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Geogenic organic carbon (GOC) from sedimentary rocks is an overlooked fraction in soils that has not yet been quantified but influences the composition, age, and stability of total organic carbon (OC) in soils. In this context, GOC is the OC in bedrock deposited during sedimentation. The contribution of GOC to total soil OC may vary, depending on the type of bedrock. However, no studies have been carried out to investigate the contribution of GOC derived from different terrestrial sedimentary rocks to soil OC contents.In order to fill this knowledge gap, 10m long sediment cores from three sites recovered from Pleistocene loess, Miocene sand, and Triassic Red Sandstone were analysed at 1m depth intervals, and the amount of GOC was calculated based on C-14 measurements. The C-14 ages of bulk sedimentary OC revealed that OC is comprised of both biogenic and geogenic components. The biogenic component relates to OC that entered the sediments from plant sources since soil development started. Assuming an average age for this biogenic component ranging from 1000-4000 years BP (before present), we calculated average amounts of GOC in the sediments starting at 1.5m depth, based on measured C-14 ages. The median amount of GOC in the sediments was then taken, and its proportion of soil mass (g GOC per kg(-1) fine soil) was calculated in the soil profile. All the sediments contained considerable amounts of GOC (median amounts of 0.10 g kg(-1) in Miocene sand, 0.27 g kg(-1) in Pleistocene loess, and 0.17 g kg(-1) in Red Sandstone) compared with subsoil OC contents (between 0.53 and 15.21 g kg(-1)). Long-term incubation experiments revealed that the GOC appeared comparatively stable against biodegradation. Its possible contribution to subsoil OC stocks (0.3-1.5m depth) ranged from 1% to 26% in soil developed in the Miocene sand, from 16% to 21% in the loess soil, and from 6% to 36% at the Red Sandstone site. Thus, GOC with no detectable C-14 content influenced the C-14

Geogenic organic carbon (GOC) from sedimentary rocks is an overlooked fraction in soils that has not yet been quantified but influences the composition, age, and stability of total organic carbon (OC) in soils. In this context, GOC is the OC in bedrock deposited during sedimentation. The contribution of GOC to total soil OC may vary, depending on the type of bedrock. However, no studies have been carried out to investigate the contribution of GOC derived from different terrestrial sedimentary rocks to soil OC contents.In order to fill this knowledge gap, 10m long sediment cores from three sites recovered from Pleistocene loess, Miocene sand, and Triassic Red Sandstone were analysed at 1m depth intervals, and the amount of GOC was calculated based on C-14 measurements. The C-14 ages of bulk sedimentary OC revealed that OC is comprised of both biogenic and geogenic components. The biogenic component relates to OC that entered the sediments from plant sources since soil development started. Assuming an average age for this biogenic component ranging from 1000-4000 years BP (before present), we calculated average amounts of GOC in the sediments starting at 1.5m depth, based on measured C-14 ages. The median amount of GOC in the sediments was then taken, and its proportion of soil mass (g GOC per kg(-1) fine soil) was calculated in the soil profile. All the sediments contained considerable amounts of GOC (median amounts of 0.10 g kg(-1) in Miocene sand, 0.27 g kg(-1) in Pleistocene loess, and 0.17 g kg(-1) in Red Sandstone) compared with subsoil OC contents (between 0.53 and 15.21 g kg(-1)). Long-term incubation experiments revealed that the GOC appeared comparatively stable against biodegradation. Its possible contribution to subsoil OC stocks (0.3-1.5m depth) ranged from 1% to 26% in soil developed in the Miocene sand, from 16% to 21% in the loess soil, and from 6% to 36% at the Red Sandstone site. Thus, GOC with no detectable C-14 content influenced the C-14

Soil development is a crucial aspect in the process of mine spoil restoration and is also critical for the establishment of the vegetation. In this short paper, we present the features of mine proto-soils (i.e. soils at the early stage of development) and the natural vegetation species colonizing mine sites in a dry arid environment of Kazakhstan characterized by surface disturbance due to mine activity to access phosphorite deposit.These disturbed soils showed morphological features very different from each other (particularly horizons depth and sequence), even if the main chemical features were quite homogeneous. This is reasonably linked to the features of the Human Transported Material derived from mine operation that was scattered around the mine area. The most abundant natural plants found in the study area belong to the Poacee, Asteraceae and Fabacee families (with 4 species each). Biomass contribution for all species is very low; the root biomass was greater than above ground biomass, contributing to a modest soil development.

Wild specimens of Helichrysum italicum, with their soil clod, were gathered from sites with different contamination levels by heavy metals (Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, Zn) in the abandoned Niccioleta mine (Tuscany, Italy). We examined the effects of heavy metals (HM) on the morphology of H. italicum growing on mine soils, with the following objectives: to determine the fate of HM within the soilplant system; to highlight morphological modifications at anatomical and cytological level; to ascertain the plant tolerance to heavy metals, and their resilience capacity. Plants appeared macroscopically not affected by toxic signals. Light microscopy and TEM observations of leaves show a clear difference in the cell organization of not-contaminated and contaminated samples. Trichomes of the polluted plants present a completely different morphology in comparison to nonpolluted ones, with a stalk of 3-4 cells and a large secreting apical cell, a palisade parenchyma less organized, and a reduction of leaf thickness. A gradual restoration of cell organization suggests that somewhat resilience occurred in plants. The resilience capacity points to H. italicum as an useful species in remediation projects.

[Purpose] The presence of high concentrations of trace elements (TEs) in mine soils like those in the Sierra Minera of La Unión-Cartagena (SE Spain) limits the development of a vegetation cover on such sites, and pollution dispersion by water and wind erosion represents a serious risk for the surrounding ecosystems. The aim of this study was to evaluate different phytostabilisation procedures based on the co-culture of a legume (Bituminaria bituminosa) and a high-biomass (Piptatherum miliaceum) species for this type of soils., [Materials and methods] A pot experiment was carried out where B. bituminosa was tested as a soil pre-treatment strategy. Five different procedures were followed to study the growth stimulation or competition of both species in a contaminated soil from the Sierra Minera: (i) sowing of P. miliaceum without B. bituminosa (control treatment), (ii) sowing of P. miliaceum for co-cultivation of both species, (iii) sowing of P. miliaceum and co-cultivation of both species in soil with compost, (iv) harvesting and elimination of the aerial part of the plants before sowing of P. miliaceum and (v) harvesting and incorporation to the soil of the aerial part of B. bituminosa before sowing of P. miliaceum., [Results and discussion] The results showed that the co-culture of both species favoured the growth of P. miliaceum, whilst incorporating the aerial part of the legume to the soil increased nitrogen concentration in P. miliaceum but reduced its growth. The use of compost improved both the growth and N uptake of P. miliaceum and did not inhibit nodulation in B. bituminosa. TE extractability in the soils and accumulation in the plants were rather low and very little affected by the addition of the amendments or by co-culture of species., [Conclusions] Nitrogen availability plays an important role in P. miliaceum growth in TE-contaminated mine soils. The addition of compost together with legume cultivation is proposed as an effective combination for the cultivation of P. miliaceum in these soils, as both plant growth and soil conditions were improved following this procedure.

Received 29 November 2009 / Received in revised form 24 October 2010 / Accepted 6 November 2010 / Available online 3 December 2010. © 2010 Elsevier B.V. All rights reserved., The aims of this study were to assess arsenic concentrations and solubility in soils, and its uptake by plant species growing in an area strongly affected by mining activities in Murcia (SE, Spain) paying attention to the mineralogical composition of the soils and the relation of the same with the bioavailability of this element. For this, extractionswere madewith several chemical reagents, to determine the bioavailability of the element in different environmental conditions (natural or potential) and, especially, the arsenic bioavailable for the plant uptake. Maximum extraction was achieved using the Mehra and Jackson procedure, while the least effective extractant was an ammonium sulphate solution. The strongest relationship between the As determined by soil chemical extractions and the As measured in plant biomass was found using the oxidisable-organic matter extraction procedure., Ministerio de Ciencia e Innovación (España), Depto. de Mineralogía y Petrología, Fac. de Ciencias Geológicas, TRUE, pub

Carbon accreditation of forest development projects is essential for sequestering atmospheric CO2 under the provisions of the Kyoto Protocol. The carbon sequestration potential of surface coal-mined lands is not well known. The purpose of this work was to determine how to measure carbon sequestration and estimate the additional amount that could be sequestered using different reforestation methods compared to the common practice of establishing grasslands. I developed a thermal oxidation technique for differentiating sequestered soil carbon from inorganic and fossilized carbon found at high levels in mine soils along with a geospatial and statistical protocol for carbon monitoring and accounting. I used existing tree, litter, and soil carbon data for 14 mined and 8 adjacent, non-mined forests in the Midwestern and Eastern coal regions to determine, and model sequestered carbon across the spectrum of site index and stand age in pine, mixed, and hardwood forest stands. Finally, I developed the framework of a decision support system consisting of the first iteration of a dynamic model to predict carbon sequestration for a 60-year period for three forest types (white pine, hybrid poplar, and native hardwoods) at three levels of management intensity: low (weed control), medium (weed control and tillage) and high (weed control, tillage, and fertilization). On average, the highest amount of ecosystem carbon on mined land was sequestered by pine stands (148 Mg ha-1), followed by hardwood (130 Mg ha-1) and mixed stands (118 Mg ha-1). Non-mined hardwood stands contained 210 Mg C ha-1, which was about 62% higher than the average of all mined stands. After 60 years, the net carbon in ecosystem components, wood products, and landfills ranged from 20 to 235 Mg ha-1 among all scenarios. The highest net amount of carbon was estimated under mixed hardwood vegetation established by the highest intensity treatment. Under this scenario, a surface-mined land of average site quality woul

[Truncated abstract] Many soil properties are involved in supporting the growth of plants and in limiting soil degradation. The present study was carried out to provide a basis for minimising environmental impact by providing a firm understanding of the soil properties that affect plant growth for soils developed from mining waste from the Wesfarmers Premier coalmine at Collie. The purpose of this study was to provide an understanding of the soil materials and to identify the potential interactions between soil properties and plants for soils developed on coalmine materials at the Premier mine, Collie. This research was to identify the nature of the manmade soils so as to determine if soil forming processes are active, to determine soil acidity including pH buffering capacity and the lime requirement of soils, to measure water retention characteristics and soil available water for plant growth, to relate soil properties to possible effects on plant growth, and to identify management strategies to improve soil conditions and overcome plant growth constraints. Seventy-seven manmade horizons from pits in 18 constructed soils, ranging from 9 to 21-years old, were analyzed throughout this study. These samples are classified based on soil depth, layer (topsoil and subsoil), and age of soil since rehabilitation. The methods for doing most of the analyses follow the Australian Soil and Land Survey handbook by Rayment and Higginson (1992). The results are presented quantitatively and soil properties are compared to provide information on pedogenic processes, the extent of soil development, the ability of the soils to resist degradation and to provide an indication of soil parent materials, Thesis (M.Sc.(Agric.))--University of Western Australia, 2004

In the post-mining landscapes of Lusatia, forest soils develop from extremely aeid, lignite-rich open cast mine spoils. The sites have been ameliorated with 8sb from lignite-fired power stations prior to afforestation. During stand development, incorporation of plant-derived organic matter leads to an intimate mixture with the substrate-derived lignite in the first centimetres of the soil CAí horizon). The objective of the study was to characterise and to compare the composition of organic matter of mine soils under forest which contain substantial amounts of lignite. Therefore, the forest floor and the mineral soil (Ai and Cv horizon) under a 20-year-old pine and a 36-year-old red oak site were analysed for elemental composition, magnetic susceptibility, chemical structure by cross-polarisation magic angle spinning (CPMAS) I3C and ISN nuclear magnetic resonance (NMR) spectroscopy and lignite content by radiocarbon dating. The 13e CPMAS NMR spectra of!he forest fioor and Ai horizon reveal signals at 56, 72, 105, 119, 130 and 150 ppm, indicating the presence of carbohydrates and lignin ariginating from plant material. Additionally, structures characteristic for lignite material (aromatic and aliphatic carbon) could be observed in the Oh and Ai horizons. Using radiocarbon dating, 25 to 83% of the total carbon in these horizons can be assigned to lignite. Lignite carban may also indicate carbonaceous particles derived from amelioration ash as well as from lignite-derived airborne contamination, which are possible carbon sources of the forest floor and the surface soil. 13C NMR and radiocarbon dating show that the subsoil Cv horizon. is dominated by carbon derived from lignite. From these results it is concluded that mine soils, rich in lignite contain up to four organic matter types, namely lignite inherent to the parent substrate, organic matter derived from decomposition of plant residues, carbonaceous particles in amelioration ash and carbonaceous particles from air

[Resumen] Se estudian las principales limitaciones para la recuperación de los suelos de explotaciones mineras de la provincia de La Coruña. A pesar de que hay una gran heterogeneidad, especialmente en aspectos como textura, pedregosidad y/o rocosidad, puede se ñalarse que las mayores dificultades para la revegetación derivan de la pobreza en materia orgánica y de la baja fertilidad actual y potencial, manifestada en la escasez de P, N y de reservas minerales. Los procesos· de toxicidad relativamente escasos, están relacionados con ambientes extremadamente ácidos en los que pueden encontrarse altos niveles de Al en el complejo de cambio y metales pesados en formas solubles. La pedregosidad es un limitante importante en algunas escombreras de dunitas, anfibolitas y esquistos ricos en cuarzo. Parece aconsejable la implantación de especies pioneras, frugales y tolerantes y, si es posible, con intervención de leguminosas. El aporte de residuos o subproductos ricos en materia orgánica tales como: lodos de depuradoras o industrias de la alimentación, compost de residuos sólidos urbanos, subproductos de industrias de la madera... o de materiales que deben ser removidos (lodos fluviales o de estuario, desmontes... ) son favorables siempre y cuando tengan una composición complementaria con la de los escombros o materiales de mina a recuperar., [Abstract] Mine soils at La Coruña (NW Spain) are studied in order to know their main limitations for reclamation. In spite of their heterogeneity (texture, stoniness) the main limitations for revegetation are: low levels of organic matter and low fenility, current (small amounts ofP and N) and potential (small) pool of weatherable (minerals). The relatively rare toxicity processes are related to very acidic environments, where high levels of exchangeable aluminium and heavy metals can occur. Stoniness is limitant in sorne dunites, amphibolites and quartz-schist spoils. It seems to be advisable a revegetation with pioneers, frugal and tolerant species, and, if possible, including leguminous. Treatments with organic amendments: municipal sewage sludge, compost, paper mill wastes, sawdust, or materials manipulated by man (river and estuary sludges, moved earthy materials) is favourable if their composition is complementary with the mine spoil.