Stable isotope and trace element status of subsistence-hunted bowhead and beluga whales in Alaska and gray whales in Chukotka

Tissues of bowhead, beluga, and gray whales were analyzed for Ag, Cd, Cu, Se, Zn, THg and MeHg (belugas only). Delta15N and delta13C in muscle were used to estimate trophic position and feeding habitat, respectively. Trace element concentrations in tissues were significantly different among whale species. Hepatic Ag was higher in belugas than bowheads and gray whales. Gray whales had lower Cd concentrations in liver and kidney than bowhead and belugas and a sigmoid correlation of Cd with length was noted for all whales. Renal and hepatic Se and THg were higher in belugas than in baleen whales. The hepatic molar ratio of Se:THg exceeded 1:1 in all species and was negatively correlated to body length. Hepatic and renal Zn in subsistence-harvested gray whales was lower than concentrations for stranded whales. Se:THg molar ratios and tissue concentrations of Zn may show promise as potential indicators of immune status and animal health.     

Sedimentation rate of soil microparticles

The aim of the submitted paper is to identify the lower limit of Stokes’ law for calculating the deposition rate of soil microparticles. The authors’ hypothesis on the lower limit of Stokes’ law is based on the idea that with the gradual formation of the colloidal dispersion system, both the particle size and the sedimentation rate decrease. It is assumed that under the lower particle size limit, Stokes’ law does not apply. As a result of the diffusion, the state of the sedimentation equilibrium gradually emerges. The results of the experiment showed that in laboratory conditions, Stokes’ equation ceases to be valid for sedimentation of the particles sized d(90)?<?2 μm. During the experiment, a dynamic sedimentation equilibrium was reached at the particle size d(90)?=?0.27 μm. The scientific contribution of this knowledge is the accuracy of the determination of hydropedological characteristics dependent on the texture of the soil. In this context, the results stated in the paper define the lower limit of the validity for the laboratory procedures determining soil texture on the basis of the sedimentation methods. To identify the textures below this limit, it is necessary to choose the methods based on other principles. Determination of the lower limit is particularly important in clay soils containing a high proportion of clay particles (clay particles <?2 μm).     

Lateral variation in gravelly sediments and processes in an alluvial fan-fan-delta setting,north of Durgapur

Sedimentological study of the digitated lobes of gravel and associated sediments in the north of Durgapur results in identification of five major facies. Facies analysis indicates the sediments were deposited from an alluvial fan that has prograded in to an inferred shallow body of water. The analysis also suggests debris flow deposits dominate proximal part, modified grain flow and turbidity current the middle part and current generated channel and non-channel deposits in the distal part of the alluvial fan — fan-delta sequence.     

Ecological metrics and methods for GPS movement data

The growing field of movement ecology uses high resolution movement data to analyze animal behavior across multiple scales: from individual foraging decisions to population-level space-use patterns. These analyses contribute to various subfields of ecology – inter alia behavioral, disease, landscape, resource, and wildlife – and facilitate novel exploration in fields ranging from conservation planning to public health. Despite the growing availability and general accessibility of animal movement data, much potential remains for the analytical methods of movement ecology to be incorporated in all types of geographic analyses. This review provides for the Geographical Information Sciences (GIS) community an overview of the most common movement metrics and methods of analysis employed by animal ecologists. Through illustrative applications, we emphasize the potential for movement analyses to promote transdisciplinary GIS/wildlife-ecology research.     

Peak Minerals: Theoretical Foundations and Practical Application

This article reviews the theoretical foundations for the concept of peak minerals; drawing on similarities and differences with peak oil as modelled using Hubbert style curves. Whilst several studies have applied peak modelling to selected minerals, discussion of the appropriateness of using Hubbert style curves in the minerals context remains largely unexplored. Our discussion focuses on a comparison between oil and minerals, on the key variables: rates of discovery, estimates of ultimately recoverable resources and demand and production trends. With respect to minerals, there are several obstacles which complicate the application of Hubbert style curves to the prediction of future mineral production, including the lack of accurate discovery data, the effect of uncertain reserve estimates, and varying ore quality and quantity. Another notable difference is that while oil is often combusted during use, minerals are used to make metals which are inherently recyclable. Notwithstanding, by using a range of estimates of resources and/or reserves, a period of time can be identified which indicates when a peak in minerals production may occur. This information may then be used to plan for a transition from using a potentially constrained resource, to using substitutes if available, or to reducing demand for that mineral in society.