Advances in Phytoremediation

Dietz, Annette C.; Schnoor, Jerald L.

doi:10.2307/3434854

Cited by 100 publications

(106 citation statements)

References 19 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The concept of vegetation as a tool for contaminant mitigation (phytoremediation) is not new (Dietz and Schnoor 2001). Many studies have evaluated the use of wetland plants to mitigate pollutants such as road runoff, metals, dairy wastes, and even municipal wastes (Vymazal 1990;Brix 1994;Cooper et al 1995;Kadlec et al 2000).…”

Section: State Of the Art: Artificial Wetlands As Nonpoint-source Polmentioning

confidence: 97%

Mitigation of agricultural nonpoint-source pesticide pollution in artificial wetland ecosystems

et al. 2008

View full text Add to dashboard Cite

International audienceContamination caused by pesticides in agriculture is a source of environmental poor water quality in some of the European Union countries. Without treatment or targeted mitigation, this pollution is diffused in the environment. Pesticides and some metabolites are of increasing concern because of their potential impacts on the environment, wildlife and human health. Within the context of the European Union (EU) water framework directive context to promote low pesticide-input farming and best management practices, the EU LIFE project ArtWET assessed the efficiency of ecological bioengineering methods using different artificial wetland (AW) prototypes throughout Europe. We optimized physical and biological processes to mitigate agricultural nonpoint-source pesticide pollution in artificial wetland ecosystems. Mitigation solutions were implemented at full-scale demonstration and experimental sites. We tested various bioremediation methods at seven experimental sites. These sites involved (1) experimental prototypes, such as vegetated ditches, a forest microcosm and 12 wetland mesocosms, and (2) demonstration prototypes: vegetated ditches, three detention ponds enhanced with technology of constructed wetlands, an outdoor bioreactor and a biomassbed. This set up provides a variety of hydrologic conditions, with some systems permanently flooded and others temporarily flooded. It also allowed to study the processes both in field and controlled conditions. In order to compare the efficiency of the wetlands, mass balances at the inlet and outlet of the artificial wetland will be used, taking into account the partition of the studied compound in water, sediments, plants, and suspended solids. The literature background necessary to harmonize the interdisciplinary work is reviewed here and the theoretical framework regarding pesticide removal mechanisms in artificial wetland is discussed. The development and the implementation of innovative approaches concerning various water quality sampling strategies for pesticide load estimates during flood, specific biological endpoints, innovative bioprocess applied to herbicide and copper mitigation to enhance the pesticide retention time within the artificial wetland, fate and transport using a 2D mixed hybrid finite element model are introduced. These future results will be useful to optimize hydraulic functioning, e.g., pesticide resident time, and biogeochemical conditions, e.g., dissipation, inside the artificial wetlands. Hydraulic retention times are generally too low to allow an optimized adsorption on sediment and organic materials accumulated in artificial wetlands. Absorption by plants is not either effective. The control of the hydraulic design and the use of adsorbing materials can be useful to increase the pesticides residence time and the contact between pesticides and biocatalyzers. Pesticide fluxes can be reduced by 50-80% when hydraulic pathways in artificial wetlands are optimized by increasing ten times the retention time, by recirculation of w...

show abstract

Section: State Of the Art: Artificial Wetlands As Nonpoint-source Polmentioning

confidence: 97%

Mitigation of agricultural nonpoint-source pesticide pollution in artificial wetland ecosystems

et al. 2008

View full text Add to dashboard Cite

show abstract

“…Tolerant plant species tend to restrict soil-root and root-shoot transfers, and therefore have much less accumulation in biomass, whereas hyperaccumulators actively take up and translocate metals into above-ground tissues. Plants with high BAC (greater than 1) are suitable for phytoextraction; those Table 3 Differing areas of phytoremediation (from Salt et al 1998;Dietz and Schnoor 2001) Technology Description Phytoextraction Uptake of pollutants from environment and their concentration in harvestable plant biomass Phytostabilisation Reduction of mobility and bioavailability of pollutants in environment Phytovolatilisation Removal of pollutants from soil or water and their release into air, sometimes as a result of phytotransformation to more volatile and/or less polluting substances Phytotransformation Chemical modification of pollutants as a result of plant metabolism, both in planta and ex planta, often resulting in their inactivation, degradation (phytodegradation) or immobilisation (phytostabilisation)…”

Section: Metal Phytoextractionmentioning

confidence: 99%

Field crops for phytoremediation of metal-contaminated land. A review

2009

View full text Add to dashboard Cite

The use of higher plants to remediate contaminated land is known as phytoremediation, a term coined 15 years ago. Among green technologies addressed to metal pollution, phytoextraction has received increasing attention starting from the discovery of hyperaccumulator plants, which are able to concentrate high levels of specific metals in the above-ground harvestable biomass. The small shoot and root growth of these plants and the absence of their commercially available seeds have stimulated study on biomass species, including herbaceous field crops. We review here the results of a bibliographical survey from 1995 to 2009 in CAB abstracts on phytoremediation and heavy metals for crop species, citations of which have greatly increased, especially after 2001. Apart from the most frequently cited Brassica juncea ( L.) Czern., which is often referred to as an hyperaccumulator of various metals, studies mainly focus on Helianthus annuus L., Zea mays L. and Brassica napus L., the last also having the greatest annual increase in number of citations. Field crops may compensate their low metal concentration by a greater biomass yield, but available data from in situ experiments are currently very few. The use of amendments or chelators is often tested in the field to improve metal recovery, allowing above-normal concentrations to be reached. Values for Zn exceeding 1,000 mg kg(-1) are found in Brassica spp., Phaseolus vulgaris L. and Zea mays, and Cu higher than 500 mg kg(-1) in Zea mays, Phaseolus vulgaris and Sorghum bicolor (L.) Moench. Lead greater than 1,000 mg kg(-1) is measured in Festuca spp. and various Fabaceae. Arsenic has values higher than 200 mg kg(-1) in sorghum and soybean, whereas Cd concentrations are generally lower than 50 mg kg(-1). Assisted phytoextraction is currently facilitated by the availability of low-toxic and highly degradable chelators, such as EDDS and nitrilotriacetate. Currently, several experimental attempts are being made to improve plant growth and metal uptake, and results are being achieved from the application of organic acids, auxins, humic acids and mycorrhization. The phytoremediation efficiency of field crops is rarely high, but their greater growth potential compared with hyperaccumulators should be considered positively, in that they can establish a dense green canopy in polluted soil, improving the landscape and reducing the mobility of pollutants through water, wind erosion and water percolation

show abstract

“…Interestingly, most of the cytochrome P450 genes expressed by pathogen-inoculation were also induced by heavy metal treatment. Several P450s can be induced by light, whereas others are induced by plant stresses such as wounding, pathogen or xenobiotic compounds (Dietz and Schnoor 2001). Cytochrome P450 dependent monooxygenases are a large group of heme-containing enzymes, most of which catalyze NADPH-and O 2 -dependent hydroxylation reactions.…”

Section: Discussionmentioning

confidence: 99%

Identification of lead-regulated genes by suppression subtractive hybridization in the heavy metal accumulator Sesbania drummondii

Srivastava

Venkatachalam

Raghothama

et al. 2006

Planta

View full text Add to dashboard Cite

Heavy metal contamination of soils is of widespread occurrence as a result of human, agricultural and industrial activities. Among heavy metals, lead is a potential pollutant that readily accumulates in soils and sediments. Although lead is not an essential element for plants, it gets easily absorbed and accumulated in Sesbania drummondii, which exhibits a significant level of tolerance to lead. The response of a metal tolerant plant to heavy metal stress involves a number of biochemical and physiological pathways. To investigate the overall molecular response of a metal-tolerant plant to lead exposure, suppression subtractive hybridization (SSH) was used to construct a cDNA library enriched in lead induced mRNA transcripts from lead-tolerant Sesbania. Screening the library by reverse Northern analysis revealed that between 20 and 25% of clones selected from the library were differentially regulated in lead treated plants. After differential screening, we isolated several differentially expressed cDNA clones, including a type 2 metallothionein (MT) gene which is involved in detoxification and homeostasis and shown to be differentially regulated in lead treated plants. The data from the reverse Northern analysis was further confirmed with conventional Northern analysis of a select group of genes including MT, ACC synthase/oxidase, cold-, water stress-, and other abiotic stress-induced genes, which are up-regulated rapidly in response to lead treatment. The mRNA levels of MT increased substantially after lead treatment indicating a potential role for it under lead stress in Sesbania. The present results show that SSH can serve as an effective tool for isolating genes induced in response to lead heavy metal tolerance in Sesbania. A better understanding of lead induced gene expression in Sesbania should help select candidates associated with remediation of heavy metal toxicity. The possible link between this result and the heavy-metal response of plants is discussed.

show abstract

Advances in Phytoremediation

Cited by 100 publications

References 19 publications

Mitigation of agricultural nonpoint-source pesticide pollution in artificial wetland ecosystems

Mitigation of agricultural nonpoint-source pesticide pollution in artificial wetland ecosystems

Field crops for phytoremediation of metal-contaminated land. A review

Identification of lead-regulated genes by suppression subtractive hybridization in the heavy metal accumulator Sesbania drummondii

Contact Info

Product

Resources

About