https://ogma.newcastle.edu.au/vital/access/ /manager/Index en-au 5 Predicting plant uptake of cadmium: validated with long-term contaminated soils https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:29511 Cucumis sativa L. (cucumber). The parameter log Kf was predicted with soil pHca, logCEC and log OC. Transfer of soil pore-water Cd2+ to shoots was described with a power function (R2 = 0.73). The dataset was validated with 13 long-term contaminated soils (plus 2 control soils) ranging in Cd concentration from 0.2 to 300 mg kg−1. The series of equations predicting Cdshoot from pore-water Cd2+ were able to predict the measured data in the independent dataset (root mean square error = 2.2). The good relationship indicated that Cd uptake to cucumber shoots could be predicted with Cdpore and Cd2+ without other pore-water parameters such as pH or Ca2+. The approach may be adapted to a range of plant species.]]> Wed 23 Feb 2022 16:06:46 AEDT ]]> Copper interactions on arsenic bioavailability and phytotoxicity in soil https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:43123 Tue 13 Sep 2022 14:39:25 AEST ]]> Zinc-arsenic interactions in soil: solubility, toxicity and uptake https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:31400 Cucumis sativa L) conducting 4 weeks pot study in 5 different soils spiked with As (0, 2, 4, 8 to 1024 mg kg-1 ) individually and with Zn at two phytotoxic doses. The As pore-water concentration was significantly reduced (df = 289, Adjusted R2 = 0.84, p < 0.01) in the presence of Zn in the whole dataset, whereas Zn and Zn2+ activity in pore-water was reduced significantly only in the two alkaline soils. This outcome may be due to adsorption/surface precipitation or tertiary bridging complexation. No homogenous precipitation of zinc arsenate could be established using electron microscopy, XRD or even equilibrium calculations. For bioaccumulation phase, no significant effect of Zn on As uptake was observed except acidic MG soil whereas, Zn uptake was significantly reduced (p < 0.05) by As in whole dataset. However, an additive response was observed mostly except acidic MG soil. The synergistic response (more than additive) was predominant in this soil for a wide range of inhibition concentration (0¿80%) at both Zn EC10 and EC50 levels. Since additive response is mostly considered in risk assessment for mixtures, precautions should be implemented for assessment of toxicity for As-Zn mixture in acidic soil due to their synergistic response in some soils.]]> Sat 24 Mar 2018 08:43:26 AEDT ]]> Predicting plant uptake and toxicity of lead (Pb) in long-term contaminated soils from derived transfer functions https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:29927 Cucumis sativa L. (cucumber) focusing primarily on pore-water Pb data from 10 different soils after 12 weeks ageing. Phytotoxicity expressed in terms of Pb2+ was observed to occur in the nanomolar range in neutral to alkaline soils (EC50 values 90 to 853 nM) and micromolar levels for acidic soils (EC50 values 7.35 to 9.66 μM). Internal Pb concentrations relating to toxicity (PT50) in roots and shoots also decreased with increasing pore-water pH (R2 = 0.52 to 0.53). From a series of dose-response studies, we developed transfer functions predicting Pb uptake in C. sativa and we validated these functions with long-term Pb contaminated soils. The significant independent parameters were pore-water Pb2+ and dissolved Pb plus dissolved organic carbon (DOC). The observed RMSE for the Pb-DOC model and Pb2+ were 2.6 and 8.8, respectively. The Pb-DOC model tended to under-predict Pb, whilst Pb2+ tended to over-predict accumulation despite reasonable RMSE values. Further validation is needed in soils with higher pore-water Pb solubility.]]> Sat 24 Mar 2018 07:30:55 AEDT ]]> Predicting phytotoxicity of metal(loid)s and their mixtures in soil using pore-water based transfer functions https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:28969 Mon 19 Aug 2024 14:42:40 AEST ]]>