Effects of humic acid doses and aplication times on the plant growth, nutrient and heavy metal contents of lettuce grown on sewage sludge-applied soils

TUFENKCI S. , TURKMEN O., SONMEZ F., ERDINC C. , Sensoy S.

FRESENIUS ENVIRONMENTAL BULLETIN, vol.15, no.4, pp.295-300, 2006 (Journal Indexed in SCI) identifier identifier

  • Publication Type: Article / Article
  • Volume: 15 Issue: 4
  • Publication Date: 2006
  • Title of Journal : FRESENIUS ENVIRONMENTAL BULLETIN
  • Page Numbers: pp.295-300
  • Keywords: humic acid, application dose, application time, heavy metal, nutrient, sewage sludge, COMPOST, SUBSTANCES

Abstract

Effects of increasing doses of humic acid (HA), applied in different periods, on the plant growth, nutrient and heavy metal contents of lettuce grown on sewage sludge-applied soils were investigated. A constant dose of 20% sewage sludge (SS) was added to experimental soil placed in pots. Various doses of HA (0, 500, 1000, and 2000 mg kg(-1)) were applied to the pots for different time periods (0, 30, 60, and 90 days before seedling transplantation).