Site-specific potassium application based on the fertilizer potassium availability index of soil

Site-specific potassium application based on the fertilizer potassium availability index of soil Soil varies in its potassium (K+) content and ability to supply K+ to crops. Site-specific K+ management aims to optimize crop production and minimize K+ loss from the soil. The spatial variation of available K+ prior to fertilizer application, the K+ fixation capacity of soil and soil texture need to be taken into account for variable-rate K+ application. This study was done to measure the spatial variation of the fertilizer K+ availability index (AI), which shows the potential for K+ fixation, and to develop a strategy that takes the spatial distribution of this index into account for site-specific K+ application. To determine the fixation capacity, the linear relation between the amount of K+ added to soil and the amount of K+ fixed was determined on 40 topsoil samples. Samples of soil were equilibrated in a moist condition for 3 weeks after the addition of 0, 25, 75, 225 and 675 mg K+ kg−1. The increase in exchangeable K+ was described by a linear relationship. The fertilizer K+ availability index (slope) varied from 0.20 to 0.49, indicating 51–80% of added K+ was converted to the non-exchangeable form. Principal component analysis (PCA) showed that the first two components accounted for most of the variation, 48.7 and 26.3% of total variation, respectively. A non-hierarchical cluster analysis (k-means clustering) identified four groups and the amounts of fertilizer K+ required were calculated for each group. The results suggested that such classes could form a basis for variable-rate application to maintain an adequate K+ status for crop production and to reduce potential K+ loss from soil by leaching. Precision Agriculture Springer Journals

Site-specific potassium application based on the fertilizer potassium availability index of soil

Loading next page...
Springer US
Copyright © 2007 by Springer Science+Business Media, LLC
Life Sciences; Agriculture; Soil Science & Conservation; Remote Sensing/Photogrammetry; Statistics for Engineering, Physics, Computer Science, Chemistry and Earth Sciences; Atmospheric Sciences
Publisher site
See Article on Publisher Site


You’re reading a free preview. Subscribe to read the entire article.

DeepDyve is your
personal research library

It’s your single place to instantly
discover and read the research
that matters to you.

Enjoy affordable access to
over 12 million articles from more than
10,000 peer-reviewed journals.

All for just $49/month

Explore the DeepDyve Library

Unlimited reading

Read as many articles as you need. Full articles with original layout, charts and figures. Read online, from anywhere.

Stay up to date

Keep up with your field with Personalized Recommendations and Follow Journals to get automatic updates.

Organize your research

It’s easy to organize your research with our built-in tools.

Your journals are on DeepDyve

Read from thousands of the leading scholarly journals from SpringerNature, Elsevier, Wiley-Blackwell, Oxford University Press and more.

All the latest content is available, no embargo periods.

See the journals in your area

Monthly Plan

  • Read unlimited articles
  • Personalized recommendations
  • No expiration
  • Print 20 pages per month
  • 20% off on PDF purchases
  • Organize your research
  • Get updates on your journals and topic searches


Start Free Trial

14-day Free Trial

Best Deal — 39% off

Annual Plan

  • All the features of the Professional Plan, but for 39% off!
  • Billed annually
  • No expiration
  • For the normal price of 10 articles elsewhere, you get one full year of unlimited access to articles.



billed annually
Start Free Trial

14-day Free Trial