Software helps monitor the health of city trees
Trees reduce air and sound pollution, hold temperatures down around them, minimize damage by altering the speed and direction of the wind—all in addition to beautifying cities. But if not well cared for, trees can topple over, causing injury and death, blocking roads, and cutting off power. For example, from January through May 2017, 2,192 trees fell in the city of São Paulo, for an average of 14.5 per day. If the benefits of an urban forest are to outweigh the disadvantages, this greenery must be well looked after. This is the purpose of three Brazilian-designed software applications that schedule pruning and cutting, inform tree age, and even indicate whether a given species can be planted in a given spot.
Closest to completion is the Arbio program, developed at the São Paulo State Institute for Technological Research (IPT) with the chief aim of managing trees inside road systems and green areas. “The application allows you to compile inventories by logging vegetation at a given location and to plan forestation by defining the sites and species best suited for planting,” says biologist Sérgio Brazolin, head of the IPT’s Trees, Wood, and Furniture Laboratory and leader of the team that developed the software.
Brazolin explained that Arbio is designed to store individualized data on each tree, such as site; botanical identification (scientific and common names); surrounding conditions, including thoroughfares, type of associated property, and conditions of sidewalk and median strip; electrical and telephone wire interference with the crown; status of trunk and roots; measurements of tree size; and presence of disease or termites.
Working in partnership with Google, Digicade, a company based in Belo Horizonte (Minas Gerais State), developed the Geosite Urban Forestry system, which likewise facilitates urban tree monitoring. “It’s a system integrated with geographic data that makes managing city trees more efficient by combining inspection, pruning, and management operations within a single tool,” says João Carlos Tavares da Silva, development coordinator at Digicade.
In Botucatu, São Paulo, the company CAA Tecnologia da Informação is finalizing an application whose functions and goals are similar to those of Arbio and Geosite. “The program can be used to plan and manage trees and also foster public engagement,” says Guilherme Corrêa Sereghetti, forestry engineer and coordinator of the CAA project. Potential users of the three applications include city governments, universities, electrical utilities, environmental consulting firms, condominium associations, and nongovernmental agencies.
Trained technicians can gather data to feed into the software. But responsibility for analyzing the information and making management decisions falls to biologists, forestry engineers, or agronomists. “Mobile apps facilitate tree inspection by technicians and the storage of collected data,” says Brazolin.
One of Arbio’s distinguishing features, according to Brazolin, is its ability to analyze the risk of a tree falling. “The software has a model for calculating probability, devised by the IPT,” he says. “A series of data is plugged into the program, such as tree and crown size, trunk diameter, and state of deterioration, like rotting or holes in the trunk. Using biomechanical concepts, the software performs mathematical calculations to ascertain fall probability at 12 different wind speeds and then generates a graph of the results.” To produce the graph, total tree height has to be measured with a device called a hypsometer; crown spread can be determined by measuring the projection on the ground with a tape measure. Based on this information, Arbio calculates estimated crown area, which is applied in the structural model for fall risk.
Phenological data on plants, such as leaf-drop, flowering, and fruiting times, along with information on pests or disease, can also be uploaded to the software. “Our program will allow the public to take part. People will be able to request that a tree be pruned or cut or ask that an unregistered specimen be logged; they can even send in a cellphone photo,” says Sereghetti.
The three applications are at different stages of development and none is in commercial use yet. Work on Arbio began in 2013, and it is already poised for use. Located in the São Paulo Metropolitan Region, Mauá, population 457,000, will become the first town to adopt it in the coming months. “The design of this software was the result of a training program to enhance forestry management, funded by the São Paulo state government,” says Brazolin. “The IPT is considering offering it free to municipalities in São Paulo State.”
Mauá will make Arbio part of its Master Plan in Urban Forestation, drawing on R$2 million from the General Interest Fund of the São Paulo State Department of Justice and Citizenship Defense. The objective is to keep the city’s database on trees current, ensure suitable plantings, and prune trees properly to avoid leaving them misshapen. The city government has a biologist, two forestry engineers, and an agronomist to operate Arbio and also plans to hire one more biologist and another agronomist, along with additional staff, like inspectors and environmental technicians.
The city of São Paulo’s Municipal Department of Green Spaces and the Environment relies on an old system designed by the IPT in 2004, called the Urban Tree Management System (SISGAU). According to the department, the state capital boasts around 652,000 trees, which are monitored using data furnished by agronomists from local governments in the region. SISGAU is employed to log data on geographic, phytosanitary, and management interventions over the life of each tree. Brazolin, who helped develop SISGAU, says the application lacks certain features built into Arbio, like forecasting or managing tree falls.
Geosite was launched in November 2016. “A number of city governments and an energy utility are testing it right now, as a proof of concept,” says Silva. Development of the CAA program began in November 2016 and the first prototype is currently being finalized. Both systems will be marketed soon, but their prices have yet to be defined.
Similar systems are already up and running abroad. One example is the ArbomapWeb, developed in Spain by the firm Tecnigral and utilized in cities like Madrid and Cordoba. By integrating geo-referenced operations involving inventory, management, and incidents, the software program plans, manages, and tracks the urban forest. For $164 a month, the web-based system OpenTreeMap, designed in the United States, can be used to develop urban forestation projects. It was designed by a pool of companies, with a grant from the USDA’s Small Business Innovation Research (SBIR) program. In addition to the tree inventory and photos by site, the application calculates urban forest benefits for the city, such as lowered levels of carbon dioxide (CO2, one of the greenhouse gases); improved air quality; and reduced stormwater runoff. It is used in several countries besides the United States, including the United Kingdom, Mexico, and Portugal.
Biologist Marcos Buckeridge, of the USP Biosciences Institute (IB-USP), who studies urban forestation, says that the system used to monitor New York’s urban forest, called the New York City Street Tree Map, is one of the most advanced in the world. “They have good mapping of each and every tree and a mechanism for calculating benefits to the city,” he says. The software estimates the financial value that each tree returns to society based on such indicators as stormwater interception, removal of air pollutants, and reduction in CO2 and other pollutants.
In Buckeridge’s opinion, a good first step would be to incorporate forestry planning more seriously and scientifically in future plans for a city like São Paulo. He points out that cities will always display artificial features. “But they can at least try to be more integrated into the biosphere than they are today,” he says.
Rich Internet Application (RIA) System for urban forestry planning and management (No. 14/50612-5); Grant Mechanism Innovative Research in Small Business (PIPE); Principal Investigator Guilherme Corrêa Sereghetti (CAA Tecnologia da Informação); Investment R$119,187.40.