Paleoproterozoic molassoid complexes of southwestern Ghana     

N. A. Bozhko  T. K. Adu  M. Yu. Kravtsova 《Moscow University Geology Bulletin》2016,71(6):385-394

The lithology, sedimentation conditions, tectonic evolution features, and mineralization of molassoid complexes in southwestern Ghana that fill the Tarkwa and Bui basins located within the Birrimian Paleoproterozoic orogenic belt are described on the basis of an analysis of published and our own data. The formation of these sediments in geodynamic conditions of pull-apart basins is described. The deposits of the Tarkwa group are compared with the Archean Timiskaming group of the Superior Province and similar younger complexes. The Tarkwa group is considered as the Paleoproterozoic equivalent of molasse-like complexes that formed at the last stage of accretion orogens of different ages in pull-apart structures.  相似文献   

An editorial synthesis of the ACEP project: Ecosystem Processes in the KwaZulu-Natal Bight     

ST Fennessy  MJ Roberts  RG Barlow 《African Journal of Marine Science》2016,38(1):S217-S223

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Integrated Futures for Europe’s Mountain Regions: Reconciling Biodiversity Conservation and Human Livelihoods   总被引：1，自引：1，他引：0  

Jonathan Mitchley  Martin F.Price  Joseph Tzanopoulos 《山地科学学报》2006,(4)

Introduction Europe's mountains cover nearly half of the continent's area (Price et al. 2004) and land cover varies significantly (European Commission 2004). In most massifs, except for Sicily, southern Greece, and the British Isles, forest cover is dominant. In northern Europe, grassland is proportionately more important, and much of the mountains of the British Isles is covered by moorland. In central and southern Europe, arable land is of far greater importance than grassland, with Med…  相似文献   

REMOTE SENSING RESEARCH IN GEOGRAPHY AT MOSCOW UNIVERSITY     

Yu. F. Knizhnikov  V. I. Kravtsova 《地理信息系统科学与遥感》2013,50(3):240-244

A paper describing activities of the Laboratory of Remote Sensing Methods at Moscow University presents a chronology of the Laboratory's efforts to improve sensor capabilities for acquiring remote sensing data and to develop more effective image processing techniques. Among the accomplishments cited are early advances in sensor system design and photochemical processing in conjunction with “Salyut” orbital station activities, multispectral imaging experiments in conjunction with high-resolution space photography from the Soyuz-12 (1973) and Soyuz-22 (1976) missions, testing of the first high-resolution Soviet (“Fragment”) scanner imagery (1984), and ongoing work in digital and applied image processing. Translated from: Vestnik Moskovsskogo Universiteta, geografiya, 1987, No. 2, pp. 27-31.  相似文献   

Urban land use mapping: A case study of ahmedabad city and its environs     

SK Pathan  VK Shukla  RG Patel  BR Patel  KS Mehta 《Journal of the Indian Society of Remote Sensing》1991,19(2):95-112

Proper urban planning and effective implementation requires reliable urban land use statistics. In this context, satellite remote sensing data has been studied using both visual and digital techniques. A portable eight-band radiometer has been used to collect spectral signatures of surface features present in Ahmedabad city and its environs. Using these signatures a suitable approach employing visual and digital techniques has been developed for urban land use/sprawl mapping. Urban land-use maps of Ahmedabad city and its environs were prepared on 1:25,000 scale and for Ahmedabad Urban Development Authority Area on 1:50,000 scale using this methodology. It has been found that edge-enhancement techniques are useful to enhance the contrast among different urban land uses. Classification techniques such as MXL and Bayes classifiers are not successful in discriminating urban land uses. Tonal characteristics alongwith other elements of interpretation are required to classify urban land uses such as residential, industrial etc. Spatial distribution of various urban and uses and the space devoted to each urban land use has been brought out.  相似文献   

A TEST OF SIGNIFICANCE FOR PARTIAL LEAST SQUARES REGRESSION   总被引：1，自引：0，他引：1  

IAN N. WAKELING  JEFF J. MORRIS  AFRC Institute of Food Research  Earley Gate  Whiteknights Ro  Reading RG EF  U.K.Zeneca Pharmaceuticals  Mereside  Alderley Park  Macclesfiel  Cheshire SK TG  U.K. 《地理学报(英文版)》1993,(4)

Partial least squares (PLS) regression is a commonly used statistical technique for performingmultivariate calibration, especially in situations where there are more variables than samples. Choosingthe number of factors to include in a model is a decision that all users of PLS must make, but iscomplicated by the large number of empirical tests available. In most instances predictive ability is themost desired property of a PLS model and so interest has centred on making this choice based on aninternal validation process. A popular approach is the calculation of a cross-validated r~2 to gauge howmuch variance in the dependent variable can be explained from leave-one-out predictions. Using MonteCarlo simulations for different sizes of data set, the influence of chance effects on the cross-validationprocess is investigated. The results are presented as tables of critical values which are compared againstthe values of cross-validated r~2 obtained from the user's own data set. This gives a formal test forpredictive ability of a PLS model with a given number of dimensions.  相似文献   

Variations of Trends in Delta Development under the Effect of External Natural and Anthropogenic Factors: Case Study of the Modern Huang He Mouth     

V. N. Mikhailov  V. I. Kravtsova  A. N. Inyushin  M. V. Mikhailova 《Water Resources》2018,45(4):466-478

The paper considers the major geographic features of the modern Huang He delta, which ranks among the most rapidly varying in the world. The structure of the hydrographic network and the combination of the natural and anthropogenic geosystems of the delta are characterized. The major external riverine and marine, as well as local anthropogenic factors that have affected the development of the Huang He delta in the recent half century are identified. The regularities of the jump-like development of the Huang He delta in the XIX–early XXI centuries are considered. Special attention is paid to the development of the delta after the artificial redistribution of flow in its boundaries in 1996. Satellite images and methods of their interpretation improved by the authors were used. The trends in Huang He delta development are shown to have changed since the last quarter of the XX century under the effect of an abrupt decrease in river sediment load and the growing impact of marine factors. The active progradation of the delta into the sea slowed down significantly, accompanied by erosion and retreat in many segments of its coastline. Huang He delta was used to establish the conditions of changes in the development trends of other deltas under the effect of changes in the climate and economic activity.  相似文献   

Diagnostics of the electromagnetic characteristics of the interplanetary medium based on cosmic ray effects     

V. M. Dvornikov  M. V. Kravtsova  V. E. Sdobnov 《Geomagnetism and Aeronomy》2013,53(4):430-440

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THE CONCEPT OF AN INTEGRATED REPOSITORY OF SPACE IMAGERY AND NEW CRITERIA FOR ITS GEOGRAPHIC AND CARTOGRAPHIC ANALYSIS     

V. I. Kravtsova 《地理信息系统科学与遥感》2013,50(3):169-178

This paper outlines some principles believed necessary for the establishment of integrated collections of remote sensing imagery, including, at the national level, a unified state image repository for the USSR. A multi-criterion classification of imagery is introduced, which provides a framework for structuring such a repository, and a number of measures for evaluating the utility of imagery within it are described. One of the latter is “geographic” resolution (levels of image detail), which provides a relatively straightforward indication of the type of geographic information embedded within particular types of remote sensing imagery. Translated by Jay K. Mitchell, PlanEcon, Inc., Washington, DC 20005 from: Vestnik Moskovskogo Universiteta, geografiya, 1988, No. 6, pp. 53-62.  相似文献   

Chemotaxonomic investigation of phytoplankton in the shelf ecosystem of the KwaZulu-Natal Bight,South Africa     

RG Barlow  T Lamont  M-J Gibberd  M van den Berg  K Britz 《African Journal of Marine Science》2015,37(4):467-484

Phytoplankton community structure was elucidated during summer and winter in the KwaZulu-Natal Bight using pigment and CHEMTAX analyses. The surface pattern in January 2010 indicated that diatoms, haptophytes and prasinophytes tended to be the most prominent groups inshore and in the southern sector of the bight, whereas Prochlorococcus and Synechococcus were more dominant in the north and towards the offshore region. At the deep chlorophyll maximum (DCM), diatoms were dominant in the inner bight and in the south, with prasinophytes being the prominent flagellates, but this changed to Prochlorococcus and pelagophytes being the important groups in the northern sector and outer part of the bight. A different pattern was observed at the surface in July 2010, where diatoms, haptophytes, prasinophytes and cryptophytes in varying proportions comprised most of the community in the inner half of the bight, whereas Synechococcus and haptophytes were the main groups in the outer sector. A similar pattern occurred at the DCM, except that Synechococcus was less prominent and pelagophytes were distributed across the bight in both the inshore and offshore zones. Observations and relationships between phytoplankton groups and environmental parameters indicated that the groups were most closely related to temperature, accounting for 24–64% of the deviance. The influence of nutrients on phytoplankton was less clear but nitrate and silicate seemed to account for some of the patchy distribution patterns.  相似文献