dimanche 4 janvier 2015

34- Water and irrigation -3- Agroecological case of conscience


Today, to follow with my last post (my best-selling article to date, as by far the most widely read), I will present a situation, real, in which a political decision, a priori justified for reduce water consumption by agriculture, will have, in the short term, deplorable environmental consequences.

One of the farms I manage, placed on the edge of the Guadalquivir, is first bordered, then crossed by a temporary watercourse, what here is called an arroyo, and in North Africa, a wadi. This watercourse is fed from a source that is drying up in the summer, except when the surrounding farms irrigate their fields by gravity, i.e. by a more or less controlled flooding system. This type of irrigation has the feature to always use much more water than crops need.
The water in excess disappear by percolation (filtration through the soil) to the water table, very superficial in this area, or by surface runoff to this small stream, which itself, flows into the Guadalquivir few kilometers away.
This small watercourse has the distinction of having been covered, about 5 km after its source, many years ago, to facilitate the development of the neighboring town.

This little river is finally fed most of the year by the rains between October and May, followed by irrigation surpluses during 4-5 months of almost total absence of rain from mid-May to mid-October, something normal here.
This little paradise, although surrounded by horrific farmers who don't hesitate for a second to use pesticides and fertilizers, has seen the development, over the years, of a peculiar fauna among which there are such spatulas, egrets, storks, herons, coots, martins fishermen, ducks, cormorants, raptors, but also foxes, civets, mongooses, and even a wildlife more difficult to observe snakes, lizards and others, as well as turtles.

These are the indigenous turtles from banks of the Guadalquivir (Emys orbicularis hispanica). Without being an endangered species, at least in the South of Spain, these turtles have a serious problem in recent years, due to the uncontrolled proliferation of Florida's famous turtle (Trachemys scripta elegans), you know, that little brown-green and striped turtle, with red spots on the sides of the head, the one you can buy in pet stores in their little plastic aquariums. Well this American turtle, carnivorous, voracious and prolific, is now considered an invasive species. Its sale is much more controlled in recent years, but still not enough. Many of these turtles were released into lakes and streams in the region, by people who have realized that they bite and grow, and in addition they are often carrying salmonella. They are quickly becoming a serious environmental problem because, being much more aggressive and prolific that indigenous turtles, they are supplanting them gradually.
Many conservation programs have been put in place, especially in nature reserves, including in particular in the Doñana National Park, at the mouth of the Guadalquivir, the largest bird reserve and one of the largest wetlands of Europe. These programs are based on catches of turtles by trapping. Indigenous turtles are released, and Florida's turtles are eliminated, to maintain their populations into tolerable levels.

Let's go back to our little watercourse. Over the years, an ecological equilibrium is set up on this little river. It's very cute, I love to walk beside it, while visiting the orchards, and see waders fly away, frightened by my presence, to land again a few meters away. Turtles live in peace, with no risk of colonization by the terrible Florida turtle, since the watercourse is isolated. It's beautiful, it's bucolic, and it gives me the feeling of not being a horrible polluter, although I use pesticides and fertilizers (wisely).

What is the problem?
Well, simply that, as I told you in my last article, it is necessary (and politically correct) to do freshwater savings.
If Spanish agriculture is dynamic, it's mainly because of the construction, at the time of the Franco dictatorship, of hundreds of dams across the country for rainwater storage. These dams are connected to cities and agricultural areas with a gigantic grid of canals. Have water in summer is not a natural resource here. It is a resource and a wealth created by man for the development of its economy.
Without that, Spain would probably still a poor country, because the development of its agriculture is a pillar of its economic development. Currently, with the terrible crisis that the country is going through for several years, it is the economic sector that is keeping her head above water, with tourism.

So we have to save water. Okay. And for this, buried pipelines infrastructure is being put in place throughout the country, which provides or will provide pressurized water to farmers with water meter for everybody. It is evident that the billing on consumed water volume will spread gradually. Farmers will be therefore urged to reduce their water consumption in order to reduce their bill.
And what will it happen to my little watercourse? It will become temporary again.
The birds will go elsewhere to survive. I don't worry for them, they will find other areas to install. Foxes, civets, snakes and other land animals will have a little more difficulties to relocate, but they are likely to achieve.
By cons, turtles will be condemned, de facto. The river, the current paradise for them, allowing them to live and prosper in peace, will turn into hell without water. Which currently protects them, will kill them. The river is covered on a considerable distance downstream of the farm, and turtles will be unable to overcome this obstacle.
I love watching these turtles, which they should not enjoy watching me as they dive every time they see me. Yet I know that more or less long term, they will disappear from this little river that will become sterile again, for lack of a sufficient amount of water to ensure the conditions for survival of the species that inhabit it, during the 4-to-5-month-long Andalusian summer.

This is the chronicle of a death foretold. How many similar situations are there in the world? Certainly thousands.
So we must save fresh water? Yes of course, but attention to environmental consequences.
Nature is a delicate balance, and I think about it, we all agree.
But conceiving Nature without agriculture, is also conceiving a planet without human beings.

So take great care to under-reasoned policy decisions.
Agriculture is an integral part of the ecological balance.
Reduce fresh water consumption is also condemning certain balances to change, so some sensitive species, such as turtles, to disappear. It also condemns whole regions or even whole countries to the depletion of its biodiversity. Indeed, the creation of these dams and canals, and the water supply, even in summer, of all these small streams throughout the country have significantly improved the ecological situation in Spain, bringing new areas for biodiversity, new nesting areas, in short, a strong enrichment of fauna and flora.
The drastic reduction of water consumption in agriculture will result, among others, in a sudden ecological regress, and a likely acceleration of desertification in Spain, so profoundly negative environmental consequences.
Saving water does it justify taking such a risk?
Is there any other ways to get similar results with less environmental cost? Can we generate or store fresh water in large amounts, in order to preserve both the production of food and all ecosystems that depend of it?
This is the case of conscience of the day.

It's not possible to do political ecology without including agriculture and, like it or not, modern agriculture, vibrant and productive.
Because during this time, the world population continues to rise inexorably.

Then let's work together for an ever more environmentally friendly agriculture, respecting the health of workers and consumers, saving water, just enough, equitable and productive.

Aucun commentaire:

Enregistrer un commentaire