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The general-purpose genotype hypothesis and the hypothesis of the evolution of invasiveness predict that invasive species are characterized by particular traits that confer invasiveness. However, these traits are still not well-defined. In this study, ecophysiological traits of eight populations of the invasive shrub Buddleja davidii from a wide range of European locations and five co-occurring native woody species in Germany were compared in a common garden experiment. We hypothesized that the invader has higher resource capture ability and utilization efficiency than the natives. No differences were detected among the eight populations of B. davidii in any of the traits evaluated, indicating that the invader did not evolve during range expansion, thus providing support to the general-purpose genotype hypothesis. The invader showed significantly higher maximum electron transport rate, maximum carboxylation rate, carboxylation efficiency, light-saturated photosynthetic rate (P max) and photosynthetic nitrogen utilization efficiency (PNUE) than the five natives. Leaf nitrogen content was not significantly different between the invader and the natives, but the invader allocated more nitrogen to the photosynthetic machinery than the natives. The increased nitrogen content in the photosynthetic machinery resulted in a higher resource capture ability and utilization efficiency in the invader. At the same intercellular CO2 concentration, P max was significantly higher in the invader than in the natives, again confirming the importance of the higher nitrogen allocation to photosynthesis. The invader reduced metabolic cost by increasing the ratio of P max to dark respiration rate (R d), but it did not reduce carbon cost by increasing the specific leaf area and decreasing leaf construction cost. The higher nitrogen allocation to the photosynthetic machinery, P max, PNUE and P max/R d may facilitate B. davidii invasion, although studies involving a wide range of invasive spec

The co-leaching solution contained 2.68 g/l V, 37.21 g/l Mn, 11.46 g/l Al, 5.72 g/l Fe3+, 0.84 g/l Fe2+, 4.31 g/l Mg, 2.54 g/l K, 1.57 g/l Na, 0.13 g/l Si and 0.088 g/l Ca. Na and K were removed from the solution by sodium jarosite precipitation at pH 1.8-2 in the presence of dilute H2SO4 at 95 degrees C with aeration for 3 h, Fe and Al were removed by increasing the pH to 5.5-6 and the addition of lime with a reaction time of 80 degrees C for 1 h, and Mg was removed by the addition of MnF2. The purified solution was subjected to solvent extraction using the trialkylamine N235 and secondary octyl alcohol and the results verified using countercurrent simulation experiments. V extraction of 99.21% was obtained with three countercurrent extraction stages using 5% v/v N235 and 5% v/v secondary octyl alcohol at an initial aqueous pH of 3.0 and organic/aqueous phase ratio of 1.0. V(V) could be completely stripped after a three-stage countercurrent process using 20 wt% NH4Cl at an organic/aqueous phase ratio of 1.0. A process flow sheet for the recovery of V(V), as well as Mn(II) is presented., The co-leaching solution contained 2.68 g/l V, 37.21 g/l Mn, 11.46 g/l Al, 5.72 g/l Fe3+, 0.84 g/l Fe2+, 4.31 g/l Mg, 2.54 g/l K, 1.57 g/l Na, 0.13 g/l Si and 0.088 g/l Ca. Na and K were removed from the solution by sodium jarosite precipitation at pH 1.8-2 in the presence of dilute H2SO4 at 95 degrees C with aeration for 3 h, Fe and Al were removed by increasing the pH to 5.5-6 and the addition of lime with a reaction time of 80 degrees C for 1 h, and Mg was removed by the addition of MnF2. The purified solution was subjected to solvent extraction using the trialkylamine N235 and secondary octyl alcohol and the results verified using countercurrent simulation experiments. V extraction of 99.21% was obtained with three countercurrent extraction stages using 5% v/v N235 and 5% v/v secondary octyl alcohol at an initial aqueous pH of 3.0 and organic/aqueous phase ratio of 1.0. V(V) could be completely stripped after a three-stage countercurrent process using 20 wt% NH4Cl at an organic/aqueous phase ratio of 1.0. A process flow sheet for the recovery of V(V), as well as Mn(II) is presented.