Author: biobasemaps

BioBase is a cloud platform for the automated mapping of aquatic habitats (lakes, rivers, ponds, coasts). Standard algorithms process sonar datafiles (EcoSound Product). Depth and vegetation maps and data reports are rapidly created and stored in a private cloud account for analysis, and sharing. This blog highlights a range of internal and external research, frequently asked questions, feature descriptions and highlights, tips and tricks, and photo galleries.

Recent publication on curly-leaf pondweed

Just a quick post to announce the recent publication of a paper authored by Contour Innovations Chief Aquatic Biologist Ray Valley documenting recent short-term declines of the invasive curly-leaf pondweed potentially due to heavy winter snowfall.  You can access the article here or email Ray at rayv@contourinnovations.com and ask for a pdf copy.

Abstract

Curlyleaf pondweed (Potamogeton crispus) is a long-established, nonnative aquatic plant common throughout southern and central Minnesota that is thought to be expanding northward. Curlyleaf pondweed typically grows abundantly in spring in productive lakes and then senesces in midsummer, often followed by algae blooms. We report observations of widespread, short-term declines in curlyleaf pondweed cover that appear linked to winter snow depth on frozen lakes. These findings suggest that climate change may greatly affect habitat suitability for curlyleaf pondweed. As Minnesota lakes warm with less snow cover limiting light penetration, curlyleaf pondweed growth will likely increase. These observations form the foundation for targeted follow up studies that more precisely describe conditions limiting the growth and expansion of curlyleaf pondweed in north-temperate, North American lakes.

 

Later this winter, Ray will post a blog that goes in more detail about this long-established invasive aquatic plant and the potential for its management to positively affect water quality by reducing internal nutrient loading.  In a nutshell, the jury is still out and more robust monitoring and research is needed if Minnesota is to efficiently and wisely invest tax payer dollars dedicated to clean water work in the state.

Aquatic Plant Species Domination – Collaborative Research Using BioBase

Contour Innovations is proud to announce a collaboration among aquatic industry leaders to better understand aquatic species domination and lake ecosystem changes over time.

FIGURE: Left map: sampling points where Eurasian watermilfoil was present (yellow) and absent (X) during a survey on Gibbs Lake, Rock Co. WI (77 acres) in summer 2012.  Points are overlain on a vegetation biovolume “heat” map from passively collected sonar data and processed by ciBioBase.  Red colors represent vegetation that is growing near the surface.  Right map: Eurasian watermilfoil “Dominance” map rendered from both species survey and biovolume data.  Areas that are yellow and red areas where Eurasian watermilfoil is dominating the plant community and growing near or at the surface.

For over a decade, point-intercept survey methodology for aquatic plants has become a standard tool for lake resource managers and researchers.  The standard methodology entails sampling a uniform grid of points on a lake noting presence absence of species at each point with a rake. It is a relatively rapid way of objectively sampling aquatic plant species communities in a repeatable fashion.  However, the methodology’s primary downfall as a standalone method is its insensitivity to abundance of plants (i.e., 1 sampled sprig gets the same weight as a large bed at any one point).  Using passive collection of aquatic plant abundance with acoustics while conducting point-intercept surveys and simple GIS overlay methodology, we are demonstrating how species presence/absence layers can be combined with complementary biovolume (% of water column occupied by vegetation) data to form a more complete survey of both species AND abundance.  Further, using both species and abundance layers, we developed a ‘dominance’ index for each species sampled and demonstrate how dominance of any or all species can be used as an aquatic plant management or lake habitat monitoring tool.  Examples from Eurasian watermilfoil and Hydrilla infested lakes are used, as well as lakes with no known invasive species.   Future applications could utilize other environmental datasets (e.g., climate, land cover & use, water quality, etc.) to model the potential and realized outcome of a host of environmental stressors on the probability that invasive species will come to dominate a water body.

Aquatic biologist Ray Valley commented, “We’re excited about where this research can take us.  Collaboration among experts throughout the US allows us to draw on a wide knowledge base and study ecosystems from a broad geographic range.  As this historical centralized dataset grows over the coming years, continued collaboration will help us understand and forecast true patterns in dominance and ecosystem effects of invasive species introduction.”

If you have interest in participating in this collaboration or have suggestions, please contact Ray Valley at RayV@ContourInnovations.com

Participating Groups Currently Include:

Contour Innovations LLC, Minneapolis MN
University of Florida Center for Aquatic and Invasive Plants, Gainesville, FL
Wisconsin Department of Natural Resources Bureau of Science Services, Madison, WI
Minnesota Department of Natural Resources Fisheries Research Unit
North Carolina State University, Department of Crop Science, Raleigh NC

We’ll keep you updated along the way!  Centralization is powerful stuff when it comes to aquatic plant research!

Lake Bottom Depth Precision and Accuracy

In an addendum to an earlier post, we continue to evaluate the accuracy and precision of BioBase depth outputs.  Lowrance has been in the depth sounding business since 1957.  They have tight factory calibration standards whereby depth should never be more than 2% different than the actual depth.  Of course then we expect depths to be spot on on hard bottom surfaces where truth can be easily measured.  But what about in mucky bottoms which are common place in many lakes, ponds, backwaters throughout the US and abroad?  With this in mind, in late May of 2012, we traveled to Pool 8 of the Mississippi River near LaCrosse WI to do some testing in a mucky, moderately dense vegetated backwater (Figure 1).  At some point we have to step back and ask, “what is the bottom of a body of water?”

Figure 1.  Vegetation cover and biovolume (% of water column occupied with vegetation) in Pool 8 of the Mississippi R. in LaCrosse WI on 5/29/2012.  Average biovolume was 30% during the survey.

The most difficult aspect of this testing was to get an objective estimate of the true depth.  In other words, where exactly did the plants end and bottom start?  Typically, investigators use a survey rod like that seen in Figure 2 to estimate actual bottom based on where they feel resistance on the survey rod.  Piece of cake over sand.  Not so easy over flocculant silt and muck or vegetative areas.

Figure 2.  Measuring bottom with a survey rod in a mucky Minnesota Lake.  Typically, the survey rod will sink several inches into the bottom before the surveyor feels resistance and judges the depth to the bottom

Many experienced surveyors will tell you that the rod will sink into the muck some distance before you feel resistance.  There is a positive correlation in the distance it sinks and how mucky the bottom is.  So, we went into this investigation expecting deeper rod depths measured than ciBioBase outputs. 

Accurate and precise results in mucky, vegetated bottoms

After 30 points measured with the survey rod, we compared the results with the ciBioBase depths measured in the same location.  We were pleased to see very high precision with a Coefficient of Determination (R^2) of 0.94 and a systematic difference in depth of only 4.9″ (Figure 3).  The depth of 4.9″ was quite possibly the average depth where we first felt resistance of the survey rod.  The upshot here is that ciBioBase depth outputs are highly precise, consistent and accurate even in mucky vegetated bottoms.

Figure 3. Accuracy and precision of ciBioBase depths measured against depths collected with a survey rod in the mucky, vegetated backwaters of Pool 8 of the Mississippi River near LaCrosse, WI.

Point-Intercept on Steroids

Who would’ve known that an obscure technical report describing a sampling methodology would become a classic in the world of Aquatic Plant Management and be adopted as a standard by lake service providers and government agencies?  Although it was old hat in the world of terrestrial Botany and Forest Ecology, Dr. John Madsen appeared to be the first to make point-intercept a standard tool for aquatic ecologists and lake managers with his Army Corps of Engineers Technical Note No MI-02 published in 1999 entitled “Point Intercept and Line Intercept Methods for Aquatic Plant Management.”

Briefly summarized, point-intercept methodology entails creating a grid of GPS points on a waterbody and traveling to those points and sampling the aquatic plants in those areas typically by throwing a double-headed rake and pulling up whatever it catches (Figure 1).

Figure 1. Contour Innovations Aquatic Biologists Jesse Amo (back) and Ray Valley (front) conduct a point-intercept vegetation survey while logging acoustic data on Orchard Lake, Dakota Co. MN.

The simplest and most objective application of the method is to simply record the presence of each species on the rake.  This does not lend much insight into how abundant each species is at each point and a mat of surface-growing vegetation gets the same weight as a lonely sprig (Figure 2).  To address this short-coming, several adaptations to the method have been made by various practitioners including ranking the abundance of different species on the rake.  Although some may argue it’s a “better than nothing” measure of relative abundance, I would argue, not much.  There is no straightforward way to objectively rank the abundance of 5 different species in a gob of plant matter on a rake like seen in Figure 1.  As a consequence, results are not repeatable and four different investigators could produce four different results for the same sample.  Further a relative ranking lends little biological information about the architectural structure or canopy height of aquatic plants.

Figure 2. Conceptual figure of a point-intercept sampling point in two contrasting environments.  In the pure application of the method, if the rake intercepts the diminutive sprig in panel B, it would be given the same weight as the thick mat in panel A.
Biological processes, water quality, physical habitat and recreational conditions all hinge on the state of aquatic plant ABUNDANCE in a waterbody.  As I have described above, point-intercept or any subjective adaptation is not well suited to address aquatic plant abundance concerns.  Nevertheless, point-intercept has many strengths and one shouldn’t throw the “baby out with the bath water.”  Rather, ciBioBase offers a powerful and efficient way of getting more out of your point-intercept species sampling.
To add biovolume to your point-intercept surveys all you need is a Lowrance HDS depth finder, a $10 SD card from your favorite electronic retailer, and a subscription to ciBioBase (single lake and unlimited pricing are available).  No additional set up is necessary.  No technical mapping experience needed.  Just hit record, and jump from point to point like you’ve done in the past.  The HDS unit will passively record the GPS signal and acoustics the entire time.
After you return from the field, upload the data to ciBioBase, get a cup of coffee and catch up on some email.  Approximately 30-min to an hour later, one of the new emails in your inbox will be an alert from ciBioBase informing you that your plant abundance and bathymetric map is processed and ready for viewing.
Not only does passively logging sonar data while conducting species surveys require no additional work, but you sample important interim areas between points and get understanding of the TRUE coverage of plants (not just the frequency of plants sampled with your rake).
Unleashing the power of Point-intercept by using ciBioBase
Although ciBioBase comes with many analytical tools, its full potential to inform aquatic plant management is realized when the data is exported out of ciBioBase and into GIS for analysis with other data layers (Figure 3).
Figure 3. ciBioBase users have the option to export processed point data along their GPS track (Point) or  the uniform grid created by kriging interpolation (Grid).  Users can then import these files into GIS for further analysis with their point-intercept data layers.
By converting the ciBioBase grid text file into a Raster grid and using a “point on raster” analysis utility available both in ESRI’s ArcGIS and Quantum GIS (an open source GIS program), users can grab the biovolume value for a point-intercept sampling point (Figure 4).

Figure 4. Example of biovolume data (grid of blues, purples, and reds with increasing density or biovolume getting a “hotter” color) imported into GIS and overlain with point-intercept species data (yellow points are northern watermilfoil – a native stand-in for its unwelcome foreign cousin Eurasian watermilfoil).  The Point Sampling Tool in Quantum will extract grid values from one raster layer and attach them to a different point-layer.
In the hypothetical example in Figure 4, anywhere where milfoil is present we can see how dense the vegetation growth was at the sampled point and around it.  By using the Point Sampling Tool in Quantum that captures the biovolume grid cell value for each surveyed point, we found that for all milfoil points, average biovolume was 65% (with many points at 100% or surface growing).  For all other vegetated points, biovolume was only 45% with many less 100% values.
How can information on species abundance lead to better management decisions than presence alone?  It is generally unrealistic to eradicate most invasive species, and often a more realistic objective is to manage the abundance to an acceptable level.   Perhaps the surface growing tendency of milfoil (i.e., biovolume = 100%) is the primary management concern and that reducing “biovolume” to say, 45% with much less surface growth like other native plant species, would be a desirable result.   Presence/absence data from point-intercept surveys alone will not inform whether plant abundance is being managed within desirable levels.
Case Study: Whole-Lake Treatments of Fluridone with Both PI and Biovolume data
Valley et al. (2006) describe results of whole-lake applications of the herbicide fluridone to a nutrient-rich Minnesota Lake (Schutz Lake, Carver Co. MN).  As part of the evaluation, hydroacoustic surveys of vegetation biovolume were conducted before and after the treatments in addition to point-intercept species surveys.
The treatments reduced Eurasian watermilfoil below detection levels, but also directly or indirectly played a role in reducing the other dominant native species in the lake, coontail.  In fact, almost all submersed vegetation disappeared 1-2 years following the treatment; however, one would never get that indication by solely looking at the point-intercept statistics (Figure 5).  

Figure 5. Mean whole-lake percent vegetation biovolume from hydroacoustic surveys (bars) in Schutz Lake, Carver Co. MN from Valley et al. 2006.  Percent frequency of occurrence of all vegetation from point-intercept surveys conducted at the same time (numbers above bars).
What had occurred was a situation that went from Figure 1A to Figure 1B.  To a rake, these environments are the same, to a lake manager and concerned citizen, they are strikingly different.  Evaluating results with Point-intercept frequency sampling alone can mask unintended harm to water quality and lake resilience.
In the 2000’s, point-intercept methods gave resource managers an objective and rapid species assessment tool.  Now, ciBioBase adds a critical third dimension to these surveys with no additional effort or training. By implementing ciBioBase as a part of standard aquatic plant assessments, resource managers and citizens will be better informed about the true state of vegetation growth in a lake and how it’s changing as a result of environmental change and our management responses.

References
Madsen, J. D. 1999. Point Intercept and Line Intercept Methods for Aquatic Plant Management. APCRP Technical Notes Collection ERDC/TN APCRP-MI-02.
Valley, R. D., W. Crowell, C. H. Welling, and N. Proulx. 2006. Effects of a low-dose fluridone treatment on submersed aquatic vegetation in a eutrophic Minnesota lake dominated by Eurasian watermilfoil and coontail. Journal of Aquatic Plant Management 44:19–25.

Paradise Lake Improvement Board (MI)

Contour Innovations has recently adapted the ciBioBase platform and pricing options to support the mapping initiatives of local government units, home owner associations, and improvement boards.  One of the most recent additions to this project has been the Paradise Improvement Board in Carp Lake, MI (Lower Peninsula) and we’re excited about it!*

The Paradise Lake Improvement Board (paradiselakeimprovementboard.com), through crowd sourcing and citizen science concepts, can now quickly determine the location and abundance of aquatic vegetation for management interventions and quantitative evaluation of the effectiveness of those techniques.   

There’s no technical expertise required!  Our biologists walked the volunteers of the PLIB through a demo account to demonstrate the key features for success with ciBioBase and discuss the recommended settings and collection techniques.    

 
 It’s this simple

Led by board member Catherine Freebairn, the PLIB purchased 2 Lowrance™ HDS units that will be set up as portable units for the lake group and an unlimited upload subscription to ciBioBase.com.  These units will be used to map Paradise Lake during dedicated mapping time as well as during pleasure cruises with passive collection.  With each minute on the water, the PLIB volunteers will be collecting vital statistics on aquatic vegetation, bathymetry, water temps, water volumes, and water clarity, all by hitting “log sonar” on their new HDS sonar units.  All of this data will be stored in their private online account. 
Aquatic biologist Ray Valley commented, “Protecting our lakes demands understanding of what lies beneath the surface and how its changing as a result of environmental changes and our responses to them.”
Using the innovative ciBioBase System, the PLIB has started building a historical database of their aquatic environment to monitor vegetation abundance and other important water quality characteristics over time.   They can now quickly determine the location and abundance of submerged aquatic vegetation for management interventions and quantitative evaluations of effectiveness of those techniques.  This database is the catalyst for efficient management today and in the future.  By gathering  this data each time someone is on the lake, the Board can crowd source the mapping effort and share information with their service providers for collaborative and objective decision making.  

“The PLIB has always shown a substantial passion for their lake and we feel that their early adoption of our powerful technology will be rewarded on many fronts,” said Contour Innovations’ CEO Matt Johnson.  “It’s very easy to work with groups like the PLIB who see the big picture in lake management and monitoring and want to see results.  They develop close relationships with their service providers and home owners to work hand-in-hand in understanding the best opportunities to reach their goals.  This is the first time that groups like this can use acoustics for accurate vegetation mapping and ciBioBase fits perfectly within their strategy,” he added.  

The PLIB will be working with their service providers (who will also have access to uploads and maps) to make important management decisions, monitor changes, and objectively evaluate if management interventions are having their desired effects.  With the support of all involved, including Contour Innovations’ own aquatic biologists, the future looks bright for Paradise Lake and anyone that enjoys all it has to offer!
 An Example of a Lake Mapped with ciBioBase
 Aquatic Vegetation Displayed in % BV (water column occupied by plants)

If you’re interested in finding out more about ciBioBase and how it can help your association or improvement district, please contact us and we’d be happy to set up a person demo for you with one of our biologists.  Please contact Jesse Amo for additional details:  JesseA@ContuourInnovations.com

For more information on the Paradise Lake Improvement Board please check out their website at paradiselakeimprovementboard.com.

*Contour Innovations does not release personal information about our customers.  We obtained permission from the PLIB before this media release.

Precision Management-Time to Quantify

Lake Harriet Monitoring Before and After Harvester. . .

A multitude of factors impact the health of aquatic systems creating a need to monitor lakes’ “vital signs”.  In the same way it is expected that a medical doctor will do more than glance at a patient and say: “you look fine” the same is needed for our lakes.  A number of different vital signs are necessary to give a precise assessment of human health and our aquatic systems are no different, they are complex biological systems.  ciBioBase provides many “unchecked” parameters that have not been assessed until now in an automated processing system.  Two trips on a small section of Lake Harriet in Minneapolis collecting “vital signs data” have already told a story about big changes in the aquatic community.  What more can we learn about this complex ecosystem by simply monitoring with ciBioBase on an ongoing basis?
A data collection trip with ciBioBase in late June on Lake Harriet revealed what you might expect from an unseasonably warm spring in a lake infested with Eurasian watermilfoil(EWM).  Aquatic plant growth was several weeks ahead of schedule with EWM dominating the sample area on north shore and already being matted on the surface.  The majority of near-shore areas sampled exhibited near 100 % EWM biovolume (% water column occupied).  In fact, in the far east and west reaches of the sample area our survey-boat was skirting matted EWM too dense to navigate through.  Wherever vegetation occurred (percent area coverage) on the June 18th survey the biovolume average was very high, due to it being composed primarily of EWM (average of 54.4%).  
BEFORE:
 

In late August a comparison trip was completed, navigating the same transect line from the June trip using ciBioBase following the Lowrance HDS track overlay on the unit.  A striking feature noticed shortly after getting on the water was…..Where was all the topped-out vegetation?  The transect sampled on June 18th skirted topped-out EWM, but on August 22nd no topped-out vegetation occurred in the same sampling area.  This excerpt from the Star Tribune written by Bill McAuliffe on June 10th explains: “The Minneapolis Park Board’s milfoil harvest began with a single mower.  . The harvesting each year generally requires at least two passes through each lake. Cedar Lake was scheduled for mowing Friday. After that, Lake Harriet is on the schedule.” (View the article by clicking here).  That would explain the drop in average biovolume in vegetated areas from 54.4% to 16% and overall average biovolume for the entire sampled area from 28.3 to 5.1%.

AFTER:
*Automated Reports Generated for Each Trip Uploaded to ciBioBase

ciBioBase not only displays that the average biovolume in vegetated areas for this study site dropped from 54.4% to 16% and overall average biovolume for the entire sampled area from 28.3 to 5.1%, but it also outlines vegetation distribution.  Spatial characteristics such as the shift from about 30% of the sampled area having a biovolume of  >80% to 0.34% of the sampled area having a biovolume >80% after the EWM harvest are also a part of the ciBioBase data output.

ciBioBase has enabled users to precisely compare changes in biovolume and spatial distribution of vegetation; pinpointing changes and quantifying their outputs.  This means precision monitoring and management using quantifiable target goals while leveraging objective “before and after” monitoring data that is easily collected, processed, and viewed with the ciBioBase system.

Knowing precisely “where and how much” are critical components to knowing if management plans are effective.  Another excerpt from Bill McAuliffe’s Star Tribune article states: “The Lake Minnetonka Conservation District launched its two mowers Thursday, about on schedule because it uses school teachers to run them, said Judd Harper, who manages the district’s milfoil removal. But weed growth on the lake is “a lot worse than it was last year,” Harper said.”  ciBioBase provides numbers behind “a lot worse”.

Using the ciBioBase system and historical database comparison, it is now possible to quantitatively identify year to year and other temporal trends.  Managers can now implement corresponding management based on sound scientific data and quantitative metrics.  ciBioBase is the key to precision management!

TRIP COMPARE FEATURE IN CIBIOBASE

* %BV (% of the water column filled with plants)
ANOTHER SHOT OF BAIT FISH PICKED UP BY STRUCTURE SCAN

 

ABOUT CIBIOBASE:

ciBioBase removes the time and labor required to create aquatic maps! The System was engineered to provide automated cloud based bathymetric and aquatic vegetation mapping and historical trend tools for aquatic habitat analysis. ciBioBase leverages log file formats recorded to SD cards using today’s Lowrance™ brand depth finders and chart plotters. Data you collect while on the water is uploaded to an online account where it is processed by our servers automatically! We rely on automation to make vegetation mapping cost effective by reducing the technical skills, staff, and hours to produce vegetation abundance maps from raw sonar collection. With the human element gone, you get accurate and objective mapping at lightening speeds! The result is a uniform and objective output all over the world!

What’s this Kriging Business?!

Thanks to advances in Geographic Information Systems (GIS) computing technology, evaluating changes to lake bottoms over time has gotten much easier!  Prior to GIS, biologists and surveyors would go through great pains to ensure that repeated data collection in study areas of interest would precisely fall on the same area or transect.  If this condition was not met, data would have to be thrown out because biologists could never be sure that the difference seen between two time periods was real, an artifact of sampling a different area, or a product of sampling in a different way.  Consequently, efforts from multiple groups collecting similar data in the same system but in a slightly different way could not be leveraged.  This is an unfortunate missed opportunity that BioBase uniquely handles.

First, BioBase uniformly interprets acoustic signals and the output is the same regardless of the skill level of the individual collecting the data.  Second, BioBase employs kriging to create a statistically robust uniform map output that figuratively turns Survey 1 by Bob Smith from an orange into an apple and Survey 2 by Amy Johnson in the same area from a grapefruit into an apple.  This is unique to kriging which is a geostatistical procedure.  All other standard interpolation methods are simply 3D representations of the input data and each map will look different depending on the precise location of your survey points.  Only kriging turns different fruits into apples.

Continue reading “What’s this Kriging Business?!”

Contour Innovations’ New Office

We recently came to the realization that we had outgrown our original office so it was time for an upgrade! Many of you that have been following our progress have seen that Contour Innovations has been hiring and growing as ciBioBase continues to expand its subscriber base across the world.  We’re sad to leave the birth place of Contour Innovations but we’ve move into a great creative space in NE Minneapolis.  This move is an exciting event for CI!

    

Our new address:
Contour Innovations, LLC
1229 Tyler St. NE, #120   
Minneapolis, MN 55413

This is not a ping pong table, it’s a morale booster . . . okay, it’s a ping pong table:

If you have plans to be in the Minneapolis area, be sure to drop in and check out the new digs . . . and challenge us to a game!

About Contour Innovations, LLC:

Contour Innovations, LLC was founded in 2009 to develop a SaaS Platform for automated processing, interpreting, and centralizing a warehouse of industry specific GIS/spatial data.  We leverage this Platform to launch unique Systems that provide relevant information technology tools to different industries. Our initial systems are focused on acoustic processing of user collected sonar data.  Our first System launch with ciBioBase is already changing the world of aquatic habitat research!

About ciBioBase:

ciBioBase removes the time and labor required to create aquatic maps!  The System was engineered to provide automated cloud based bathymetric and aquatic vegetation mapping and historical trend tools for aquatic habitat analysis.  ciBioBase leverages log file formats recorded to SD cards using today’s Lowrance™ brand depth finders and chart plotters.  Data you collect while on the water is uploaded to an online account where it is processed by our servers automatically!   We rely on automation to make vegetation mapping cost effective by reducing the technical skills, staff, and hours to produce vegetation abundance maps from raw sonar collection.  With the human element gone, you get accurate and objective mapping at lightening speeds!   The result is a uniform and objective output all over the world!

Contact us for details about testing the System or checking us out in a demo account.  We also sell Lowrance HDS units to outfit your data collection boat!

Bathymetry Mapping with ciBioBase!

At Contour Innovations, we often preach the importance of aquatic plant mapping and monitoring, but of equal importance and capability is ciBioBase bathymetric mapping features.  ciBioBase comes with many features that automate the tedious, mundane, yet highly technical GIS processes associated with creating a bathymetric map.  Water resource and lake managers and researchers should be spending their time and talents focusing on thorny management problems, not compiling and managing volumes of data and trying to map them in GIS.  The science of acoustic bottom detection and GIS mapping has been extensively tested, verified, and proven with standard methods.  We automate this.

Because ciBioBase maps only areas you cover up to a 25-m buffer outside of your track, you are assured that maps do not include extrapolated data.  40-m spacing of transects with a criss-cross design assures you that you will get complete coverage and smooth contours (Figure 1). 

Figure 1. Transect coverage showing a “criss-cross” design to assure a high quality bathymetric map.

The Trip Replay feature in ciBioBase further allows you to see disruptions in the contours (Figure 2).  As in the case with Figure 2, there was a temporary disruption in the transducer signal, thus giving an erroneous depth (Figure 2 and 3).  In ciBioBase, these erroneous depths can be edited out; thus creating a smoother, more accurate bathymetric map and associated statistics.

Figure 2. Desktop verification of bathymetric outputs with ciBioBase’s Trip Replay feature.
Figure 3. Areas of disrupted signal can be deleted and the trip reprocessed for a more accurate and smooth bathymetric map.

Other times, these little “donuts” occur because depths temporarily enter a different contour level (e.g., 3ft contours with series depths = 5.99, 6.0, 5.99, 5.98, etc).  Although the 6.0 depth is likely legit, it may be more aesthetically pleasing to remove the 6.0 depth to prevent the creation of a 6ft donut hole.

Once you are happy with the output with individual trips, you can merge them in ciBioBase to create a uniform output (Figure 4).

Figure 4.  Merging function in ciBioBase that allows users to merge individual files or trips into a single, uniform map.

Tying Bathymetry to a Benchmark Elevation
When mapping bathymetry, it may be important to tie the water level to a benchmark water level elevation.  In our Minnesota Lake example, we went to the Minnesota Department of Natural Resource’s Lakefinder website and found important water level information (Figure 5).  On 6/5/2012, we surveyed McCarron’s Lake in Ramsey County, MN.  On 6/7/2012, the elevation-corrected water level reported by citizen volunteers was  840.84 ft above sea level.  The Ordinary High Water Level  (OHW) benchmark for McCarron’s is 842.21 ft (Figure 5).  Using the Data Offset feature in ciBioBase (Figure 6), we can simply add 1.37 ft (elevation correction) plus 1 ft (transducer correction) to get a bathymetric map that is corrected to the OHW (Figure 7).  This eliminates water level as a confounding variable with repeated bathymetric surveys on the same waterbody.  The final products are high resolution, blue-scale imagery as seen in Figure 7 (up to 1-ft contours) or the actual point and grid data that can be imported into any third party GIS or statistical software (Figure 8).

Figure 5. Water level information for McCarron’s Lake in Ramsey County, Minnesota USA.
Figure 6. Data Offset feature in ciBioBase that allows users to correct their bathymetric data to a benchmark water level and transducer depth.
Figure 7. Bathymetric imagery with resolution (both bottom and pixel) that can be controlled by the user.
Figure 8. Export point data along your traveled path or the kriging interpolated grid for use in third party GIS or statistical software.

Life is good in the cloud…

Because of the centralized, cloud-based platform of ciBioBase, we see trip uploads into the system from all types of lakes, ponds, and reservoirs throughout the country and even abroad; so our acoustic and geostatistic algorithms have seen it all!

See for yourself in our demo account at ciBioBase.com.  In the login page, enter demo@cibiobase.com and “demo” for the password.  Operators are standing by to answer any questions you may have!

Lake Mapping and 800 kHz DownScan

BioBase Now Offering 800 kHz DownScan in its dynamic Trip Replay feature.

 

Trip Replay is taking a leap forward with the new option to view your data using the 800 kHz DownScan option when recording with the StructureScan™ add-on.  Anyone that has been uploading data gathered with StructureScan™, by logging all channels, can now view past and future trips with this new feature.

You may have seen our earlier posts about the BioBase Trip Relay feature.  Your raw data collection is automatically processed by our powerful cloud servers and fully mapped with kriging algorithms and other geo-statistical considerations. Once processed, you can then replay the entire trip, watch your boat travel along your transects, and ground truth the % BV heat map with the water column cross section (on the right side of the image above).   This feature allows our customers to verify every trip output for accuracy and provide objective evidence for anyone that questions your aquatic vegetation maps!

The power and accuracy of the Lowrance™ HDS StructureScan™ allows us to offer a new and amazing cross-section view (DownScan) of the water column for each trip in the Trip Replay feature.  As you can see from the images below, this feature provides amazing views of bottom and vegetation.  It is even possible to notice changes in vegetation types or habitat cover type under your boat.  With our waypoint feature, you can identify vegetation transition zones and areas of interest for typing and delineation.

 

Please let us know if you would like to add StructureScan™ to your current data collection hardware.  Although not mandatory for using BioBase, this option can be added to any HDS™ system at any time for great views underwater.  For details on using or recording StructureScan™ please request a copy of our Standard Operating Procedures.

Another great feature added to the powerful BioBase System.

ABOUT BIOBASE

BioBase was engineered to provide automated cloud based GIS, aquatic vegetation mapping and historical trend tools for aquatic habitat analysis.  BioBase leverages log file formats recorded to SD cards using today’s Lowrance™ brand depth finders and chart plotters.  Data you collect while on the water is uploaded to an online account where it is processed by our servers automatically.   We rely on automation to make vegetation mapping cost effective by reducing the technical skills, staff, and hours to produce vegetation abundance maps from raw sonar collection. With the human element gone, you get accurate and objective mapping at lightening speeds!

Check out more anytime at www.BioBaseMaps.com and on our BioBase BLOG

Translate »