- Tree mapping involves geo-tagging trees (marking the latitude and longitude) and incorporating tree details such as the species, girth, height, age, health condition and even the canopy diameter.
- Environment activists and mapping technology experts assert that when the information about geo-tagged trees in cities such as Mumbai are made public, the citizens can track the trees. This in turn, improves governance and public participation in tree conservation.
- As GIS mapping technologies improve, Mumbai authorities are planning to study additional parameters that could improve the understanding of more tree features. But the data is available on a beta feed only on government network systems, and not accessible by the public.
In 2018, activist Gopal Jhaveri in Mumbai, discovered that four coconut trees in his area, Borivali, had been poisoned by miscreants to achieve a clear view for an advertisement hoarding. Jhaveri lodged a police complaint against the unnamed offenders. The police investigations failed to make any headway as there was no proof that a tree previously stood at that spot. Jhaveri decided to approach the municipal authorities for evidence. But he realised that the Brihanmumbai Municipal Corporation (BMC) did not have or share records of individual trees, despite it having done a Geographical Information Systems (GIS) tree mapping census just the previous year.
Who then, has a record of all the trees present in Mumbai city, Jhaveri wondered.
Jhaveri suggested to the authorities that the GIS tree mapping data be made public to clamp down on rampant illegal tree cutting. This would enable transparency about tree figures and the ones cut for infrastructural projects.
What is GIS tree mapping and why is it important?
Geographical Information Systems or geo-tagging is the process of adding geographical identification data to any fixed object. Tree mapping involves geo-tagging trees (tagging their latitude and longitude) and incorporating tree species digitally by adding details such as girth, height, age, health condition and even the canopy diameter. These details can be incorporated into the city maps digitally through software applications.
Field officers visit trees and upload the geographical co-ordinates of every tree, marking their exact latitude and longitude on a global positioning system (GPS) instrument. However, trees can also be geo-tagged directly via satellite/aerial/drone imagery, without necessarily visiting them.
Lalitesh Katragadda, the creator of the now-inactive Google Map Maker and former Head of India Products, Google, says that while the exact number of geo-tagged trees can be identified from satellite images, identifying the specific tree species may be possible “only if the street view imagery and drones are used extensively.”
However, he feels that the real challenge is not so much about the mapping, but the lack of transparency in public data. “As per the provisions of the Information Technology Act, 2012, any kind of public data that is collected for public purposes, which does not have security ramifications to it, should be made available in public domain,” he says. Katragadda is also fellow at iSPIRIT, a non-profit tech think-tank that works for digital democracy to get governments to make data public.
Strongly advocating for such data to be made public, Katragadda argues that when such visual digital maps of issues that impact citizens are made publicly available, it helps activate concerned citizens to support governments to resolve complex city-based problems, including tree conservation.
GIS tree mapping examples in Indian and international cities
Mumbai took up geo-tagging as part of its tree census in 2017, to monitor illegal cutting and identify patches of land for plantation.
R. Prabhakar from the India Biodiversity Portal, who leads a citizen initiative to geo-tag trees, shares the data on the IBP portal, so that it could be made available on a public platform for observation and analysis. He says that citizen initiatives would be effective for tree mapping, but this will have to be done in partnership and support of local governments and municipalities.
He narrates the example of Bengaluru where he says there has been much talk about geo-tagging trees for quite some time but nothing much has happened on the ground. “Citizens have been mapping trees at random in Bengaluru, but there needs to be systematic and concerted efforts in partnership with local bodies,” he says. He also highlights Pune’s attempts at mapping, “The city has beautifully put up statistics online for its citizens.” Internationally, Prabhakar views New York as a good model, with all trees there being geo-tagged and the information available online.
Tree mapping enthusiasts say that macro numbers about the overall number of trees in an entire city or entire ward are quite useless for citizens, and instead what is critically relevant for them, is the availability of information at the local neighbourhood level.
Even for a road widening project which requires the felling of a few trees, Prabhakar opines that local citizens must be involved for updating the figures of number of trees. The government cannot do constant verification without public support, he says.
The wait to make Mumbai’s tree data public
Deputy Superintendent of Gardens, Mumbai, Dnyanadev Mundhe stated that they plan to study many new features in the forthcoming tree census, the tendering process for which could be started anytime soon.
“Currently, the tree data with us is limited to the total number of trees, their species and the ward-wise number of trees. Since, the concept of heritage trees (trees that are over 50 years old) had not yet been introduced, it was not considered as a distinct category in the earlier Census data, but now it would be. Since, we are now better-versed with the GIS data mapping, we plan to study additional parameters that could help us understand more features and dimensions about the trees in Mumbai. Yes, it may help to give people access to the GIS tree mapping data, but currently that is not possible. As of now, the data is available on a beta feed only on our official network systems,” said Mundhe.
The way forward for geo-tagging trees
The Rewilding Aarey project undertakes tree protection and sapling plantations in Mumbai’s Aarey Colony, which has a rich green cover. Aarey, however, currently faces a threat of tree-cutting to make way for the upcoming metro train and other infrastructure. Sanjiv Valsan who is part of the rewilding project says, “While geo-tagging could help identify trees that got cut “illegally” it may not necessarily work in the current context of rampant “authorised” tree cutting. The system here is now geared up to facilitate “authorised” tree cutting on a huge scale, with government sanctions. Even if a person were to be officially prosecuted in a case of “unauthorised” illegal tree cutting, the token punishment of about Rs. 5,000 per tree is usually less than the resale value of the wood.” Valsan feels that tree cutting permissions are liberally granted and objections raised by citizens are merely accepted as part of the official procedure with no action taken on them.
The Rewilding group geo-tags the saplings it plants. “While it helps to locate them for maintenance and to track survival rates, it does not provide any helpful data in terms of the health of the upcoming tree,” says Valsan.
Citizen bodies such as the Mumbai March, which Jhaveri is a part of, have been demanding that the garden department of Mumbai make its tree data public. “Not only will it strengthen our fight against tree cutting, but also GIS-tagged municipal tree records can be used as evidence in courts. It will also help us plan our city better. We shall be able to plan our trees better we shall be able to figure out which type of trees our city lacks, be it indigenous or rare or heritage and take up the plantation of those trees,” says Jhaveri.
Banner image: Dahisar in north Mumbai. Photo by Saumitra Shinde/Mongabay.