PORTO TOLLE, Italy
Drought and unusually hot weather have increased salinity in Italy’s largest delta, where the mighty Po River meets the Adriatic Sea south of Venice, killing the rice fields along with the shellfish that are a key ingredient in one of Italy’s culinary specialities: spaghetti with mussels.
At least a third of the valuable double mussel mussels farmed in the Po Delta have died. Plants on the banks of the Po River are wilting as they drink water from increasingly saline aquifers, and tributaries have dried up, amphibian and bird wetlands shrinking.
“It is obvious that there is a whole system with an ecology that will have permanent problems,” said Giancarlo Mantovani, director of the Po Basin Authority. The ecosystem includes the Po Delta Park which, together with the neighboring areas in Veneto, forms a reserve recognized by UNESCO for its biodiversity.
The amount of water flowing into the delta from the Po River is at an all-time low, reaching just 95 cubic meters (3,350 cu ft) per second last month due to drought conditions caused by a lack of snow cover in winter and spring and autumn summer rains were caused . That’s a tenth of the annual average. It has been almost two months since farmers were able to tap the river water for agriculture.
The impacts could be even more lasting as saltwater seeps inland distances never before recorded, seeping into aquifers, underground rock strata that can hold water.
And while deltas are, by definition, an area of exchange between freshwater and saltwater, the movement is becoming increasingly one-way: Saltwater intrusion inland has increased from two kilometers (just over a mile) in the 1960s to 10 kilometers (six kilometers). miles) in the 1980s to a staggering 38 kilometers (nearly 24 miles) this year.
“The area around the Po River is three meters below sea level, so saline water continuously flows into the aquifers,” Mantovani said. “We are therefore not only creating an agricultural problem, a human problem, but also an environmental problem. … This is a perfect storm.”
For mussel farmers, excessive salinity, high temperatures, and the resulting spread of algae are suffocating the mollusc that’s at the heart of one of Italy’s favorite summertime dishes: spaghetti alle vongole. And none is more valuable than the vongole veraci with a striped and grooved skin, grown in the Adriatic.
“You can see the shellfish are suffering,” said Katisucia Bellan, who has been collecting shellfish for 27 years. “In the afternoon, with this heat, the lagoon dries up. You can drive past here with the tractor.”
According to Coldiretti’s farming lobby, this year’s die-off could accelerate unless proper salt-freshwater exchanges are restored. She blames a failure to remove sediment from the delta, which allows oxygen and freshwater into the lagoon, to aggravate the situation.
Meanwhile, mussel farmers fear more stocks may die and have rushed to the market while they still have mollusks to sell. This abundance has pushed prices down and created even more economic hardship. “There is a double negative effect: die-off and lower prices,” said Alessandro Faccioli of Coldiretti.
Nearby rice farmers are also watching the rise in salinity with growing concern. The paddy fields of the Po Delta are a small part of Italy’s national rice production, concentrated in drought-stricken Piedmont and Lombardy closer to the source of the Po River. While the larger producers suffer from water shortages in their fields, those in the delta suffer from increased salinity, which kills plants.
Grower Elisa Moretto, who runs a small family business, is hoping to save a third of her harvest this year, but that remains to be seen. Whether she can turn a profit depends on other forces, including increased fuel and fertilizer costs.
But the real concern is for the future, as salinity rises and permanently damages aquifers.
“When that happens, everything dies,” Moretto said.
The Associated Press’s climate and environmental reporting is supported by several private foundations. Learn more about AP’s climate initiative here. The AP is solely responsible for all content.