Use sound monitoring to save the rainforest

It is urgent to protect the rainforest

Rainforest plays a very important role in climate regulation. As we all know, water on the surface of land and sea evaporates into water vapor. After the water vapor rises to a certain height, it liquefies into small water droplets when cold. These small water droplets form a cloud, and they collide with each other in the cloud and merge into large water droplets. When it was so heavy that the air couldn’t hold it, it fell from the cloud and formed rain. In Brazil, 70% of the water vapor that constitutes rainwater actually comes from the Amazon rainforest-it evaporates 20 billion tons of water into the atmosphere every day, and the Biasama River (the largest river in the world) discharges 17 billion tons of water into the sea every day. need more.

The humid climate in the rainforest zone guarantees the rapid growth of plants and makes it a living bio-ecological zone in which more than half of the animals and plants on the planet live. However, in the past 100 years, tropical and temperate rainforests have suffered extensive deforestation and destruction by humans. The rainforests that once covered 14% of the earth’s land surface are now only 6%. The area covered by rainforests around the world is still shrinking. And disappear quickly, the species living in it are facing the danger of extinction due to loss of habitat, and biodiversity is seriously threatened.

Illegal logging is one of the main causes of rainforest disappearance. Unauthorized cutting and destruction of rainforests will pose a serious threat to climate change and wildlife. Therefore, how to contain and combat illegal logging has become a major problem in saving tropical rainforests.

Rainforest Fighter

In the summer of 2011, Topher White came to the rainforest of Borneo Island, Indonesia as a volunteer to protect animals. When he first entered the depths of the rainforest, the sound of hornbills, the buzzing cicadas, and the long gibbons of the gibbons all opened his eyes. He was deeply impressed by the complex sounds of the rainforest creatures.

To this end, he collected the sound of the rain forest and made further analysis. But just when he separated different kinds of sounds one by one, he accidentally heard the sound of a chainsaw deep in the jungle in the background sound, which is really shocking, because this place is actually a gibbon protection In the district, not only did the local people spend a lot of energy to protect the rainforest, but also three full-time forest rangers were stationed near this protected area, how could there be loggers?

A few days later, Topher came to this rainforest again. During a 5-minute walk, he happened to meet someone who was sawing down a tree. Although it is only a few hundred meters away from the forest protection station, the rangers do not hear the sound of the chainsaw, because the sounds of the forest itself cover up the sound of the chainsaw one after another, which looks incredible, but it is indeed in the dense rain forest happened.

In fact, other rainforests have similar situations. In order to protect the rainforest, a limited number of rangers often travel through the rainforest. They need to overcome many inconveniences caused by the natural environment, spend a lot of time and physical energy to patrol around, and aimlessly find thieves. However, the effect of this exhausting work is very unsatisfactory. It is really unpredictable to rely solely on manpower to find and stop logging operations, and fight guerrilla warfare with piracy.

How to accurately find and stop illegal logging? This is a practical issue before various rainforest countries.

Loggers in the rainforest

The working principle of the system conceived by Topher

Someone thought about using satellite monitoring and other high-tech technologies to solve this problem. But in fact, when you are in the rain forests of developing countries, you will find that the method is simple, practical, and easy to promote on a large scale.

Turning waste into treasure

Topher White, who has a degree in physics and engineering, thinks about this problem from an engineer’s perspective: If you want to build a system to prevent illegal logging at a low cost, you must first help rangers know what is happening in the forest.

Tove found that this rain forest has a good mobile phone signal. Can it be monitored using a mobile phone device and a program to analyze the sound in the forest? After the device detects the sound of a chainsaw, it automatically triggers an alarm and informs the ranger of the accurate address? ? Just do it. In the system conceived by Topher, the moment the sound of the chainsaw in the forest is heard, the device will capture the sound of the chainsaw and issue a warning to the local ranger through the existing standard GSM mobile phone network. Rangers can immediately appear to stop illegal logging.

Discarded old phone

Forest “alarm” designed by Topher White and its manufacturing

However, there are certain challenges in implementing this project: how to collect and transmit sound data under the environment of high temperature, high humidity and no fixed power supply? Redesigning a device is certainly expensive, so he thought of one of the cheapest and fastest methods-old phones. If the device on the tree is an old mobile phone, the cost will become quite low-because the sound sensor in the mobile phone can be used directly to listen to the sound of the forest without redesigning. In addition, hundreds of millions of old mobile phones are discarded worldwide every year, and turning waste into treasure is the best way to dispose of old mobile phones.

Tofer designed a mobile phone protection box according to the wet and humid climate of the rainforest. To solve the charging problem, he designed a unique solar charging panel at home (this is also a by-product of the remaining materials recovered in the industrial production process), so that the device can be under the canopy Through solar power generation, all devices can be used continuously, without having to be brought back to the base for frequent charging.

From a distance, this device is quite unremarkable under the canopy, but they can receive the sound of a chainsaw as far as 1,000 meters, and the range can cover about 3 square kilometers. After the first beta version was completed, Topher took it to a gibbon sanctuary in Indonesia, which was frequently hacked and felled. The day after installation, the device received the sound of a chainsaw illegally felled and immediately issued The first email. Receiving this warning email, Topher immediately set off to stop the loggers. The arrival of him and his companions surprised the wood thieves, after all, they had never been found before.

This successful practice convinced Topher that this simple system is feasible. Once the notification time is shortened, it can be stopped in time when the logging truck enters the forest area or when the sound of sawing sounds, which greatly reduces the patrol ranger. Costs and risks. Soon, this matter was uploaded on the Internet. People from all over the world consulted via e-mail and telephone, hoping to install this “alarm” as well.

Equipment hanging on the tree

Upgraded Guardian

After communicating with many rainforest management organizations around the world, Tove confirmed that there are actually mobile phone signals in many areas around the rainforest that are plagued by thieves. What is more surprising is that environmental protection organizations around the world and some environmentally conscious people People are willing to provide him with an old mobile phone for free to transform the device.

Platforms and challenges

Topher thinks that the version he originally designed is not really a high-tech solution, but is based on local materials. By thinking with engineer thinking, he believes that even without a mobile phone, there will always be enough things for people to construct similar solutions and play a good role in the new environment.

In order to continuously improve this equipment and serve more rainforests, Tove established a non-profit government organization-Rainforest Connection (RFCx) Rainforest Protection Organization. He recycles old mobile phones in large quantities and upgrades existing equipment. At the same time, with the increase of equipment and more and more complicated projects, RFCx also faces many technical challenges. For example, how to safely and efficiently store and manage these huge and growing data on the back-end platform? How to analyze these data in real time and quickly, and accurately inform the location of the log record… Facing such a huge data management and algorithm optimization, we must adopt systematic technical support to enhance innovative solutions, but this obviously exceeds this The capacity of non-governmental organizations, so some technology companies, such as Google (Google) and Huawei, also began to participate.

Some RFCx projects have collaborated with Google to analyze audio data in real time, identify the sounds related to felling such as trucks and chainsaws, and at the same time understand the behavior of rainforest creatures through sound records; RFCx has developed a set of solar-powered devices with Huawei mobile phone equipment as the core The rainforest monitoring system is called “Guardian”. These guards are scattered throughout the rainforest, able to maintain 24 hours of uninterrupted calls in extreme environments such as high temperature, high humidity, and scorching rain, thereby monitoring the dense and complicated sounds in the tropical rainforest, and transmitting the data to the cloud in real time. In the server. Once the monitoring system finds abnormal sounds of illegal logging, such as the sound of a chain saw or truck, it will push the specific illegal logging location to the local rangers at the first time to help them quickly search. In addition, RFCx is also working closely with Huawei to develop an innovative platform that includes acquisition equipment, storage services, and intelligent analysis. It uses the system’s artificial intelligence technology to help understand the sound of animals, thereby providing assistance to endangered animals.

New advances brought by artificial intelligence

Spider monkey in Costa Rican rainforest

Today, RFCx is using better technologies to help protect the rainforest.

For the recording data that RFCx has collected for many years, Huawei helped adjust the accuracy of the chainsaw monitoring model in these data. For example, in the early version, according to the feedback from the rainforest organization, the sound of mosquitoes was often misreported as the sound of a chainsaw, and it was difficult for the human ear to distinguish these two sounds. For this type of false positive data, RFCx began to use mosquito sound data to retrain the model. After repeated testing and refining, the latest model application can detect 96% of chainsaw incidents. With the continuous improvement and optimization of the model, fewer false alarms occur.

With the help of AI technology, the same technology can be used to quickly distinguish the sounds of chainsaws, birds and other animals. The study of sounds is a new scientific tool. Biologists and ecologists can use this system on many occasions, whether it’s in inaccessible rainforests or parks in London, and even Topher has disclosed some requests to use the device to monitor gunfire in the city, or Used to track illegal fishing vessels.

In addition, in the Costa Rican rainforest project, in addition to logging, endangered species such as spider monkeys have become another research object. Huawei and RFCx have built a spider monkey language intelligent analysis model, which uses AI technology to recognize its calls and send accurate positioning in real time.

In order to better protect the rainforest, we have adopted various practical measures and technologies, but this is far from enough, and it requires the attention and participation of the government, enterprises and the public.