Phytoremediation: Metal decontamination of soils after the sequential forestation of former opencast coal land.

Phytoremediation through forestry may be an effective means for reducing the metal loading in lands reclaimed after surface-coal-mining in the UK. Planted with mixed woodland, the soil loading of 5 key metals (Zn, Cd, Mn, Pb and Cu) decreased, significantly and progressively, compared to soils left as grassland through a 14 year forestation chronosequence on land reclaimed from the former Varteg opencast coalmine, South Wales. Fourteen years after initial tree planting, soil metal loadings decreased by 52% for Cd (4.3 mg∙kg-1 per year), 48% for Cu (2.1 mg∙kg-1 per year), 47% for Zn (7.3 mg∙kg-1 per year), 44% for Pb. (7.1 mg∙kg-1 per year) and 35% for Mn (45 mg.kg-1 per year). Analysis of metal loadings in the leaves of Alnus glutinosa (L. Gaertn) (Common Alder) and Betula pendula (Roth) (Silver Birch) found both to be involved in metal uptake with birch taking up more Cd, Cu, Zn and Mn and Alder more Pb. Concentrations of Zn, Mn and Cd (Birch only) increased significantly in leaves from, but not in soils, under older plantings. Since different tree species take up metals at different rates, mixed plantings may be more effective in forest phytoremediation.

Toward a consistent modeling framework to assess multi-sectoral climate impacts.

Efforts to estimate the physical and economic impacts of future climate change face substantial challenges. To enrich the currently popular approaches to impact analysis-which involve evaluation of a damage function or multi-model comparisons based on a limited number of standardized scenarios-we propose integrating a geospatially resolved physical representation of impacts into a coupled human-Earth system modeling framework. Large internationally coordinated exercises cannot easily respond to new policy targets and the implementation of standard scenarios across models, institutions and research communities can yield inconsistent estimates. Here, we argue for a shift toward the use of a self-consistent integrated modeling framework to assess climate impacts, and discuss ways the integrated assessment modeling community can move in this direction. We then demonstrate the capabilities of such a modeling framework by conducting a multi-sectoral assessment of climate impacts under a range of consistent and integrated economic and climate scenarios that are responsive to new policies and business expectations.

Mobility of heavy metals associated with the natural weathering of coal mine spoils.

Knowledge of chemical mobility of heavy metals is fundamental to understanding their toxicity, bioavailability, and geochemical behavior. In this paper, two different methods, i.e. mineralogical means and sequential extractions, were employed to analyze the total contents, existing states, and chemical forms of heavy metals in coal mine spoils. The results demonstrate that the mobility of heavy metals in coal mine spoils depends not only on their existing states and the stability of their host minerals but also on the properties of the coal mine spoils. In the process of coal mine spoils-water interaction, sulfides that contain heavy metals first break down and release metals, which are then adsorbed and complexed by the iron oxyhydroxide colloid resulting from pyrite oxidization and organic matter. During the natural weathering of coal mine spoils, only a small fraction of these metals are released to the environment, and most of them still remains in the residual material.

Environmental influences on landslide activity : Almora Bypass, Kumaun Lesser Himalaya

Landslides are self-organizing and self-referenced systems. The conditions which lead to their emergence along Himalayan highways are not the same as those which their subsequent evolution. Landslides originate at sites which differ from average conditions by having significantly higher, steeper roadcuts, carved into steeper hillsides, with more finely bedded but less steeply dipping rocks, and fewer trees upslope. The system exhibits independence (autopoiesis) from its environment. Additionally, landslides dominated by rock-mechanical processes tend to produce lower angle outfalls from higher, north-facting, roadcuts than those dominated by soil-mechanical processes which are associated with greater dephts of below-soil regolith. However, the outfall volumes produced by the landdslides of different type are similar. These findings are generated from statistical (correlation/T-test/stepwise discriminant) analyses of data produced by a field survery of average environmental conditions, and the morphometry and environmental contexts of 88 landslides, on 7.6 km of the Almora Bypass (AU)