The BMC finally got going with its tree census to quantify the green cover in the city yesterday. Five teams of five members each set out to record information about trees. The survey, which began with Oval Maidan yesterday, is being conducted using devices enabled with the global positioning system (GPS) technology.
These enable surveyors to record latitude and longitude of a tree, thereby determining its position. They will also feed in information about each tree based on a number of other parameters (see box for details). The contract, worth Rs 2.07 crore, has been awarded to Sar IT Services, a firm based out of Nagpur. The company has been given 12 months to complete the survey.
While the GPS-enabled devices allow for capturing a variety of information, the system has no particular way to account whether a tree has already been counted or not. “There is no system to verify if a lane or a few trees have been missed out from the census,” said Sunish Subramanian, founder of Plants and Animals Welfare Society (PAWS), an NGO.
'Won't mark trees'
In the previous survey conducted in 2008, census takers made marks on trees to indicate that it had been counted. “We’re not using the earlier system. There will be no markings on trees to show that it has been counted. All data will be uploaded on BMC’s website after completion,” said SVR Srinivas, additional municipal commissioner, who is in charge of the garden department.
He added that despite having no physical markings, the system would allot a unique number to each tree. “This number will help us identify if a tree has been cut,” explained Srinivas. Yet another problem in the system is, there is no method to record the age and height of trees. “We will have to take approximate numbers in these cases, as the GPS device cannot calculate it,” said an employee of Sar.
How the survey will be conducted
>> Five teams with five members each will cover different areas in the city
>> Each squad will have GPS equipment to record latitude and longitude
>> The enumerator will record data of each tree according to 25 parameters such as botanical name, ownership, category, economic importance, physical characteristics, status (alive/dead), healthy or diseased (if any) and any other special comment
>> This data will be compiled and uploaded on BMC’s website
Areas not covered
>> Aarey Milk Colony, Goregaon
>> Sanjay Gandhi National Park, Borivli
>> Bhabha Atomic Research Centre, Trombay
>> Mangrove covers
Rs 2.07 cr
Cost of the 2014 tree census
Number of trees counted in the 2008 tree survey
Number of species recorded in the 2008 survey