{
  "eprintid": "392",
  "rev_number": "1",
  "eprint_status": "archive",
  "userid": "159",
  "dir": "disk0/00/00/03/92",
  "datestamp": "2003-01-27",
  "lastmod": "2009-08-20 14:18:47",
  "status_changed": "2009-08-20 14:18:47",
  "type": "journalp",
  "metadata_visibility": "show",
  "item_issues_count": "0",
  "doclang": "en",
  "projects": [
    "da2d1"
  ],
  "fundingpart": "main",
  "refereed": "yes",
  "budget": "0",
  "publicfulltext": "FALSE",
  "creators": [
    {
      "name": {
        "family": "Askegaard",
        "given": "Margrethe"
      },
      "id": ""
    },
    {
      "name": {
        "family": "Eriksen",
        "given": "Jørgen"
      },
      "id": ""
    },
    {
      "name": {
        "family": "Olesen",
        "given": "Jørgen E."
      },
      "id": ""
    }
  ],
  "title": "Exchangeable potassium and potassium balances in organic crop rotations on a coarse sand",
  "ispublished": "pub",
  "subjects": [
    "2farming"
  ],
  "keywords": "Exchangeable potassium, potassium leaching, potassium balance, organic farming",
  "abstract": "Crops on sandy soils (<5% clay) are exposed to K deficiency due to the small release and high leaching losses of K. Reliable tools are needed to improve the K management in cropping systems with limited K input, such as organic farming where import of nutrients are restricted according to the EC regulations. We investigated K balances and exchangeable K (Kexch) changes in an organic crop rotation experiment. Potassium leaching decreased from 42 kg ha-1 in 1998/99 to 21 kg ha-1 in 2000/01 as an average of a crop rotation (spring barley, grass-clover, winter wheat and pea/barley) with manure application and without catch crops. In the same period, spring Kexch decreased from 5.0 to 3.0 mg K 100 g-1 soil (0-20 cm). The retention of the straw K left in the field after harvest increased with decreasing levels of Kexch. The cereal crops did not respond to K application but in the pea/barley mixture the pea yield increased by 46%. The concordance between measured K balances and changes in Kexch was weak. Exchangeable K is suitable as a tool for K management on a crop rotational basis, and a Kexch above 3 mg 100 g-1 soil in the autumn should be avoided to minimize K leaching.",
  "date": "2003",
  "date_type": "published",
  "publication": "Soil Use and Management",
  "number": "19",
  "full_text_status": "restricted",
  "pagerange": "96-113",
  "documents": [
    {
      "docid": "1348",
      "rev_number": "1",
      "eprintid": "392",
      "pos": "1",
      "format": "application/pdf",
      "language": "en",
      "security": "staffonly",
      "main": "AEO2003.pdf",
      "files": [
        {
          "filename": "AEO2003.pdf",
          "filesize": "247537",
          "url": "http://orgprints.org/392/1/AEO2003.pdf"
        }
      ]
    }
  ]
}