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Evaluation of Ontario's Environmental Farm Plan (EFP) scheme, launched in 1993, provides an opportunity for comparisons with agri-environmental measures instituted in the European Union and other parts of North America. The EFP has a strong 'bottom-up' dimension in that it is farmers' organizations that have been central both to the scheme's instigation and to its ongoing management. This has affected the nature of the actions taken by individual farmers participating in the scheme. These actions are reviewed, especially in terms of the participants' attitudes towards stewardship of the land, environmental outcomes, cross-compliance measures, barriers to participation and the role of statutory regulation. Some contrasts are drawn with the greater 'top-down' controls exerted in several EU agri-environment schemes, with the latter's promotion of extensification and the changing role of farmers as 'producers of countryside' in a multi-functional agricultural system. The diffusion of EFP schemes throughout Canada is noted and is cited as confirming the maintenance of fundamentally different attitudes to the development of farm-based environmental actions compared with those adopted in the EU.  相似文献   
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Enthalpies of solution have been measured on a series of muscovite—paragonitemicas in 20.1% HF at 50C under isoperibolic conditions. Themolar enthalpy of formation of paragonite at 298 K, for whichno calorimetrically measured value is currently available, hasbeen determined to be –5937.5 (3) kJ. An inversion ofall calorimetric, volumetric and phase equilibrium data hasbeen performed, giving a range of mixing models compatible withmost experimental data. The following expressions of the mixingproperties of 2M1 micas for enthalpy (Hex) and volume (Vex)at pressures up to 10 kbar, forcing excess entropy (Sex) tobe zero and using a subregular mixing model are favoured: Hex(kJ) = [10.6+4.45(1–2Xms)]Xms(1–Xms) Vex(J/bar) = 0.452Xms(1–Xms). However, mixing models of higher order with asymmetric negativeSex are also possible. KEY WORDS: muscovite; paragonite; solvus; calorimetry; solid solution *Corresponding author.  相似文献   
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Facies distributions, stratal geometry and regional erosional bevelling surfaces in Upper Cretaceous (Cenomanian-Santonian) strata of the Alberta foreland basin are interpreted in terms of high-frequency (probably eustatic) relative changes in sea level, superimposed on longer-term basin-floor warping, related to episodic tectonic loading. Thick marine shales correspond to periods of rapid subsidence whereas thin but extensive strandplain sandstones record rapid progradation during slow subsidence. Westward-thickening wedges of coastal plain strata were deposited during initial downwarping of a near-horizontal strandplain, prior to marine transgression. Surfaces of erosional bevelling beneath which between 40 and >160m of strata have been removed extend at least 300 km from the present deformation front and are interpreted to reflect forebulge uplift in the east. Uplift appears to have lagged about 0.25-0.5 Myr behind the onset of accelerated loading. Thin marine sandstones which grade westward into mudstone are interpreted as material winnowed from the crest of the rising forebulge. Subsidence and/or westward migration of the forebulge allowed the sea to flood westward across the eastern flank of the eroded forebulge. The transgressive shoreface cut asymmetric notches which were later blanketed by marine shales which lap out from east to west. The two unconformities which embody the largest erosional vacuity are veneered locally with oolitic ironstone which accumulated in a shallow, sediment-starved setting on the crest of the forebulge. The consistent pattern of erosional bevelling and lap-out of transgressive shales might be interpreted as evidence that the forebulge migrated towards the thrust load over a period of <1 Myr.  相似文献   
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Söderman, G.: Södra Finlands blocksänkor. Geografisk Tidsskrift, 82, 77–81, November 1. 1982.

Map analysis and field inventory show that there are about 20000 boulder depressions in Finland south of 64°N. The features are most common in blocky till areas close to fracture zones in the bedrock. The depressions range in altitude from above the highest shore-line down to 25–30 m above present sea-level. They are youngest in the NW part. Some depressions show surface patterns.

SAMMANDRAG

Blocksänkor är frostmarksformer med en huvudsakligen vertikal sortering som ett resultat av differentiell uppfrysning av blockrikt utgångsmaterial. De framställer inga klimatiska kriteria om utbildningstid och -förhållanden. Däremot här de till områden med sasängbetonad frostaktivitet, och om ej inskränkta till nedisade omräden, trots typiska fär dessa. Blocksänkorna är den mest utbredda och största frostmarksform inom den fennoskandiska skogsregionen i dag.  相似文献   
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Beijing is facing a huge challenge to manage the growth of its built-up area whilst also retaining both productive arable land and land for conservation purposes in order to simultaneously realize the three aims of economic development, protecting arable land and generating environmental improvements. Meanwhile, London, as a world city with more than 200 years of industrialization and urbanization, has accumulated rich theoretical and practical experiences for land use planning in a major urban area, such as the creation of Garden Cities, a designated Green Belt and New Towns. This paper firstly analyzes the main characteristics of the spatial distribution of the built-up area, arable land and conservation land in Beijing. Then, some of the key aspects of urban fringe planning in the London region are examined. Lastly, several implications from the experience of London are provided with respect to land-use planning for Beijing, concentrating on a re-appraisal of land-use functions around Beijing, measures to improve the green belt, the development of small towns to house rural-urban migrants and urban overspill, and effective implementation of land-use planning.  相似文献   
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Book reviewed in this article:
L. Eissmann: Pengladare Prozesse und Permafroststrukturen aus sechs Kalwiten des Quartlrs. Ein Beitrag zur Periglazial-geologie aus der Sicht des Saale-Elbe-Gebietes  相似文献   
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Abstract. Despite the dramatic post-1984 changes in the management of the New Zealand economy, including the establishment of a more diverse pattern of trading partners and products, there remain significant external constraints. New Zealand's position outside major trading blocs is problematic at a time of declining terms of trade for agro-commodities. In this essay, the strategies pursued to improve New Zealand's trading position are considered with special reference to the Uruguay Round of the General Agreement on Tariffs and Trade (GATT), Closer Economic Relations (CER) with Australia, and the promotion of trade liberalisation.  相似文献   
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