Destruction of Mangrove forest and the need for its documentation.

What's happening in Sal River? River dredging or Mangroove smothering!? Let's find out in this post. The river in question is located in Salcete Goa. Recently the river has been in the news due to the ongoing tussle between the Traditional fishermen community and the state government authorities to stop the dredging work. As per government view the dredging work is being carried out to desilt the river so as to allow sufficient depth for river navigation, fishing and other activities that will benefit the Traditional fishing community however the Traditional Fishermen community believes that their livelihood is at stake due to the environmental destruction caused by the haphazard dredging activity. 

In the below Sentinel II satellite time-lapse imagery from 2019-to 2022 of the river stretch between Varca and Carmona Village, it appears as if the river has been stripped of its jewels- the mangroves. 

A ground inspection of this stretch reveals piles of matured mangroves trees smothered to death under heaps of sand. A number of dead tree stubs protrude out of the sand on the river bank with machine cut marks an evidence of its death caused by humans. Take a look at the videos below captured along this stretch in Carmona on 25/07/2021 and in Varca on 28/12/2021 respectively.

 

Dredge caught in action while causing destruction of Mangrooves near Orlim bridge, on 28/12/2021. 

The extent of the loss is hard to quantify as most of the trees are buried beneath the heaps of sand, in spite of this there still a significant evidence left on the ground which needs to be documented properly so that the concerned authorities are held accountable. This documentation can be achieved by launching citizen science initiatives which can make use of open souce GIS software to collect geotagged ground data which can then be utilized to prepare authentic technical reports and measure the loss in terms of biodiversity, economic, ecological functions, watershed functions etc. Only by preparing such a report we will be able to draw the attention of the concerned authorities and seek answers from them. In the absence of such authentic data to substantiate claims the authorities in power easily plead ignorance to the subtle voices of the weaker sections of the society. GeoSensitive is capable of providing the technical GIS expertise and train volunteers to collect data and prepare authentic maps (sample below) which can be verified and acted upon by the concerned authorities. 

Sample Map from Geotagged data

To get in touch write to geosensitive.goa@gmail.com

Thank you.

References 

https://timesofindia.indiatimes.com/city/goa/stretches-of-sal-worst-hit-among-states-rivers-finds-pollution-body/articleshow/66112034.cms 

https://timesofindia.indiatimes.com/city/goa/traditional-fishermen-oppose-sal-river-desilting-seek-inspection/articleshow/80104683.cms

https://www.thegoan.net/goa-news/phase-ii-of-river-sal-dredging-fishermen-environmentalists-cry-foul-term-ongoing-dredging-work-as-illegal/80677.html

https://www.heraldgoa.in/News-Today/Ongoing-mode-of-dredging-in-River-Sal-to-put-livelihood-of-fishermen-at-risk-say-surveyors/186880

Customized Thematic Maps: Village Road Network

In a world full of ready access to knowledge, getting the right direction becomes crucial. At a click of a button, we can get access to a lot of data however what we often really need is a focused blueprint. Welcome to the world of customized thematic maps. This post is about how a customized thematic road network map can give us an edge in planning. 

As a part of our endeavour to document our entire village biodiversity, we need to plan documentation trails for field data collection. This sounds straightforward. Google maps? You may say. here are some difficulties 

• Village roads are better known to the village people rather than google. (Think of all your childhood secret trails and escape routes after stealing mangoes)  
• Satellite imagery/maps do not represent village/ward/other boundaries however local landmarks do. 
• Most often, the type of road, its status is not shown on ready available roads maps. 
• All you need is just the Road map minus the clutter.

Therefore we took up this task to compile a road network map for Betalbatim Village in Salcete Goa. We will keep on updating this but for now, we shall plan our documentation trails for birds, religious structures etc.. with this map. 

Presenting a clutter-free thematic road map of Betalbatim village below. 

Road network overlaid on Satellite Imagery

How will you use your village road network map? Tell us in the comments below. 

Thank you, readers. 

GeoSensitive: Simplifying Decision Making - Services Offered

GeoSensitive prides itself in being a service provider to the bottom level decision-maker and upwards. We deliver spatial insights using Geographic Information Systems and Remote Sensing for decision making that impact lives, livelihoods and our environment. Our speciality is that we do this using a collection of some of the worlds leading open-source GIS platforms, skills we have honed over a period of 5 years. This allows us to provide the best and latest technology solutions at significantly lower project costs.

Our services cover two broad aspects

• Providing Geographic Information Systems Services and Remote Sensing Services for quick decision making and facilitating better and efficient management of resources to the people of Goa.
• Offering professional GIS skill development training on the world’s leading open-source GIS platform i.e., QGIS. 

 Our customers include- NGO'S, Local panchayat bodies, Businesses, Researchers, Farmer groups etc. 

Technical Services

Geosensitive provides specific technical expertise for the clients. These include but are not limited to 

• GIS mapping
• Field Data Collection/Surveying
• Terrain Analysis
• Hydrological Modelling
•  Digitization of existing maps

Training Services

Geosensitive provides education to the client. This can take the form of workshops, coaching, on-the-job support, etc. The following workshops can be curated as per the needs of our clients.

• Basic mapping using QGIS- 2-days (hands-on program).
• Advanced mapping using QGIS- 6 days (hands-on program).
• Ground truthing and Field data collection – 2-days (hands-on program).
• Basics of Satellite Remote Sensing – 6 days (hands-on program).

Specialized Services

Geosensitive provides specialized expertise and advice to the client.

• Spatial Analysis
• Site Suitability Analysis based on set criteria
• Remote Sensing Applications

Project Management

This includes completing a broad range of tasks for the client that is delivered as a package.

• Providing training and follow-up for employees.
• Overseeing implementation of the system.

We are always looking to upgrade our knowledge and expertise by tackling new problems and are happy to discuss burning issues concerning your environment/locality. Write in the comments below.

Drop-in an email at geosensitive.goa@gmail.com to connect with us and we will be happy to respond.   

Mobile GIS for Ground Truthing

In this post, I wish to highlight the usefulness of mobile GIS for ground-truthing work. First of all, what is ground-truthing? Simply put it is verifying the features/facts present on the ground. Why am I talking about ground-truthing? Recently a lot of villages in Goa received notices from various government departments saying that officials will be deputed for ground-truthing work related to Coastal Zone Management Plans.  This exercise is very important considering the fact that many important features such as sand dunes, khazan lands, fish breeding areas, fishing areas, water bodies, mangroves, coastal infrastructure and several other cultural and heritage structures were missed in the proposed plans. Most of the villages in Goa identified these errors and made their own plans with the help of NGO'S and handed these over to the State Coastal Zone Management Authority in the form of hard copy maps and also in the form of soft copy Georeferenced Pdf file format.    

It is observed that the deputed government officials are finding it difficult to accurately locate these features onto the cadastral plan used by them. A very easy approach to solve this problem is the use of GIS apps on a GPS enabled mobile device.  

The app allows one to stack/overlay georeferenced layers of maps one above another and using the inbuilt GPS on the mobile device one can easily identify their location on each of the maps. The maps in this case would be 1. Proposed CZMP 2. Peoples CZMP 3. Cadastral Plan and 4. Satellite Imagery. The location is updated as one moves from one location to another just like a car navigation system but with your choice of the base map instead of the default satellite/road imagery. In addition to this, the app can also be configured to collect additional attribute data in the form of geotagged photographs, text, numbers, booleans etc. 

Screenshot shows the app interface with Betalbatim Village Peoples CZMP stacked on top of Satellite Imagery, Blue dot indicates my location at the time of taking this image. 

Detailed view of the Peoples CZMP map with a scale and finer details on zooming in on the location. Note: The location of the device is out of the scene at the time of taking this imagery hence no blue dot indicating the location on a map.  

Thank you. 

GeoSensitive- Providing Remote Sensing and Geographic Information Systems intelligence for informed decision making.

Interactive Web Maps: Goa Covid-19 Status as on 25/05/2021

Every once in a while we deal with data in the tabular form. Long tables of data are boring, especially when the data in question has some spatial attributes to it. So when I noticed the government website disseminating covid related information using a table it got me thinking, can this be done better? can we tell the covid story more efficiently so that anybody can understand the situation? and so I thought of making an interactive webmap of the covid-19 status in Goa as on 25/5/2021. Not only was I successful in creating one but it was all done using free to use open source tools including QGIS, WebMap plugin, and Git. 

Goa Covid information is available on the government portal at https://www.goa.gov.in/covid-19/. 

The boring form of spatial data presentation

    A better way of presenting Spatial Data.

Check out the interactive webmap below.  You can play around with the point and polygon features to access additional details such as the number of reported active cases, taluka name, place name etc. 

So what do you think? .... webmaps V/s Tables. 

Google Earth Engine: A powerful application for Earth Scientists

Hello Readers!

Have you ever faced the difficulty of downloading a vast amount of satellite data due to slow internet? ever troubled by the limited processing capabilities of your computer system? lack of storage to handle the data? fear not! because now there exists a solution to all these problems-Google Earth Engine is the answer to all your satellite image processing requirements.  

Google Earth Engine is a cloud computing platform to process various kinds of spatial data, especially remote sensing satellite data. One can now access thousands of satellite imagery with just a few lines of code something unimaginable in the last decade is now possible. Thanks to GEE. 

GEE is the go-to tool for anybody seeking to use remote sensing data because of its powerful cloud data processing and its free access and availability of a vast number of datasets. Moreover, there is excellent documentation for one seeking to learn how to use it. With just the basic knowledge of Javascript syntax, one can get started on the platform using javascript API on the google earth engine code editor. There are also several user forums on social media and open access courses where one can find relevant information and help. 

Google Earth Engine Code Editor interface and a simple image classification procedure performed for Betalbatim Village, Salcete Goa showing 5 classics viz. Green: Vegetation, Yellow: Agriculture, Red: Builtup, Blue: Water, White: Bare ground/sand. 

This might seem a bit overwhelming for a newcomer without the knowledge of coding however let me assure you that with each line of successfully executed code your confidence skyrockets. This has been the case with me (a non-programmer). When you realise the potential that this platform holds you will automatically get the motivation to learn.  So if you are somebody who has a desire to find solutions to real-world problems using satellite data on GEE then Introduction to JavaScript for Earth Engine is the place to start with or any basic course in javascript. Once you have a basic knowledge of javascript head over to the GEE documentation to learn how to use this platform. for those who already have a programming background, you can try completing the exercises from this free course material End-to-End Google Earth Engine (Full Course Material). 

Happy learning.

Thank you. 

Cool things one can do with QGIS: Animated Tracks

QGIS is one of the fastest developing and widely used open source GIS platform out there. It offers some really cool GIS capabilities. One of the cool things to do is to create animated track of your awesome adventures.  I was able to log my bike ride track using an app on the phone, which I later used to create this amazing animation.  

Animated Bike Ride Track

As you can see we wasted some time at several pit stops waiting for our friends to join in and one major halt for snacks and tea before we zig-zag into the mountains at the end of the trip. This animation itself tells us the story of our ride. how cool is this? 


I learnt this QGIS trick courtesy of  Ujaval Gandhi  who has generously shared his high quality QGIS course material for free.