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Public policy concerning groundwater is often complex, with diverse competing interests. With many countries facing similar challenges, it is instructive to examine the policy approaches that have and have not worked abroad. This article contributes to an international exchange of ideas on how best to approach these common problems by explaining how Sweden regulates its groundwater resources. From constitutional foundations to the practical details associated with applying existing policy, a synopsis is provided of groundwater jurisprudence in Sweden. Multiple governmental agencies are involved with groundwater policy in Sweden; this decentralized approach is probably a function of the natural abundance of clean aquifers throughout the country. Historically, the easy accessibility of high-quality groundwater made it a low priority in the context of environmental policy. It has simply never been an economic necessity to control groundwater resources through a single, unified governmental agency. Sweden is lagging behind many industrialized countries when it comes to implementing policies that protect and manage groundwater. Despite this, there are elements of Sweden’s approach that are highly innovative and possibly unique globally and which therefore merit discussion. 相似文献
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It is shown that a cylindrical plasma column supporting a longitudinal fieldB
z
and an azimuthal fieldB
has a fastest-growing mode in whichkR
01 (k=wave number,R
0=radius of the column). If we assume that plasma is ejected from a galaxy to form a jet, filament or bridge of length 5 kpc,R
00.5 kpc, density 10–24 gm cm–3 with a dragged-out field of strengthB
z
10–5 Gauss (from a parent field 10–6 Gauss), such a column must eventually fragment by the action of a hydromagnetic instability, breaking up into a number 10 of regularly-spaced condensations. It is, therefore, predicted that features like the M87 jet should show incipient nucleation with 3–10 knots, and that periodically-spaced objects of the type noted by Arp may have resulted from the action of such an instability. 相似文献
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Aksel Ersoy 《The Professional geographer》2016,68(1):138-148
This article examines the distribution of the headquarters of top 500 large industrial enterprises in Turkey. It contributes to the knowledge of economic geography by examining regional clusters of headquarters activity in Turkey. As a country, Turkey's corporations have not been extensively analyzed or integrated into the international economic geography literature especially given the fact that headquarters activities in general are important but understudied in the literature of geography. This study therefore extends the corporate literature further in an international dimension, a priority that has been noted as important in the headquarters literature of geography. It argues that not only does the spatial organization of corporations remain important in urban systems but also that they are linked to the dynamics of local and regional economies within developing countries. It shows that various Turkish cities have distinctive internal structures comprising agglomerations of different industries. Although some of these industries are better performing in big cities, the majority of the cities in the top 500 large enterprises list underperform on average. 相似文献
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The interaction of dust grains with each other in a finite-temperature solar nebula are examined, taking into account the important fact that such grains would carry net steady-state charges like those of grains in interstellar clouds. This charge is given by the well-known Spitzer relation. It provides a screening mechanism that operates during accretion and results in bodies of differing compositions depending on the local temperature in the nebula. In a typical nebula, it is found that planetesimals of 0.1–102-cm size form in a time of order 106–107 years. These planetesimals are of iron and stone and mixed composition in the inner solar system, but of mixed composition only in the outer solar system. The predictions of this type of charged-dust accretion can be compared to known data on meteorites and the composition of the planets. 相似文献
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The influence of subclustering in rich clusters of galaxies is examined using results from numericaln-body experiments. It is found that, under some conditions, the standard virial theorem is satisfied. No physical missing mass is needed because its role is replaced by the gravitational energy of the subclustering. We find that, in the Coma cluster, this effect masquerades as a missing mass about 7 times that of the physical mass, so that the apparent extant virial discrepancy (M
VT/M8) in this cluster is explained. 相似文献
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On the basis of numerical experiments onn-body binding energies we tentatively consider the following hypothesis: If the distance between two galaxies forming a binary system isa
g, and a cluster of galaxies that is substructured in a hierarchical fashion onall scales froma
g upwards has a total massM, then the total gravitational binding energy of the cluster is
TH
= –GM
2/2a
g
. As an explanation for missing masses up to order 100 we test this hypothesis in three different ways, finding remarkable agreement with observation, with no need for physical missing mass. 相似文献
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Corruption and regulatory compliance: Experimental findings from South African small-scale fisheries
Although corruption is often mentioned as an obstacle to fisheries management, its negative effects have seldom been investigated empirically in a systematic manner. This article examines the impact of corruption on regulatory compliance among South African small-scale fishermen. Results from scenario experiments with 181 participants confirm that perceived corruptibility of the enforcing authority corrodes the willingness to comply with regulations. Both grand and petty types of corruption have significant effects. Attitudes related to moral support of the regulations, perceived inclusion in the decision making leading to regulations and an individual record of law breaking all affect the willingness to comply. However, these effects are trumped by the relative size of the negative impact of corruption. These findings underline the importance of curbing corruption involving public officials in the small-scale fisheries sector. 相似文献
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