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Quadrat surveys on Mangrove forests in Borneo

Satellite view of Borneo within Mappt, where we will explore the ability to conduct Quadrat Surveys on Mangrove Forests.

Satellite view of Borneo within Mappt, where we will explore the ability to conduct Quadrat Surveys on Mangrove Forests.

The unique power and simplicity of Mappt lies in its’ ability to handle large amounts of data stored in layers with various formats and structures. This was previously very difficult to achieve in a device as small as an Android tablet. Gone are the days of lugging bulky laptops, hard drives, data folders and antennae of various shapes and sizes in order to complete field work tasks! Now Mappt even allows you to collect field data completely offline, without any connectivity dependencies to WiFi, cellular or otherwise.

We’re always excited about describing novel ways to digitise and store complex data within Mappt. Especially when prior data collection methods were particularly tedious to scribe (usually on paper) and then transcribe onto digital computers later for storage, formatting and analysis! This is true for the case of conducting Quadrat Surveys – a method commonly used in vegetation/coastal surveys designed to monitor all aspects of the environment, fauna and flora. Even just 5 years ago during my Environmental Science degree, we were still conducting Quadrat surveys with a physical Quadrat square made out of PVC pipe.. and we’d spend all afternoon writing out a huge range of data attributes by hand for each sampling location. Then of course, no one could ever find their field notes when it came to put the data together in group projects..

I’m getting a bit side-tracked, but it is legitimately exciting to return to Quadrat surveys with a savvy new digital tool in Mappt. Below I’ll go into detail on using the gridding tool for conducting Quadrat surveys, with a focus on mangrove areas in Borneo. Be sure to get out your tablets and load up Mappt to follow along!

Quadrat surveys using Mappt Grid Tool

To begin our excursion into quadrat surveys with Mappt, what we are doing is essentially achieving an identical sampling outcome using a digital version of a quadrat. This has many benefits; you don’t need to lug around and physically place a big quadrat on your sampling locations in the field, you won’t disturb any flora or fauna and you can rely solely on GPS within a handheld map on a tablet to know your location at all times. These benefits will all lead to higher quality data, whilst also greatly simplifying the field work process. Win-win!

borneo mangrove qudarat survey restoration rehabilitation

Defined mangrove restoration areas have been digitised in Mappt for quadrat sampling.

You will still need to define your quadrat areas and size etc first, following an established methodology. You can use random stratified sampling or another method to ensure statistical robustness in your quadrat sampling. Once this has been decided, you can produce precise GPS points for the quadrat survey and easily map out your points in Mappt. This is where the gridding tool comes in! To get started with creating a vector gridding layer:

  • Position the map centred on where you would like the grid to begin, you can enter precise GPS points after if desired
  • Tap on the  button to Add/Load Layer
  • Select ‘Insert Grid’ 
  • In the Grid Properties window, enter the specifications for your grid.

 

borneo mangrove sampling quadrat mappt grid tool

Once you have clicked Insert Grid in Mappt, this table will appear for customising grid properties.

You can change the grid’s position in the properties window that appears, by altering the Lat & Long values to match your precise sample location(s). In this table you can also set the cell units, number of rows, columns and cell size of the grid to match your Quadrat methodology. For example, if you plan on sampling 5x5m Quadrats, set the number of rows and columns each to 5 with a cell height and width of 1m. For the Borneo example, this will enable me to precisely map out survey points for mangrove flora within 1m2 squares within my 5x5m Quadrat. You can also set a bearing for the grid, if you need to have it laid on a particular angle over the landscape.

borneo qudrat survey grid tool mappt

Properties Window options for drawing your quadrat grid.

You can choose a naming convention for the cells within the grid using the drop-down in the Properties Window to suit your requirements.  In order to map points within the grid, you will need to set the grid type to Polygon. Lastly, be sure to set the Grid Type to vector for storing survey data within the Quadrat grid. Once you’re happy with your settings, click on ‘Create New Grid’.

Final list of options within the Properties WIndow for the Gridding tool.

Final list of options within the Properties WIndow for the Gridding tool.

Now we’re ready to start sampling with our fresh new Quadrat laid down! You should see something like the below on Mappt:

borneo quadrat survey mappt grid tool

Quadrat drawn over Borneo mangrove rehabilitation site using Mappt’s Grid Tool.

Adding Field Forms to Manage Complex Survey Data in Mappt

In order to begin adding sampling points within the Quadrat, we should first set up a field form so that we can quickly enter data for each new point in Mappt. To do this, long-press on the Quadrat layer you’ve just created to open the options table. Click on the Attributes Tab across the top then click the ‘Add’ button on the bottom of the page to begin adding data attributes.

Here you can add attributes to your field form for quick & easy data collection in the field.

Here you can add attributes to your field form for quick & easy data collection in the field.

There are a number of different Attribute Types that can be selected to fulfill different data format requirements. Select the most appropriate type for each of your desired data attributes. For example, for Species type/composition the best option would be a multi-select list, which you can fill out with a range of various species names to be included. Click on ‘Required’ and ‘Include in Wizard’ to ensure that a selection will be prompted each time a field worker adds a new point within a Quadrat survey. This is a great way to digitise the collection of a range of complex data, which is usually the case for Quadrat Surveys, in a simple form on a tablet!

borneo mangrove survey field data form

When adding a survey point, a list of Mangrove species to select appears from a pre-filled field form detailed above.

Repeat the above to add all unique data attributes required for your particular survey project. When it comes to adding survey points in the field, be sure that the appropriate Quadrat layer is selected for the survey data. Line up the crosshair on Mappt within the correct 1m2 square in the Quadrat, then click on the ‘Add Point’ button in the top-left of the Mappt screen. The Attribute Form Wizard will prompt the field worker to fill out the data for each attribute. Lastly, they will see a summary table in Mappt to confirm/rectify any issues before adding the point to the layer.

Field form summary table showing all the entries for each data attribute.

Field form summary table showing all the entries for each data attribute.

The field worker simply needs to repeat this for all the survey data they need to collect within each of the Quadrat areas that were decided for the sampling project! Mappt stores all of the data within the same project, which can easily be exported upon return from the field for use in a desktop or web-based GIS. Better yet, the project could be built in Mappt Air beforehand, so each field worker can simply upload their data to Mappt Air into a single, dynamic and synchronised project repository following each sampling exercise! No more duplication and recquisition of multiple data files streaming from an unmanageable amount of sources, no need for extensive time handling data management. For more info about this powerful collaboration & data synchronisation tool, check out the Mappt Air Website.

Exporting data from Mappt

To export the data manually, simply follow these steps:

  • Select the Export option using a touch gesture on the  button
  • Tick the boxes next to the layer(s) you would like to export
  • You are then able to select the format and delivery option for your data, each of these depending on your particular project requirements.

The Export window will ask you to select a file format to export from the list shown below. Shapefiles or CSV files will both be common outputs for Quadrat survey data, depending on the software that will be used for further analysis.

List of file format types to select for exporting your field survey data.

List of file format types to select for exporting your field survey data.

Following your data format selection, you will then be prompted to choose an output location for your data export. You can select to export the data to the file system of the tablet itself, or you can choose to export the data to external sources including Gmail, Google Drive and more for smooth data storage and management!

How do you use Mappt for field surveys? We always love to hear how our users are kicking their project goals with our favourite mobile mapping tool. Feel free to reach out to colby@takor.com.au any time with your success stories, and I’ll be sure to feature it in our blog. Also remember that support is always available if you have needs beyond this tutorial. No question is a silly question when it comes to GIS! You can reach out any time at support@takor.com.au with any queries.

If you would like to know more about using Mappt as an efficient and robust field inspection utility, please contact us at: support@mappt.com.au

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