Alarm for the appearance of large amounts of algae in the Mar Menor

The Mar Menor asks for help again.

On this occasion, the alarm has been caused by the rapid growth of algae known as angel hair (

mixed with ovas (another type of algae) in various areas, including La Manga del Mar Menor.

This plant appears when there is an excess of nitrogen in the water, which is caused in the lagoon by the discharges that arrive through different streams, loaded with the remains of the fertilizers used in agriculture.

The latest measurements indicate that "very high values" of nitrogen are entering, around 21,000 kilos per day, Emilio Mariadolores, president of the scientific committee that monitors the lagoon, warned today at a press conference called by the Murcian Government (PP). made up of politicians and experts.

This alarming situation "marks the beginning of eutrophication", which if it is not stopped will probably mean that "the situation is the same or worse than last year".

The strip of algae detected in the La Manga area is located about 100 meters from the coast and is about two kilometers long and an average of about 50 meters wide, the Platform for the Mar Menor has calculated.

The regional government has been removing the algae for more than three weeks, the only method that exists to prevent it from decomposing on the shores, forming a slime that moves and that, with the appearance of phytoplankton (composed of microscopic organisms), leads to a decrease in oxygen.

So far, more than 10,000 tons of biomass and algae have been removed.

Isabel Rubio, member of the platform Pact for the Mar Menor and author of a blog on the biodiversity of the lagoon and the Mediterranean, tells how in February the shores were already clogged by the same algae.

This Tuesday she realized that the situation had become complicated, when she observed a silver stripe in the sea.

“We took a kayak and went to see what it was and we found this, I have no words left to describe the disaster, because I had never seen anything like this in La Manga.

There have been other episodes, but on the lower shore of the Mar Menor, by Los Alcázares and Lo Pagán, closer to where the boulevards discharge, ”she indicates.

Detail of the algae that have grown in the lagoon. Isabel Rubio

The scientific committee points out that the only solution so that the Mar Menor does not reach a point of no return is to reduce the water table of the aquifer that exists in the area and that is between 16 and 17 meters above sea level.

For decades, this body of water has been collecting leaks from farms, with the remains of the fertilizers (nutrients) they use, something that was not mentioned in the press conference.

The lagoon "is a system that the more we feed it, it responds innately by consuming the nutrients."

If solar radiation is added to this, more phytoplankton is produced, the water becomes greener and more macroalgae are born.

At the moment, the oxygen is maintained at good levels, except in two stations located in the center of the Mar Menor, although this situation does not, at the moment, pose any risk to the fish.

An unbalanced and vulnerable ecosystem

Juan Manuel Rodríguez, a scientist at the Spanish Oceanographic Institute and an expert on the lagoon, quarantines the thesis of the regional government and the scientific committee that only acting on the water table would solve the problem, because all the sediment dragging that occurs with the rains.

"Many come from agricultural plots in which the current form of cultivation causes a lack of soil protection," he details.

Keep in mind, he adds, that the lagoon changed from 2016, when it collapsed for the first time, turning into a green soup.

"It became an unbalanced ecosystem and more vulnerable to any climatic or man-made disturbances."

The algae that have appeared are "opportunistic and would not appear if there were no nutrients in the water,

Ángel Pérez Ruzafa, member of the scientific committee and participant in the press conference, has launched a message of "absolute hopelessness", because they "have been saying the same things for six years" the time they have been "linking the situation of eutrophy with the entry of nutrients due to the water table.

Pérez Rufaza has blamed the Ministry for the Ecological Transition for not putting a stop to deterioration, because "agricultural control measures are good and necessary, but not sufficient."

In his opinion, “six years have been lost” to put in place the infrastructure that would allow the water to be redirected, treated and prevented from reaching the sea.

The Minister of the Environment of Murcia, Antonio Luengo Zapata, also present at the press conference, has charged against the Government of Spain, which he considers responsible for not carrying out "any infrastructure" that is needed to put a stop to the water inlet.

"Whoever wants to add, continue working with us and whoever does not want, leave," he said in reference to the ministry.

He also recalled that Murcia offered the department of Teresa Ribera to take on the north collector project to collect water from the boulevards and not enter the Mar Menor, if the State did not want to do so, and that months later they have not received a response.

Luengo has not mentioned that the nutrients have their origin in the agricultural activity of Campo de Cartagena.

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