Senna multijuga and peat in phytostabilization of copper in contaminated soil

ABSTRACT Phytoremediation is a technique that uses plants, whether associated or not to ameliorating agents, for phytostabilization of contaminated soil. The aim of this study was to evaluate the use of Senna multijuga associated with peat in the phytostabilization of copper contaminated soil. The experiment was carried out in a greenhouse for 120 days, using an entirely randomized design in a factorial arrangement (2 x 6), with and without peat (200 mL L-1 soil) and six doses of copper (0, 60, 120, 180, 240, 300 mg kg-1), with six repetitions of each treatment. At 120 days after seedling, the plants were evaluated for height, stem diameter, root and aerial dry matter, contents and accumulated amount of copper in the root system and aerial part. Also, the Dickson quality indexes, as well as tolerance and translocation indexes were analyzed. The results showed that the use of 200 mL of peat L-1 of soil was inefficient as an ameliorating agent for copper-contaminated soil, but it acted as a soil conditioner, increasing the morphological parameters of S. multijuga. In its initial development period, the S. multijuga species presented low copper phytostabilization potential in contaminated soil

Acumulação e translocação de zinco em mudas de espécies do gênero Eucalyptus e Corymbia

RESUMOO acúmulo e a compartimentalização de zinco são distintos entre as espécies florestais. O objetivo do trabalho foi, portanto, avaliar a capacidade de acumulação e de translocação de zinco em mudas de Eucalyptus e Corymbia em solo contaminado com zinco. O experimento foi conduzido no período de outubro de 2011 a março de 2012, em casa de vegetação, em delineamento experimental inteiramente casualizado, com arranjo fatorial (4 x 8), com doze repetições. Foram utilizadas quatro espécies: Eucalyptus. grandis W. Hill ex Maid., Eucalyptus. salignaSmith, Eucalyptus. dunnii Maiden e Corymbia citriodora (Hook.) K.D. Hill & L.A.S. Johnson, e oito doses de zinco (0, 140, 280, 420, 560, 700, 840 e 980 mg kg-1 de solo). As mudas das espécies florestais mostraram comportamento diferenciado em relação às doses de zinco aplicadas no solo com redução na massa seca da parte aérea. O E. dunnii apresenta maior redução na altura de planta, volume radicular, área foliar e massa seca radicular em relação às demais espécies. O C. citriodora apresenta maior acumulação de zinco na parte aérea e índice de translocação e baixo coeficiente de impacto do teor relativo com as doses aplicadas no solo, indicando tolerância em solos contaminados

Copper translocation and tolerance in seedlings of tree species grown in contaminated soil

ABSTRACTHigh concentrations of copper (Cu) may be toxic to plants, yet some species can be tolerant to soils contaminated by this metal. The study aimed to evaluate Cu translocation and tolerance in seedlings of ‘timbaúva’ (Enterolobium contortisiliquum (Vell.) Morong), ‘pata-de-vaca’ (Bauhinia forficata Link) and ‘amendoim-bravo’ (Pterogyne nitensTul) subjected to Cu-contaminated soil. The study was conducted in a greenhouse for 120 days, using as substrate a clayey Oxisol. The experiment was set in a completely randomized design, using a 3 x 6 factorial scheme, corresponding to three forest species (‘timbaúva’, ‘pata-de-vaca’ and ‘amendoim-bravo’) and six Cu doses in the soil (0, 60, 120, 180, 240 and 300 mg kg-1), with six replicates. The following variables were analysed: total dry matter, Cu content and its accumulation in roots and shoots, tolerance and translocation indices and the coefficient of impact of the contamination on the relative contents of Cu in roots and shoots. ‘Timbaúva’ showed lower reduction in total dry matter with the increase of Cu doses in the soil, proving to be able to decrease Cu translocation to the shoots and tolerate doses of up to 236 mg kg-1 of this metal in the soil. ‘Timbaúva’ seedlings are more tolerant to contamination of Cu in soil, compared with seedlings of ‘amendoim-bravo’ and ‘pata-de-vaca’

Growth, tolerance and zinc accumulation in Senna multijuga and Erythrina crista-galli seedlings

ABSTRACT Zinc (Zn) is a micronutrient that is reaching toxic levels in the soil, with the intensification of agricultural and industrial activities. The objective of this study was to evaluate the growth, accumulation and tolerance of Erythrina crista-galli and Senna multijuga seedlings in soil with addition of increasing Zn levels. The study was conducted in a greenhouse for 120 days, using a completely randomized design in a 2 x 6 factorial arrangement, corresponding to two tree species (S. multijuga and E. crista-galli) and six doses of zinc in the soil (0, 200, 400, 600, 800 and 1000 mg kg-1) with six replicates. E. crista-galli and S. multijuga seedlings decreased root and shoot dry weight with increasing Zn doses. E. crista-galli and S. multijuga have low Zn translocation index and are capable to phytostabilize Zn in the roots. E. crista-galli had greater tolerance to Zn compared with S. multijuga. The species have potential for Zn phytostabilization programs in contaminated soil