Evaluation of composts and liming materials in the phytostabilization of a mine soil using perennial ryegrass

Abstract

A microcosm experiment was carried out to evaluate the effects of municipal solid waste compost (MSWC) or garden waste compost (GWC), and liming materials in the rehabilitation of a soil affected by mining activities, and to study the use of perennial ryegrass (Lolium perenne L.) for phystostabilization. The performance of the amendments was assessed by soil chemical parameters, total and bioavailable metals (Cu, Pb and Zn), soil enzymatic activities, and plant relative growth and mineral composition. In general, both composts corrected soil acidity and increased the total organic matter content of the soil, although with a better performance in the case of MSWC, especially when considering total N and available P and K levels in the amended soil. The application of both composts and liming materials led to a decrease in the mobile fractions of Cu, Pb and Zn, but mobilisable fractions of Cu and Zn increased with MSWC application. Plant biomass increased more than three times in the presence of 50 Mg MSWC ha(-1) and with the combined use of 25 or 50 Mg MSWC ha(-1) and CaO, but no significant differences were observed when GWC was applied. Plant tissue analysis showed that the treatments did not significantly reduce Cu, Pb and Zn uptake by the plant. Dehydrogenase, and the enzymes related to the N-cycle, urease and protease, had increased activities with increasing MSWC application rate. Conversely, the enzymatic activities of both enzymes related to the C-cycle, cellulase and beta-glucosidase, were only positively affected by GWC application, a compost obtained from raw materials rich in C. Principal component analyses evidenced this clear separation between the effect of MSWC on soil enzymes related to the N-cycle and of GWC on soil enzymes related to the C-cycle. This study indicates that MSWC (50 Mg ha(-1), limed or unlimed) can be used successfully in the remediation of a highly acidic metal-contaminated soil, allowing the establishment of perennial ryegrass.

Microbial community structure and biomass of a mine soil with different organic and inorganic treatments and native plants

“…These are promising alternative technologies to traditional options of excavations and ex situ treatment, offering an advantage of being non-invasive and low cost. The purpose of revegetation is to stabilize the site, by providing a cover crop that will prevent dispersion of metalcontaminated particles by water and wind erosion and reduce metal mobility by rhizosphere-induced adsorption and precipitation processes (Alvarenga et al, 2008). However, plant growth is very limited in mine contaminated soils (high levels of metals and metalloids, soil acidity, low C and nutrients availability) and soil amendments such as lime, organic residues and industrial products such as zeolites and insoluble polyacrylate polymers promote the establishment of a vegetation cover by providing essential nutrients for plant growth, raising the pH, and chelating toxic metals (Alvarenga et al, 2008;2014;Guiwei et al, 2008;de Varennes et al, 2010;Pinto et al, 2015).…”

“…Most studies concerning the rehabilitation of polluted soils in situ have focused on the effects of different treatment on bioavailability of trace elements and plant growth (Alvarenga et al, 2008;Pérez-López et al, 2008), but interventions at one level inherently affect the restoration attributes at other levels (Kardold and Wardle, 2010). During decades, links between above-ground changes and belowground activities carried out by soil microorganisms were often ignored, although they are determinant of ecosystem resilience and functional efficiency, and they can assist restoration ecology (Kardold and Wardle, 2010).…”

Pilot Scale Use of Compost Combined with Sorbents to Phytostabilize Ni-Contaminated Soil Using Lolium perenne L.

“…An analogical situation was observed when adding a mixture of compost from food waste and halloysite, although its influence was weaker. Alvarenga et al [65] found that the application of both composts and liming materials led to a decrease in the level of mobile/effectively bioavailable fractions of heavy metals.…”

Amendment application in a multi-contaminated mine soil: effects on soil enzymatic activities and ecotoxicological characteristics

“…However, procedures can be adapted to soils, using leachates extracted with water, in order to assess the impact of soil composition on ground water (Loureiro et al 2005;Alvarenga et al 2008a). Vibrio fischeri bioassays have demonstrated to be sensitive to heavy metals and can detect acute and sublethal effects caused by a large number of chemicals (Ribo and Kaiser, 1983).…”

“…Chaîneau et al (2003) and Alvarenga et al (2008a) found that bioassays with V. fischeri and plant growth were very sensitive indicators, being more reliable to evaluate the reduction of adverse effects caused by toxicants than other bioassays, such as earthworm survival or seed germination. In the current study, although plant biomass was higher in 'Fe+PM' than in the 'NA' treatments, bioassays showed that this amendment addition does not create suitable conditions to the organisms assayed.…”