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991.
F. J. García Navarro J. A. Amorós Ortiz-Villajos C. J. Sánchez Jiménez S. Bravo Martín-Consuegra E. Márquez Cubero Raimundo Jiménez Ballesta 《Environmental Earth Sciences》2009,59(3):603-611
The study described here involved evaluating the effects that the application of one by-product (sugar foam waste) has upon
red soils in the region of La Mancha (Central Spain). In view of the fact that this is a location where this type of soil
abounds, this technique has been a common practice for many years. The principal goal was to investigate the impact of this
approach on some of the soil properties and, secondly, on its level of fertility. As a result, this represents an investigation
into the effects that this type of waste has on some soil quality parameters. The results showed that, after the addition
of by-products over 25 years, sugar foam waste is of agricultural interest mainly due to the increase in organic matter concentration
(about 2%) and, to a lesser extent, by increases in calcium carbonate (more than 30%) and P (four times more). The soil pH
was also found to increase slightly (1.4), while the electrical conductivity almost did not change. The properties associated
with these pedological qualities therefore had a positive effect by improving nutrient availability. As a result, foams arising
from sugar industries have a positive effect on soil quality and the application of such foams to soils is beneficial since
the need to dispose this residue is also removed. 相似文献
992.
Light-induced reduction of dissolved and particulate Fe(III) has been observed to occur in the surface waters of the acidic
mine pit lake of San Telmo (143,600 m2, pH 2.8, Fetotal = 2.72 mM). This photochemical production of Fe(II) is directly related to the intensity of solar radiation and competes
with biologically catalyzed reactions (i.e., bacterial re-oxidation of Fe(II)) and physical processes (including ionic diffusion,
advection, and convection, which tend to homogenize the epilimnetic concentration of Fe(II) at every moment). Therefore, diel
cycles of Fe(II) concentration are observed at the lake surface, with minimum values of 10–20 μM Fe(II) (0.35–0.70% Fetotal) at the sunrise and sunset, and maximum values of 90 μM Fe(II) (3.2% Fetotal) at midday in August 2005. Field and experimental work conducted in San Telmo and other pit lakes of the Iberian Pyrite Belt
(IPB) (pH 2.3–3.1, Fetotal = 0.34–17 mM) indicate that the kinetics of the photoreductive reaction is zero-order and is independent of the Fe(III) concentration,
but highly dependent on the intensity of solar radiation and temperature. Experimental work conducted with natural Fe(III)
minerals (schwertmannite, goethite, and lepidocrocite) suggests that dissolved organic matter is an important factor contributing
to the photochemical production of Fe(II). The wavelengths involved in the photoreduction of Fe(III) include not only the
spectrum of UV-A radiation (315–400 nm), but also part of the photosynthetically active radiation (PAR, 400–700 nm). This
finding is of prime importance for the understanding of the photoreduction processes in the pit lakes of the IPB, because
the photo-reactive depth is not limited to the penetration depth of UV-A radiation (upper 1–10 cm of the water column depending
on the TDS content), but it is approximately equal to the penetration depth of PAR (e.g., first 4–6 m of the water column
in San Telmo on July 2007); thus, increasing the importance of photochemical processes in the hydro(bio)geochemistry of pit
lakes. 相似文献
993.
The Duna-Tisza Interfluve, Hungary has an agricultural economy but is plagued by severe problems of soil and wetland salinization despite 200 years of intensive research. The study’s objective was to determine the origin of salts and the mechanisms of salinity distribution. To this end, flow-patterns and chemistry of groundwater were evaluated in a 100 km?×?65 km area, with emphasis on the Kolon- and Kelemenszék Lakes region. The lakes are located 13 km apart and have chemically contrasting water and soil types. Two groundwater flow-domains were identified: a gravity-drive meteoric fresh water and an over-pressured deeper domain of saline water. The waters are channeled by a highly permeable gravel aquifer to the surface and may merge near Kelemenszék Lake, causing it to be saline. Kolon Lake receives meteoric groundwater only, hence its fresh chemical character. The cross-formational ascent of the deep waters, combined with the gravitational systems’ geometry and the flow-channeling effect of the near-surface rocks, explains the contrasting chemistry between lakes, and the origin and pattern of soil salinization. The scheme is proposed as a generally valid hydrogeological profile for the interfluve, and has been named the Duna-Tisza Interfluve Hydrogeological Type Section. 相似文献
994.
Integration of hydrogeological and geological data into a conceptual model is critical for site investigation programs, since this model is the basis for hydrogeological modeling and for engineering. In the Hungarian Radioactive Waste Disposal Investigation Program, several methods have been used to characterize the potential host rock (granite) at the Bátaapáti site for a repository for low and intermediate level radioactive waste. Hydrogeological data acquisition revealed some characteristic aspects of the site. One of the most important is the presence of extensive rock deformation zones (faults) with low hydraulic conductivity, which strongly reduce the direct hydraulic communication between adjacent blocks of rock (compartmentalization). This characteristic of the rock mass results in a mosaic-like distribution of rock compartments, each with an almost constant hydraulic head. Within the compartments, hydraulic tests have shown that transmissivity is strongly scale dependent: the larger the scale, the higher the measured transmissivity. The extensive highly transmissive zones cause very low hydraulic gradients within each block, thus the transport processes are strongly influenced by the low or average transmissivity zones and the rock matrix. 相似文献
995.
Kryštof Verner Jiří Žák Jaroslava Pertoldová Josef Šrámek Jiří Sedlák Jakub Trubač Patricie Týcová 《International Journal of Earth Sciences》2009,98(3):517-532
The Plechy pluton, southwestern Bohemian Massif, represents a late-Variscan, complexly zoned intrusive center emplaced near
the crustal-scale Pfahl shear zone; the pluton thus provides an opportunity to examine the interplay among successive emplacement
of large magma batches, magmatic fabric acquisition, and the late-Variscan stress field associated with strike-slip shearing.
The magmatic history of the pluton started with the emplacement of the porphyritic Plechy and Haidmühler granites. Based on
gravity and structural data, we interpret that the Plechy and Haidmühler granites were emplaced as a deeply rooted, ∼NE–SW
elongated body; its gross shape and internal fabric (steep ∼NE–SW magmatic foliation) may have been controlled by the late-Variscan
stress field. The steep magmatic foliation changes into flat-lying foliation (particularly recorded by AMS) presumably as
a result of divergent flow. Magnetic lineations correspond to a sub-horizontal ∼NE–SW finite stretch associated with the divergent
flow. Subsequently, the Třístoličník granite, characterized by steep margin-parallel magmatic foliation, was emplaced as a
crescent-shaped body in the central part of the pluton. The otherwise inward-younging intrusive sequence was completed by
the emplacement of the outermost and the most evolved garnet-bearing granite (the Marginal granite) along the southeastern
margin of the pluton.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
996.
István Cziczer Imre Magyar Radovan Pipík Madelaine Böhme Stjepan Ćorić Koraljka Bakrač Mária Sütő-Szentai Miklós Lantos Edit Babinszki Pál Müller 《International Journal of Earth Sciences》2009,98(7):1741-1766
Life and depositional environments in the sublittoral zone of Lake Pannon, a large, brackish Paratethyan lake from the Late
Miocene, were reconstructed from fossils and facies of the Szák Formation. This formation is exposed in several, roughly coeval
(9.4–8.9 Ma) outcrops, located along strike of the paleo-shelf-break in northwestern Hungary. The silty argillaceous marl
of the formation was deposited below storm wave base, at 20–30 to 80–90 m water depth. The abundance of benthic organisms
indicates that the bottom water was usually well oxygenated. Interstitial dysoxia, however, may have occurred immediately
below the sediment–water interface, as evidenced by occasional preservation of trace fossils such as Diplocraterion. The fauna comprised endemic mollusks, including brackish cockles of the subfamily Lymnocardiinae, dreissenid mussels (Congeria), and highly adapted, uniquely large-sized deep-water pulmonate snails (planorbids and lymnaeids). Ostracods were dominated
by endemic species and, in some cases, endemic genera of candonids, leptocytherids, cypridids, and loxoconchids. Fish remnants
include a sciaenid otolith and the oldest skeletal occurrence of Perca in Europe. The phytoplankton comprised exclusively endemic coccolithophorids, mostly endemic dinoflagellates (prevailingly
Spiniferites), and cosmopolitan green algae. The Late Miocene fauna and flora of Lake Pannon were in many ways similar to the modern Caspian
biota, and in particular cases can be regarded as its precursor. 相似文献
997.
Hans von Storch Eduardo Zorita Fidel González-Rouco 《International Journal of Earth Sciences》2009,98(1):67-82
The performance of statistical climate reconstruction methods in the pre-instrumental period is uncertain, as they are calibrated
in a short instrumental period but applied to much longer reconstructions time spans. Here, the virtual reality created by
a climate simulation of the past millennium with the model ECHO-G is used as a test bed of three methods to reconstruct the
annual Northern Hemisphere temperature. The methods are Composite plus Scaling, the inverse regression method of Mann et al.
(Nature 392:779–787, 1998) and a direct principal-components regression method. The testing methodology is based on the construction of pseudo-proxies
derived from the climate model output, the application of each of these methods to pseudo-proxy timeseries, and the comparison
of their result with the simulated mean temperature. Different structures of the noise have been used to construct pseudo-proxies,
ranging from the simulated grid-point precipitation. Also, one sparse and one denser pseudo-proxy network, co-located with
two real networks, have been considered. All three methods underestimate the simulated variations of the Northern Hemisphere
temperature, but the Composite plus Scaling method clearly displays a better performance and is robust against the different
noise models and network size. The most relevant factor determining the skill of the reconstruction appears to be the network
size, whereas the different noise models tend to yield similar results. 相似文献
998.
Alena Gessert Janetta Nestorová–Dická Ivo Sninčák 《Geografisk tidskrift / udgivet af Bestyrelsen for Det Kongelige danske geografiske selskab》2013,113(2):173-183
Show caves are one of the most important targets in developing local ecotourism strategies. This work focuses on a tourism visit rate incidence through an Attractiveness Index concerning 12 selected show caves in Slovakia. Our study focuses on visitor counts published from 2000 to 2014. A set of eight criteria were selected in order to analyse and determine the appeal that each cave may have for visitors. Establishing the “degree” of appeal as an indicator of the tourism and geographic absolute attractiveness value is based on a principal components factor analysis; the resultant single factor was correlated with our selected criteria. We find a strong correlation between touristic cave attractiveness and cave locations, ease of cave passage access (vehicle and trail) infrastructures, cave location in main tourism regions, and the growth of urban areas as they encroach on show cave locations. Similar studies in valorization of show caves tourism have not been attempted in Slovakia or Eastern Europe. The data and result from this study are also clearly important from a managerial perspective. This general framework could be easily expanded to include additional attributes that might be relevant for other market segments or other vacation experiences. 相似文献
999.
Josef Novotný Jana Kubelková Vanishree Joseph 《Singapore journal of tropical geography》2013,34(3):322-341
This paper provides a multi‐dimensional analysis of the impacts of the Indian Mahatma Gandhi National Rural Employment Guarantee Scheme using a case study from rural Tamil Nadu. Drawing on structured interviews in households and semi‐structured interviews with local employers and officials, we analyse the effects of the workfare scheme when it is widely and properly implemented. We distinguish between different conceptualizations of the work scheme as a means of welfare provision, labour market policy and intervention directed towards other objectives. We found that the goals of the scheme were fulfilled unevenly in the given context. Among other findings, we show that positive effects on the welfare of participating and non‐participating households were accompanied by adverse effects on the local economy and negligible impact on out‐migration for work. 相似文献
1000.
Abstract According to recent research, one of the most promising strategies for intraurban job growth lies promoting localized clusters that produce goods and services which are primarily sold within a single city, metropolitan area, or urban region. However, in order to design urban policies to create or reinforce local clusters, the first challenge is to measure in a reliable way the clustering tendencies of different kinds of economic units in intraurban space. The aim is to compare the similarities and differences in results obtained from two methods designed to measure global clustering tendencies (the planar and network K-functions) in terms of characterization, scale, and intensity of intraurban localization patterns for tertiary economic units in a Latin American metropolis. It is concluded that the network K-function is a more appropriate method for measuring agglomeration patterns, scale, and intensity at the intra-urban level. 相似文献