Root growth patterns of two nitrogen-fixing trees under landfill conditions

Yuk Sing Gilbert Chan

Research output: Journal article publicationJournal articleAcademic researchpeer-review

1 Citation (Scopus)


The root growth patterns of two N2-fixing trees: Acacia confusa, Casuarina equisetifolia, in two completed landfill sites and two control sites were studied. The topsoils of the four sites were compacted by machinery (bulk density 1.5 to 2.2 g cm-3) and no additional plant medium was added for tree growth. Both Acacia confusa and Casuarina equisetifolia had shallow root plates in all four sites. Their roots were mostly confined to the upper 15 cm of topsoil and did not penetrate further down. Dehydrogenase activities were high in the upper 15 cm of topsoil and low at deeper levels. Nitrogen fixing activities were found only in the upper 15 cm of topsoil. These two species of tree showed they were suited to grow on completed landfill sites, to fix nitrogen under landfill conditions and the 1 m thick landfill cap is unlikely to be damaged by the growth of their root plates.
Original languageEnglish
Pages (from-to)55-62
Number of pages8
JournalLand Contamination and Reclamation
Issue number1
Publication statusPublished - 26 Nov 1997
Externally publishedYes


  • nitrogen-fixation
  • restoration ecology
  • root penetration
  • sanitary landfill
  • woody plants

ASJC Scopus subject areas

  • Geotechnical Engineering and Engineering Geology
  • Water Science and Technology
  • Environmental Science(all)

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