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1.
The spatial knowledge of the relationships between geodiversity and land use/land cover diversity may become crucial to forming modern land use policies and consequently, it may also become fruitful in regional development. But, there is no work in the literature that emphasises the relationships between geodiversity and land use/land cover diversity, especially in a country like India which has a large variety of abiotic elements and also has a large variety of land use/land cover patterns in its territory and hence, has tremendous scope for such kind of work. Therefore, in the present work to partially fill the research gap, an attempt has been made to explore the relationships between geodiversity and land use/land cover diversity of the Birbhum district, India following the principles of richness index. The spatial correlations between geodiversity and land use/land cover diversity have been examined statistically by applying both correlation and regression analyses. The result shows a linear positive correlation between geodiversity and land use/land cover diversity of the concerned district that implies the fact that the areas of high geodiversity are also associated with the areas of high land use/land cover diversity and vice versa.  相似文献   

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In the past decade progress has been made recognising the contribution that geodiversity makes to biodiversity and society. Scotland's Geodiversity Charter, launched in 2012 and revised in 2017, has attracted the support of almost 100 organisations and encourages signatories to work together to recognise the value of geodiversity and ensure it is managed appropriately and safeguarded. The case study presented here highlights that while there is a real desire to protect sites that are scientifically valuable, significant challenges exist to balance this with societal demand for resources and development. There are also challenges for geoscientists and geoconservation groups to communicate effectively with planning authorities and local communities. The case study also sheds light on the problems associated with the systems of designating geosites of national and regional importance, the maintenance of these systems, and how the value of these sites is conveyed beyond the scientific community. Scotland's Geodiversity Charter offers a framework that stakeholders can use to work in partnership to increase awareness of the issues and help achieve the sustainable management of geosites. Case studies such as Callander provide lessons and solutions to overcome the challenges that arise and highlight the need for the participation of both national and local stakeholders.  相似文献   

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Maidl  Elisabeth  Bresch  David N.  Buchecker  Matthias 《Natural Hazards》2021,105(2):1861-1890
Natural Hazards - Building a culture of risk is an essential objective within the integrated risk management paradigm. Challenges arise both due to increasing damage from natural hazards and the...  相似文献   

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We use a geographically weighted regression (GWR) approach to examine how the relationships between a set of predictors and prenatal care vary across the continental US. At its most fundamental, GWR is an exploratory technique that can facilitate the identification of areas with low prenatal care utilization and help better understand which predictors are associated with prenatal care at specific locations. Our work complements existing prenatal care research in providing an ecological, place-sensitive analysis. We found that the percent of the population who was uninsured was positively associated with the percent of women receiving late or no prenatal care in the global model. The GWR map not only confirmed, but also demonstrated the spatial varying association. Additionally, we found that the number of Ob-Gyn doctors per 100,000 females of childbearing age in a county was associated with the percentage of women receiving late or no prenatal care, and that a higher value of female disadvantage is associated with higher percentages of late or no prenatal care. GWR offers a more nuanced examination of prenatal care and provides empirical evidence in support of locally tailored health policy formation and program implementation, which may improve program effectiveness.  相似文献   

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Kirishites are highly carbonaceous hairlike fibers 30–100 μm in thickness and 3–30 mm long, which jut out as bunches on the surface of cinder and shungite fragments associated with volkhovites (Holocene tectitelike glasses corresponding to the rocks of kimberlite-lamproite-carbonatite series in composition). Kirishite fibers are zonal. Their inner (axial) zone is composed of high-nitrogen proteinlike compounds, whereas the outer zone is essentially carbonaceous, with a high content of organoelemental complexes (Si, Fe) and numerous micrometer-sized anomalies of major, volatile, trace, and ore elements. Longitudinal zoning is established in aposhungite kirishites: the consecutive change of maximum concentrations—K, Na, Cl, C, Mn → C, S, V, Ni, Cu, Zn → S, N, Ba, Te, Pb, Bi, Nd—is traced from the roots of fibers to their ends. It is suggested that as volkhovites were forming, fragments of cinder and shungite underwent partial melting. The highly carbonaceous compounds released due decompression and explosion were squeezed out from fragments and solidified as fibers during fall of fragments on the Earth’s surface.  相似文献   

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Computational Geosciences - Rapidly changing heterogeneous supercomputer architectures pose a great challenge to many scientific communities trying to leverage the latest technology in...  相似文献   

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Cadmium has been determined by β-correction spectrophotometry with cadion,p-nitrobenzenediazoaminoaz-obenzone,and a non-ionic surfactant,tuiton X-100.The real absorbance of a Cd-cadion chelate in the colored solution can be accurately determined and the complex-ratio of cadion with Cd(II) has been worked out to be 2.Beer‘s law is obeyed over the concentration range of 0-0.20mg/1 cadmium and the detec-tion limit for cadmium is only 0.003mg/1.Satisfactory experimental results are presented with respect to the determination of trace cadmium in wastewaters.  相似文献   

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Computational Geosciences - A Correction to this paper has been published: https://doi.org/10.1007/s10596-021-10065-y  相似文献   

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Summary The new mineral bellbergite, (K, Ba, Sr)2Sr2Ca2(Ca, Na)4Al18Si18O72 · 30H2O, has been found in Ca-rich xenoliths at the Bellberg volcano near Mayen, Eifel, Germany. It occurs as well formed bipyramids with a length up to 0.3 mm. Possible space groups are P63/mmc, P62c and P63mc with a = 13.244(1) Å, c = 15.988(2) Å, V = 2429 Å3, Z = 1. The density is: Dm, = 2.20(2) Mg/m3, Dc = 2.19 Mg/m3. The empirical formula based on 72 oxygen atoms is: Ba0.26Na0.72K1.33Sr2.36Ca5.32Al17.55Si18.36O72 · 30H2O. The mineral is uniaxial negative with = 1.522(2) and = 1.507(2) ( = 589 nm). The strongest lines in the X-ray powder pattern are (d (Å), I, hkl): 3.80 (100) (300, 212, 104), 6.58 (80) (102), 2.95 (70) (312, 214), 2.21 (70) (330), 2.70 (50) (402), 2.50 (50) (410, 314), 1.83 (50) (416). The crystal structure corresponds to the zeolite structure type EAB.
Bellbergit—ein neues Mineral mit dem Zeolith-Strukturtyp EAB
Zusammenfassung Das neue Mineral Bellbergit, (K, Ba, Sr)2Sr2Ca2(Ca, Na)4AlP18OPub72· 30H2O, wurde in Ca-reichen Xenolithen am Bellberg bei Mayen, Eifel, Deutschland gefunden. Es kommt als gut ausgebildete hexagonale Dipyramiden mit einer Länge von bis zu 0.3 mm vor. Mögliche Raumgruppen sind P63/mcc, P62c und P63mc mit a = 13.244(1) Å, c = 15.988(2) Å, V = 2429 Å3 und Z = 1. Die Dichte beträgt Dm = 2.20(2) Mg/m3, Dc = 2.19 Mg/m3. Die chemische Formel basierend auf 72 Sauerstoffatomen lautet: Ba0.26Na0.72K1.33Sr2.36Ca5.32Al17.55Si18.36O72 · 30H2O. Das Mineral ist einachsig negativ mit = 1.522(2) und = 1.507(2) ( = 589nm). Die stärksten Linien des Pulverdiagramms liegen bei (d(Å), I, hkl): 3.80 (100) (300, 212,104), 6.58 (80) (102), 2.95 (70) (312, 214), 2.21 (70) (330), 2.70 (50) (402), 2.50 (50) (410, 314), 1.83 (50) (416). Die Kristallstruktur entspricht dem Zeolith-Strukturtyp EAB.


With 1 Figure  相似文献   

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The vertical variability in mineralogical, chemical and isotopic compositions observed in large river suspended sediments calls for a depth-integration of this variability to accurately determine riverine geochemical fluxes. In this paper, we present a method to determine depth-integrated chemical particulate fluxes of large rivers, based on river sampling along depth-profiles, and applied to the Amazon Basin lowland tributaries. The suspended particulate matter (SPM) concentration data from depth-profiles is modeled for a number of individual grain size fractions using the Rouse model, which allows to predict the grain size distribution of suspended sediment throughout the whole river cross-section. Then, using (1) the relationship between grain size distribution and the Al/Si ratio (2) relationships between the Al/Si ratio and the chemical concentrations, the chemical composition of river sediment is predicted throughout the river cross-section, and integrated to yield the depth-integrated chemical particulate flux for a number of chemical elements (e.g. Si, Al, Fe, Na, REEs, …). For elements such as Al, Fe, REEs, Th, the depth-integrated flux is around twice as high as the one calculated from river surface sample characteristics. For Na and Si, the depth-integrated flux is three times higher than the “surface” estimate, due to the enrichment of albite and quartz at the bottom of the river. Depth-integrated 87Sr/86Sr composition of suspended sediment, also predictable using this method, differs by more than 10−3 from the surface sample composition.Finally, potential implications of depth-integrated estimates of Amazon sediment chemistry are explored. Depth-integration of particulate 87Sr/86Sr isotopic ratios is necessary for a reliable use of Sr isotopes as a provenance tracer. The concept of steady-state weathering of a large river basin is revisited using depth-integrated sediment composition. This analysis shows that, in the Amazon Basin river, the previously observed discrepancy between (1) weathering intensities of channel surface sediment and (2) silicate-derived dissolved fluxes is only slightly accounted for by the vertical variability of suspended sediment weathering intensities. This observation confirms that most large rivers basins are not eroding at steady-state.  相似文献   

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Variations in elastic wave velocity, low-frequency internal friction and acous-tic emission in granite were experimentally studied as a function of temperature.It is found that the wave velocity and Young‘s modulus tend to decrease with temperature.In association with the α-β transition of quartz a sharp internal friction peak can be recognized accompanied by a drastic drop in wave velocity and modulus and by a second peak of acoustic emission rate.  相似文献   

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A new, simple and highly sensitive kinetic method for the determination of trace iron (III) has been developed based on the catalytic effect of iron (III) on color reaction ofp-amino-N, N-dimethylaniline dihydrochloride (p-DMA) oxidated by hydrogen peroxide. The reaction is followed spectrophotometrically by measuring the absorbance at 510 nm. The detection limit is 4.47×10−11 g/ml, and the calibration curve is linear in the range of 0–0.10μg Fe(III) /25 ml with a relative standard deviation of ±3.25%. The method has been applied to the determination of iron in tap-water, chemical reagents and human hair.  相似文献   

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Inequalities are no respecter of countries, including the affluent ones. Nevertheless, these problems appear to prevail more in the developing countries, which have the dubious distinction of having the highest degrees of inequalities in the world. Inequalities exist between urban and rural areas, as well as between the various regions. This paper discusses inequalities in Ghana and Zimbabwe, emphasizing the rural–urban dichotomy. Using data from the Ghana Demographic and Health Surveys (GDHS) and the Zimbabwe Demographic and Health Surveys (ZDHS) conducted by the respective statistical authorities of both countries and Macro International, the paper analyses existing inequalities in both countries. The paper also attempts to elucidate and understand the causes. It concludes that the traditional explanation of disparities that attribute the conditions to aberrations in the operations of market forces, while having some validity, may not provide a full explanation for Ghana and Zimbabwe’s predicament. It argues that whilst the existing disparities may be rooted in history, their persistence and worsening in the post-independence era could only be understood with reference to the corruption, nepotism and the mismanagement that have characterized these states since they gained their independence.  相似文献   

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Summary The development of mining subsidence, from the immediate roof to the surface, has a dynamic character and it is related to the progress of underground mining and time. Subsidence prediction methods which can pre-calculate the final and intermediate stages of this process are important in mine design. In this paper a prediction method proposed by Knothe (1953), and based on Gauss distribution of influences and Mitsherlich's law of limited increase, is presented and applied to determine the subsidence development over time in the Appalachian coalfield. The method has yielded very promising results and it was verified for a number of longwall case studies.  相似文献   

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Observational data on the evolution of quasars and galaxies of various morphological types and numerical simulations carried out by various groups are used to argue that low-redshift (z < 0.5) quasars of types I and II, identified with massive elliptical and spiral galaxies with classical bulges, cannot be undergoing a single, late phase of activity; i.e., their activity cannot be “primordial,” and must have “flared up” at multiple times in the past. This means that their appearance at low z is associated with recurrence of their activity—i.e., with major mergers of gas-rich galaxies (so-called wet major mergers)—since their lifetimes in the active phase do not exceed a few times 107 yrs. Only objects we have referred to earlier as AGN III, which are associated with the nuclei of isolated, late-type spiral galaxies with low-mass, rapidly-rotating “pseudobulges,” could represent primordial AGNs at low z. The black holes in such galaxies have masses M BH < 107 M , and the peculiarities of their nuclear spectra suggest that they may have very high specific rotational angular momenta per unit mass. Type I narrow-line (widths less than 2000 km/s) Seyfert galaxies (NLSyIs) with pseudobulges and black-hole masses M BH < 107 M may be characteristic representatives of the AGN III population. Since NLSyI galaxies have pseudobulges while Type I broad-line Seyfert galaxies have classical bulges, these two types of galaxies cannot represent different evolutionary stages of a single type of object. It is possible that the precursors of NLSyIs are “Population A” quasars.  相似文献   

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Natural Hazards - Due to excessive harvesting of underground water resources in many important aquifers inside Iran, ground subsidence is occurring at different speeds. In present study, InSAR...  相似文献   

20.
A review with 227 references of the title subject is presented. It is divided into two main sections, viz., nature and properties of humic matter, and water—metal—sediment interactions.The first section deals with the essential properties of organic matter which occurs naturally in drainage sediments and waters. Discussion of the basic molecular structure of humic and fulvic acids is followed by some details of the chemical nature of functional groups within these structures which are important in metal-ion adsorption and complexing reactions which these materials can undergo. Information is also presented for colloidal and polyelectrolyte properties, complexation properties, and finally a summary discussion of metal-ion—humic-acid, metal-ion—fulvic-acid stability constants for both single ligand and mixed ligand systems completes the section.The second section comprises discussions of some specific aspects of interactions between metals, sediments and waters, including metal and organic speciation studies; sorption interactions between organic matter, clays and humic acids; chemical reaction between humic acids, heavy-metal minerals, clays and other silicate minerals; metal-ion adsorption—desorption studies, oxidation—reduction reactions between metal ions and humic acids; effects of sulphide ion on some of the above interactions and finally a summary of some relevant field geochemical dispersion studies.This second section describes both laboratory and field studies for each aspect.  相似文献   

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