Project description:The aim of this study was to investigate ecotypic adaptation in Holcus lanatus in plants selected from two widely contrasting habitats, acid bog (pH 3.5) or limestone quarry spoil (pH 7.5), using a transcriptome based analysis approach including sequence analysis of root associated Glomeromycota. Differential gene expression in root and shoot of naturally occurring H. lanatus ecotypes, selected from either habitat and grown in a full factorial reciprocal soil transplant experiment were investigated and ecotype specific SNPs identified.
Project description:Thiosulfate- and hydrogen-driven autotrophic denitrification by a model consortium enriched from groundwater of an oligotrophic limestone aquifer
Project description:The leaf transcriptome of the nickel hyperaccumulator Leucocroton havanensis (Euphorbiaceae) living on serpentine Cuabal, from Cuba, was compared to the closely related non-accumulator Lasiocroton microphyllus living on Gallery forest on limestone soil, to identity differentially expressed genes potentially involved in Ni hyperaccumulation.
Project description:The leaf transcriptome of the nickel hyperaccumulator Geissois pruinosa (Rubiaceae) endemic from New Caledonia was compared to the closely related non-accumulator Geissois racemosa, living respectively in serpentine maquis or rainforest on limestone, to identity differentially expressed genes potentially involved in Ni hyperaccumulation.
Project description:A novel contact-separation triboelectric generator concept is proposed in this paper, which consists of a limestone-based mounting putty and a metallized polyester (PET/Al) sheet. This is an attempt to explore tacky materials for power generation and extend the operational frequency bandwidth compared to existing TriboElectric NanoGenerators (TENGs). Moreover, the proposed design is very cost-effective and easy to build. Unlike traditional TENGs, which generate power solely due to a charge developing on the surface, the putty also replies on charge developed inside the material. Parametric study was conducted to determine the optimal putty thickness in a shaker test at 40 Hz. It was found that a putty layer at 0.6 mm thick yielded maximum power generation. During the separation phase, the electrical breakdown between triboelectric layers allows most existing electrons to flow back from the ground due to rapid charge removal at the interface. We are able to achieve a peak power of 16 mW in a shaker test at 40 Hz with an electrical load of 8 MΩ, which corresponds to a power density of 25.6 W/m2. A peak power of 120 mW in a manual prototype generator is achieved, which operates at approximately 2 Hz. Since putty material has less tackiness than double-sided tape, we are able to expand the frequency bandwidth up to 80 Hz, which is significantly higher than a TENG (typically <10 Hz). The mounting putty material contains limestone with approximate 31 nm of mean grain size mixed with synthetic rubber materials. Elasticity from rubber and the nanohardness of calcite crystallites allow us to operate a putty generator repeatedly without the concern of grain fracture. Also, a durability test was conducted with up to 250,000 contact-separation cycles. In summary, comparable performance is achieved in the proposed putty generator to benefit energy harvesting and sensor applications.
Project description:Methane concentration in caves is commonly much lower than the external atmosphere, yet the cave CH4 depletion causal mechanism is contested and dynamic links to external diurnal and seasonal temperature cycles unknown. Here, we report a continuous 3-year record of cave methane and other trace gases in Jenolan Caves, Australia which shows a seasonal cycle of extreme CH4 depletion, from ambient ~1,775 ppb to near zero during summer and to ~800 ppb in winter. Methanotrophic bacteria, some newly-discovered, rapidly consume methane on cave surfaces and in external karst soils with lifetimes in the cave of a few hours. Extreme bacterial selection due to the absence of alternate carbon sources for growth in the cave environment has resulted in an extremely high proportion 2-12% of methanotrophs in the total bacteria present. Unexpected seasonal bias in our cave CH4 depletion record is explained by a three-step process involving methanotrophy in aerobic karst soil above the cave, summer transport of soil-gas into the cave through epikarst, followed by further cave CH4 depletion. Disentangling cause and effect of cave gas variations by tracing sources and sinks has identified seasonal speleothem growth bias, with implied palaeo-climate record bias.
