Ecological recovery of vegetation at a former industrial sludge basin and its implications to phytoremediation

Abstract

Examination of a former industrial sludge basin containing organic pollutants showed that the basin had undergone substantial ecological recovery through natural forces following the removal of surface water in 1982. Conventional phases of ecological recovery (plant invasion and succession) have occurred, but the structure of the biodiverse plant community (51 species and 22 families) was different from that at a recovering non-polluted disturbed site. Three plant species (Bermuda grass, mulberry, and sunflower) believed to be early invaders of the basin still persist in large numbers indicating that these species are well suited to cope with normal environmental stresses at this area (i.e. seasonal drought and flood) as well as organic pollutants. There was an indication that early invaders of the site fostered disappearance of contaminants thereby creating more favorable conditions for a broader spectrum of plants to grow. Vegetation analyses of naturally vegetated hazardous waste sites hold promise as a screening device for identifying plant species and management practices worthy of further phytoremediation investigations.

Effects of different backfill soils on artificial soil quality for cut slope revegetation: Soil structure, soil erosion, moisture retention and soil C stock

“…Forty quadrants (1 m  1 m) were placed randomly on each slope. The plant coverage was measured using the method by Olson and Fletcher (2000). The Margalef index R and ShannonWiener diversity index H 0 were calculated to characterize plant richness and plant diversity, respectively.…”

Screening of Twelve Plant Species for Phytoremediation of Petroleum Hydrocarbon-Contaminated Soil

“…Italian ryegrass, sorghum, maize and alfalfa are recognized as phytoremediators (Radwan et al, 1995;Wiltse et al, 1998;Pradhan et al, 1999;Châineau et al, 2000;Banks et al, 2003b;Parrish et al, 2004). Bermuda grass, sunflower, southern crabgrass and red clover are recognized as hydrocarbon-tolerant plants (Adam and Duncan, 1999;Olson and Fletcher, 2000). These studies suggested that grass species and Leguminosae could be suitable for phytoremediation of petroleum hydrocarbon-contaminated soil.…”

Benefits of Vegetation for Soils with Organic Contaminants

“…An ecological study of this recovering site (Olson and Fletcher 2000) showed that it differs markedly from the recovery pattern and plant diversity at a nearby site that had simply had soil dumped on it. Three plant species, mulberry, sunflower (Helianthus annuus), and Bermuda grass (Cynodon dactylon), were predominant at the sludge basin, while a much wider range of species was important at the other disturbed site.…”