Soil compaction is a type of soil degradation that can lead to erosion and poor crop production. Compaction occurs when soil particles are compressed, which limits the size of space available for air and water. Soil compaction can prevent water from getting into the soil and disrupt water and nutrient uptake by the crop. It can also impede crop emergence and root penetration. All of these things can negatively impact yield, but soil compaction is manageable. High-resolution aerial imagery can help growers diagnose and amend areas with compacted soil, allowing them to restore optimum conditions needed for plants to reach their full yield potential.
Identifying soil compaction
To address soil compaction issues, you first need to identify the problem. Soil compaction causes poor plant growth, but so do a number of other factors. Making soil amendments based on inaccurate compaction diagnosis can have adverse effects. High-resolution aerial imagery reveals faint signs of soil compaction that are difficult to read from the ground. Equipment patterns are easily identified from an aerial perspective. Various image types such as thermal, NDVI, color, and infrared images, each offer unique insights and enable growers to make accurate diagnosis’ and effective fixes. Soil compaction can happen at various times of the year, caused by many possible factors. Careful remote and in-field observations can help growers diagnose and address compaction issues.
Infrared and color imagery
Bare soil color and infrared imagery can reveal subtle signs of soil compaction before a crop is planted. Hard pan is a type of soil compaction caused by tillage that occurs in subsurface soil, just below the depth of where tillage happened. Hard pan occurs when soils are cultivated repeatedly at the same depth. Color and infrared imagery make it easy to identify equipment traffic patterns that are prone to soil compaction.
Color and infrared imagery can also reveal patterns that reflect fluctuating soil makeup. Certain soil types are more prone to compaction than others. The image to the right shows a color and infrared image of a field that has a severe soil compaction issue in the lower quarter of the field. While soil compaction diagnoses are generally not made with imagery alone, imagery can help you identify areas that appear prone to compaction to target for scouting. Scouting and compaction testing will confirm the presumed compaction diagnosis. After a soil compaction diagnosis is confirmed, growers can use their imagery to develop short-term solutions and long-term management practices to avoid compaction issues in the future.
NDVI imagery exposes crop stress that results from compaction issues. Historical imagery can help growers identify reoccurring patterns of poor crop growth in the same area of the field from year to year. A high-resolution aerial perspective can also help growers determine if there are spatial patterns to the crop growth that correlate to equipment traffic patterns. In the image to the left, the south half of the field is suffering from soil compaction. Equipment traffic patterns are running horizontally across the lower half of the field that appears to correlate to poor crop performance and a severely compacted area in the bottom quarter of the field that was not cultivated. While it is challenging to make in-season adjustments to address soil compaction that has already affected crop vigor, NDVI imagery can help you accurately identify compacted for off-season soil amendments.
Thermal imagery can help growers identify areas prone to soil compaction due to excessive moisture. Thermal imagery will reveal areas where there is standing water or over-saturated soil prone to compaction. In the image to the right, the lower quarter of the field shows a cool (black/grey) zone that indicates a moisture saturated area, that contributed along with other factors to a soil compaction issue. Over-saturated soil observations made using thermal imagery can also be supported by color imagery, which will frequently exhibit signs of over-saturated soil that appear darker in color compared to soil that is holding a more appropriate amount of moisture. Combined with in-field scouting and color imagery, thermal imagery can help you identify over-saturate parts of your field to target for amendments before a crop is planted, allowing growers to avoid crop loss.
TerrAvion’s color, infrared, NDVI, and thermal image layers all provide easy-to-read indicators of soil compaction issues. Each layer adds a different level of context to any given compaction issues that allow growers to quickly identify issues and narrow down the list of possible causes. Being able to identify soil compaction issues quickly provides growers with the opportunity to address the problems before they affect their yield results and bottom line. For more information on using aerial imagery to manage soil compaction issues, please fill out the form below.