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1.
《Geoforum》1987,18(2):187-202
The main critiques of the term ‘region’ were directed in the 1950s against the ‘uniqueness’ of the region: being not repetitive, it was considered not to be of general value. In the author's opinion the term ‘uniqueness’ was misinterpreted: a region is made unique by the unique relationship between natural, cultural, economic, political and social elements existing in it. However, as these relationships are repetitive, or some at least can be repeated, regional geography is of general value. If the geographical study of a region invests its efforts and interests in functions, processes and relationships between the elements existing in a region, the concept of a region becomes, in fact, a concept of a system, with epistemological and methodolgical consequences. A model of ‘region as a system’ is the approach taken in this paper. Such an approach can resolve some basic problems of geography: the dichotomy between natural and anthropic elements of the region, which cannot be treated except by a systems approach; the tension existing between ‘space’ and ‘place’, which is perpetuated by the dichotomy between regional and systematic geography. Through a systems approach, the choice of a scale appropriate to a particular study can be directed by a distinction between system and subsystem; inclusion or exclusion of an element in the study of a region is not an arbitrary one, but depends on its relevance to the processes within the region. Perhaps the ‘personality of the region’, so often misinterpreted by scorners of regional geography, can be accepted as a legitimate part of the regional output.  相似文献   

2.
The paper by Perry et al. (2007, Defining biominerals and organominerals: Direct and indirect indicators of life, Sedimentary Geology, 201, 157–179) proposes to introduce “the new term ‘organomineral’” to describe mineral products whose formation is induced by by-products of biological activity, dead and decaying organisms, or nonbiological organic compounds, to be distinguished from the biomineral components of living organisms. The substantive ‘organomineral’, however, is not new: it was first introduced in 1993, with basically the same definition and distinction from biominerals, at the 7th International Symposium on Biomineralization (Défarge and Trichet, 1995, From biominerals to ‘organominerals’: The example of the modern lacustrine calcareous stromatolites from Polynesian atolls, Bulletin de l'Institut Océanographique de Monaco, n° spéc. 14, vol. 2, pp. 265–271). Thereafter, more than twenty-five papers by various authors have been devoted to organominerals and organomineral formation (‘organomineralization’) processes. Only two of these papers are cited by Perry et al., and without any reference to the definitions, or even the terms ‘organomineral’ or ‘organomineralization’, which they included. Moreover, Perry et al. tend to enlarge the original concept of organomineral to encompass all minerals containing organic matter, whether these organic compounds are active or passive in the mineralization, which introduces ambiguities detrimental to a fine understanding of present and past geobiological processes. Finally, Perry et al. propose to consider organominerals as indirect biosignatures that could be used in the search for evidence of life in the geological record and extraterrestrial bodies. This latter proposition also is problematical, in that organominerals may be formed in association with prebiotic or abiotic organic matter.  相似文献   

3.
Of the many diverse sources of naturalistic thinking in early modern geography, the penetration of Darwinian evolution is conventionally regarded as one of the most influential. In its application to social processes, the term ‘Social Darwinism’, as it is generally designated, has been used to describe almost any evolutionary perspective on human society. In its most common form, ‘Social Darwinism’ (or ‘Business Darwinism’, as some have designated it) has been portrayed as an attempt to provide ‘scientific’ justification for the cut-throat ethics of late nineteenth century capitalism. The main contention of this essay is that the widespread use of the term ‘Social Darwinism’, has obscured the variety of other ways in which biological analogies were applied to society, and that one of the most influential of these was the social model erected on the Lamarckian evolutionary alternative — a version of evolutionary biology widely espoused by geographers in Britain and America. Social Lamarckism, by emphasizing the cumulation of social improvements, repudiated the non-interventionism of ‘Social Darwinism’ and was used by many geographers to underpin their support for numerous educational, eugenic and environmental movements to improve the condition of humanity. And while biologically bankrupt, the Lamarckian social schema continues to be invoked as a viable model of society's evolution.  相似文献   

4.
The term‘Ediacara Biota’(or many variants thereof)is commonly used to refer to certain megascopic fossils of Precambrian and early Palaeozoic age e but what does the term actually mean?What differentiates a non-Ediacaran‘Ediacaran’and an Ediacaran‘Ediacaran’from an Ediacaran non-‘Ediacaran’?Historically,the term has been used in either a geographic,stratigraphic,taphonomic,or biologic sense.More recent research and new discoveries,however,mean that the term cannot actually be defned on any of these bases,or any combination thereof.Indeed,the term is now used and understood in a manner which is internally inconsistent,and unintentionally implies that these fossils are somehow distinct from other fossil assemblages,which is simply not the case.Continued use of the term is a historical relic,which has led in part to incorrect assumptions that the‘Ediacara Biota’can be treated as a single coherent group,has obscured our understanding of the biological change over the PrecambrianeCambrian boundary,and has confused research on the early evolution of the Metazoa.In the future,the term‘Ediacaran’should be restricted to purely stratigraphic usage,regardless of affnity,geography,or taphonomy;suffcient terminology also exists where reference to specimens on a geographic,taphonomic,or biologic basis is required.It is therefore time to abandon the term‘Ediacara Biota’and to instead treat equally all of the fossils of the Ediacaran System.  相似文献   

5.
Although often critical of the results achieved by rural planners, research by geographers and others has for some time been constrained by an inability to isolate the precise impacts of planning procedures on rural areas. The notions of a technically solvable ‘implementation problem’ and a politically complex ‘policy problem’ are confronted here, and acknowledgement of the latter directs research into the realms of decision-making and policy-implementation iteration in rural areas. Key themes in the understanding of these matters are those of central-local state relations, inter-agency relations and public-private sector relations, all of which should figure prominently in any conceptualisation of policymaking and implementation in rural areas. One final factor which invites conceptual clarification is that of the specificity of rurality as a policy-moulding phenomenon. The idea is introduced of a ‘rural dimension’ which presents a spatial facade to aspatial structures and processes.  相似文献   

6.
《Gondwana Research》2014,25(2):707-728
Methods for species recognition and delimitation based solely on morphological characters are presented. Species can be described as pools of contemporarily interconnected genotypes possessing their own history leading to evolutionary lines. Interconnection in genotypes is expressed by homogeneous phenotypes, but not in a one to one relation. The proof of interconnection by phenotypic homogeneity must be based on the four criteria ‘shape homogeneity’, ‘ontogenetic cohesion’, ‘homogeneous ecological niches’ and ‘evolutionary continuity’. While in all eukaryotes, three of the four – homogeneities in shape and ecological niches, ontogenetic cohesion – can be checked both in living individuals and fossil forms, the detection of birth (speciation), lifetime and death (ending) of a species, factors that determine an evolutionary line, is only possible in organisms with a fossil record. Speciation can be grouped in split-off and split-up processes. Split-off processes where a daughter species derives from a mother species are easier to recognize than split-up processes where several species originate more or less contemporaneously within a geological time interval. This makes it difficult to delimitate species when they are in a reticulate speciation process in which hybridization between subspecies is a common feature. In contrast to evolutionary continuity, homogeneities in shape and ecological niches as well as ontogenetic cohesion are more difficult to recognize in fossil species due to low specimen numbers, incomplete preservation caused by taphonomic processes and the fragmentary representation of fossil environments in the sedimentary strata, hindering the acquisition of gradients. Nevertheless, the four criteria enable the recognition of species without molecular–genetic investigations. Only the combination of these criteria makes identification of species in the fossil record possible.  相似文献   

7.
Ocean plate stratigraphy (OPS) is essential to understanding accretionary wedges and complexes along convergent plate margins. Mélanges within accretionary wedges and complexes are the products of fragmentation and mixing processes during and following OPS accretion. A new term, ‘OPS mélange’, is proposed here for mélanges composed mostly of blocks of OPS with an argillaceous matrix, and for a mixture of mélanges of multiple origins with either broken or coherent formations. An OPS mélange results from the fragmentation and disruption of OPS, without admixing of other components. Three major types of OPS mélange can be distinguished on the basis of their components: turbidite type, chert–turbidite type, and limestone–basalt type. These three types potentially form similar mélanges, but they are derived from different parts of the OPS, depending on the level of the decollement surface. The concept of ‘OPS mélange’ can be applied to most of the mélanges in accretionary prisms and complexes worldwide. In addition, this proposal recognizes a distinction between processes of fragmentation and mixing of OPS components, and mixing of ophiolite components, the latter of which results in serpentinite mélanges, not OPS mélanges. Mélanges composed of OPS sequences occur worldwide. The recognition of OPS mélanges is a key aspect of understanding tectonic processes at convergent margins, which result in mélange formation in orogenic belts globally.  相似文献   

8.
The last few decades have seen increasing attempts to foster ‘collaborative’ and ‘participatory’ approaches to spatial planning and decision-making, with a more sophisticated conceptualisation of the contested term, participation. Participatory, ‘bottom-up’ geo-information technologies have been concurrently developing and these are expected to strengthen participatory spatial planning; important among these has been the transformation of conventional mapping and GIS tools into Participatory GIS (PGIS). In this paper we explore the potential contributions of participatory geo-information tools towards participatory spatial planning, in terms of the principles and criteria of good governance. We discuss five fundamental principles of ‘good’ governance: accountability, legitimacy, respect, equity, and competence, and the potential of geo-information tools to contribute to, and detract from, such principles; although we focus especially on participation and the recognition and validation of local knowledge. We derive criteria for the five principles, and we identify a range of evaluation questions which can be operationalised so as to interrogate the criteria for judging the contribution of participatory tools and participatory spatial planning activities. We conclude by summarily assessing the potentials of participatory geo-information tools, particularly participatory mobile GIS, participatory 3-dimensional modelling, and visualisation features in PGIS.  相似文献   

9.
The Anthropocene deposits of England, here regarded as those formed after ～1950 CE, are now extensive, take various forms, and may be characterized and recognized by a number of stratigraphic signals, such as artificial radionuclides, pesticide residues, microplastics, enhanced fly ash levels, concrete fragments and a novel variety of ‘technofossils’ and neobiotic species. They include the uppermost parts of both ‘natural’ deposits such as the sediment layers formed in lakes and estuaries, and more directly human-made or human-influenced ones such as landfill deposits and the ‘artificial ground’ beneath urban areas and around major constructions. ‘Negative deposits’ include the worked areas of quarries and regions such as the English Fenland, where thick peat deposits have ablated to leave a strongly modified underlying landscape, and extend beneath into the subterranean realm as mine workings, metro systems and boreholes. The production of these is still rapidly increasing and evolving in character, while the early signs of global change, such as warming, sea level rise, and modifications to biotic assemblages, are beginning to further modify the emerging geology of this new phase of Earth history.  相似文献   

10.
The Lower to Middle Ordovician Guniutan (Kuniutan) Formation in the eastern Yangtze Gorges, China has been demonstrated to be similar to the ‘Orthoceratite Limestone’ in Baltoscandia with respect to facies, stratigraphic development and conodont biostratigraphy. Thus the ‘Orthoceratite Limestone’ appears to be a much more widely distributed and characteristically Ordovician facies than has hitherto been assumed. Five lithostratigraphic subdivisions of the Guniutan Formation are here defined in ascending order as the Nanya, Puxi, Wuguixi, Daping and Niangjiafang members. It is shown that these members, which represent considerable spans of time as indicated by their conodont stratigraphy, may be fairly thin but nevertheless regionally extensive. A new conodont zone, with Eoplacognathus crassus as the zonal fossil, is established to accommodate the precise dating of the Wuguixi and Puxi members. Microfacies data from the Guniutan Formation, available for the first time, show that its dominant component particles are sand-sized echinoderm and arthropod debris, as in the Baltoscandian ‘Orthoceratite Limestone’.  相似文献   

11.
Acheulean sites are commonly recovered from sandy channel contexts, particularly in Africa. These sites frequently contain impressive concentrations of artifacts dominated by typical Acheulean large bifacial artifacts (‘handaxes,’ etc.). Possible influences of fluvial sedimentary processes in Acheulean site formation are explored through consideration of sedimentary context and detailed analysis of relevant artifact assemblage characteristics in part of a major Acheulean ‘Floor’ at Kalambo Falls, Zambia. The Kalambo Falls patterns are analyzed here with regard to influences of behavioral and natural processes in their formation, and are compared to those observed in Acheulean horizons at Montagu Cave, South Africa. Spatial concentration of bifaces and paucity of debitage at many Acheulean sites may be due largely to fluvial disturbance and winnowing, although a hominid preoccupation with large bifacial tools may be a bona fide behavior pattern at some sites. Better control over sedimentary context is necessary to elucidate the range of behaviorally-produced patterns at Acheulean sites.  相似文献   

12.
Scale is a debatable term in the humanities and social sciences. Conceptualized in human geography as spatial categories of thought, as the arenas where social processes occur, as bounded political-economic frames or as unhelpful binaries privileging either the local or the global, scale intersects a significant body of geographical research. The unfolding and intermeshing of topological connections that help to share moments and experiences are important sources for the differentiation, renewal and recalibration of individual identities, but they often work as co-components to scalar identifications. Engaging with the recent discussion on scale and the upsurge of emotional geographies, I seek to understand how people contextualize space through situated scalar perspectives and how they realign and recognize their identities through embodied emotions. The analysis of the empirical material, that comprises 23 focus groups with locally and universally-orientated civic organizations in Finland and England, focuses on the ways people use landscapes and communities as emotional signposts in their scalar identification. I argue that scale is a situated category, whose spectrum individuals negotiate through the performance of social discourses and cultural practices. In such negotiation, people scale their identity narratives to overcome or emphasize the distinctions between ‘us’ and ‘others’.  相似文献   

13.
Fundamental data on the residual saturation of incompressible filter cakes which have been drained by vacuum have been measured. The effects of varying particle size, shape and distribution, type of wetting fluid and cake size have been assessed. A modified ‘threshold pressure’, below which dewatering will not occur, has been defined and an index reflecting the nature of the particles and their packing has been used to represent reduced saturation data. Irreducible saturation levels have been correlated against a capillary number, and by careful definition of the driving force term data scatter have been substantially reduced.  相似文献   

14.
A chaotic fault interaction model previously developed for the San Andreas Fault System and the Nankai Trough (examples of transform fault and subduction dominated tectonic regimes, respectively) is here applied to the large-event seismicity in the New Zealand region, where the interacting blocks of the model are taken to be those parts of the Indo-Australian plate boundary that are, from north-east to southwest, subduction dominated, ‘transpressional’, and transform-fault dominated. The model suggests a shorter term recurrence of large events than do simple seismic cycle approaches.  相似文献   

15.
The microstructures of turbiditic and hemipelagic muds and mudstones were investigated using a scanning electron microscope to determine whether there are microstructural features that can differentiate turbiditic from hemipelagic sedimentary processes. Both types of muddy deposits are, in general, characterized by randomly‐oriented clay particles. However, turbiditic muds and mudstones also characteristically contain aggregates of ‘edge‐to‐face’ contacts between clay particles with long‐axis lengths of up to 30 μm. Based on observations of the clay fabric of the experimentally‐formed muds settled from previously agitated muddy fluids, these types of aggregates, hereafter referred to as ‘aggregates of clay particles’, are interpreted as having been formed by the collision of component flocs in turbulent fluids. Furthermore, some aggregates of clay particles have ‘face‐to‐face’ contacts between clay particles; this is similar to face‐to‐face aggregates characteristically developed in fluid‐mud deposits that are commonly recognized only in turbiditic mudstones, indicating the possibility of a final stage of deposition under highly‐dense conditions, such as temporary fluid muds. In conjunction with earlier proposed lithofacies‐based and ichnofacies‐based criteria, aggregates of clay particles should be useful for the differentiation of turbiditic and hemipelagic muddy deposits, particularly with limited volumes of non‐oriented samples from deep‐water successions.  相似文献   

16.
The term ‘rewilding’ sounds as if it should have a straightforward meaning ‘to make wild again’. But in truth the term has a complex history and a host of meanings have been ascribed to it. Rewilding as a specific scientific term has its beginnings as a reference to the Wildlands Project, which was founded in 1991 and aimed to create North American core wilderness areas without human activity that would be connected by corridors. Words, however, do not stand still—they change over time and take on new meanings, while sometimes simultaneously retaining the older sense. Employing Foucault’s idea of historical genealogy, this article examines how the term rewilding was historically adopted and modified in ecological scientific discourse over the last two decades. This investigation probes what and, by extension, when and where, rewilding refers to as it has moved into various geographies across the globe. It then examines how the term has moved outside of science and been adopted by environmental activists as a plastic word. Taken as a whole, rewilding discourse seeks to erase human history and involvement with the land and flora and fauna. Such an attempted split between nature and culture may prove unproductive and even harmful. A more inclusive rewilding is a preferable strategy.  相似文献   

17.
‘New regionalism’ has become a buzzword in current debates on regions and regional governance. Much of this discussion revolves around the ‘right’ scale and structure of regional governance, implying changes to the ways in which the conventional main variables institutions, hierarchy and territoriality interact to circumscribe ‘regions’. The main difference between ‘old’ and ‘new’ regionalism is the degree of variability and responsiveness to locational strategies by businesses, i.e. essentially relative regional competitiveness, and thus by implication the question of territoriality and boundedness. Evidence ‘on the ground’ among policy makers, however, suggests that the changes may go further than theoretical arguments with their emphasis on territory and scale (Brenner, 2000, 2003) are suggesting. Much of the difference revolves around the distinction between technocratic, planning focused and firmly institutionalised understandings of territorially fixed regions within a government structure on the one hand, and more purpose driven, flexible, and inherently temporary and variable arrangements outside fixed government structures, whose territoriality is composed of the varying spatial background of the participating actors. Here, regional territoriality is an incidental rather than determining factor.The cleavage between ‘old’ and ‘new’ regionalism has become particularly obvious in post-socialist eastern Germany, where staid forms of traditional institutionalism and territorial governance had been transferred from ‘west’ to ‘east’. Increasingly, these arrangements appeared inadequate to respond to the vast and spatially widely varying challenges of post-socialist restructuring. The result has been a tentative emergence of new forms of regionalisation in between, and in addition to, the established ‘old regionalist’ approaches. Evidence from eastern Germany suggests that ‘new’ is not necessarily replacing ‘old’ regionalism’ in the wake of a shift in paradigm, but rather that the two coexist, with new forms of regionalisation sitting within established conventional territorial-administrative arrangements. This points to the emergence of a dual track approach to regionalisation, sometimes covering the same territory, more often relating to variably sized areas that overlap. Both forms of regionalisation aim at an internal and external audience, using varying images and employing different sets of actors when dealing with the two main sources/directions of consumption: internal (local) and external (corporate, competitive). By their very nature, however, these processes are varied and differ between places, rooted in particular local-regional constellations of policy-making pressures, actor personalities and established ways of doing things. This paper examines such processes for two regions in eastern Germany, both with distinctly different economic traditions and geographical contexts, aiming to illustrate the multi-layered process of regionalisation and region making. Inevitably, within the scope of this paper, the study cannot cover all possible models and regionalisation approaches across eastern Germany, because they not only differ between places, but also over time.  相似文献   

18.
Social practice theories provide a unique platform for understanding how everyday practices become globalised through migration, spreading from one place to another, replacing local, often more sustainable, variations. Set in the context of the spreading of resource-intensive practices such as multiple daily showers, we explore the movement and migration of domestic practices, acknowledging that they are constantly shifting from one relatively stable form to another. Drawing on the phenomenon of human migration where, for various reasons, people move from one country to another, we argue that migrants ‘carry’ practices which can ‘travel’ between and across cultures, generations and living arrangements. People who migrate from one place to another are exposed to a greater range of practices than other more sedentary populations. On encountering new practices in the destination country, we propose the practices carried by migrants are subject to various forms of integration, disintegration and transferral across generations. Borrowing the idea of muscle memory from the biophysical sciences, we introduce ‘practice memory’ to explain how some practices thought to be ‘dead’ can be resurrected with relative ease. We also suggest that practice memory may explain how some practices can be performed in new contexts despite a person never having performed them before. We conclude by reflecting on how understanding these migratory processes, and the role of practice memory within them, offer new insights into how practices move and migrate from one time–space to another.  相似文献   

19.
Alluvial fans are relatively simple depositional systems, due to the direct coupling of sediment sources and adjacent accumulation areas. Nonetheless, general models of alluvial‐fan evolution and stratigraphy remain elusive, due to the great sensitivity of such systems to allogenic controls and their strongly case‐specific responses. Autogenic processes intrinsic to alluvial‐fan dynamics can complicate stratigraphic architectures, with effects not easily distinguishable from those of allogenic forcing. A distinction is made here between lateral autogenic dynamics, tied to spatial sediment distribution over fan surfaces, and vertical autogenic dynamics, related to independent incision‐aggradation cycles. Autogenic mechanisms have been highlighted recently by modelling studies, but remain poorly constrained in field‐based studies. Examples are presented here from the margins of the Cenozoic Teruel and Ebro basins (Spain), where alluvial fans accumulated thick successions during phases of basin topographic closure and endorheic drainage which promoted forced aggradation. Fan successions consist of conformable architectures of stacked clastic sheets, laterally continuous and with no evidence of internal unconformities, inset architectures, fan segmentation or preserved incised channels. Continuous aggradation in these closed basins strongly inhibited ‘vertical’ autogenic dynamics in the form of fan head and through fan incision, due to the forced rise in geomorphic base level and the creation of positive accommodation. Furthermore, the lack of incised channels favoured widespread sediment transport and aggradation over broad fan sectors in relatively short time spans, in contrast to the typical occurrence of active lobes and abandoned fan surfaces caused by ‘lateral’ autogenic dynamics. Stratigraphic records of alluvial fans developed in endorheic basins are essentially complete and largely unaffected by autogenic processes. The latter characteristic implies that they can be more unambiguously interpreted in terms of allogenic forcing, because stratigraphic signatures are not complicated by the effects of complex fan autodynamics.  相似文献   

20.
The S1 pedocomplex, correlated to Oxygen Isotope Stage 5 of the ocean cores, has been traced west of the Loess Plateau on to the extreme northeastern margin of the Qinghai-Xizang (Tibetan) Plateau in China. Detailed micromorphological analysis of closely spaced thinsections from the pedocomplex at this site provides the basis for reconstruction of the sequence of pedosedimentary processes and associated palaeoenvironmental changes occurring during this time interval. The six pedosedimentary stages identified are interpreted in terms of temporal variations in depositional rates, size of particles transported and availability of moisture for pedogenic alteration, as determined by changing balances in dominance of winter and summer monsoonal forces. Two main ‘soil-forming intervals’ are identified: the more extensive of the two in terms of resultant pedological features reflects pedogenic alteration at a relatively ‘stable’ land surface under a semi-arid climate during the later part of pedosedimentary stage 2. The other main period corresponds to pedosedimentary stages 4 and 5, when leaching and bioturbation processes were active at aggrading surfaces, leading to development of an accretionary unit without clear differentiation of horizons. Pedosedimentary stages 1, 3 and 6 were characterised mainly by rapid rates of coarse loess accumulation, with synsedimentary modification restricted to surface slaking and crust formation, and minor localised redistribution of calcite.  相似文献   

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