Despite the latest rains, received in Catalonia as a ray of hope against the drought, the situation remains critical. The fallen water is not filtering as it should because the earth is so dry that it does not allow it to enter and works as a raincoat, causing the risk of flooding or torrents to increase if the rainfall is intense.
And this has a direct impact on the trees that “have lost their leaves and even their roots and it will cost them a lot to recover”, as explained by Anna Sanitjas, Director General of Forests and Environmental Management of the Department of Climate Action of the Government of Catalonia .
In this photographic report accompanied by images from La Vanguardia’s Readers’ Photos, with snapshots by Miquel del Río and Josep Soldevila, you can see the consequence of the water deficit suffered by the Catalan forests. “In the last three years it has rained half as much as usual,” says Sanitjas.
The prolonged drought is bringing the vegetation of the Catalan forests to a state of alert for mortality. Moianès, Osona and Bages are the three regions most affected in Catalonia by an increase in the decline of the forest mass. It is estimated that 1 out of every 10 trees in these areas would be seriously affected by water stress, according to data from the Department of Climate Action, Food and Rural Agenda of the Government of Catalonia.
The month of February this year broke the record with the driest vegetation ever. Among the species most affected by the lack of water are the oak, the white pine, the bushes or the red pine. The latter as the most affected, in a serious health situation due to the filtration of pathogens that kill the tree and with a good part of the pine crowns brown, due to the lack of water and the increase in temperatures, which means that they do not occur. the ideal weather conditions for their survival. “62% of trees in 2023 suffered serious defoliation, a considerable increase compared to 2020,” says Anna Sanitjas.
In response, the Center for Ecological Research and Forestry Applications (CREAF) is carrying out a study called Deboscat, which analyzes the impact of drought and climate change on the behavior of trees.
Sampling is done and the state of health of the forest is assessed: where the phenomenon of forest decay, defoliation and discoloration is occurring.
This is how Mireia Banqué, CREAF researcher, describes it: “If in September we find trees with brown leaves, it is not because it is autumn and that is when the leaves become wilted and fall from the tree, but because they have suffered water stress. And the first strategies that the tree has to adapt to less water is by losing its leaves.”
On the other hand, the Government is also working on a project called 8x8CAT, which monitors how trees respond to water deficit and defoliation.
One of the conclusions of this study is that not only does the red pine now have the highest mortality rate among Catalan forest species, but the white pine, typical of the Mediterranean landscape and more resistant to lack of water, is also dying. .
Proof of this are masses of white pines that have collapsed due to water stress and have died, especially in the Garraf Natural Park area. “This has never been seen before. Suddenly an entire forest has died, because it can’t hold out any longer,” says Sanitjas.
Precisely, the forests on the outskirts of Barcelona are the most affected by the lack of rain. Specifically, the Parc de la Collserola, the Parc de la Serralada de Marina and the Parc de la Serralada Litoral are the ones that have the highest rate of drought impact in the province of Barcelona, ??according to the forest vulnerability map of the Network of Parks of the Provincial Council of Barcelona.
Forest management actions and strategies are being carried out in both the Barcelona Provincial Council and the Government, with the aim of avoiding fires and making trees more resistant to episodes of extreme drought.
“Much of the impact occurs in forests that have never had any management,” explains Joan Rovira, natural spaces and green infrastructure technician at the Barcelona Provincial Council. For many years the forests were abandoned but, since 2022, when the symptoms of decline in the forest masses became more acute, forest management was reactivated. In response, the Government’s Climate Action Department has increased the budget allocated to forest treatment by three this year. “The vaccine against forest drought is forest management and fire prevention,” says Sanitjas.
The lack of forest management for so many years has had to do with the different priorities of the governments in previous legislatures and economic viability, as explained by Anna Sanitjas, who recognizes that previously the Catalan Administration did not place forest management as an priority focus and that more physical and economic resources should have been allocated to keep the forests clean and avoid reaching the current situation: “This was not done, we are thirty years behind in the country’s forest management. We have rectified it and now we are betting on it. Even so, it is still insufficient and this long-term commitment is necessary to reverse the situation or address it for the climate of the future.”
And how is the treatment of the forests being carried out? The steps that are mainly being taken are the felling of dead trees, which affect the growth of those around them and which are also invaded by the borer, an insect that enters the bark of the tree and kills it.
“Our work from the DIBA Xarxa de Parcs is to adapt forests to climate change. The number of trees in a forest must be balanced with the resources they have, and this is done, for example, by recovering extensive livestock farming,” says Joan Rovira.
The Department of Climate Action was forced to reinforce and double the staff of the GEPIF, the Special Forest Fire Prevention Groups, in February, four months earlier than usual, before next summer’s fire campaign. The purpose is to increase staff coverage throughout the Catalan territory and carry out forest management and anticipation tasks for what is expected to be “the most complicated summer of the last decade, since the accumulated drought and the increasing number of trees Dead people are fuel for the forest to burn easily”, says Jordi Terrades, director of BOSCAT.
The presence of the GEPIF distributed throughout the territory during the hours of greatest risk will allow it to act more efficiently and quickly in the event of a first intervention due to a fire. “The presence on the ground of the GEPIF is very important to attack the fires as soon as possible and prevent them from spreading,” says Jordi Terrades.
In addition, during the month of May, specific surveillance will be carried out in the riparian forests to prevent the undergrowth from burning and action will be taken in those areas where poplar blob accumulates, which is very flammable. “The more fragile the forest is, the more prone it is to fires,” says Terrades. All this adds up to a critical moment for the nesting of the species.
The fauna is also affected by the increase in temperature and the mortality of the forests, since they depend directly on their ecosystem. This has a special impact on the native fauna, which is harmed by the appearance of invasive species, more adapted to the changes in temperature and humidity that occur in the forests. This causes the populations of native animals to reduce or become endangered, with the effect of unbalancing the food web.
“According to various data analyzed from the last 15 years, dating up to 2020, it shows that biodiversity trends in Catalonia are negative,” explains Cinta Golorons, conservation project technician at the Grup d’Estudi i Protecció dels Ecosistemes Catalans, GEPEC. “For example, butterflies have decreased by 44%. Even so, there are some that benefit from climate change because they are adapted to more anthropic environments,” she clarifies, emphasizing the current situation in which invasive species are gaining ground on native specimens.
The bat is one of the species that plays a substantial role in the balance of the ecosystem and that is now in danger, as Golorons comments: “It is estimated that a bat eats insects equivalent to its total weight every night, this It ranges from species of moths to mosquitoes. If they disappear, there is no longer anyone who preys on these insects and populations increase, resulting in pests, counterproductive especially for agriculture.”
The anomalous high temperatures in winter have affected the natural reproduction cycle of the species, causing many to lay eggs earlier than usual and when a cold wave arrived in spring it has killed these species. This not only affects aquatic animals, which need water to lay their eggs, but also terrestrial animals, which go to lakes or rivers to feed and hydrate their litter.
“Due to the lack of water, the species that serve as prey and food for others are not born, they cannot reproduce either, they become dehydrated… And that shakes the entire food chain,” says Golorons.
