土壤壓緊測試儀可以幫助您了解土層是否緊實以及土層的深度。儀器有兩個：一個直徑1.27cm，另一個1.91cm。
Soil compaction can occur in any type of soil. Years of traffic and tillage can cause soil particles to group together and fill in air spaces in the soil creating a “plow pan” below the tillage area. When this happens, a hard layer is formed making it difficult for moisture and roots to pen-etrate the soil.Some soil types are more susceptible to compaction than others; but once a compaction layer is formed, and moisture and traffic continues, the compaction layer will continue to get denser and thicker.
| TYPICAL COMPACTION | ||||
| SITUATION | ||||
| Disc Depth | 8 cm | |||
| Abnormal Root | 45 kg | |||
| Development | 23 cm | Uncompacted | ||
| Plough Depth | ||||
| Plough Pan | Roots Cannot | Moisture is | 38 cm | 180 kg |
| Trapped Above | ||||
| Penetrate | Compacted | |||
| and Below | ||||
| Subsoiling Depth | 34 kg | |||
| Uncompacted | ||||
WHAT ARE THE IMPACTS OF A SOIL COMPACTION PROBLEM?
1. Compacted soil is much harder to work. This will cause you to use more power and take longer to till, wasting fuel, time and money.
2. You may already be aware of soil compaction but not have the tools to determine if it is a problem. For example, unnecessarily trying to correct soil compaction by tilling to a deeper depth can be a waste of time and money.
3. Your crop yield can be reduced by as much as 50% because of poor root and plant development.
4. Compacted soil can prevent water from penetrating deeper into the soil. This can reduce plant development and yield especially during dry periods with no rain. Compaction can also lead to surface water retention making the field more difficult to work in the spring and fall seasons.
5. In compacted soil, fertilizers, pesticides and herbicides can more eas-ily be washed away and not absorbed or even become more concen-trated causing plant damage. This can result in reduced crop yield.
WHAT TO DO ABOUT A SOIL COMPACTION PROBLEM?
If you have determined that you have a soil compaction problem and at what depth the compaction exists, your solution could be as easy as one of the following:
• Reducing traffic in the affected areas of the field.
• Seeding cover crops that will improve water management.
• Choosing a tillage tool that will penetrate the compacted area of the field.
Your local agricultural extension office is a good source of information to help you determine what can be done to help correct and prevent soil compaction problems.
WHAT IS A SOIL COMPACTION TESTER?
Your Soil Compaction Tester is a penetrometer which measures the com-paction of soil and is based on the ASAE S313.3 standard. The tester is supplied with two tips: a small tip (1/2” diameter) for use in firm soil and a large tip (3/4”diameter) for use in soft soil. The dial has two scales (one for each tip) that are calibrated in pounds per square inch of the base area of the cone shaped tip.
THE DIAL IS COLOR-CODED FOR REFERENCE:
Green (0 - 200 psi) / 0-14 kg/cm2
Good Growing Conditions
Yellow (200 - 300 psi) / 14-21 kg/cm2
Fair Growing Conditions
Red (300 psi and above) / 21 kg/cm2 and above
Poor Growing Conditions
