With cows grazing in a vast meadow surrounded by wire fencing, and with farmers checking to see how their livestock were faring under a scorching sun, it looked like a classic pastoral scene set on what was surely land dedicated to agriculture.

But the cows and the farmers were actually guests in a nature preserve, one where both were welcome — with some stringent restrictions.

As Europe looks for ways to balance what can be the competing demands of limiting the effects of extreme weather with producing enough affordable food, the Doode Bemde nature preserve, its supporters say, shows an innovative way to work toward achieving both goals.

The idea for this preserve, set in an unassuming corner of Flanders, the Dutch-speaking region of Belgium, was dreamed up in the 1980s by a group of idealistic conservationists who came to the local village of Neerijse with a daunting task: convincing farmers to sell their land, which provided both their income and their sense of identity.

The farmers’ initial reaction was “not good,” said Piet De Becker, one of those conservationists. “If you say, ‘Give me your land,’ they become angry.”

Expecting such resistance, the conservationists were ready with the idea of a hybrid approach. If the farmers would agree to sell their land, they would be allowed to use the nature preserve, but with conditions: They could let their cows graze there. They could continue to farm specific plots. And they could cut grass to make hay — but only at specific times. They would also have to swear off pesticides and use only natural fertilizer.

Gilbert Vanderveken, a fourth-generation farmer, was the first to sell in 1986, parting with 10 acres of his family’s land where they had farmed beets, chicory, wheat and corn. Mr. Vanderveken was joined by 11 other farmers over the ensuing years, and that land contributed to the creation of the 815-acre Doode Bemde preserve.

Although the preserve was initially conceived as a project to foster the area’s biodiversity, it has come to play a crucial role in limiting the catastrophic floods that for centuries plagued the nearby city of Leuven and its roughly 100,000 people.

When powerful rains ravaged Belgium and Germany in the summer of 2021, leaving at least 240 people dead, Leuven was spared. When the Dijle River overflowed its banks, it flooded into the nature preserve, which acted as a buffer zone and retained the water for three days, saving the city, through which the river runs, from a deluge.

This victory, experts say, most likely would not have happened without the unique partnership between conservationists and farmers that made the preserve possible.

“This nature preserve really has been a pioneer,” said Gert Verstraeten, a professor at KU Leuven, a university in the city, and an expert in water management. “People have been fighting over centuries against water, and now suddenly we have to acknowledge that if there really is a lot of water in the river system, you cannot stop it. So it’s better to give back the space to the rivers.”

If more space elsewhere in Europe is going to be given back, then similar hybrid approaches might be one of the more effective models to follow, as the land adjoining rivers in rural areas is often occupied by the continent’s farms — and by politically powerful farmers, who might otherwise be reluctant to part with their plots.

Agriculture has played an important role in the European Union since its creation, and the bloc provides farmers with billions of euros in subsidies every year to ensure that cheap food is available to all Europeans.

But in recent years, in the face of an increasing number of extreme weather events tied to climate change, the priority has started shifting from producing food to embracing ambitious environmental policies, including cutting greenhouse gas emissions, restoring natural areas and limiting the use of pesticides.

And it has become clear to policymakers that if the bloc wants to achieve climate neutrality by 2050, agriculture will have to change. In July, E.U. lawmakers approved a bill that would require member countries to restore large swaths of damaged natural habitats within their borders, angering farmers, who recently protested outside the European Parliament in Strasbourg, France.

While the Doode Bemde nature preserve offers a blueprint for reconciling agriculture and nature, it also reveals some of the limitations of such coexistence.

Mr. De Becker, the conservationist, called the preserve “a win-win” model, but he conceded it came with drawbacks for the farmers.

The preserve’s retention of water can alleviate the effects of droughts, but the cyclical flooding that now occurs makes much of it unsuitable for farming. And the agricultural work that does get done is less efficient than it once was, with farmers allowed access to only certain plots at certain times.

“They get less profit per hour of work,” Mr. De Becker said.

There had also been some hope that the partnership would win converts from more traditional farming practices. But of the 12 farmers, only one over the past 40 years has switched to organic farming. The others, including Mr. Vanderveken, continue farming outside the preserve using pesticides and nonorganic fertilizers.

Mr. Vanderveken said that he did not think there was any “value added” by the E.U.’s green policies. But his two sons, who want to take over the family farm and over 300 cows he owns, have different opinions. “I am old school; they are new school,” he said.

And he does not begrudge them their opinions. “We have to adapt,” he said. “Things move on.”

Michel Frisque, the lone organic farmer, studied agricultural engineering in the 1970s and said he saw the negative effects that traditional farming had on his beloved nature. He rebelled against his traditionalist father, and he now farms apples and pears, and breeds cows and sheeps to be able to fertilize the orchards, making his operation entirely self-sufficient, he said.

But Mr. Frisque does not blame his neighboring farmers or those across Europe for not following his path, which brings enough profit for him to make a living but is not, he said, an adequate way to feed the world’s population, at least if people “want to eat 500 grams of meat every day.”

“We have 60 years of bad agriculture policy,” Mr. Frisque said. “But it’s important to say, that’s not the fault of the farmers. The consumer needs cheap food, and policy encouraged that.”

In his view, what people eat, and how much, will need to be a part of any long-term solution.

“You have to change your consumption habits a little bit,” he said.