Ecological strategy for soil contaminated with mercury

Aims The paper presents results from plot experiments aimed at the development of an ecological strategy for soil contaminated with mercury. Meadow grass (Poa pratensis) was tested on mercury contaminated soil in a former chlor-alkali plant (CAP) in southern Poland for its phytoremediation potential. Methods The stabilisation potential of the plants was investigated on plots without additives and after the addition of granular sulphur. Biomass production, uptake and distribution of mercury by plants, as well as leachates and rhizosphere microorganisms were investigated, along with the growth and vitality of plants during one growing season. Results The analysed plants grew easily on mercury contaminated soil, accumulating lower amounts of mercury, especially in the roots, from soil with additive of granular sulphur (0.5 % w/w) and sustained a rich microbial population in the rhizosphere. After amendment application the reduction of Hg evaporation was observed. Conclusions The obtained results demonstrate the potential of using Poa pratensis and sulphur for remediation of mercury contaminated soil and reduction of the Hg evaporation from soil. In the presented study, methods of Hg reduction on “hot spots” were proposed, with a special focus on environmental protection. This approach provides a simple remediation tool for large areas heavily contaminated with mercury

Stratabound Ore Deposits of Hualgayoc, Cajamarca, Peru

Hualgayoc is one of the typical "complex mining districts" of the Central Andes, characterized by the influence of many superimposed geologic events and ore-forming processes It has been worked since Spanish colonial times. Initially, Hualgayoc was famous for the silver ores which were extracted principally from the upper parts of the ore deposits. The zones of oxidation and supergene enrichment of many deposits have already been removed by early mining. With time, the production of the district became more polymetallic (zinc, lead, and copper as well as silver). Many mines are being operated by several small companies and some mining ventures of the "mediana mineria". There are up to five flotation plants, with a total capacity of about 800 t/day. Although this important mining district has been the object of a large number of geologic studies by many geologists, we are far from understanding the origin of many of its ore deposits, especially those of the stratabound type. The purpose of this chapter is to describe the geologic, mineralogic and geo- metric characteristics of the stratabound ore deposits of this important district to improve our understanding of the complicated geologic setting of the "mantos". Hualgayoc is situated in northern Peru, at a height of between 3500 m and 2400 m, near, and on the east zone of the continental divide of the Cordillera Occidental

Miniaturized Raman instrumentation detects carotenoids in Mars-analogue rocks from the Mojave and Atacama deserts

NoThis study is primarily focused on proving the potential of miniaturized Raman systems to detect any biomolecular and mineral signal in natural geobiological samples that are relevant for future application of the technique within astrobiologically aimed missions on Mars. A series of evaporites of varying composition and origin from two extremely dry deserts were studied, namely Atacama and Mojave. The samples represent both dry evaporitic deposits and recent evaporitic efflorescences from hypersaline brines. The samples comprise halite and different types of sulfates and carbonates. The samples were analysed in two different ways: (i) directly as untreated rocks and (ii) as homogenized powders. Two excitation wavelengths of miniaturized Raman spectrometers were compared: 532 and 785 nm. The potential to detect carotenoids as biomarkers on Mars compared with the potential detection of carbonaceous matter using miniaturized instrumentation is discussed