Constructed wetlands are in use to improve the quality of contaminated groundwaters at many sites in the USA. Target contaminants include both organic and inorganic constituents. Volatile and nonvolatile hydrocarbons are found in ground water at closed petroleum refinery sites, and in leachates from landfills. Polycyclic aromatic hydrocarbons are pollutants at many sites. Chlorinated organics o...

Particles were isolated from soil leachates from the genetic horizons of a subalpine Podzol from the central Cascades, Washington. Organic particles containing traces of aluminum, iron, silicon, and sulfur were predominant in the migrant material through the upper horizons (horizons A + B); their movement was arrested in the B2hir horizon. Below B2hir and at depth, phyllosilicates, quartz, and ...

The effect of leachates of different phenological stages of Cassia occidentalis L. on Parthenium hysterophorus L. was studied. Seed germination, radicle length, plumule length and fresh and dry weight of Parthenium were recorded. Pigments and protein contents were also measured to evaluate relation between biochemical and biophysical parameters of Parthenium under stress. The leaf leachate of C...

The complexation reaction between metal cations o f different valence states (Al, Bi(III), Cr(III), Fe(III); Ca, Co(II), Cu(II), Mn(II), Ni(II), Pb(II), Zn; Na) and fulvic acids is investi­ gated by the streaming current detection technique. It can be shown that the metal complexa­ tion capacity does not only depend on the nature o f the cation but also on the origin o f fulvic acids, which wer...

The isotopic composition of mercury (Hg) was determined in cinnabar ore, mine-waste calcine (retorted ore), and leachates obtained from water leaching experiments of calcine from two large Hg mining districts in the U.S. This study is the first to report significant mass-dependent Hg isotopic fractionation between cinnabar ore and resultant calcine. Data indicate that delta202Hg values relative...

Oil shale ash contains mineral ingredients of agricultural importance and could be used for treatment of soils. However, the ash contains several hazardous ingredients, i.e. toxic trace metals which could be mobile and create environmental concerns. Beneficial use of the oil shale ash in agriculture and forestry requires better knowledge of leaching characteristics of soil-ash systems. In this ...

BACKGROUND AND AIMS Is the release of allelochemicals by the dominant tussock grass Festuca paniculata responsible for its dominance by inhibiting growth of neighbour grasses in subalpine grasslands? As such a community is also structured by mowing practices, what could be the impact of mowing on allelopathy? METHODS A design was used that isolated allelopathy from resource competition by sep...