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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, 10 m long sediment cores from three sites recovered from Pleistocene loess, Miocene sand, and Triassic Red Sandstone were analysed at 1 m depth intervals, and the amount of GOC was calculated based on 14C measurements. The 14C 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 1.5 m depth, based on measured 14C 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 (0.3–1.5 m 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 14C content influenced the 14C ages of subsoil OC and may partly explain the strong increase in 14C ages observed in many subsoils. This could be particularly important in young soils on terrestrial sediments with comparatively low amounts of OC, where GOC can make a large contribution to total OC stocks.

Organic wastes have a positive impact on soil physical and chemical properties in the agroecosystems. However, its main effects on soil organic carbon (SOC) or total organic carbon, TOC (SOC and coal-C) contents as well as their effects on soil physico-chemical properties are still unclear. Two types of organic wastes (maize straw and manure) were utilized in dryland affected by mining activities to quantify their relative effect on soil physico-chemical properties. Regression analysis was used to assess the relationship between the soil physical properties, SOC, and TOC as well as their respective contributions to improving these properties. Treatments included control (CK), straw (S), low manure (LM), medium manure plus straw (S-MM), and high manure plus straw (S-HM). The results showed that SOC, soil bulk density, mean weight diameter (MWD), soil total porosity, soil penetration resistance, saturated hydraulic conductivity, and soil infiltration rate were strongly influenced by the application of organic wastes. A stronger linear relationship between SOC and the MWD, (R2 = 0.93, p &lt, 0.05) compared to that between TOC and MWD indicated the important role of SOC in improving soil aggregation relative to the effect of TOC. According to the principal component analysis (PCA), the application of organic wastes had stronger effects on SOC contents and physical properties than TOC (SOC and coal-C). These findings advance our understanding of the actual effect of organic wastes on soil physical properties and SOC in dryland affected by mining activities and could inform fertilizer management decisions to improve soil properties.

Purpose Heavy metal accumulation produces significant physiological and biochemical responses in vascular plants. Plants growing on abandoned mine sites are of particular interest, since they are genetically tolerant to high metal concentrations. In this work, we examined the effect of heavy metals (HMs) on the morphology of T. officinale growing in pots with mine soils, with the following objectives: (1) to determine the evolution of HM concentration in leaves and roots over 3 years of cultivation; (2) to highlight possible damage at anatomical and cytological level.

Soil microbial communities are of crucial importance for the functioning of ecosystems developing in post-mining areas. The objective of this study was to compare the properties of microbial communities in mine soils reclaimed for forestry and in mine soils developing under vegetation from natural succession. Soil samples were taken from a degraded site prior to reclamation (MS), a site after 2 years of lupine cultivation (LUP), reclaimed post-mining sites afforested with Scots pine (R6, R20, R28), post-mining sites with spontaneously developing pine forest stands (S6, S20, S27) and two natural pine forest stands (F30, F100). The examined microbial properties included basal respiration (RESP), microbial biomass ( C mic ), C mic -to- C org ratio, potential nitrogen mineralization rate (Min_N) and community-level physiological profiles (CLPPs) studied using Biolog ® Ecoplates. The lowest C mic , RESP and Min_N values were determined in soil MS ( C mic = 26.5 mg kg −1 , RESP = 1.06 μg C-CO 2 g −1 24 h −1 , Min_N = 5.2 μg N kg −1 24 h −1 ). Among the reclaimed mine soils the most biologically active was R6 ( C mic = 89.2 mg kg −1 , RESP = 7.28 μg C-CO 2 g −1 24 h −1 , Min_N = 213.2 μg N kg −1 24 h −1 ). C mic , RESP and Min_N gradually increased with soil age in S6, S20 and S27. Cluster analysis of CLPPs revealed a distinct difference between the natural forest soils and the mine soils. Among the mine soils, the least physiologically diverse was MS. In the successional mine soils, the metabolic abilities developed gradually with soil age. The CLPPs of the youngest successional mine soils resembled more the profiles of soil MS than those of natural forest soils whereas for the youngest reclaimed mine soils the opposite was the case. The results indicate that reclamation measures not only boost the gross microbial properties but also promote rapid development of metabolic abilities characteristic of natural forest soil microbial communities.

Newly vegetated sites provide opportunities to enlighten organic matter (OM) transformation mechanisms in soils and sediments at very early stages of development which, in turn, is relevant to better understand general ecosystem functioning. Mine acid soils and sediments in the Lusatian open-cast lignite mining district (Germany) contains high concentrations of fossil carbon (lignite) in mixture with recent OM from the local vegetation, both contributing to the humified OM pool. In this study, analytical pyrolysis (Py–GC/MS) was used to monitor the different C sources (lignite or plant derived) in developing mine tailing soils and sediments and their degree of degradation in contrasting environments. Representative vegetation and organic carbon (OC) rich soil/sediment fraction (humus fraction) were sampled at two depths (0-5 and 5-10 cm) in three plots along a transect covering an upland forest soil, a partially submerged sediment at the land–water interface and a constantly submerged sediment. The analysis of plant (lipds, isoprenoids, methoxyphenols and carbohydrates) and possible lignite (alkyl-napththalenes, alkyl-benzenes and PAHs) biomarkers released after pyrolysis supports previous findings in the area using other proxies. It was possible to discern OM sources in soil/sediments humus fractions, both from the substrate (lignite) as well as from the prevailing vegetation of the area. Environmental conditions in the submerged sediment seems to be favouring OM protection and the accumulation of decomposing plant material, whereas more intense OM degradation processes seems to prevail in the land–water interface areas characterized by fluctuating water levels. In addition, a well resolved series of organic sulphur compounds (OSC) found in the submerged sediments of rehabilited acid lakes, indicate the possible occurrence of particular mechanisms of C preservation in this extreme anoxic S rich environment i.e. via sulphur “quenching” with plant derived lipids during early diagenesis.

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 would sequester net carbon stock at 235 Mg C ha-1, at a rate of 3.9 Mg C ha-1 yr-1, which was 100% greater than a grassland scenario. Reforestation is a logical choice for mined land reclamation if carbon sequestration is a management objective. Ph. D.

Es recopilen dades referents a treballs de restauració d'activitats extractives a cel obert, i es discuteix la utilització de diferents tipus d'indicadors per tal d'avaluar la qualitat dels treballs de restauració, així com el patró amb el qual comparar aquests indicadors. Es proposen valors límit per a gruix del sòl, pedregositat, fraccions texturals, contingut de carbonats i matèria orgànica. Es discuteix l'avaluació dels treballs de restauració de les mines de carbó del Pedraforca com a exemple de l'ús de diferents tipus d'indicadors. D'entre els indicadors utilitzats més freqüentment, les mesures referents a la pèrdua de sòl per erosió (volum de sòl perdut i àrea afectada), les propietats físiques (densitat aparent, capacitat d'infiltració) i algunes característiques biològiques (flux de CO2) son les que han resultat de més utilitat. Això és així gràcies al caràcter integrador d'aquests atributs del sòl a les zones restaurades i a la relativa facilitat de mesura. En canvi, la informació referent a la vegetació arbustiva i arbòria, malgrat l'ús habitual que se'n fa, té una utilitat més limitada com a indicadora de la qualitat final dels treballs, atès el relativament curt termini transcorregut fins l'acabament del període legal de garantia de les obres de restauració (màxim cinc anys). Es presenta un exemple de taula global de puntuació de la qualitat de la restauració d'activitats extractives. Data on quarry reclamation are compiled and several reclamation-quality indicators are discussed. The use of soil quality standards is also discussed. Limit values for soil depth, stoniness, textural fractions, carbonate and organic matter content are proposed. The evaluation of Pedraforca's open cast coalmines reclamation is used as example for discussing quality indicators use. Among the current indicators of restoration quality, soil losses by erosion (volume of soil lost and affected area), physical properties (bulk density, infiltration rate) and some biological characteristics (CO2 efflux) are some of the more useful. This is due to the integrating character of those attributes easy to be measured. However, information about shrubs and trees, in spite of their current use, are more limited as indicator of final quality taking into account the short time of warranty (five years maximum) of restoration works. A global score table for restoration quality of mining activities is also shown.

20 pages, 4 figures, 6 tables, 49 references., 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 airborne lignite-derived contamination. 15N NMR spectroscopy revealed that most of the nitrogen of these soils is of recent biogenic origin.

[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.

This study assessed the development of microbial biomass, basal respiration, and the activities of dehydrogenase, urease, and acid phosphomonoesterase in sandy mine soils reclaimed for forestry and those developing under vegetation from natural succession. The mine soils contained significantly less organic C (Corg) and total N (Nt) than the natural forest soils. However, in some of them the microbial biomass and basal respiration attained values typical for the natural forest soils. The content of Nt proved to be the most important control on the microbial biomass, basal respiration, and the activities of dehydrogenase and phosphomonoesterase in the mine soils. All the microbial properties were positively related also to Corg content. The activities of dehydrogenase and urease depended strongly on microbial biomass (Cmic). Hence, high activities of these enzymes were determined in soils containing high Cmic. The acid phosphomonoesterase activity was also positively related to Cmic, but its activity was increased in the soils with low P contents.

The objective of this study was to compare chemical and microbial properties of sandy mine soils under young Scots pine, silver birch, and mixed pine-birch forest stands. The measured properties included the contents of organic C (C_{org}) and total N (Nt), the C_{org}-to-N_{t} ratio, pH, microbial biomass, basal respiration, and activities of dehydrogenase, acid phosphomonoesterase, and urease. Community level physiological profiles (CLPPs) of soil bacteria were determined with Biolog® test and genetic profiles with the DGGE method. Scots pine and silver birch did not affect the C_{org} and N_{t} contents in the studied mine soils. The soil under birch contained larger and more active microbial biomass than the soil under pine. Under the mixed stand, most of the microbial properties were intermediate between the pine and the birch stand. The DGGE profiling indicated different composition of soil bacteria under the birch stand compared to the other stands. Differences in CLPPs were less pronounced, probably due to functional redundancy of soil bacteria.

Foi estudada a utilização de Lolium perenne L. e de diferentes resíduos orgânicos (RO) na fitoestabilização controlada de solos degradados por atividades mineiras (Mina de Aljustrel, Faixa Piritosa Ibérica). Apesar da aplicação dos RO ter permitido a imobilização de Cu, Pb e Zn no solo, baixando a fracção efetivamente disponível, os teores foliares destes elementos não diminuíram significativamente. Os factores de acumulação (FA) obtidos, FA(Cu) e FA(Pb) <, Revista de Ciências Agrárias, vol. 34 n.º 2 (2011)