Evaluation of MIVIS Hyperspectral Data for Mapping Soil Degradation in an Upland Ecosystem of Southern Italy

Abstract

This paper describes the first stage of an experiment aiming to evaluate the potential and limitations of MIVIS data for mapping the degradational state of soils in a sub‐scene of a southern Apennines study area (Italy). After radiometric rectification of the image data and the collection of a field/laboratory spectral library, linear spectral mixture modelling (SMA) was used to decompose image spectra into fractions of spectrally distinct mixing components. Spectral endmember selection was based upon a principal component analysis (PCA) applied to a set of soil spectra, collected from the spectral library. The resulting abundance estimates (fractions) trough SMA were then analysed to identify soil conditions and to obtain an improved measure of dry and green vegetation cover. A map of soil conditions and dry‐green vegetation abundance, based upon MIVIS data was then derived from normalised fractions of soil‐vegetation endmembers obtained from SMA.     

A Practical Procedure for the Measurement of Fragmentation by Blasting by Image Analysis

Summary. The operation of a digital image analysis system in a limestone quarry is described. The calibration of the system, required in order to obtain moderately reliable fragmentation values, is done from muckpile sieving data by tuning the image analysis software settings so that the fragmentation curve obtained matches as close as possible the sieving. The sieving data have also been used to extend the fragment size distribution curves measured to sizes below the system’s optical resolution and to process the results in terms of fragmented rock, discounting the material coming from a loose overburden (natural fines) that is cast together with the fragmented rock. Automatic and manual operation modes of the image analysis are compared. The total fragmentation of a blast is obtained from the analysis of twenty photographs; a criterion for the elimination of outlier photographs has been adopted using a robust statistic. The limitations of the measurement system due to sampling, image processing and fines corrections are discussed and the errors estimated whenever possible. An analysis of consistency of the results based on the known amount of natural fines is made. Blasts with large differences in the amount of fines require a differentiated treatment, as the fine sizes tend to be the more underestimated in the image analysis as they become more abundant; this has been accomplished by means of a variable fines adjustment factor. Despite of the unavoidable errors and the large dispersion always associated with large-scale rock blasting data, the system is sensitive to relative changes in fragmentation.     

Paleozoic plume-lithospheric processes in northeastern Fennoscandia: Evaluation of the composition of the parental mantle melts and magma generation conditions

The paper reports quantitative evaluations of the modal and chemical composition of the mantle whose Paleozoic activation gave rise to the Kola alkaline province in the northeastern Baltic Shield. The volume of alkaline magmatism within the province and the volume of the mantle melts that were generated in the course of the Paleozoic activation cycle were evaluated by three-dimensional density modeling on the basis of gravimetric data. Our studies involved, along with the sampling of alkaline magmatic rocks in the region, the examination of the deep (to a depth of 22.5 km) structure of all alkaline intrusions in the province and the development of their three-dimensional density models. Concentrations of trace elements were precisely analyzed by the ICP-MS technique, and these data were used in order to calculate the weighted mean concentrations of trace elements in rocks of the province, to simulate the melting of mantle sources, and to evaluate the geodynamic sequences of these mantle processes. Our simulations indicate that the total volume of the Paleozoic mantle melts in the northeastern part of the Baltic Shield amounted to 15000 ± 2700 km³. The calculated composition of the partial melts that could be produced by the mantle of average composition shows the necessity for the significant introduction of certain elements into the mantle source. It is demonstrated that primitive melts in the Kola province were highly probably derived at low degrees of melting of the source (0.3–0.5%), whose composition corresponded to phlogopite-bearing (±amphibole) garnet lherzolite under the conditions of the mantle garnet depth facies. The calculated degree of enrichment of this sources was three times higher than the average concentrations of incompatible elements in the primitive mantle. It is demonstrated that magma generating processes affected much of the lithosphere beneath northeastern Fennoscandia and reached a depth of 120 km, i.e., the depth of the mantle facies of garnet lherzolite. The area of this region corresponds to the area of regional Paleozoic magmatism, and its depth correlates with the estimated P-T conditions under which the mantle xenoliths found in regional diatremes were formed.     

Protein Digestibility by Khosti Fish Colisa fasciatus (Pisces,Anabantidae) under the Influence of Certain Factors

Protein digestibility was determined via two feeding trials in glass aquaria by the indicator (Chromium oxide) method using a mixture of shrimp powder with oil cake and wheat bran respectively (1: 1 W/W) as food. Analyses of feed were made to calculate the crude protein, carbohydrate, lipid and ash contents. Feces were analysed to determine their total nitrogen and chromium oxide. Protein digestibility was studied in relation to salinity of the medium size and weight of the fish body. The apparent digestibility of crude protein of a corresponding die has shown that 1st: Younger fish do possess a lower capability of protein digestion than fish having a medium weight and medium size; 2nd: Older fish with a high weight and large size exhibit no improvement in efficiency to digest the food protein, though their weight and size are significantly greater than those of middle weight and medium size fish; 3rd: The replacement of oil cake by wheat bran decreases the protein digestibility of shrimp powder mixture with them; 4th: A salinity (NaCl) of the aquatic medium at or above 3 g/l depletes the protein digestibility when fish of the same size were experimented with; but a salinity up to 2 g/l does not result in a significant decrease in the protein digestion rate.     

Erosion rates and mechanisms of knickzone retreat inferred from 10Be measured across strong climate gradients on the northern and central Andes Western Escarpment

A steep escarpment edge, deep gorges and distinct knickzones in river profiles characterize the landscape on the Western Escarpment of the Andes between ~5°S and ~18°S (northern Peru to northern Chile). Strong north–south and east–west precipitation gradients are exploited in order to determine how climate affects denudation rates in three river basins spanning an otherwise relatively uniform geologic and geomorphologic setting. Late Miocene tectonics uplifted the Meseta/Altiplano plateau (~3000 m a.s.l.), which is underlain by a series of Tertiary volcanic‐volcanoclastic rocks. Streams on this plateau remain graded to the Late Miocene base level. Below the rim of the Meseta, streams have responded to this ramp uplift by incising deeply into fractured Mesozoic rocks via a series of steep, headward retreating knickzones that grade to the present‐day base level defined by the Pacific Ocean. It is found that the Tertiary units on the plateau function as cap‐rocks, which aid in the parallel retreat of the sharp escarpment edge and upper knickzone tips. ¹⁰Be‐derived catchment denudation rates of the Rio Piura (5°S), Rio Pisco (13°S) and Rio Lluta (18°S) average ~10 mm ky^?1 on the Meseta/Altiplano, irrespective of precipitation rates; whereas, downstream of the escarpment edge, denudation rates range from 10 mm ky^?1 to 250 mm ky^?1 and correlate positively with precipitation rates, but show no strong correlation with hillslope angles or channel steepness. These relationships are explained by the presence of a cap‐rock and climate‐driven fluvial incision that steepens hillslopes to near‐threshold conditions. Since escarpment retreat and the precipitation pattern were established at least in the Miocene, it is speculated that the present‐day distribution of morphology and denudation rates has probably remained largely unchanged during the past several millions of years as the knickzones have propagated headward into the plateau. Copyright © 2011 John Wiley & Sons, Ltd.     

Neoproterozoic events in the Tcholliré area: Pan-African crustal growth and geodynamics in central-northern Cameroon (Adamawa and North Provinces)

The Rei Bouba Group is a sedimentary and volcanic sequence (750–?650 Ma), regarded as a remnant of a Pan-African (back-arc?) orogenic basin that separated a remobilized Paleoproterozoic crust from an accretionary area (Poli Complex: 800-650 Ma). The latter was subjected to early deformation (D1) and intruded by calc-alkalic plutons (670 Ma). Transpressive tectonics and major thrusting, with emplacement of synkinematic granite, occurred at ca 630 Ma (D2-3) and a late compression (D4), with emplacement of calc-alkalic granite, occurred at ca 570 Ma. The Tcholliré Shear Zone is regarded as part of the major boundary between a recently accreted crust and the remobilized margin of the Congo Craton.     

Biochemical‐genetic and meristic evidence that blue and copper moki (Teleostei: Latridae: Latridopsis) are discrete species

Specimens of blue moki Latridopsis ciliaris (Forster in Bloch & Schneider, 1801) from New Zealand were shown to differ from specimens of copper moki Latridopsis forsteri (Castelnau, 1872) using two genetic methods—allozymes and muscle proteins. Allozyme techniques revealed fixed differences between blue and copper moki at 4 out of 15 loci. There was a genetic distance of 0.31–0.34 between population samples of the two colour morphs. The two morphs were also distinguished by iso‐electric focusing of muscle proteins. Meristic characters, counted in the specimens studied with genetic markers, revealed diagnostic markers in tubed lateral line scales and scales in the lower transverse series. It is concluded that specimens of blue moki from New Zealand and copper moki from New Zealand and Tasmania are valid species.     

Dynamic simulation of littoral zone habitats in low Chesapeake Bay. II. Seagrass habitat primary production and water quality relationships

Seagrasses are indicators of ecosystem state because they are sensitive to variations in water composition and clarity resulting from watershed-level impacts. A simulation model designed to studyZostera marina (eelgrass) habitat dynamics in a variable littoral zone environment was used to address the potential ecological responses to eutrophication in lower Chesapeake Bay. The adjacent channel boundary environment is a source of dissolved and particulate materials to the littoral zone. In the simulations, concentrations of key water quality variables in the adjacent estuarine channel boundary were either halved or doubled relative to the base case to investigate light versus nitrogen effects. The role of the seagrass meadow in littoral zone carbon and nitrogen dynamics was evaluated when meadow size was changed in the model. Particulate and dissolved organic carbon accounted for 83% of the submarine light attenuation in the seagrass meadow. In all model runs, the water column concentrations of chlorophylla and dissolved inorganic nitrogen (DIN) were below the habitat criteria proposed as critical to seagrass survival. Eelgrass community production was carefully regulated by the interactive effects of light, nitrogen, and grazing on epiphyte growth. Increased eelgrass coverage in the littoral zone led to a simulated doubling of ecosystem primary production but reduced the fraction of production by planktonic and sediment microalgae. The simulation model presented here demonstrated the importance of material input from the channel in littoral zone biogeochemical dynamics. Submarine ligh regulated primary production more strongly than inorganic nitrogen concentrations in the model. External DIN concentrations influenced seagrass survival indirectly: enrichment stimulated growth of epiphytes and phytoplankton and promoted shading of the seagras leaf. The model was based upon a unimpacted ecosystem and deteriorated water quality negatively influenced primary production greater than the increases triggered by improved condition. Increased material loading to the littoral zone reduced submarine light availability, increased phytoplankton production, lowered ecosystem production, and reduced subtidal vegetated habitat. This simulation model of the estuarine littoral zone model combines hydrodynamics, biogeochemical sources and sinks, and living resources in order to better understand structure, function, and change in aquatic ecosystems.     

Diagenetic development of unstable and stable magnetization in the St. Bees Sandstone (Triassic) of northern England

Thermal demagnetization of red and drab sandstones from the St. Bees Sandstone shows a wide range of directional stability. After the removal of a metastable secondary magnetization at temperatures up to 300°C red sandstones may show stable or unstable magnetization. Experiments indicate that both the stable and unstable magnetization is carried by coarse haematite particles (specularite).Drab sandstones, which have been subject to reduction and dissolution of haematite are generally unstable but specimens with a stable NRM occur and this must be carried by specularite because the pigment has been removed from these specimens.The stable magnetization is believed to have developed during deposition and early diagenesis by the oxidation of detrital iron oxides. Pole positions correspond to known Triassic poles and there are abundant normal and reversed zones typical of the Lower Triassic.The unstable magnetization of the red sandstones is apparently due to the development of authigenic overgrowths of haematite on the detrital specularites. This phase of authigenesis may have taken place over a long time, and after significant changes in the ambient geomagnetic field resulting in complex magnetizations in individual grains and hence whole rocks.     

Reconstruction of Holocene Environmental Changes in North-Western Pacific in Relation to Paleorecord from Shikotan Island

Doklady Earth Sciences - Results of a paleolimnological investigation of a well-dated lake sediment section from Shikotan Island (Southern Kurils) showed that from ca 8.0 to 5.8 cal ka BP a warm...