponding standard element defined in the AfSIS Soil Profile database.

2.    Users. The legacy Soil Reports are processed by the scientist sequentially to enter the values from each legacy report into the AfSIS Soil Profile Database entry system.  See Alternative Scenarios.

3.    System Components. The AfSIS Soil Profile Database entry system displays the new profiles and provides an opportunity for the scientist to modify and verify the profiles prior to inclusion in the AfSIS Soil Profile Database.

4.    Users. The values entered from each legacy Soil Report are verified by the scientist before being accepted for inclusion into the AfSIS Soil Profile Database entry system.

5.    System Components. Upon receiving acceptance of the new profiles, the values from each legacy Soil Report populate the AfSIS Profile Database and the local soil profile database.

6.    Users. The scientist retrieves the new soil profiles that have been included in the AfSIS Profile Database.

See Alternative Scenarios.

7.    System Components.  The AfSIS Profile Database displays soil profiles that meet the search criteria to select soil profiles entered within the specified period.

8.    Users. The new soil profiles are selected for access, and analyzed by users of AfSIS in combination with other legacy soil profiles that have been entered into the AfSIS Profile Database by other global partners.

9.    System Components. The  AfSIS Profile Database displays choices for accessing soil profiles from various locations.

10.    Users. The new soil profiles included in the local soil profile database are retrieved and analyzed bylocal partners in combination with other soil profiles for the region that have been entered into the local soil profile database by local partners.

Alternative Scenarios

•    Entry of Values from Legacy Soil Reports

       1. Values from the legacy soil reports are entered manually into a stand-alone microcomputer application, exported to comma-separated value (CSV) files, and sent by email to the AfSIS regional office.
       2. Values from the legacy soil reports are entered manually into an online entry form that populates the AfSIS Profile Database.
       3. Values from the legacy soil reports are entered by scanning forms into a software package that can identify the correct fields to populate the AfSIS Profile database.

•    Retrieval of New Soil Profiles

       1. New soil profiles values are exported from the stand-alone microcomputer application to other software applications for local analysis.
       2. New soil profiles are retrieved from the AfSIS Profile Database by entering search queries specifying the location where data collection occurred.
       3. New soil profiles are retrieved from the AfSIS Profile Database by browsing hierarchically through menus of locations.


Rules
Established standards for describing soil profile data.


USE CASE 2: Base maps (Processed Landsat MSS, TM and ETM+ imagery, Processed 90-meter STRM, Terrain model derivatives)

 Purpose

Serve base maps as regional mosaics. Allow subset and download.

Background

AfSIS base maps have been processed to remove errors, inconsistencies and artifacts from the raw imagery. Common archives of these data are only available as tiles. Creating seamless mosaics will allow AfSIS users to visualize and interact with the data and to download custom extracts.

Actors (Users and System Components)

Users: Scientists, remote sensing community, GIS analysts

System Components:

Image service
Extract service

Pre-conditions

Quality remote sensing imagery must be available for designated locations. Creation of mosaics.

Scenario

1.  Users. The analyst searches for a data product for the geographical region or interest.

2.     Users. The analyst selects the remote sensing imagery of interest as a subset of available extent and selects file format (geotiff or bin).

3.     System Components. Download extract is based on current extent and selected file format, returned via http download or via email link to site (asynchronous).

4.     System Components. AfSIS provides a search query interface that has capabilities for users to enter search queries to find AfSIS data products available in the catalog based on terms entered. Also see Alternative Scenario.

Alternative Scenario

·       AfSIS Remote Sensing Data Product Discovery

o   AfSIS offers capabilities for selecting data products by choosing continents, countries, and regions from hierarchical menus and choosing date ranges of interest.

 Rules

Standard ISO country codes would be used for discovery of data products.


USE CASE 3: Field, lab, and spectral data

Purpose

Populate the AfSIS soil database with field and lab data from sentinel landscapes for public dissemination through a searchable web-based catalog that facilitates downloading of selected data.

Background

Field and lab protocols for AfSIS follow the Land Degradation Surveillance Framework (LDSF).  

Actors (Users and System Components)

 Users: Soil scientists

 System Components: AfSIS field, analytical and spectral databases

Pre-conditions

Soil scientists have hand-held devices with GPS that enable data capture (backup paper copies of the entry forms for field data are used if necessary). Laboratory facilities and spectrometers are available to process soil samples.

Scenario

1.     Users: Arriving at the field site where soil samples will be collected, the soil scientist uses the camera on her hand-held GPS computer to photograph the location and the surrounding area, enters data on vegetation, land cover, land use, auger depths, and soil texture into the field entry form, and uses the device to capture the GPS coordinates.

2.     System Components: Data is stored on GPS handheld for download onto field laptops to be emailed via satellite phones to regional labs.

3.     Users: The scientist collects soil samples. In some cases samples can be scanned using an ASD field spectrometer.

4.     System Components: AfSIS provides capabilities to receive and store the observed values and associated GPS coordinates. AfSIS enables these data to be associated with the photographs to populate the record of data obtained from each location in the AfSIS Soil Sample Database.

5.     Users: The soil scientist accesses AfSIS and searches for soil data from the region by entering a search query containing the name of the region or by selecting from menus in a hierarchical manner.

6.     System Components: AfSIS contains a user interface and provides capabilities to enable the expression of search terms by users and the matching of search terms with terms stored in the database.

7.     Users: The soil scientist selects the locations of the soil test sites that match the location specified and chooses soil properties to be accessed for each site.

8.     System Components: The AfSIS contains a user interface and provides capabilities to select data from individual sites that matched a query and to select variables to retrieve the recorded values from the selected sites.

9.     Users: The soil scientist views the values for the selected variables from the chosen locations and selects the option to create a map that displays colors that the scientist assigns to ranges of values.

10.  System Components: The AfSIS has capabilities to display the values of selected variables that match a chosen location and provides features that enable the assignment of colors to ranges of variables.

11.  Users. The soil scientist views the map that displays colors assigned to ranges of values for selected variables and saves the generated map.

12.  System Components: AfSIS has capabilities to generate and store a map that displays the colors that have been assigned to each range of values for the selected variables from chosen locations.

13.  Users. The soil scientist hypothesizes about soil properties in proximity to soil site locations by modifying the map to add colors in proximity to displayed colors and saves the map.

14.  System Components: AfSIS provides capabilities to modify generated maps and to store modified maps as new maps.

Alternative Scenario

·       Hierarchical selection of soil data

o   AfSIS provides an interface and capabilities to enable the selection of locations from menus to successively specify a continent, country, state, region, county, or city and to match the selected locations with terms stored in the database.

Rules

Soil sampling standards are followed.

Field equipment is calibrated and inspected regularly to ensure accuracy.


USE CASE 4: Training modules for AfSIS field protocols (cumulative mass)

Purpose

Provide guidance and tools on aspects of the AfSIS methodology to support users of the AfSIS methodology for soil sampling and the development of digital soil maps.

Background

Providing access to the AfSIS methodology can improve protocols for practices of agricultural extension agents and soil scientists in the field, the laboratory, and the office.

Actors (Users and System Components)

·       Users: Soil scientists who sample and test soil from field sites.

·       System Components: AfSIS Field Protocol Library

Pre-conditions

Training modules on the AFSIS methodology are available in AfSIS.

Scenario

1.     User. While preparing to improve the protocol used for sampling and testing the cumulative mass of soil from field sites, the soil scientist accesses the online AfSIS Field Protocol Library and searches the library by entering the term “cumulative soil mass”.

2.     System Components. The AfSIS Field Protocol Library generates search results based on the query and displays the list training resources and tools that contain the term “cumulative soil mass”.

3.     User. Reviewing the list of training resources, the soil scientist selects the training resource titled, “Guide for Sampling and Testing Cumulative Soil Mass”.

4.     System Components. The AfSIS Field Protocol Library displays the elements of the selected training resource, which includes the document titled, “Guide for Sampling and Testing Cumulative Soil Mass” and the accompanying video module. The video module is represented by a screen shot from the video and a control panel for playing, pausing, and stopping the video and for adjusting the volume control.

5.     User. The soil scientist chooses to play the video and watches the entire video module, which takes about five minutes. After viewing the video, the soil scientist downloads the video module to her laptop computer so that the video can be shown to others who are stationed at remote locations, locally.

6.     System Components. The AfSIS Field Protocol Library provides capabilities to play, and download video modules.

7.     User. The soil scientist selects the document titled, “Guide for Sampling and Testing Cumulative Soil Mass”. Viewing the table of contents and the first few pages enables the scientist to verify that the selected guide would be useful to have in the field for improving the protocol. The scientist selects the option on the screen to print the guide and then downloads the guide to her laptop computer to share with others.

8.     System Components. The AfSIS Field Protocol Library provides capabilities to print a selected document on a local printer attached to the workstation at the location where the document is being viewed.  The AfSIS Field Protocol Library also provides capabilities to present the document as a PDF file or a Word file for downloading.

9.     User. The scientist gathers the instruments and the materials that are listed in the guide, and loads them in the truck, along with the printed copy of the guide and the laptop computer containing the video and the document, for the trip to the field site.

10.  User. Following the guide and viewing the video module again, the soil scientist uses the new procedure to sample soil at the field site and becomes adept at using the new procedure after collecting several samples.

11.  User. The soil scientist uses the protocol described in the guide to test each sample that was collected and finds that using the new procedure has reduced the time required to obtain each soil sample, has increased the number of tests completed on each soil sample, and has improved the quality of each cumulative soil mass test that was conducted.

Rules

Standards are followed for producing video modules and for video module player.


USE CASE 5: On-line data visualization and analysis

Purpose

Use of AfSIS to support science, agriculture, education, and decision-making

Actors (Users and System Components)

 Users: Scientists, agricultural extension agents, educators, and policy-makers.

 System Components:

Web server
Application server
Map server

Pre-conditions

                  Internet access, data availability.

Flow

1.     User opens map client/interface in browser.

Alt.: User selects thematic area that launches client.)

2.     User can expand layer list tab to toggle between base layers (processed remote sensing imagery) and overlay layers (admin boundaries, watersheds,  soil properties, fertilizer recommendations, sentinel landscapes, field trials, biomes, population, poverty, etc.)

3.     User can toggle on and off between layers

4.     User can pan, zoom in/out, view continental extent and overview map.

5.     User manually zooms to area of interest.

Alt.: Chooses county/region/site from menu dropdown to zoom.

Alt.: Enters place name in search box, selects from list of returned results.

6.     Local map is displayed; users selects layers, performs spatial query.

7.     Users can print map extent.

8.     If Users decide to download data, they can select the control that redirects them to the data download page.


Scenario

1.     Users. Considering the possibility of drought in the region, the agricultural extension agent accesses AfSIS to assess the soil conditions to be considered when planning for the next growing season.  The agent selects the region and local area of interest to identify satellite imagery and topographical maps that are available.

2.     System Components. AfSIS displays the types of imagery that are available for the region and local area of interest, based on the selected menu items.

3.     Users. Satellite imagery, topographical maps, soil maps are retrieved, and used to generate a map that is modified to model projected drought patterns. For possible locations of where drought will occur, soil conditions are analyzed to determine the potential effect on crop yields for local farmers.

4.     Users. The agricultural extension agent creates maps with alternative drought scenarios for presentation to the relief agencies. Using AfSIS during the presentation, the maps are further modified to address questions from relief agency staff about the location of roads.

5.     System Components. AfSIS enables editing of the maps to include roads and allows the modified version to be saved and stored on the system.

6.     Users. Three maps are produced on AfSIS during the meeting to represent different locations where relief could be needed.

7.     System Components.  AfSIS displays the three maps simultaneously for comparison and allows each to be modified and stored on the system.