SDI, Pros and Cons
Take the challenge and suggest your own additions.
The following should be considered potential pro's and cons of subsurface drip irrigation. Some producers might see an aspect as an advantage, while another might see an aspect as a disadvantage. For example, there are opportunities for improved cultural practices with SDI while at the same time there might be less tillage alternatives. For a more detailed look at some proposed advantages, try pointing you browser to http://www.geoflow.com/agriculture/phene.htm
Advantages
More efficient water use
Greater water application uniformity (resulting in better control of the water, nutrients, and salts)
Enhanced plant growth, crop yield and quality
Improved fertilizer and pesticide management
Less water quality hazards
- Less runoff into streams
- Less nutrient & chemical leaching and deep percolation
Limited weed growth and reduced weed germination
Decreased energy costs
Less disease pressure due to drier and less humid crop canopies
Improved cultural practices
Warmer soils possibly aiding in earlier planting or harvest
Field operations can occur during irrigation
Less irrigation equipment exposed to vehicular damage
No soil crusting due to irrigation
Improved double cropping opportunities for some crops and regions
Easy to automate
Less mechanized parts
Less irrigation system corrosion
Improved opportunities for use of some degraded waters
Reduced weather-related application constraints (especially high winds and freezing temperatures)
Increased flexibility in matching field and irrigation system sizes
Well suited to widely spaced crops provided sufficient soil wetting pattern is achieved
Pressure compensating systems not as limited on slopes as surface irrigation
Perhaps less pest damage (rodents, insects, etc. ) than surface drip irrigation
Possibilities for using system for soil fumigation
Possibilities for use in germination, depending on dripline depth, flow rate and soil constraints
Disadvantages
High initial investment cost
Plugging of system
Persistent maintenance requirements
May require more complex water quality management than surface drip irrigation
Operation and management may require more consistent oversight
More design components (ie flush lines, etc.) than surface drip irrigation
Fewer visual indicators of system operation
Cleaning water through filtration required
Subsurface repairs more difficult
Rodent problems more difficult to solve
Shorter design life than alternative irrigation systems
May be less forgiving in design errors than alternative irrigation system
Restricted plant root development
Wetting pattern may be too small on light sandy soils
Surfacing or tunneling of the emitter flow to the soil surface (also called chimney effect)
Possibility of soil ingestion at shutdown if vacuum occurs
System is spatially fixed, so annual crop spacing/ orientation must be carefully matched
May not be suitable for crop germination
Salinity may be increased above dripline, increasing salinity for small germinating crop
Tillage options may be limited
Length of run may be limited
Less developed technology than some alternative irrigation systems
Concerns about waste product (driplines) in subsoil if system is abandoned
Fewer turnkey systems available
Roots from some perennial crops may pinch dripline
Root intrusion into dripline can occur
Compaction around dripline can occur in some soils and depths
I'm sorry but at this point, I can't take the time to explain or argue about any of the items on the list.
However, I do challenge you to send me more advantages and disadvantages as you see them. Ultimately, I will have to decide whether they are appropriate for inclusion or whether they are covered by another item already.
Please click here to email your Additions
A longer article discussing the advantages and disadvantages of SDI was prepared by Lamm in the fall of 2002.
