New network tracks the health of trees across Czechia’s forests

Since 2016, scientists have been installing special sensors at various sites throughout Czechia. So far, they’ve set up 185 such stations. One of them is located in a forest near Popovice in southern Moravia.

At the heart of each station is a metal post embedded in the ground. This post collects and transmits data from a variety of sensors. At the Popovice site, for instance, a dendrometer is strapped to a nearby tree. Jan Krejza from the Czech Academy of Sciences’ Global Change Research Institute explains how it works:

“The dendrometer shows us how the trunk is pulsating by means of a metal band that encircles it, where during the day the trunk is mainly shrinking by the evaporation of the water from the leaves, and conversely at night the water is replenished and the actual wood cells are formed.”

The dendrometer measures these tiny movements to within a thousandth of a millimetre, giving researchers insight into the tree’s condition. Researchers also track air humidity, temperature, and sunlight. On top of that, samples are taken from the trees to be examined in a lab.

All this data feeds into a system known as the DendroNetwork. Tomáš Rebok from Masaryk University’s Institute of Computer Science explains what the black dots on a map of Czechia represent:

“The black dots, of which there are 185, are individual stations that send us data twice a day, which we then process on our servers. We can click on the individual points to see how the forests or even specific species are doing in that station. For example, whether they have enough water or how fast they are growing.”

Another map – this one colour-coded – shows the condition of entire forest areas. The colours represent the status of various environmental factors, as Mr. Rebok describes:

“Blue typically shows a problem-free state, while red shows some critical value that needs to be addressed. The data is stored so we can also look at the long-term trend.”

According to Jan Krejza, the system of monitoring stations is mainly designed for use by foresters and government agencies.

“The advantage of the whole system is mainly in the speed and accuracy of the sensors. They collect data every half an hour. While traditional methods of collecting this type of data took place at 5 to 10 year intervals, a person had to come and manually measure the tree or visually assess its condition.”

Scientists say the network is now dense enough to effectively monitor Czechia’s forests. The next step is to team up with partners abroad – and eventually build a network that covers the whole of Europe.