Processing preferences

Users can select the option to process either the downscan (455 or 800 kHz) channel or primary (200 kHz) for vegetation (the previous EcoSound only processed 200 kHz Primary).  Both channels have performed well in preliminary tests but the outcomes appear highly dependent on local conditions (depth, water clarity, vegetation type and density). We recommend users run their own tests to determine which one performs best for the environments in which they are working.

Select a buffer that controls how much of the map output is interpolated or extrapolated. Select the grid cell (minimum mapping unit) that defines the minimum resolution of any particular point on the map. If you are mapping small ponds with dense transect spacing, 1m grid cells are appropriate. Mapping large lakes with wide transects, consider larger grid cells and buffers.

Insert an offset that will be added (positive number) or subtracted (negative number) from individual depth measurements for every uploaded trip automatically. Vegetation height will be lowered if the new depth is shallower than the vegetation but vegetation height (e.g., negative depth offset) will not be lengthened if a positive offset is put in place. This setting will be used most often for users who have a transducer that is a fixed depth below the surface.

This setting controls the minimum length of a plant (expressed in biovolume as a decimal) that could be detected by EcoSound algorithms. Note that in deeper waters 1% represents taller plants than shallow waters. This setting is an important control against bottom debris erroneously being detected as vegetation. Often the algorithms do not know what is debris and what is vegetation. Now, users can control this setting. EcoSound processing will set the final vegetation coordinate value to zero for points where vegetation is preliminarily determined to be less than this amount.

As the depth gets shallow (e.g., less than 1 m), the target separation between the transducer and the bottom becomes quite narrow and difficult for the algorithms to confidently separate noise from bottom and plant characteristics in these high energy environments. Users can set the depth at which any vegetation or bottom hardness points shallower will automatically be discarded. In contrast, in deep areas, sometimes thermoclines or insect emergence can be mistaken for deep growing vegetation. As such, users can now set a maximum depth of plant detection whereby any points that are interpreted as vegetation deeper than this threshold will be converted to biovolume values equal to zero.

Users also have the ability to apply these global settings or customize their settings on an individual basis for a specific trip or merge of interest.