Drought, rivers without flow, locusts: monocultures

Drought, rivers without flow, locusts: monocultures

An intense drought threatens not only soybean crops and their transport down the great downspout of the Paraná, the 2nd largest river in South America, but now an invasion of locusts adds a new challenge. Sketches of the future based on deforestation and agrochemicals.

The news is of a major locust invasion in the northeastern part of Argentina, they arrived from Paraguay and are now heading to Brazil, advancing about 150 kilometers a day. Invasions that had not been known for decades in Argentina, with the eradication of the plague in 1953. But they “mysteriously” returned in 2015. In the same way that they “returned” in Africa and Asia due to an excess of rains in the Omani desert, which provided the conditions for their spread. In the latter case, the established cause is climate change.

Climate change created unprecedented conditions for locusts to breed in the generally barren desert of the Arabian Gulf, experts say, and the insects were then able to spread through Yemen threatening the food security of 10 million people.

For now, this association with climate change is tepid in the south of the globe. An area increasingly deforested to use these lands for soy monoculture. With many interests so that the consequences of industrial agriculture, the use of agrochemicals and their impact on biodiversity are not seen.

But the Argentine media is already beginning to make the connection: “As for how a "cloud" like this is established, one of the most important reasons is the climatic factor: the hot and dry climate facilitates its formation. Another reason is the elimination of the natural enemies of locusts, such as birds, frogs, fungi and bacteria, partly explained by the improper use of insecticides“.

And let's not forget: deforestation emits CO2 and is a key factor in warming and, like agrochemicals, destroys biodiversity.

The “good news” is that when the lobsters arrive in Brazil they will not have much to eat due to the lack of rainfall in the area, given that the drought affecting the Brazilian state of Rio Grande do Sul has caused the loss of more of half of the soybean crop and 40% of the corn, crops that make the state the third largest producer of grains in Brazil. The calculation is that the losses in the entire chain, including the food industry and others related to the field, reach 6,700 million dollars. We will see how much damage is added by insects.

These unprecedented droughts have the second longest river in South America, which usually carries a colossal flow of 16,000 m3 per second, the Paraná River, with the worst downspout in 50 years. About 75 million people live in the Paraná-Paraguay basin. It encompasses the most urbanized area of ​​South America and its population grows at the rate of approximately one million inhabitants per year. In it are several of the most populated cities of the subcontinent, such as São Paulo, Buenos Aires, Curitiba, Campinas and Rosario.

So much so that they have had to install supplementary pumps to provide drinking water to one of the largest cities in Argentina: Rosario. In April, the height of the river in said city was 0.4 meters, the lowest figure since 1971, and without antecedents for April since the records began in 1884. For reference, the minimum draft to guarantee the passage of ships is 2.47mts. The inability to navigate is also causing serious economic losses to the area's export sector, the soybean complex.

The situation improved somewhat in June, Paraná had 1 meter at the height of Rosario, after having touched 8 centimeters the previous two weeks. The entry of ships to the ports of Gran Rosario increased, but the tons loaded fell. But the problem with drinking water is not an isolated case, in the province of Chaco drinking water decreased by 25% and in other points auxiliary pumps have had to be installed to provide drinking water, such as in Concordia and Santa Fe.

"For more than six months, some sectors of northern Argentina have been experiencing a rainfall deficit. It is raining very little, both in the country's provinces, such as Paraguay, and southern Brazil. In some sectors there are extreme drought conditions, ”said Cindy Fernández, from the Argentine National Meteorological Service.

Climate change again

The engineer Juan Borus, from the National Water Institute (INA) of Argentina detailed some of the issues that explain the current moment. "We are beginning to get used to the tremendous climate variability, I think it is reasonable to associate it with climate change, the clearest manifestation is this variability, which makes us go from situations of very little to situations of a lot and vice versa," he said.

“This situation has been brewing since last year, it began in the Paraguay River, in Formosa we had a decrease from April to November of more than 8 meters. The water level dropped that during that entire time, the most persistent in history. It is fluctuating in low waters, the contribution is minimal and it adds (the problems of the) upper Paraná basin, which for the third consecutive year has no seasonal rise in summer and has little participation from the Iguazú River, which is the one that saves us already sometimes punishes us. It is incredible what happens in Cataratas, with flows of 200 cubic meters when we had 1600 ”, he highlighted.

Likewise, he said that it is a downspout that can occur if a lot of situations converge, which are the ones that are occurring now, all the basins of contribution to the Paraná river are in a situation of low water.

The Natural Resources Research Center, dependent on the INTA, National Institute of Agricultural Technology, pointed out that the fact is extraordinary not only because of the decrease in flow and height, but because of the months of persistence. The Director of this organization, Pablo Mercuri, explained that the consequences will be felt in the coastal ecosystem of the entire Paraná, and will affect biodiversity. "Many times what happens after these prolonged downspout processes is the appearance of invasive plant species”, He expressed.

As stated by the National Water Institute, the future evolution of the levels in this section of the river will depend strongly on the spatial distribution and amounts of rainfall. The meteorological perspectives are not favorable, expecting a persistence of days with limited or scarce rains. In fact, according to the Weather Service, “there is no indication of a noticeable change in the regional climate trend in the quarter ending August 31”.

We recently published a report that showed that up to 6 overlapping impacts of climate change would overlap on human populations in the next century. This that we narrate is a clear example.

In the most basic sense, the conclusion of this myriad of events happening at the same time is that we build a system that devours itself. We thought that deforesting and planting soybeans was the solution to the economic backwardness of South America. And sadly you keep thinking. More soy is more deforestation, more warming, more agrochemicals, less biodiversity, fewer birds and insects to combat pests, which ultimately make any production unviable. Somehow nature regulates itself. It sets the limits that we are unable to impose on ourselves blinded by extreme greed. Even putting the very food security of humanity at stake.

Source: Clima Terra

Video: Somalia suffers desert locust outbreak adding to climate misery (October 2020).