The Effects of Water on Soil Compaction

Water as a Cause of Soil Compaction

• Along with insufficient crop rotation, traffic from large machinery passing above and tillage, rainwater is thought to be one of the primary causes of soil compaction. Rainwater that collects near the top layer of soil can form into a dense crust through which seedlings cannot sprout. Typically, soil compaction due to rainwater can be resolved with simple tillage. However, when combined with other causal factors of compaction, the problem can be more complex to resolve.

Drainage

• The biggest water-related problem associated with soil compaction is that compacted soils tend to be very poorly drained. A soil's drainage is principally defined by how porous the soil is. Compaction presses soil particles together, thereby reducing the number of pores in soils and reducing drainage. Soil drainage is an important factor when growing any plants. The compacted layer of soil is also unable to take on new moisture from uncompacted layers.

Water Loss

• The effects of soil compaction are not all negative. A slightly compacted soil can suspend water in soils that would otherwise be too dry to support seed germination. Compaction can also leave seeds in closer and prolonged contact with the soil particles from which the seeds obtain precious nutrients. These two effects of soil compaction can lead to improved seed germination, but they only occur in soils that are lightly rather than heavily compacted.

Other Considerations

• Soil compaction tends to be a more common problem in an agricultural rather than a home gardening setting, if only because the use heavy of farming equipment tends to contribute to soil compaction. However, if you frequently face problems related to soil compaction in your home garden, consult a local university extension office as to the possible causes and treatments for your soil compaction problems.