Action Required

Programs that converted to Biotics 5 prior to Release 5.3 (before March 27) require reprocessing of their spatial features for data consistency and, if desired, to reflect the new minimum mapping unit (MMU) for a new default map scale. See explanation below.

Background

The mapping scale used in Biotics 4 was based on a 1:24,000 USGS topo map for U.S. programs and, typically, a 1:50,000 NTS map for Canadian programs. The minimum mapping units associated with these map scales were 12.5 m and 25 m, respectively. The mmu was applied as a procedural buffer to the Source Feature to ensure visibility of the spatial feature at a map of the given scale.

For programs that converted to Biotics 5 prior to the release of version 5.3, the default map scale used was 1:36,118, resulting in a minimum mapping unit of 18 m. This was not applied to the spatial features during the conversion, so existing data brought in from Biotics 4 still reflects the original 12.5 m or 25 m procedural buffer, whereas newly created features or features modified after conversion reflect the 18 m procedural buffer. This results in a discrepancy in the spatial features which needs to be rectified by making the procedural buffer consistent. Fixing it will require that spatial features be regenerated, during which time your system will be offline between one and two hours. The downtime will be scheduled during overnight hours to minimize disruption.

The original decision to use the 1:36,118 scale map as the default was made to split the difference between the U.S. and Canadian map scales. Discussions, both internally and with programs, suggested that a more appropriate map scale to use by default within Biotics 5 is 1:18,056 rather than 1:36,118. Both these scales are standard scales used by commercial public map services, including the Esri basemaps available for use within Biotics 5. Given that basemaps are available at the more detailed and accurate scale, it makes sense to take advantage of the better data. That being said, it is up to your program to decide which scale you would like applied to your Biotics 5 instance as the default.

Application

Communicating the scale and hence minimum mapping unit (mmu) distance applied within the Biotics 5 instance is integral to data collection and mapping within Biotics 5. The minimum mapping unit is used to determine whether the Field Observation represents a small area (<mmu in every direction), a linear area (<mmu in one direction, >mmu in the other direction) or large area (>mmu in every direction). Collecting information regarding the area of the observed element while in the field is therefore critical, as it is the first step in the spatial feature development and indicates the Conceptual Feature Type. Likewise, Locational Uncertainty Type of Negligible is defined as uncertainty that falls within half the minimum mapping unit distance (i.e. ≤ ½ mmu; for a map scale of 1:18,046 with a minimum mapping unit of 9 m, ≤ 4.5 m). Finally, a Procedural Buffer is applied to Source Features with Negligible or Linear locational uncertainty to ensure that the resulting EO is visible at a map of the given scale.

The procedural buffer is applied to any SF smaller than the mmu purely for the purpose of visualization,. However, it is not reflected in the actual SF (as evident by exporting the SF shapefile from Biotics 5), nor in the resulting EO, except in the case of SFs with Locational Uncertainty Type of Negligible or Linear. For a visual of this, please see the Summary of Spatial Feature Development.

Further information can be found within the related help topics:

• Minimum Mapping Unit 
• Conceptual Feature Type 
• Negligible Locational Uncertainty 
• Linear Locational Uncertainty
  
• Procedural Buffer
• Summary for Spatial Feature Development

Please contact Whitney Weber by Friday, May 9th to schedule the spatial data rectification and indicate whether you would like to utilize the 1:18,056 (default as of 5.3) or 1:36,112 scale map, programmatically.