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781.
A. P. Grima Dr. 《GeoJournal》1981,5(5):503-511
This paper focuses on the articulation of policies in the interface between economic production and water quality. One problem
is the introduction, at this production-ecologic interface, of unwanted water-borne residuals by firms and municipalities.
The policy objective is to absorb the social cost of environmental degradation into the production function within the two
constraints of efficiency in the allocation of resources and the protection of property rights. The efficient allocation of
environmental resources (in such a way as to maximize human welfare) has long been recognized as a basic objective in resource
management. Equally important is the consideration of environmental rights and responsibilities in a society where property
power and the institution of property is a dominant characteristic. Since the manner in which the property owner acts may
affect the environment of his neighbours, it is important that policy instruments inform the holder of the property rights
of the ill-effects of his actions upon others and induce him to take action to remedy the situation.
The question of water quality management options requires urgent consideration for two reasons. Firstly, the cost of water
pollution control is already considerable and is likely to increase even more sharply as the growing number of urban centres
put greater pressure on the water resource for waste dilution and assimilation and other competing uses such as municipal
demands, heat dissipation, recreation and wildlife protection. Secondly, the institutional mechanisms for dealing with this
problem seem to be inadequate and ineffective. It is true that subsidies and grants have encouraged the building of more municipal
waste treatment plants while regulation and court action have reduced some of the worst abuses.
Subsidies and grants may be inefficient policy choices because they encourage hardware solutions even when other less expensive
solutions are possible. In addition, they fail to inform the polluters of the ill-effects of their action; and the general
public has to shoulder the burden in the form of increased taxation. Regulation and court action are cumbersome, sporadic
and time-consuming.
Effluent standards could be made flexible as a policy instrument if they afforded the polluter the opportunity to choose either
to install in-plant controls or to pay the “fine” or to combine both these choices in any way that minimized his costs. This
would combine the policy instrument of the effluent standard with the policy instrument of an effluent (or user) charge. The
charges could be set either to reflect marginal pollution damages or the marginal cost of maintaining a given ambient standard.
In other words the inferred marginal damage of pollution is equal to the marginal cost of treatment up to some desired level
thus ensuring that the desired amount of waste load be reduced at least cost. Pricing and transferable effluent permits serve
the same purpose. 相似文献
782.
Dr. Luis Dalla Salda 《International Journal of Earth Sciences》1981,70(3):1030-1042
Metamorphic and granitoid rocks of the El Cristo area, southern part of Tandilia Range, are considered in terms of structural, lithological and geochronological data.The abovementioned area was affected before 2000 m. y. by a first tectono-thermal event that was followed by a second episode of intense SW-NE folding. The latter accompanied or followed by a metamorphism of almandine grade and strong synkinematic to latekinematic granitization during the span 1800-1520 m. y.Succeeding episodes of metamorphism and deformation were less intense and culminated in the local development of a 900 m. y. granite, chloritization and some brittle deformation.
Zusammenfassung Tektonische, lithologische und geochronologische Daten der metamorphen und granitischen Gesteine der El Cristo Gegend im südlichen Teil des Tandilia Gebirges werden diskutiert.Vor mehr als 2000 Ma wurde dieses Gebiet erstmals von einem tektonothermalen Ereignis erfa\t, gefolgt von einer zweiten Episode starker SW-NE gerichteter Faltung. Letztere wurde begleitet oder gefolgt von einer Almandingrad Metamorphose und starker synbis spÄtkinematischer Granitisierung wÄhrend der Zeitspanne 1800 bis 1520 Ma.Darauffolgende Metamorphosen und Deformationsereignisse waren weniger intensiv und endeten um 900 Ma in Lokaler Granitintrusion, Chloritisierung und spröder Deformation.
Résumé Des roches métamorphiques et granitoÏdes de la région de Cristo font ici l'objet d'une discussion sur la base de données structurales, lithologiques et géochronologiques.La région mentionnée a été marquée d'abord, il y a plus de 2000 millions d'années, par une phénomène thermo-tectonique, suivi, dans une seconde phase, d'un plissement important dirigé SO-NE. Celui-ci a été accompagné ou suivi par un métamorphisme à almandin et par une intense granitisation syncinématique à tardicinématique au cours de la période 1800-1500 m. a.Des épisodes de métamorphisme et de déformation moins intenses s'ensuivirent, qui aboutirent au développement local, vers 900 m. a., d'une intrusion granitique, avec chloritisation et déformations cassantes.
, - , 2000 - , SW-NE. 1800 1520 . , 900 .相似文献
783.
Independence,dependence and fragmentation in the South Pacific 总被引:1,自引:0,他引:1
J. Connell Dr. 《GeoJournal》1981,5(6):583-588
Since the 1960s most island groups of the South Pacific have achieved independence and many new nations have been established; only the very smallest islands remain colonies. Most of the small nations are extremely small yet secession movements in many areas have resulted in fragmentation producing the break-up of the Gilbert and Ellice Islands and the disintegration of the Trust Territory of the Pacific Islands. This has emphasized the distinctive characteristics of the Pacific nations: their small size (in population and in area) and limited natural resources, their isolation from each other and from markets and fragmentation within multiple island countries. The extension of outside interests into the Pacific has brought rapid economic changes, the emergence of cash cropping and the decline of subsistence agriculture, increased dependence on imports (especially food, resulting in some nutritional problems) and rapid urbanization, producing growing dependence and inequality which regional ties between the Pacific nations have not been able to overcome. Outmigration from the smallest nations to USA and New Zealand is likely to be maintained and the unusual characteristics of these small island nations suggest that strategies of development that appear viable elsewhere have little chance of success in the Pacific. 相似文献
784.
Dr. F. Scordari 《Mineralogy and Petrology》1981,28(3):207-222
Summary This paper deals with some unsolved crystal chemical questions concerning a group of alkali iron hydrated sulphates based on clusters of composition [Fe
3
3+
O(SO4)6(H2O3]5– Taking the experimental chemical formulae, X-ray data and known crystal structures into account it is possible to establish the theoretical boundaries of the Na–K diadochy in metavoltine and also to define the influence of the Na–K replacement on the structure of -Maus' salt. These considerations allow us to propose more general crystal chemical formulae, both for metavoltine and -Mous' salt. Finally, the causes which affect the stability of metavoltine and and -Maus' salt are discussed.
With 6 Figures 相似文献
Kristallchemische Überlegungen zu einigen wasserführenden Alkali-Sulphaten
Zusammenfassung Diese Arbeit befaßt sich mit einigen noch ungelösten kristallchemischen Fragen einer Gruppe von wasserführenden Alkali-Eisen-Sulphaten, die auf Gruppierungen der Zusammensetzung [Fe 3 3+ O(SO4)6(H2O)3]5– basieren. Aufgrund der experimentall ermittelten chemischen Formeln, Röntgendaten und der bekannten Kristallstrukturen ist es möglich, die theoretischen Grenzen der Na–K Diadochie in Metavoltin zu ermitteln. Außerdem gelang es, den Einfluß des Na–K Ersatzes auf die Struktur des -Maus'schen Salzes zu definieren. Diese Überlegungen führten dazu, allgemeine chemische Formeln sowohi für Metavoltin wie für -Maus'sches Salz vorzuschlagen. Schließlich werden die Faktoren diskutiert, die die Stabilität von Metavoltin sowie von und -Maus'schem Salz bestimmen.
With 6 Figures 相似文献
785.
R. Mull Dr.-Ing. 《GeoJournal》1981,5(5):473-481
In many areas, the water demand of households, industries and farms is satisfied by ground water. Because of many human activities
ground-water quality decreases, it is necessary to protect it. The quantity of pollutants entering the aquifers can be minimized
by technical and legal measures. But it seems to be almost impossible to solve the problem regionally or nationwide. The delineation
of protection zones around existing or planned wells is a more effective way.
The intake area of wells or well fields have to be protected by legal measures against all activities which may affect ground-water
quality. Regarding the migration of viruses and bacteria, it is well known that these biological pollutants have a distinct
limited lifetime in aquifers, which is for West Germany estimated at 50 days. Because during this limited time they can move
with the ground water, transfer diseases, and cause epidemics, certain zones around wells must be kept free from activities
which may introduce bacteria into the subsurface systems. These zones are generally smaller than the catchments. For the determination
of the zones, careful studies and calculations of the distance-velocity of ground water are necessary. Primary methods are
the use of tracers and simple calculations. Examples are given for calculating the distance to the 50-day line, based on West
German experience. 相似文献
786.
Occurrence frequency of unusual weather caused by anomalous synoptic patterns has its peaks in the middle latitude regions
and the subtropical regions. Height anomaly patterns at the 500 mb level for the last three decades show the expansion of
negative area in the northern hemisphere, resulting in increase of variability in space and time. 相似文献
787.
788.
Following a tentative evaluation of palynological information from Ladinian and, more particularly, Karnian successions, there seems to be every indication that qualitative and quantitative compositional differences of palynological assemblages could well be applied in testing concepts of Triassic phytogeography and palaeoclimatology. The following implications are emphasized:
- There is sufficient palynological evidence that the Mediterranean region includes a domain of mixed northern (Laurasian) and southern (Gondwana) types of floras.
- The concept of an essentially arid nature of a wide equatorial climatic belt during Triassic times finds palynological support.
- Palynological evidence does not contradict a concept of pronounced decrease in precipitation towards the western part of the Mediterranean region.
- In Europe, occurrences of hygrophytic palynofloras and coals within an arid climatic zone can be explained by the water-supply of extensive river-systems.
789.
Prof. Dr. Walter Kertz 《International Journal of Earth Sciences》1981,70(1):15-32
Zusammenfassung Ausgangspunkt der Wegenerschen Theorie war der unmittelbare Eindruck von der Kongruenz der atlantischen Küsten. Das eigentliche Fundament bildeten jedoch die Argumente aus Paläontologie, Geophysik, Geologie, Paläoklimatologie und Astrogeodäsie. Wegener war nicht nur der Schöpfer, sondern auch der Propagandist seiner Theorie. Von bleibendem Wert erwiesen sich seine Forderungen: Jede Theorie der Entstehung der Ozeane und Kontinente muß von allen geowissenschaftlichen Disziplinen getragen werden und sie muß sich durch Messungen bestätigen lassen.
The starting-point of Wegener's theory was the direct impression of the congruity of the Atlantic coastlines. The fundamental principle, however, is formed by the argumentation of paleontology, geophysics, geology, paleoclimatology and astrogeodesy. Wegener was not only the creator of his theory but he also propagated it. His demands proved to be of lasting value: every theory of the origin of oceans and continents has to be supported by all geosciences and it should be possible to be verified by physical measurements.
Resume Le point de départ de la théorie de Wegener fut l'impression immédiate de la concordance des côtes atlantiques. Les bases véritables furent les arguments tirés de la Paléontologie, de la Géophysique, de la Géologie, de la Paléoclimatologie et de l'Astrogéodésie. Wegener fut non pas seulement le créateur de sa théorie, mais encore son propagandiste. Sa démarche reste valable d'une théorie de la genèse des continents et des océans qui soit étayée part toutes les sciences de la terre et verifée par des mesures physiques.
. , , , . , . , , .相似文献
790.
S. I. Okafor Dr. 《GeoJournal》1981,5(4):385-390
Conclusions In general terms, this paper has demonstrated how the expansion of public facilities can be phased and implemented within the framework of certain policy objectives. Given an existing network of hospitals, for instance, it is possible to plan and implement the provision of additional facilities in a manner that enhances the spatial efficiency of the expanded network. The expansion can be executed in such a way that with the addition of each new facility, not only is aggregate travel minimized, but also a specified proportion of the population can be brought within easy reach of hospital services. This method is a particularly useful one because in planning the location of facilities, authorities hardly ever start off with a clean slate. Usually some facilities of the same kind might already be occupying some locations which may or may not be optimal. But whether or not the already existing network is optimal, the overall efficiency of the expanded network can be enhanced by proceeding in the manner outlined above.This method can be applied to a wide range of public facilities, like schools for instance. But its application depends, among other things, on the clear definition of locational and policy objectives. Different objectives could produce different locational patterns. Even variations in the measures of distance used can produce different locational patterns. 相似文献