When created, approximately 4,000 years ago, irrigation was carried out on crops through the transposition of water from rivers, what we know today as furrow irrigation. However, when ancient farmers migrated to wetter regions, agriculture and irrigation followed different paths.

Brought by the Portuguese in 1533, sugar cane had its greatest development in the state of São Paulo, a state that to this day occupies first place in the national classification of this crop. It is located mainly in the Ribeirão Preto and Piracicaba mesoregions, which are characterized by soils with high fertility, water retention and good rainfall distribution.

With the growing demand for ethanol and sugar, the sector was forced to explore new regions such as Oeste Paulista, Minas Gerais, Goiás and Mato Grosso, where there are changes in the scenario, as these regions, in addition to having soils with less water retention, they still have more aggressive climates, characterized by more concentrated rainfall. As a result, it was observed that the agricultural productivity of sugarcane fields suffered a significant drop, going from 82 tons per hectare to 70 tons per hectare in a matter of years.

In this way, the sector arrived at a logical thought: “If I need a certain amount of sugarcane to serve my industry and the production calculation is productivity times the harvested area (Ton of Sugarcane per Hectare times hectare), we can conclude that the best method to increase my production is to acquire more land”. And that is how sugarcane cultivation became an extension culture.

But this solution was temporary, as, with the appreciation of land, increased production costs and climate anomalies, it was not possible to guarantee the stability of annual production, often leaving the industry idle. If we analyze the main factors that lead to productivity, we observe that 50% is the responsibility of the climate, in which the volume and distribution of rainfall are the variables with the greatest impact.

However, I'm not talking about climate anomalies, but rather a normal rainy season, in which, out of the 12 months of the year, it rains 6 months and the other 6 months we have drought. And as the sugarcane field is cultivated for at least 12 months, we conclude that at least 46% of the sugarcane cycle is developed under drought. And, if we decide to include anomalies, this number could get even worse.

To mitigate the “normal” poor distribution of rainfall, the sector saw the need to return to an ancient past and began the adoption of large-scale irrigation systems. There are several irrigation systems on the market, each with its own characteristics, being essential for each type of situation. But I would like to highlight drip irrigation, as it is considered the newest irrigation (created in 1965) and the most efficient in the concept of using water for production.

Drip irrigation applies water directly to the root region, at high frequency and low intensity of application, through emitters known as drippers, aiming to compensate for the plant's water deficiency. With this system, a humid zone is formed within the soil known as a wet bulb, and as these wet bulbs overlap, a damp strip is formed along the drip line, hence the name localized irrigation. And, because the dripper pipes are buried, the loss effects such as water evaporation, umbrella effect and water drift due to wind force are practically zero.

Due to these characteristics, sugarcane plants and producers that adopt this drip irrigation system have begun to observe several benefits, with reduced production costs, environmental gains (decarbonization credits) and verticalization of production. The verticalization of production, or rather, the increase in production in the same unit of area (hectare), leads producers to reduce their planted areas and, even so, maintain their production. Let's do some calculations to illustrate. If you need to produce, for example, 100,000 tons and have a productivity of 80 tons per hectare, you will have to own (acquire or lease) 1,250 hectares.

However, if you adopt irrigation and increase productivity to 150 tons per hectare, only 667 hectares will be needed. And, just remembering, it's not just the area, but also the cost to produce that matters. Continuing with the same calculations, without the need for leasing (estimated at 2,431.97 reais per hectare for 2024), the cost of sugarcane production is approximately 13,000 reais per hectare per year. In other words, by reducing the planted area, without losing production, in the simulated case, we saved more than 8 million reais per year to produce the same 100,000 tons.

As a practical example, in the state of Mato Grosso, a producer acquired 450 hectares of drip irrigation, with the aim of increasing his productivity, fulfilling his contract with the plant and leaving more area to produce grains, his main crop. Furthermore, the drip system evolved for other purposes, not only to provide water and nutrients (fertigation) to plants, but also as an environmental tool for production and cost reduction. New techniques for applying vinasse are being used, and among them I highlight the use of vinasse as a fertilizer, applied through the drip irrigation system. Due to the fact that the dripper pipes are buried at an approximate depth of 0.30 meters, when vinasse is applied, this product is also applied deeply, thus avoiding contact with human beings, dissemination of unpleasant odor and proliferation of flies, such as stable fly (Stomoxys calcitrans), meeting all the requirements of environmental regulatory bodies.

In a recent study, greenhouse gas emissions were compared in the drip irrigation system and in the rainfed system. In this study, it was proven that, with the use of dripping, it was possible to reduce carbon dioxide emissions into the atmosphere by 52%, where it is noted that the main impactful reductions are in the change in land use, diesel oil and correctives.

Due to its high uniformity of application, several studies on the application of chemical and biological products for the most varied crop needs have been tested for application via drip. In addition to the excellent agronomic results, due to the fact that the drippers are in the subsurface, there is no contact between chemicals and beneficial biota, such as, for example, pollinators or natural enemies of the main pests. Recently, Ibama issued a technical opinion on the application of Thiamethoxam through aerial spraying (Final Technical Opinion, SEI Ibama 17732614), due to the risk of harm to pollinators, something that does not occur when the application method is buried.