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Due to a predicted shortage of raw materials, increasing attention is drawn to the utilization of anthropogenic resources through recycling and urban mining. However, in order to assess the availability of anthropogenic resources as potential raw materials, a consistent concept for categorizing anthropogenic materials into reserves, resources and other occurrences is needed. This study presents a framework for the evaluation of anthropogenic resources, derived from the standard procedure for resource and reserve identification, evaluation, and classification of the U.S. Geological Survey for natural stock resources. The framework was applied to a case study on phosphorus (P) stocks in Austria. Results indicate that only 10% of the anthropogenic P stocks in Austria (one million tons in total) are extractable at subeconomic levels with production costs 5–10 times above the market price for P fertilizer. 70% of P stocks are not technically extractable and 20% of such a low grade that recovery is not practically feasible. Based on the assessment, it is found that the extractable amount of P could have been much higher if P-rich materials were not mixed with low-grade materials during landfilling. Although the evaluation of anthropogenic P stocks in Austria was performed on a screening level, the application of the framework highlights that a consistent method for the evaluation of anthropogenic resources can provide a basis for enhanced utilization of anthropogenic resources. In future, further case studies are needed to demonstrate the application of the evaluation framework for various resources and in consideration of environmental, technological, and societal factors. [ABSTRACT FROM AUTHOR]

Highlights: [•] Nematode standing stocks were mainly driven by temporal effects, rather than depth patterns. [•] Topographic/hydrographic differences are important for nematode standing stock patterns. [•] Nematode size distributions seem driven by food pulses in food-rich areas such as the Blanes Canyon. [•] Food pulses may induce the nematode community into a more ‘reproductive’ state. [•] Food pulses may attract or stimulate smaller, more opportunistic nematode species. [Copyright &y& Elsevier]

We examine the influence of climate, soil properties and vegetation characteristics on soil organic carbon ( SOC) along a transect of West African ecosystems sampled across a precipitation gradient on contrasting soil types stretching from Ghana (15° N) to Mali (7° N). Our findings derive from a total of 1108 soil cores sampled over 14 permanent plots. The observed pattern in SOC stocks reflects the very different climatic conditions and contrasting soil properties existing along the latitudinal transect. The combined effects of these factors strongly influence vegetation structure. SOC stocks in the first 2 m of soil ranged from 20 Mg C ha−1 for a Sahelian savanna in Mali to over 120 Mg C ha−1 for a transitional forest in Ghana. The degree of interdependence between soil bulk density ( SBD) and soil properties is highlighted by the strong negative relationships observed between SBD and SOC ( r2 > 0.84). A simple predictive function capable of encompassing the effect of climate, soil properties and vegetation type on SOC stocks showed that available water and sand content taken together could explain 0.84 and 0.86 of the total variability in SOC stocks observed to 0.3 and 1.0 m depth respectively. Used in combination with a suitable climatic parameter, sand content is a good predictor of SOC stored in highly weathered dry tropical ecosystems with arguably less confounding effects than provided by clay content. There was an increased contribution of resistant SOC to the total SOC pool for lower rainfall soils, this likely being the result of more frequent fire events in the grassier savannas of the more arid regions. This work provides new insights into the mechanisms determining the distribution of carbon storage in tropical soils and should contribute significantly to the development of robust predictive models of biogeochemical cycling and vegetation dynamics in tropical regions. [ABSTRACT FROM AUTHOR]

The article discusses the new type of mineralization which is the gold-bearing explosive breccias of the Vanin stock in Northeastern Russia. It states that Vanin stock was located south of the gold-bearing Natalka deposit and north of the Pavlik deposit which composed of two isolated different-age intrusive complexes. It notes on the gold-bearing explosive breccias of the Vanin stock along with a chart bearing the position of the Vanin stock in the Omchak ore district. It also mentions the characteristics of ore mineralization which are confined to explosive breccias of the Vanin stock which concludes that such provides grounds for taking on development of gold-sulfide ores of the Maiskoe type in the Omchak ore district.

This paper presents results of two-dimensional seismic mapping of the northern East China Sea Shelf Basin. Various igneous features such as sills, volcanic edifices and stocks were identified by the geophysical exploration. The sills are most common, and are observed at more than 90 locations. Most mapped sills in the study area are characterized by high-amplitude continuous reflections with distinct terminations. Saucer- and cup-shaped sills are observed locally. The stocks are discordant (nearly vertical) igneous bodies and they are characterized by seismic transparency, with upturned host rocks and uplifted overburden. The volcanic edifices and/or necks consist of irregular mounds and peaks and are characterized by strong positive top reflections with chaotic internal facies. The oldest igneous activity in the northern East China Sea Shelf Basin is Early Cretaceous (123.3 ± 3.7). This igneous activity coincides with those observed in eastern China which has been related mainly to the subduction of the Pacific Plate beneath Eurasia Plate. The Miocene igneous activity is well constrained based on seismic stratigraphic relationships within the folded stratigraphy, age dating, and the occurrence of igneous sills. The timing of this intrusion is coincident with the intensive igneous activity as previously suggested for the eastern China. Igneous rocks can produce hydrocarbon traps, reservoirs and they can act as a seal, and therefore are of great importance in petroleum study. [ABSTRACT FROM AUTHOR]

Abstract: The major borax producer, Eti Mining Co. of Turkey, planned to construct an export stock site located near the Bandirma Harbor in the northwestern of Turkey. During this construction, some stability problems were encountered. To analyze the stability problems and to assess the engineering properties of soil in the stock site geotechnical investigations were started. As a part of geotechnical investigations one of the most common field tests, the standard penetration tests (SPT), was conducted for soil exploration. In this study, the field is geostatistically simulated to assess the uncertainty associated with the spatial variability of SPT results. Multiple probable realizations of SPT values are generated using sequential Gaussian simulation. Using 122 NSPT data in the borax stockpile site, the characteristics observed in the available data are reproduced in a manner that the heterogeneity of SPT within the field is honored. The estimated NSPT data can also be used for other purposes such as determination of bearing capacity, and estimation of soil strength parameters. [Copyright &y& Elsevier]

Stanniferrous granite-leucogranite massifs in Vietnam to which the bedrock and placer commercial deposits of cassiterite are associated (Timtuc etc.) are of late Cretaceous age (∼85 Ma by Rb-Sr and Ar-Ar isotope dating). These massifs are presented by stocks and fracture intrusions (to 100 km2 in area) of simple homodromic structure: biotite granites ⇒ two-mica and muscovite leucogranites ⇒ topaz-containing aplites ⇒ rare-metal pegmatites. [ABSTRACT FROM AUTHOR]

The material stocks in the anthroposphere are growing faster than ever due to urbanization and growing per capita use. Owing to the growing potential insecurity of raw material supply the evaluation of resources gains increasing attention. Despite growing utilization of anthropogenic deposits, 'urban mining' has not yet sufficiently been supported by specific exploration methods. An exploration method for anthropogenic deposits is proposed and described by application to the copper stocks of Switzerland. The method combines material flow analysis with a bottom-up analysis of material stocks. The stock composition and temporal characteristics are analysed by surveys and literature analysis. The stock amounts to 269±31 kg capita-1 for the year 2000. The retrospective data are used as parameters to construct a dynamic stock model, which is calibrated by historical trade statistics. The potential for drafting scenarios is discussed. The stock situation in Switzerland is reviewed and compared with that of other regions. [ABSTRACT FROM AUTHOR]

Fisheries managers frequently try to protect juveniles in order to preserve stocks. Juveniles can be protected by either implementing changes designed to avoid catching immature animals (e.g. increasing mesh size or altering fishing techniques) or protecting nursery grounds. To prevent the capture of immature animals, an estimate of size at maturity is required as well as a knowledge of both fishing methods and the exact location of the nursery grounds. Strong demand for juvenile mud crabs to stock aquaculture ponds has resulted in development of fisheries targeting crabs of all sizes from instar 1 to mature individuals. Using five different fishing methods, different stages in the life cycle of Scylla paramamosain were followed for a period of 16 months in an estuarine population in the Mekong Delta, Vietnam. Mangrove habitat utilisation begins when crabs settle out from the plankton at instar 1 [modal internal carapace width (ICW), 0.5 cm] amongst the pneumatophores at the mangrove fringe. Increasingly larger crabs were found deeper into the mangrove but they were still living on the surface (modal ICW size class, 1.5 cm). As their size increases, the crabs either dig burrows (modal ICW size class, 4.5 cm) or they live in the sub-tidal zone, migrating into the mangrove with each tide to feed (modal ICW size class, 4.5 cm). Larger crabs were caught offshore (modal ICW size class, 12.5 cm) where females accounted for 60% of the catch although of these, only 63% were mature. Recruitment of early instars was continuous but peaked in December to February. Subsequent peaks in the catch rates of larger size classes indicated the development of a single cohort with an estimated growth rate of 2.0 cm ICW per month. On the basis of abdominal width, females were estimated to mature at 10.2 cm ICW although at 9.7 cm ICW, 50% of females had disengaged abdomens. Abdominal disengagement occurred in males at the slightly smaller size of 9.1 cm ICW. Allometric relationships between chela height and carapace width suggested 50% of males acquire mature chelae at 10.2 cm ICW. These results demonstrate the close linkage between early life stages of S. paramamosain and certain specific niches within mangrove habitats, with the main adult population found to be living sub-tidally at some distance from the mouth of the estuary. The study also highlights the special importance of the mangrove fringe, the border between the mangrove forest and the sea, an area which is particularly vulnerable to physical and anthropogenic impacts. [ABSTRACT FROM AUTHOR]

The analysis of mitochondrial DNA in loggerhead sea turtles ( Caretta caretta) from eight foraging grounds in the Mediterranean and the adjoining Atlantic revealed deep genetic structuring within the western Mediterranean. As a consequence, the foraging grounds off the North-African coast and the Gimnesies Islands are shown to be inhabited mainly by turtles of the Atlantic stocks, whereas the foraging grounds off the European shore of the western Mediterranean are shown to be inhabited mainly by turtles from the eastern Mediterranean rookeries. This structuring is explained by the pattern of sea surface currents and water masses and suggests that immature loggerhead sea turtles entering the western Mediterranean from the Atlantic and the eastern Mediterranean remain linked to particular water masses, with a limited exchange of turtles between water masses. As the north of the western Mediterranean comprises mostly individuals from the highly endangered eastern Mediterranean rookeries, conservation plans should make it a priority to reduce the mortality caused by incidental by-catch in these areas. [ABSTRACT FROM AUTHOR]

Presents a study which analyzed the Alta stock and aureole rocks in Utah to determine the source, composition and physical-chemical conditions of infiltrating fluids. Boron distribution in rocks and minerals from alpha-track mapping; Discussion.