Identifying and managing compacted agricultural soils is essential for proper rooting and plant nutrition, impacting crop productivity.
Every farmer knows that their greatest asset is their land. And when we talk about it, as important as the number of hectares is the productivity of those soils. After all, having thousands of hectares of gullies would be of no use, wouldn't it?
But unlike the huge erosion craters easily identifiable by sight, another soil problem as detrimental as gullies is much more difficult to diagnose: agricultural soil compaction.
Being hidden a few centimeters below the surface, compaction requires precision agriculture techniques and tools for its identification and to develop the most appropriate management plan to solve it.
To help you understand a little more about soil compaction and its effects on crops, we at Falker Agricultural Automation have prepared this article.
Here you will see:
How does agricultural soil compaction occur?
How does compacted soil impact agriculture?
How to diagnose a compacted soil?
How to solve agricultural soil compaction?
The best tool for detecting soil compaction
And if you want to delve even deeper into the topic, download our ebook, “Soil Compaction Monitoring Guide”.
Have a good read!
What is soil compaction?
The term "soil compaction" is widely used in both the engineering and construction sectors as well as in agriculture, albeit with opposite objectives.
While in civil construction the goal is to compact the soil to serve as support for a structure that will be built on top, in agriculture the purpose is precisely the opposite: to loosen the soil to facilitate root development of plants for better nutrient absorption and higher productivity.
Of course, for the purposes of this article, we will focus on the definition and effects of soil compaction for agriculture.
As explained by the Agropós blog, "soil compaction is the increase in soil density and the reduction of its porosity, which occurs when it is subjected to high stress or continuous pressure."
How does agricultural soil compaction occur?
The compaction of agricultural soils occurs basically due to two factors: natural field accommodation over time, from direct planting, without ever having had soil management beyond its surface; and, primarily, from improper agricultural use, with heavy machinery or even animal overload, which end up pressing the soil due to gravity.
In Brazil, direct planting has been widely disseminated and adopted on a large scale for over 50 years. It is responsible for numerous benefits to producers and the environment, such as reduced production costs and decreased erosion and loss of nutrients dragged by rainwater to lower parts of the terrain.
However, when direct planting is poorly done, the soil naturally accommodates. Consequently, it leads to compaction - also increased by the overweight of agricultural machinery that is often used inappropriately in very humid soils.
A very wet soil contracts when pressed too much, becoming flattened. When it dries, it does not return to its previous density and porosity,
How does compacted soil impact agriculture?
As we observed, incorrect soil management is the main factor that causes compaction in the field. In addition, a compacted soil has less capacity for plant development.
According to the Embrapa Cerrados study, "Soil Compaction: consequences for plant development," authored by agricultural engineers Marco Aurélio Carolino de Sá and João de Deus Gomes dos Santos Júnior, "the factors that directly affect plant growth are water content, oxygen diffusion rate, temperature, and mechanical resistance that the soil offers to seedling emergence and root growth, the latter directly related to the degree of soil compaction." (p.10).
Compaction reduces water infiltration, causing leaching - the movement of materials due to the effect of water that runs off and generates erosion or the water that infiltrates the soil towards the water table. In other words, rain does not infiltrate compacted soil, causing rapids to reach the lowest areas of the land, dragging soil, seeds, nutrients, and everything else.
Another consequence of compacted soil is its reduced aeration capacity, which is its potential to supply oxygen to microorganisms and roots. Coupled with the fact that heavy rain "sweeps" away much of the nutrients, this weakens the health of plants, making them more susceptible to diseases in the root system, leaves, and fruits.
Moreover, not only are the roots less nourished and more susceptible to diseases, but compacted agricultural soil also creates greater resistance to penetration. Without proper root growth, which needs to expend much more energy trying to break through the compacted layers, there is less nutrient absorption and, consequently, a negative impact on plant development, resulting in productivity losses that can reach up to 60%.
How to diagnose a compacted soil?
Usually, the first diagnosis is made empirically, when the producer recognizes compaction when noticing loss of productivity in specific areas of the farm.
However, it is more correct for the producer to anticipate this loss of productivity and diagnose possible areas with compacted soil before it affects the harvest.
In the past, the producer could rely solely on his perception to detect that something was not going well in a certain sector of the crop, diagnosing the problem only when there was already a clear loss of productivity. Now, he can count on the help of important precision agriculture instruments.
In the case of soil compaction, the digital penetrometer is one of the precision agriculture instruments that has become increasingly popular in recent years. Through it, preventive diagnosis of compacted soil has become very simple and practical to do.
The digital penetrometer is easy to use, allows for simplified data reading, and transfer of information to software that enables complete mapping of compacted soil areas in crops.
How to solve agricultural soil compaction?
As our Soil Compaction Monitoring Guide ebook teaches, the use of cover plants with vigorous root systems - such as forage radish and sunn hemp - combined with good soil management practices have the potential to reverse compacted areas.
However, mechanical intervention may be necessary in areas with very high penetration resistance values.
Depending on the depth of compaction, scarification or subsoiling can be performed, always in conjunction with cover plants, which help break up the compacted soil layers.
Moreover, even if mechanical interventions are carried out, studies indicate that the use of cover plants is essential to ensure soil aeration and to prevent re-compaction after management - and worse, with even greater intensity.
The best tool to detect soil compaction
The PentroLOG PLG2040 is Falker's digital soil compaction meter, the best-selling agricultural penetrometer in the world, used by agronomists in more than 40 countries.
The PenetroLOG PLG2040 features integrated GPS for georeferencing data collection, an intuitive graphical display with user-friendly interface, USB input for data transfer, Bluetooth for integration with the app, and a modern, lightweight, and robust design that provides practicality and safety in agricultural handling, allowing its use at any stage of crop development.
Through integration with the Falker Compact App, a system with data stored in the cloud and automatic synchronization between the web and the app, you can access information from anywhere for analysis or sharing, as well as generate comprehensive reports of measurement results for presentation.
Contact our team of experts today to learn more!
