Drought. When the water no longer flows

For weeks now, the drought has been putting France a little more torment every day. Men, animals, soils try to stand up. Plants also try to survive, in their own way. “In times of drought, they keep as much water as possible for themselves.explains Paul Galzin, beekeeper near Béziers (Hérault). As a result, flowering is reduced; and on the flowers that come out anyway, the plant closes its nectar glands. There are flowers, but no nectar. » However, nectar, a kind of sweet juice, has the function of attracting pollinators. To sum up: no nectar, no honey.

Or at least much less. “My summer harvest, on chestnut and heather, has just endedcontinues the beekeeper. It is divided by four compared to last year. However, it represents two thirds of my annual production. So even though the spring harvest was very good, it represents a drop of around 40% over the year. » And it does not stop there : “Honey is the colonies’ energy reserve for the winter. And pollen, their protein reserve, even more necessary for the renewal of generations. » In other words, it is only this winter that we will be able to measure the impact of the drought on the colonies of bees themselves – when they are already suffering the impact of pesticides and parasites.

The flow of the Loire divided by four

As for any other breeding, there are solutions: keep part of the honey for the winter or add invert sugar (a mixture of glucose and fructose which comes in the form of a white paste). But they all have a financial impact which comes on top of others, such as the price of diesel – a heavy item when you have to visit hives scattered within a radius of 60 km around Béziers. “I am organic, which further increases the costsanalyzes Paul Galzin. So, seasons like this, we should not chain two or three. The increase in the selling price has its limits, consumers will not be able to follow forever. » And in the long term, “When we look at Spain or the Maghreb countries, we see that honey yields are falling. We will have to adapt”he concludes, specifying that he wants » to stay positive « .

Adapt? In the immediate future, the thing seems difficult. Everywhere, the signs are red, like the dominant color of the drought decree maps that the prefectures publish every week. Two-thirds of metropolitan departments (62 out of 96) are officially in crisis. This month of July was the driest since temperature records have existed (1958). The rivers disappear from the landscape or experience starving flows, like the Loire: the royal river saw its own almost quartered (from 475 to 129 m3 / s) between the beginning and the end of July. The soils are drier than during the – already historic – precedents of 1976 and 2003. Adapt? Even in the mountain pastures, where the grass is always abundant and very green, the herds no longer find anything to graze. Milk production is falling, and breeders are already beginning to attack the hay reserves that they have just mowed and which, in normal times, are used for them to spend the winter.

Adapt? On his farm located between Dreux and Châteauneuf-en-Thymerais, in the north-west of Eure-et-Loir, Xavier Pelé has only been forced to stop all irrigation since Friday August 5. Until then, in this department which relies on the vast resources of the Beauce aquifer, it could still irrigate – with strong technical and time constraints – part of its crops. As a result, his plots show very disparate yields: between 60 and 100 quintals per hectare, which is not catastrophic according to him. Insured against drought risk, he will not use this very expensive insurance this year: “The drop in yield must be greater than 25%. »

The « mega basins » at the heart of criticism

However, he did not wait for this red-hot summer to reflect on the question… and on his practices. When many point to the cultivation of corn, which is very water-intensive in the middle of summer, he manages to grow it without irrigation. Nothing miraculous: “I work the soil as little as possible. As a result, it stays fresh, it dries out less. And since my soil remains alive, rich in microbial organisms and earthworms, when it rains, the water does not run off and penetrates much better. » He is inexhaustible – without bad puns – on the subject: “Many farmers have become aware of the limits of our environment and the impact of our activities, he pleads. We seek to minimize this impact. » Hence the interest in no-till practices and cultivation on plant cover, which make it possible to « develop the life of the soil, therefore improve drainage and better recharge the water table when it rains, with better quality water, because it is filtered by the soil ». In this way, on his land, he has « gained in ten years 1 point more organic matter ». Now, 1 point, he translates, « it’s 200m3 more water per hectare in the soil ».

Adapt? This soil practitioner joins the experts: “Making water reservoirs by pumping in the groundwater does not make sense. » This is called setting foot in megabasins, this method of storage demanded by some irrigators but highly criticized, both in terms of the evaporation it causes and in terms of sharing the resource. » But we could better manage the resource, completes Xavier Pelé.For example, storing wastewater downstream of treatment plants, instead of discharging it into rivers as is done today. » A point on which France, which recycles less than 1% of its wastewater (0.6%), lags behind neighbors such as Italy (8%) or Spain (14%). A waste to which is added that of the distribution networks, whose poor condition leads to losses by leakage of up to 20%, equivalent to the annual consumption of 18.5 million people. So there are solutions. It will still be necessary to gain their implementation. In the meantime, according to Météo France, the aquifers will not recharge before this fall, and it would still take a month of excess rain for that. Until then, we will have to hold on.


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