Effect of mowing versus abandonment of mesic grasslands in Central Europe on biomass use for biogas production: Implications for semi-natural ecosystem conservation.

The economic management of lignocellulosic biomass from semi-natural grasslands is now a challenge across Europe. The abandonment of mowing these grasslands leads to the gradual degradation of these ecosystems. This study investigates how chemical and biological factors affect the suitability of biomass from abandoned grasslands for biogas production.

Effect of peat organic matter on sulfide weathering and thallium reactivity: Implications for organic environments.

Weathering of Tl-containing sulfides in a model (12-week) peat pot trial was studied to better understand their geochemical stability, dissolution kinetics, alteration products and the associated release and mobility of anthropogenic Tl in organic environments. We also present the effect of industrial acid rainwater on sulfide degradation and Tl migration in naturally acidic peat. Sphalerite (ZnS) was much less stable in peat than other Tl-containing sulfides (galena and pyrite), and thus acted as a major phase responsible for Tl mobilization.

The Admont Grassland Experiment: 70 years of fertilizer application and its effects on soil and vegetation properties in an alluvial meadow managed under a three-cut regime.

Fertilizer application is a widely used management technique for increasing forage production from agricultural grassland. Fertilization is also a key driver of changes in soil nutrient status and plant species composition of grassland as shown in many short-term studies. Results from long-term experiments can further improve understanding of plant-soil relationships and help with management recommendations for agricultural and environmental outcomes.

Evaluation of thallium isotopic fractionation during the metallurgical processing of sulfides: An update.

In this study, we report combined Tl isotopic and Tl mineralogical and speciation data from a set of Tl-rich sulfide concentrates and technological wastes from hydrometallurgical Zn extraction. We also present the first evaluation of Tl isotopic ratios over a cycle of sulfide processing, from the ore flotation to pyro- and hydrometallurgical stages. The results demonstrate that the prevailing Tl form in all samples is Tl(I), without any preferential incorporation into sulfides or Tl-containing secondary phases, indicating an absence of Tl redox reactions.

Restoration management of cattle resting place in mountain grassland.

This study investigated the effect of restoration management of a weed-infested area, previously used as cattle resting place, on herbage production and nutrient concentrations in the soil and herbage. The experiment was undertaken from 2004 to 2011 at the National Park of Nízké Tatry, Slovakia. Three treatments were applied: (i) cutting twice per year, (ii) herbicide application, followed after three weeks by reseeding with a mixture of vascular plant species and then cut twice per year, and (iii) unmanaged.

The effects of first defoliation and previous management intensity on forage quality of a semi-natural species-rich grassland.

Semi-natural grasslands occupy large parts of the European landscape but little information exists about seasonal variations in their nutritive value during the growing season. This paper presents results of novel data showing the effect of 13 years of previous contrasting management intensities on herbage nutritional value in relation to different dates of first defoliation (by grazing or haymaking). The treatments were: extensive management and intensive management from previous years (1998-2011).

What is the effect of 19 years of restoration managements on soil and vegetation on formerly improved upland grassland?

Finding the best management strategies to restore grassland diversity and achieve a compromise between agricultural use and biodiversity protection is a global challenge. This paper reports novel data relating to the impacts of 19 years of restoration managements predicted to increase botanical diversity within reseeded upland temperate grassland common in less favoured areas in Europe. The treatments imposed were: continuous sheep grazing, with and without lime application; hay cutting only, with and without lime application; hay cutting followed by aftermath grazing, with and without lime application; and a control treatment continuing the previous site management (liming, NPK application and continuous sheep grazing).

Thallium stable isotope fractionation in white mustard: Implications for metal transfers and incorporation in plants.

We studied thallium (Tl) isotope fractionation in white mustard grown hydroponically at different Tl doses. Thallium isotope signatures in plants indicated preferential incorporation of the light Tl isotope during Tl uptake from the nutrient solution. Negative isotope fractionation was even more pronounced in dependence on how much the available Tl pool decreased.

Thallium contamination of desert soil in Namibia: Chemical, mineralogical and isotopic insights.

We studied arid desert soils from Namibia (Rosh Pinah) that were contaminated with up to 7 mg kg of thallium (Tl) via dust emitted from a local flotation tailing dam. Chemical extractions of waste and soil materials indicated that most of the Tl is strongly bound, in accordance with X-ray diffraction and X-ray absorption spectroscopy data that point to the predominant association of Tl with metal sulfides and phyllosilicates. The isotope fractionation factor εTl of the soil samples (from -0.

Thallium isotopes in metallurgical wastes/contaminated soils: A novel tool to trace metal source and behavior.

Thallium (Tl) concentration and isotope data have been recorded for contaminated soils and a set of industrial wastes that were produced within different stages of Zn ore mining and metallurgical processing of Zn-rich materials. Despite large differences in Tl levels of the waste materials (1-500mgkg), generally small changes in εTl values have been observed. However, isotopically lighter Tl was recorded in fly ash (εTl∼-4.

Isotopic Tracing of Thallium Contamination in Soils Affected by Emissions from Coal-Fired Power Plants.

Here, for the first time, we report the thallium (Tl) isotope record in moderately contaminated soils with contrasting land management (forest and meadow soils), which have been affected by emissions from coal-fired power plants. Our findings clearly demonstrate that Tl of anthropogenic (high-temperature) origin with light isotope composition was deposited onto the studied soils, where heavier Tl (ε(205)Tl ∼ -1) naturally occurs. The results show a positive linear relationship (R(2) = 0.

Thallium contamination of soils/vegetation as affected by sphalerite weathering: a model rhizospheric experiment.

The environmental stability of Tl-rich sphalerite in two contrasting soils was studied. Rhizospheric conditions were simulated to assess the risk associated with sulfide microparticles entering agricultural (top)soils. The data presented here clearly demonstrate a significant effect of 500 μM citric acid, a model rhizospheric solution, on ZnS alteration followed by enhanced Tl and Zn release.

Comparison of Al speciation and other soil characteristics between meadow, young forest and old forest stands.

The aim of this paper is to describe the influence of spruce (Picea abies) afforestation on soil chemical properties, especially on soil acidity and aluminium (Al) mobilization and speciation in soil. For our study we used a unique set of three adjacent plots, including a meadow and two spruce forest stands of different age, in otherwise comparable conditions. The plots were located in the region of Giant Mountains, north-eastern Czech Republic.

Assessment of soil aluminium pools along three mountainous elevation gradients.

Anthropogenic soil acidification in mountain forests and consequent Al release still present a significant problem in many regions. The effect of deposition may differ according to stand conditions, including altitude. This contribution is focused on three elevation transects, two in the Jizera Mountains strongly influenced by acid deposition, one in the less affected Novohradske Mountains.

Grass cover on forest clear-cut areas ameliorates some soil chemical properties.

Clear-cut areas formed after forest decline due to acid deposition, pest attacks, or wind-breaks in temperate mountainous regions are often populated by grass (mainly Calamagrostis villosa). This study focused on the changes of soil chemical characteristics under the grass cover replacing the forest, focusing mainly on aluminium (Al) speciation. Clear-cut area due to strong acid deposition in the Jizera Mountains (Northern Bohemia) was studied.