Efeito da adição de fontes de matéria orgânica como amenizantes do efeito tóxico de B, Zn, Cu, Mn e Pb no cultivo de Brassica juncea

Abstract

RESUMOAtividades humanas como mineração, siderurgia e aplicação de fertilizantes tornam a poluição por metais sério problema ambiental na atualidade. A fitorremediação -uso de plantas e da microbiota, associada ou não a adições de amenizantes de solo, para extrair, seqüestrar e, ou, reduzir a toxicidade dos poluentes -tem sido descrita como uma tecnologia efetiva, não-destrutiva, econômica e socialmente aceita para remediar solos poluídos. O objetivo deste trabalho foi avaliar a eficiência da mostarda na remoção de Zn, Cu, Mn, Pb e B de um solo contaminado e o efeito da adição de materiais orgânicos na redução da disponibilidade de metais pesados e B para essa planta. O trabalho foi realizado em casa de vegetação, com delineamento inteiramente casualizado em esquema fatorial 3 x 5 com quatro repetições, utilizando 0, 7, 14, 21 e 28 g kg -1 de C no solo. Os materiais orgânicos utilizados foram: solomax, turfa e concentrado húmico mineral (CHM). A adição de turfa e concentrado húmico mineral reduziu os teores de Zn, Cu, Pb e B extraíveis do solo e na parte aérea da mostarda; contudo, essa redução não foi suficiente para impedir os efeitos fitotóxicos dos elementos. A adição dos materiais orgânicos promoveu aumento nos teores de Mn no solo, entretanto apenas o solomax proporcionou aumento na concentração do elemento na parte aérea das plantas. Os efeitos da turfa e do CHM sobre a disponibilidade de Zn, Cu, Mn, Pb e B no solo, a concentração na parte aérea e o crescimento das plantas indicaram o potencial desses materiais como agentes amenizantes de toxicidade e do solomax como auxiliar em programas de fitoextração induzida.Termos de indexação: fitoestabilização, fitoextração, Brassica juncea, poluição, turfa.( As a result of anthropogenic activities such as mining, metal industry and agricultural fertilizer application, metal pollution has become one of the most serious environmental problems of today. Phytoremediation denotes the use of plants and micro-biota, together or without soil amendments, to extract, sequester, and/or detoxify pollutants, has been reported to be an effective, non-destructive, inexpensive and socially accepted technique to remediate polluted soils. The objective of this work was to evaluate the efficiency of organic amendments in the reduction of heavy metal and B availability for mustard. The experiment was carried out under greenhouse conditions and the treatments arranged in a 3 x 5 factorial scheme. The following organic materials were used: solomax, peat, and humic mineral concentrate (0, 7, 14, 21, and 28 g kg -1 C). Peat and humic mineral concentrate reduced extractable Zn, Cu, Pb and B in soil and mustard shoots, though not enough to avoid toxic effects on plants. The organic amendments also raised the concentrations of extractable Mn in the soil, however only solomax produced an increase of Mn in shoots. The effects of peat and humic mineral concentrate on the availability of Zn, Cu, Mn, Pb and B in soil and shoots and on mustard growth indicated the potential as amendment for cont...

Senna multijuga and peat in phytostabilization of copper in contaminated soil

“…Therefore, it avoids greater risks to the plants due to the low activity of the contaminant in the plants (Marques et al, 2000). However, according to the results obtained for the accumulation of Cu(II), the species of S. multijuga presented low phytostabilization potential when compared to other studies with different plant species such as Brassica juncea and Cedrela fissilis (Santos & Rodella, 2007;Caires et al, 2011).…”

“…This result is unexpected because peat is considered a Cu(II) toxicity ameliorating agent (Santos & Rodella, 2007). Hence, it reduces the amount of the metal available for plant uptake, since this material contains a natural high amount of humic substances, which are responsible for the adsorption of metals (Franchi et al, 2003).…”

Nitrogen fertilization by deep bedding swine production and its effects on dry matter production and accumulation of nutrients by maize

“…According to SANTOS & RODELLA (2007), higher levels of Fe and Mn in corn under application of CSS, could be justified by the formation of soluble organic complexes, especially low molecular weight, organic matter. In most cases, the organic material to a lesser extent affects the availability of Fe and Mn in the Zn and especially to Cu.…”

Fertility Evaluation of Limed Brazilian Soil Polluted with Scrap Metal Residue

“…Mitigation can be used to reduce further undesirable impacts on chemical and physical soil degradation, to immobilize contaminants and to enable plant growth in contaminated areas to protect the soil from erosion [12][13][14]. Liming and the addition of organic materials are considered the most promising mitigation techniques for reducing the availability of heavy metals in soil [15][16][17].…”