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1.
Robin Jane Roff   《Geoforum》2008,39(3):1423-1438
On August 31th, 2006 the California Senate shelved SB1056, a bill which would have granted the State jurisdiction over the regulation of seed and nursery stock. Ostensibly proposed to ensure “a level playing field” for agricultural and food producers, SB1056 is one of a host of legislation drafted across the United States to preempt county and municipal bans on genetically engineered crops. In California, the heated struggle around “preemption” exemplifies the interweaving of neoliberal ideology with industry attempts to prevent an unfavorable regulatory environment, but more importantly the contingencies and vulnerabilities of this strategy. After reviewing SB1056’s history, this paper examines how a diverse opposition movement capitalized on the friction between the neoliberal arguments mobilized by supporters and dominant Californian political philosophies. The paper then highlights the ultimate effect of SB1056 through a critical exploration of current state and federal regulation and the entrenched interests of the California government. I argue that more than simply opening new spaces for accumulation, SB1056 would have muted opposition voices and transferred power to institutions financially committed to the technology’s commercialization.  相似文献   

2.
Mary Beth Pudup   《Geoforum》2008,39(3):1228-1240
Since the 1980’s organized garden projects have proliferated in a institutional settings associated with the “roll-out” neoliberal state and the sad consequences of neoliberalism more generally: jails, schools, hospitals and other clinical settings for “at-risk” populations. This article advances the concept “organized garden project” over the richly connotative, but inchoate term “community garden,” and links the long episodic history of garden projects with changing discourses about the supposedly transformative power of gardening practice for individual and social transformation. The article highlights two organized garden projects within the San Francisco Bay area, a chief locus in the movement to using organized garden projects to produce new individual and collective subjectivities. The case studies assess, from the typically unambiguous standpoint of the garden organizers, the nature of the subjectivity that gardening practice is supposed to produce, the need for such alternative subjectivity and the “difference” such alternatives are believed to make for the individual and in the wider social, political and economic milieu.  相似文献   

3.
Prytherch  David L.  Huntoon  Laura 《GeoJournal》2005,62(1-2):41-50
European politics and planning have recently been characterized by a shift to economic entrepreneurialism at sub-national scales, and the planned redevelopment of the city-region in pursuit of global competitiveness, which scholars have interpreted in light of political-economic “rescaling” or regionalization and the emergence of a “new regionalism.” Analyzing rescaling largely in terms of shifting economic and institutional structures, however, many accounts underestimate the complexity and enduring power of so-called ‘old’ regionalist politics of culture and identity as backdrop to urban redevelopment planning. In this paper we address how the urban planning process mediates between the seemingly dichotomous tendencies of regionalized entrepreneurialism and cultural regionalism. Using case studies of two Spanish autonomous regions and their major urban centers – the Basque Country or Euskadi (Bilbao) and the Comunitat Valenciana (València) – we review the historical geography of planning in the European region in order to explore how cultural regionalism collides with economic rescaling and entrepreneurialism, in and through the planned landscape. We propose that such emerging and hybrid politics and planning be understood as a form of entrepreneurial regionalism, a culturally inflected form of economic competitiveness characteristic of but not unique to the Spanish region. This specific notion of entrepreneurial regionalism may illuminate how planners mediate global and local imperatives within political discourse and landscapes that materialize them, and allow us to better reconceptualize the relationship between economic globalization, state restructuring, and cultural politics in a new Europe of the Regions.  相似文献   

4.
European politics and planning have recently been characterized by a shift to economic entrepreneurialism at sub-national scales, and the planned redevelopment of the city-region in pursuit of global competitiveness, which scholars have interpreted in light of political-economic “rescaling” or regionalization and the emergence of a “new regionalism.” Analyzing rescaling largely in terms of shifting economic and institutional structures, however, many accounts underestimate the complexity and enduring power of so-called ‘old’ regionalist politics of culture and identity as backdrop to urban redevelopment planning. In this paper we address how the urban planning process mediates between the seemingly dichotomous tendencies of regionalized entrepreneurialism and cultural regionalism. Using case studies of two Spanish autonomous regions and their major urban centers – the Basque Country or Euskadi (Bilbao) and the Comunitat Valenciana (València) – we review the historical geography of planning in the European region in order to explore how cultural regionalism collides with economic rescaling and entrepreneurialism, in and through the planned landscape. We propose that such emerging and hybrid politics and planning be understood as a form of entrepreneurial regionalism, a culturally inflected form of economic competitiveness characteristic of but not unique to the Spanish region. This specific notion of entrepreneurial regionalism may illuminate how planners mediate global and local imperatives within political discourse and landscapes that materialize them, and allow us to better reconceptualize the relationship between economic globalization, state restructuring, and cultural politics in a new Europe of the Regions.  相似文献   

5.
In this paper, I analyze the connections made between women and water in a Rajasthani drinking water supply project as a significant part of drinking water’s commodification. For development policy makers, water progressing from something free to something valued by price is inevitable when moving economies toward modernity and development. My findings indicate that water is not commodified simply by charging money for it, but through a series of discourses and acts that link it to other “modern” objects and give it value. One of these objects is “women”. I argue that through women’s participation activities that link gender and modernity to new responsibilities and increased mobility for village women involving the clean water supply, a “traditional” Rajasthani woman becomes “modern”. Water, in parallel, becomes “new”, “improved” and worth paying for. Women and water resources are further connected through project staff’s efforts to promote latrines by targeting women as their primary users. The research shows that villagers applied their own meanings to latrines, some of which precluded women using them. This paper fills a gap in feminist political ecology, which often overlooks how gender is created through natural resource interventions, by concerning itself with how new meanings of “water” and “women” are mutually constructed through struggles over water use and its commodification. It contributes to critical development geography literatures by demonstrating that women’s participation approaches to natural resource development act as both constraints and opportunities for village constituents. It examines an under-explored area of gender and water research by tracing village-level struggles over meanings of latrines.  相似文献   

6.
John Harrison   《Geoforum》2006,37(6):932-943
The “region” and “regional change” have been elusive ideas within political and economic geography, and in essence require a greater understanding of their dynamic characteristics. Trailing in the backwaters of the devolution to the Celtic nations of Britain, the contemporary era of New Labour’s political-economic ideology, manifest through “third-way” governance in England places the region and its functional capacity into the heart of geographical inquiry. Drawing upon a new regionalist epistemology, this paper seeks to recover a sense of (regional) political economy through a critical investigation of the development and formulation of Blair’s “New Regional Policy” (NRP). I address how New Labour has attempted to marry economic regionalisation on the one hand, and democratic regionalism on the other. This paper specifically questions the wisdom of such a marriage of politically distinct ideologies through a critical investigation of the underlying contradictions of their strategy from both a theoretical and empirical standpoint. Demonstrated both in the North East “no” vote in 2004, and in the post-mortem undertaken by the ODPM Select Committee in 2005, the paper illustrates how a loss of political drive gradually undermined the capacity of devolution to deliver in England. Finally, I argue that through the lens of the NRP we can speculate on some of the wider issues and implications for the study of regional governance.  相似文献   

7.
Deposits of the “porphyry” family (essentially porphyry copper and gold-porphyry copper, gold-bearing porphyry molybdenum-copper, gold-containing porphyry copper-molybdenum and porphyry molybdenum deposits) are associated in time and space with granitoid magmatism mainly in Phaerozoic volcano-plutonic belts. Whatever their age, the deposits belong to two types of belts: basaltic belts, representing axial zones of island arcs, or andesitic belts formed within active continental (Andean-type) margins.The petrochemistry of ore-bearing magmatism related to the nature of the substratum of volcano-plutonic belts, reveals a number of essential characteristics, both in composition and zonation of wallrock alteration and ore mineralization. These characterisics enabled previous researchers to establish four models of porphyry copper deposits based on their lithologic associations, e.g., “diorite”, “granodiorite”, “monzonite” and “granite”.Pophyry copper deposits are thought to be the product of self-generating “two-fluid mixing” ore-magmatic systems. Porphyry intrusions are pathways for energy and metals from deep-seated magma chambers, of which the upper mineralized parts are accessible for observation. The relationship between magmatic fluids and meteoric water participating in the ore-forming processes (dependent on the structural-petrophysical conditions of formation), provide a subdivision for the porphyry copper ore-magmatic systems into three types: “open”, “closed” and “transitional”.Concurrently, a common trend in the evolution of the systems has been established, from a nearly autoclave regime of structural-and ore-forming processes to a gradual increase in the importance of hydrothermal recycling. The completeness of the OMS (ore-magmatic system) development according to this scheme, which determines the existence of various OMS types, depends on many factors, the most important being the depth of formation of porphyry intrusive bodies, the petrophysical peculiarities of the host rocks and the palaeohydrogeological conditions of ore deposition.Although rock fracturing (especially defluidization: second boiling) and contraction are caused by the same mechanisms, the stockwork growth in “open” and “closed” systems, relative to the wall rock, takes place in opposite directions, primarily due to different petrophysical parameters of the near-stock environment.In “open” systems structural and ore metasomatic processes are finalized. Fractures extend progressively from porhyry stocks into the marginal parts of the intrusive framework and extension of large-scale recycling of magmatic and activated meteoric water, in the same direction, result in the formation of ore-bearing stockworks. These are large in all dimensions, cover mainly hanging-wall zones and are characterized by clearly defined concentric mineral zoning and extensive geochemical haloes.In a “closed” OMS with centripetal growing fractures, hydrothermal convection is stunted. The vertical extension of recycling cells is restricted and the volume of meteoric water involved in circulation during the period of ore deposition is relatively small. As a result, relatively small intra-intrusive lenticular stockworks are developed which are characterized by close co-existence of several generations of mineralization with fragmentary preservation of the earliest ones. These are characterized by the elements of “reverse” zoning, increased density of the veinlets and metal content, as well as poorly developed hanging-wall dispersion haloes.  相似文献   

8.
Soils can possess heritage characteristics and can be classified according to their “cultural value”. “Pedosites”, likewise “geosites”, are important for science and teaching, for tourism and recreation, provide elements in the Environmental Impact Analysis, and enhance the awareness of population towards the value of the land where they live. Pedosite richness and diversity are a resource of a territory that should be evaluated and considered in land planning. The methodology used to evaluate and group pedosites of Italy, and the software developed to collect such information and create a specific geodatabase, are presented in this paper as an example for use in other countries. An Italian geodatabase storing 726 pedosites was created. Soil profiles as cultural heritage were: (i) palaeosols, (ii) soils from archaeological and palaeontological sites, (iii) soils displaying natural or anthropic processes and benchmarks of classifications. Pedosites as soilscapes were: (i) cultural landscapes; (ii) soilscapes determining the amenity of a panorama; (iii) soilscapes in fragile environmental balance; (iv) soilscapes that contribute to the outliving of particular ecosystems. The criteria for the evaluation of pedosites and the suggestions for their protection were indicated as follows: (i) area and (ii) type of scientific interest, (iii) state of conservation, (iv) type and (v) intensity of risk, (vi) level of knowledge, (vii) geological age, (viii) protection and (ix) proposed protection, (x) accessibility, (xi) visibility, (xii) exposure, (xiii) observability. The geodatabase can be used at different scales. Two maps, at national and local levels, exemplify the methodology and show how to use the geodatabase for didactic purposes or the creation of integrated Geoparks. Pedosite indices of diversity highlight the greater pedosite variety in the soil regions of Mediterranean Italy.  相似文献   

9.
Jody Emel  Matthew T. Huber   《Geoforum》2008,39(3):1393-1407
Natural resource investment in the mining sector is often mediated through conflicts over rent distribution between corporate capital and landowner states. Recent rounds of neoliberal policy promoted by the World Bank have highlighted the need for landowner states to offer incentives in order to attract “high risk” capital investment. In Sub-Saharan Africa, in particular, countries have been pushed to offer attractive fiscal terms to capital, thereby lowering the proportion traditionally called rent. This paper examines how the concept of “risk” has been mobilized to legitimate such skewed distributional arrangements. While certain conceptions of social and ecological “risk” have been prevalent in political and social theoretic discourse on mining, such focus elides the overwhelming contemporary power of our notion of “neoliberal risk” – or the financial/market risks – in actually setting the distributional terms of mineral investment. We illustrate our argument by examining the nexus of World Bank mining policy promotion and Tanzanian policy in the late 1990s meant to attract foreign direct investment in gold production. In closing, we suggest that just as “risk” is used to legitimate attractive fiscal terms for investment, recent events highlight how skewed distribution of benefits may set into motion risks that corporate capital had not bargained for.  相似文献   

10.
11.
This paper discusses the occurrence of 28,30-dinor-17α,18α,21β-hopane (bisnorhopane) in stratigraphically, fairly well preserved Viking Group sections from wells in local depressions in the North Viking Graben Area. The results show the presence of high relative amounts of bisnorhopane in the “Syn-rift sections”, whilst the “Post-rift sections” contain little or no bisnorhopane. Since most exploration wells are drilled on structural highs, primarily penetrating the “Post-rift Draupne”, this may explain why many analyzed source rock sections in this area contain little bisnorhopane.As a correlation of Draupne sections using the vertical, relative bisnorhopane distributions, it is suggested to be a potential stratigraphic marker for the area, indicating the presence of “Syn-rift Draupne” sediments.The relative bisnorhopane amounts follow a logarithmic reduction with depth and thermal maturity. The bisnorhopane signal is nearly extinguished at 3700 m depth at a maturity of Ro = 0.9–1.0%.  相似文献   

12.
The offsets on the ocean floor, usually called “transform-faults” are not shear faults common in solid Hookian rocks, but reflect the viscous Newtonian properties of laminar flow at the time when the upwelling magma along the spreading center was still in a liquid state. During spreading this liquid is carried away with the walls of the spreading center. This movement creates a pattern of stream lines in the liquid which run parallel to the direction of spreading. “Transform faults” are initiated along zones where a larger rate of shear disturbs the process of solidification. Consequently the strength of the basalt after solidification will be impaired along these zones. These weak zones will fracture under the thermo-elastic stresses during the final stage of cooling.The history of the term “transform fault” is discussed and the name “spreading offset” is proposed.  相似文献   

13.
J. -B. Edel   《Tectonophysics》2003,363(3-4):225-241
Generally, the lack of bedding criteria in basement units hampers the interpretation of paleomagnetic results in terms of geotectonics. Nevertheless, this work demonstrates that successive remagnetizations recorded in Early Carboniferous metamorphic and plutonic units, without clear bedding criteria, can be used to constrain a polyphased tectonic evolution consisting of a regional clockwise rotation, followed by a folding phase, a tilting phase and a second regional clockwise rotation.Metamorphic, ultrabasic, tonalitic and granitic rocks from different parts of Limousin (western French Massif central; 45.5°N/1.25°E), which underwent metamorphism during Devonian–Early Carboniferous or were intruded in the Early–Middle Carboniferous, were sampled in order (a) to identify the magnetic overprinting phases and the related tectono-magmatic events and (b) to constrain the regional and plate tectonic evolution of Limousin. Paleomagnetic results from 32 new and 26 sites investigated previously show that at least 90% of the magnetization isolated in rocks older than 330 Ma are overprints. In agreement with results from adjacent areas of the Variscan belt, the major overprinting phases occurred: (a) in the last stages of the major exhumation phase [332–328 Ma; mean Virtual Geomagnetic Pole (VGP) “Cp”: 37°N/70.5°E], (b) during the post-collisional syn-orogenic extension (325–315 Ma; VGP “B”: 11°N/114°E), (c) in the Latest Carboniferous and Early Permian (VGP “A1”: 27°N/149°E) and (d) in the Late Permian (VGP “A”: 48°N/146°E). The Middle–Late Carboniferous overprints “Cp” and “B” are contemporaneous with emplacement of leucogranitic, crustal derived plutons, and probably result from the hydro-thermal activity related to the magmatism. The drift from “Cp” directions to “B” directions implies that after 330 Ma, Limousin underwent a clockwise rotation by 65°, together with the Central Europe Variscides. The “Bt” components, the VGPs of which deviate from the mean apparent polar wander path (APWP) of the belt, are interpreted as “B” overprints tilted during Late Variscan tectonics, that is, in the time range 325–315 Ma. The first and most important generation of “Bt” overprints was tilted during NW–SE folding associated with NE–SW shortening, updoming and emplacement of leucogranitic plutons. The second generation reveals southeastward tilting due to NE-striking normal faulting. The drift from “B” to “A1” directions implies that Limousin has participated to the second clockwise rotation by 40° of the whole belt in Westphalian times.  相似文献   

14.
Three samples of gem quality plagioclase crystals of An60 were experimentally deformed at 900 °C, 1 GPa confining pressure and strain rates of 7.5–8.7×10−7 s−1. The starting material is effectively dislocation-free so that all observed defects were introduced during the experiments. Two samples were shortened normal to one of the principal slip planes (010), corresponding to a “hard” orientation, and one sample was deformed with a Schmid factor of 0.45 for the principal slip system [001](010), corresponding to a “soft” orientation. Several slip systems were activated in the “soft” sample: dislocations of the [001](010) and 110(001) system are about equally abundant, whereas 110{111} and [101] in ( 31) to ( 42) are less common. In the “soft” sample plastic deformation is pervasive and deformation bands are abundant. In the “hard” samples the plastic deformation is concentrated in rims along the sample boundaries. Deformation bands and shear fractures are common. Twinning occurs in close association with fracturing, and the processes are clearly interrelated. Glissile dislocations of all observed slip systems are associated with fractures and deformation bands indicating that deformation bands and fractures are important sites of dislocation generation. Grain boundaries of tiny, defect-free grains in healed fracture zones have migrated subsequent to fracturing. These grains represent former fragments of the fracture process and may act as nuclei for new grains during dynamic recrystallization. Nucleation via small fragments can explain a non-host-controlled orientation of recrystallized grains in plagioclase and possibly in other silicate materials which have been plastically deformed near the semi-brittle to plastic transition.  相似文献   

15.
July temperatures for the past 6000 yr at 11 sites in northern Canada have been predicted by transfer-function equations. Normalized departures from the mean of each time series at 250-yr intervals are analyzed by principal component (eigenvector) analysis. An initial analysis included 9 sites and the first three principal components accounted for 85.7% of the variance. Maps of the loadings on the principal components show broad spatial coherence on all three components. Temporal coefficients (principal component scores) illustrate major regional and local midsummer temperature variations. An additional 2 sites were then included but the spatial pattern of the loadings remained essentially unchanged. A further test of this approach, with a view toward predicting paleoclimates of northern regions, was to use the spatial coefficients (loadings) to estimate the July temperature departures at an “unknown” site (Long Lake, Keewatin). This reconstruction compares favorably with an independent transfer-function reconstruction (Kay, 1979). Power spectrum analysis of the significant principal component scores (temperature departures) over the 6000 yr showed that the temporal fluctuations associated with the first three principal components follow a “red noise” spectrum, indicative of strong persistence in the reconstructed climatic records. The scores on the fourth principal component approximate a “white noise” spectrum. A peak in power between 2000 and 3000 yr occurs in the variance spectrum of the second principal component (significance 10%). We conclude that eigenvector analysis of Holocene paleoclimatic data has considerable power and may be useful for identifying regional and local climatic variations.  相似文献   

16.
The Cenomanian/Turonian Boundary Event (CTBE) at Wunstorf, north-west Germany, has been analysed palynologically by high resolution sampling to reconstruct changes in relative sea-level and water mass character within photic zone waters. Based on changes in the ratio of terrigenous sporomorphs to marine palynomorphs (t/m index), the distribution of the organic-walled algal taxa as well as of selected dinocyst taxa and groups the section can largely be subdivided into pre-“plenus-bed” and post-“plenus-bed” intervals, reflecting different stages of third-order relative sea-level cycles and/or changes in water mass influence in the photic zone. Accordingly, the pre-“plenus-bed” interval is placed in a transgressive systems tract starting at the “facies change” event (C. guerangeri/M. geslinianum ammonite Zone boundary) with the maximum flooding surface at the top of the “Chondrites II” bed (top of R. cushmani Biozone). A highstand systems tract is suggested from the base of the “plenus-bed” up the base of the “fish-shale” event. Within the “fish-shale” event interval, a transgressive systems tract is suggested to start at the base of the thin, grey-green marly interbed. The Cenomanian/Turonian boundary proper, as defined by the first occurrence of Mytiloides spp., as well as the lowermost Turonian are located within the initial phase of a transgressive systems tract. With respect to water mass characteristics within photic-zone waters, the pre-“plenus-bed” interval is predominantly characterized by warm water masses that changed gradually towards the deposition of the “Chondrites II” bed, where a strong influence of cool and/or salinity-reduced waters is indicated by various palynological proxies. Within the post-“plenus-bed” interval a mixture and/or alternation of warmer and cooler waters is indicated, with the warmer water influence increasing gradually towards and within the Lower Turonian stage. The increased proportions of prasinophytes within the “Chondrites II” bed and parts of the “fish-shale” interval may indicate availability of reduced nitrogen chemospecies, especially ammonium, within photic-zone waters as a function of a vertical expansion of the oceanic O2-minimum zone.  相似文献   

17.
Leping coal is known for its high content of “barkinite”, which is a unique liptinite maceral apparently found only in the Late Permian coals of South China. “Barkinite” has previously identified as suberinite, but on the basis of further investigations, most coal petrologists conclude that “barkinite” is not suberinite, but a distinct maceral. The term “barkinite” was introduced by (State Bureau of Technical Supervision of the People's Republic of China, 1991, GB 12937-91 (in Chinese)), but it has not been recognized by ICCP and has not been accepted internationally.In this paper, elemental analyses (EA), pyrolysis-gas chromatography, Rock-Eval pyrolysis and optical techniques were used to study the optical features and the hydrocarbon-generating model of “barkinite”. The results show that “barkinite” with imbricate structure usually occurs in single or multiple layers or in a circular form, and no definite border exists between the cell walls and fillings, but there exist clear aperture among the cells.“Barkinite” is characterized by fluorescing in relatively high rank coals. At low maturity of 0.60–0.80%Ro, “barkinite” shows strong bright orange–yellow fluorescence, and the fluorescent colors of different cells are inhomogeneous in one sample. As vitrinite reflectance increases up to 0.90%Ro, “barkinite” also displays strong yellow or yellow–brown fluorescence; and most of “barkinite” lose fluorescence at the maturity of 1.20–1.30%Ro. However, most of suberinite types lose fluorescence at a vitrinite reflectance of 0.50% Ro, or at the stage of high volatile C bituminous coal. In particular, the cell walls of “barkinite” usually show red color, whereas the cell fillings show yellow color under transmitted light. This character is contrary to suberinite.“Barkinite” is also characterized by late generation of large amounts of liquid oil, which is different from the early generation of large amounts of liquid hydrocarbon. In addition, “barkinite” with high hydrocarbon generation potential, high elemental hydrogen, and low carbon content. The pyrolysis products of “barkinite” are dominated by aliphatic compounds, followed by low molecular-weight aromatic compounds (benzene, toluene, xylene and naphthalene), and a few isoprenoids. The pyrolysis hydrocarbons of “barkinite” are mostly composed of light oil (C6–C14) and wet gas (C2–C5), and that heavy oil (C15+) and methane (C1) are the minor hydrocarbon.In addition, suberinite is defined only as suberinized cell walls—it does not include the cell fillings, and the cell lumens were empty or filled by corpocollinites, which do not show any fluorescence. Whereas, “barkinite” not only includes the cell walls, but also includes the cell fillings, and the cell fillings show bright yellow fluorescence.Since the optical features and the hydrocarbon-generating model of “barkinite” are quite different from suberinite. We suggest that “barkinite” is a new type of maceral.  相似文献   

18.
Forearc areas (“non-volcanic” arcs) of contemporary island arcs at convergent plate boundaries contain magmatic rocks. Geological evidence, seismic profiles, heat flow data, density considerations and petrological and geochemical arguments suggest that a forearc tholeiitic association (FAT) (containing high-Mg calc-alkaline andesites) is present in “non-volcanic” arcs at some stage of island-arc development. The fractionated, as well as primitive magma, is unable to penetrate low-density sediments and underplates thick piles of unconsolidated accreting rocks. The underplating causes upwelling. The occurrence of magma in forearcs provides an alternative interpretation for the tectonic setting of some ophiolitic masses. Rather than “ocean-ridge formation” and later “obduction” it offers an autochthonous (island-arc bound and geologically-substantiated) interpretation for the ophiolite suite.  相似文献   

19.
Ryan E. Galt   《Geoforum》2008,39(3):1378-1392
The environmental impact of agro-export production in developing countries remains an important research topic. The political economy-inspired literature on developing country agro-exports maintains that export crops are pesticide intensive – or, more generally, environmentally destructive – while local and national market crops are less pesticide intensive, or environmentally benign. If used to draw conclusions about the impact of national market versus export market expansion, this view has significant limitations, most importantly the comparison of high-commodity value export crops with low-commodity value crops for national market. To overcome this and other limitations of prior analyses, this paper addresses the question: how does market orientation influence pesticide intensity where the same crops are grown for both the national market and for export? Data from a survey of Costa Rican vegetable farmers are used to compare pesticide intensity of 27 vegetable crops, five of which are produced for both national and export markets. The general pattern that emerges is that national market vegetables are more pesticide intensive than export vegetables in the area. Yet, controlling more for the crop variable is important, and specific comparisons of the five vegetables grown for both markets – carrot, chayote, corn, green beans, and squash – illustrate that market orientation alone does not determine pesticide intensity, but that it is jointly influenced by regulatory risk, crop value, and pest susceptibility, among other factors. Continued attention to both political economy and ecological processes in “second nature” will allow political ecology to make important contributions to understanding pesticide problems and implementing agroecological solutions.  相似文献   

20.
The seismically most important region of Romania is the Vrancea epicentral area of the Eastern Carpathians Arc Bend (ECAB). The occurrence of earthquakes is here indisputably caused by subduction processes, either relict ones in connection with a “dead” slab, or directly produced by continuous underthrusting or by type A subduction, after a continent/continent collision.In order to investigate the type of subduction process, the authors used structural geological criteria i.e., features of local strike-slip faults and sigmoidal curves of fold axes or of overthrusting lines, already mapped across the area.By use of these criteria, it is concluded that there is an offset directed northwestwards, with an amplitude of 9–12 km, within the Cretaceous-Paleogene flysch and Neogene molasse deposits outcropping at ECAB.If the measured transcurrent movements reflected only the distortions of the sedimentary cover, the offset should be directed SE, because overthrusting processes are larger from SW to NE at ECAB. Instead, the northwestern direction disclosed by the offset vector suggests that the basement movement occurred when the formations were transversally dislocated, after the “charriage” structure at ECAB had been born.This conclusion is consistent with a hypothetical NW movement of the basement of the ECAB foreland.  相似文献   

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