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Contemporary Processes (contemporary + process)
Selected AbstractsDisturbance and reef topography maintain high local diversity in Ecklonia radiata kelp forestsOIKOS, Issue 10 2007Benjamin D. Toohey Disturbance of competitive-dominant plant and algae canopies often lead to increased diversity of the assemblage. Kelp forests, particularly those of temperate Western Australia, are habitats with high alpha diversity. This study investigated the roles of broad-scale canopy loss and local scale reef topography on structuring the kelp-dominated macroalgal forests in Western Australia. Eighteen 314,m2 circular areas were cleared of their Ecklonia radiata canopy and eighteen controls were established across three locations. The patterns of macroalgal recolonisation in replicate clearances were observed over a 34,month period. Macroalgal species richness initially increased after canopy removal with a turf of filamentous and foliose macroalgae dominating cleared areas for up to seven months. A dense Sargassum canopy dominated cleared areas from 11 to 22,months. By 34,months, partial recovery of the kelp canopy into cleared areas had occurred. Some cleared areas did not follow this trajectory but remained dominated by turfing, foliose and filamentous algae. As kelp canopies developed, the initial high species diversity declined but still remained elevated relative to undisturbed controls, even after 34 months. More complex reef topography was associated with greater variability in the algal assemblage between replicate quadrats suggesting colonising algae had a greater choice of microhabitats available to them on topographically complex reefs. Shading by canopies of either Sargassum spp. and E. radiata are proposed to highly influence the abundance of algae through competitive exclusion that is relaxed by disturbance of the canopy. Disturbance of the canopy in E. radiata kelp forests created a mosaic of different patch types (turf, Sargassum -dominated, kelp-dominated). These patch types were both transient and stable over the 34 months of this study, and are a potential contemporary process that maintains high species diversity in temperate kelp-dominated reefs. [source] Defining and Contesting Environmental Justice: Socio-natures and the Politics of Scale in the DeltaANTIPODE, Issue 4 2009Julie Sze Abstract:, This article examines a contemporary process intended to "identify a strategy for managing the Sacramento,San Joaquin Delta as a sustainable ecosystem that would continue to support environmental and economic functions that are critical to the people of California" (Delta Vision 2008, http://deltavision.ca.gov/AboutDeltaVision.shtml). Environmental injustices in the Delta are exacerbated by connected conflicts between knowledge and power, over the scale at which "environmental justice" and the "Delta" are understood through public policy. The rejection of environmental justice and the socio-natural in the Delta Vision process represents how contemporary policy processes are recreating and reenacting the power/knowledge dynamics that have defined the Delta, placed it on a path to ecological collapse and injected high levels of social and racial injustice in its landscape over the past 150 years. Our article combines an ethnographic and a historical geographical approach that contributes to the literature on environmental justice and scale and links with the literature on water governance and power to advance the task of defining environmental justice from the academic and policy perspectives. [source] Variegated neoliberalization: geographies, modalities, pathwaysGLOBAL NETWORKS, Issue 2 2010NEIL BRENNER Abstract Across the broad field of heterodox political economy, ,neoliberalism' appears to have become a rascal concept , promiscuously pervasive, yet inconsistently defined, empirically imprecise and frequently contested. Controversies regarding its precise meaning are more than merely semantic. They generally flow from underlying disagreements regarding the sources, expressions and implications of contemporary regulatory transformations. In this article, we consider the handling of ,neoliberalism' within three influential strands of heterodox political economy , the varieties of capitalism approach; historical materialist international political economy; and governmentality approaches. While each of these research traditions sheds light on contemporary processes of market-oriented regulatory restructuring, we argue that each also underplays and/or misreads the systemically uneven, or ,variegated', character of these processes. Enabled by a critical interrogation of how each approach interprets the geographies, modalities and pathways of neoliberalization processes, we argue that the problematic of variegation must be central to any adequate account of marketized forms of regulatory restructuring and their alternatives under post-1970s capitalism. Our approach emphasizes the cumulative impacts of successive ,waves' of neoliberalization upon uneven institutional landscapes, in particular: (a) their establishment of interconnected, mutually recursive policy relays within an increasingly transnational field of market-oriented regulatory transfer; and (b) their infiltration and reworking of the geoinstitutional frameworks, or ,rule regimes', within which regulatory experimentation unfolds. This mode of analysis has significant implications for interpreting the current global economic crisis. [source] The future of urban sociology: report of joint sessions of the British and American Sociological AssociationsINTERNATIONAL JOURNAL OF URBAN AND REGIONAL RESEARCH, Issue 4 2002Beth Perry This article reports on two joint sessions of the British and American Sociological Associations held during the course of 2001 as a first step toward more structured dialogue and debate between the two national associations. Drawing on the comments of a number of leading academics on both sides of the Atlantic, this paper presents a series of discussions about the role and future of urban sociology. It explores the challenges and opportunities offered to urban sociology by increasing interdisciplinarity and multidisciplinarity in the field of urban studies as a whole. It then explores the role of sociology in understanding the relationship between contemporary processes of globalization and urban change and the degree to which this constitutes a new dynamic core of sociological theory and research. The paper reveals that there are a variety of alternative futures for urban sociology and there would appear to be little agreement on one specific route, nor on how to get there. Urban sociology continues to face a variety of challenges and more debate on its future trajectory is clearly needed but it remains a vital and expanding sub,field. Cet article rend compte de deux sessions communes des associations de sociologie britannique et américaine qui ont eu lieu en 2001, premier stade vers un dialogue et un débat plus structurés entre les deux organismes nationaux. Partant des remarques d'un certain nombre de grands intellectuels des deux côtés de l'Atlantique, ce travail présente plusieurs discussions sur le rôle et l'avenir de la sociologie urbaine. Il examine les défis et possibilités que lui offrent l'interdisciplinarité et la pluridisciplinarité croissantes dans l'ensemble du domaine des études urbaines. Il explore ensuite comment la sociologie aide à comprendre la relation entre les processus contemporains de mondialisation et de changement urbain, et la mesure où peut ainsi émerger une nouvelle dynamique nodale pour la théorie et la recherche sociologiques. L'article expose plusieurs avenirs possibles de la sociologie urbaine, sans qu'il y ait apparemment d'accord sur une voie particulière ni sur le moyen d'y parvenir. La sociologie urbaine rencontre toujours de multiples défis et il faut manifestement approfondir les débats sur sa future trajectoire, mais elle demeure un sous,domaine à la fois crucial et en expansion. [source] Migrants, Settlers and Colonists: The Biopolitics of Displaced BodiesINTERNATIONAL MIGRATION, Issue 5 2008Cristiana Bastos All through the nineteenth century, Madeirans migrated from their Atlantic island to places as remote as Hawaii, California, Guyana and, later, South Africa. Scarcity of land, a rigid social structure, periodic famines and rampant poverty made many embark to uncertain destinies and endure the harsh labour conditions of sugarcane plantations. In the 1880s, a few hundred Madeirans engaged in a different venture: an experience of "engineered migration" sponsored by the Portuguese government to colonize the southern Angola plateau. White settlements, together with military control, scientific surveys and expeditions, contributed to strengthen the claims of European nations over specific territories in Africa. At that time, the long lasting claims of Portugal over African territories were not matched by sponsored colonial settlements or precise geographic knowledge about the claimed lands. There was little else representing Portugal than the leftover structures of the slave trade, the penal colonies and the free-lance merchants that ventured inland. In fear of losing land to the neighbouring German, Boer and British groups in south-western Africa, the Portuguese government tried then to promote white settlements by attracting farmers from the mainland into the southern plateau of Angola. As very few responded to the call, the settlement consisted mostly of Madeiran islanders, who were eager to migrate anywhere and took the adventure of Angola as just another destiny out of the island where they could not make a living. Their bodies and actions in the new place became highly surveilled by the medical delegates in charge of assessing their adaptation. The reports document what were then the idealized biopolitics of migration and colonization, interweaving biomedical knowledge and political power over displaced bodies and colonized land. At the same time, those records document the frustrations of the administration about the difficulties of the settlement experience and the ways in which colonial delegates blamed their failure on the very subjects who enacted and suffered through it. The eugenicism and racialism that pervade those writings, a currency during the age of empire, may now be out of taste both in science and in politics; however, they are not fully out of sight, and the subtle entrance of social prejudice into the hard concepts of biomedical science is still with us. Learning from this example may help analysing contemporary processes of medicalizing diversity or pathologizing the mobile populations, or, in other words, the biopolitics of migration in the 21st century. [source] Effects of habitat history and extinction selectivity on species-richness patterns of an island land snail faunaJOURNAL OF BIOGEOGRAPHY, Issue 10 2009Satoshi Chiba Abstract Aim, Local-scale diversity patterns are not necessarily regulated by contemporary processes, but may be the result of historical events such as habitat changes and selective extinctions that occurred in the past. We test this hypothesis by examining species-richness patterns of the land snail fauna on an oceanic island where forest was once destroyed but subsequently recovered. Location, Hahajima Island of the Ogasawara Islands in the western Pacific. Methods, Species richness of land snails was examined in 217 0.25 × 0.25 km squares during 1990,91 and 2005,07. Associations of species richness with elevation, current habitat quality (proportion of habitat composed of indigenous trees and uncultivated areas), number of alien snail species, and proportion of forest loss before 1945 in each area were examined using a randomization test and simultaneous autoregressive (SAR) models. Extinctions in each area and on the entire island were detected by comparing 2005,07 records with 1990,91 records and previously published records from surveys in 1987,91 and 1901,07. The association of species extinction with snail ecotype and the above environmental factors was examined using a spatial generalized linear mixed model (GLMM). Results, The level of habitat loss before 1945 explained the greatest proportion of variation in the geographical patterns of species richness. Current species richness was positively correlated with elevation in the arboreal species, whereas it was negatively correlated with elevation in the ground-dwelling species. However, no or a positive correlation was found between elevation and richness of the ground-dwelling species in 1987,91. The change of the association with elevation in the ground-dwelling species was caused by greater recent extinction at higher elevation, possibly as a result of predation by malacophagous flatworms. In contrast, very minor extinction levels have occurred in arboreal species since 1987,91, and their original patterns have remained unaltered, mainly because flatworms do not climb trees. Main conclusions, The species-richness patterns of the land snails on Hahajima Island are mosaics shaped by extinction resulting from habitat loss more than 60 years ago, recent selective extinction, and original faunal patterns. The effects of habitat destruction have remained long after habitat recovery. Different factors have operated during different periods and at different time-scales. These findings suggest that historical processes should be taken into account when considering local-scale diversity patterns. [source] Geological barriers and restricted gene flow in the holarctic skipper Hesperia comma (Hesperiidae)MOLECULAR ECOLOGY, Issue 11 2004M. L. FORISTER Abstract Patterns of genetic variation within a species may be a consequence of historical factors, such as past fragmentation, as well as current barriers to gene flow. Using sequence data from the mitochondrial cytochrome oxidase subunit II region (COII) and the nuclear gene wingless, we conducted a phylogeographical study of the holarctic skipper Hesperia comma to elucidate patterns of genetic diversity and to infer historical and contemporary processes maintaining genetic variation. One hundred and fifty-one individuals were sampled from throughout North America and Eurasia, focusing on California and adjacent regions in the western United States where morphological diversity is highest compared to the rest of the range. Analyses of sequence data obtained from both genes revealed a well-supported division between the Old and New World. Within western North America, wingless shows little geographical structure, while a hierarchical analysis of genetic diversity of COII sequences indicates three major clades: a western clade in Oregon and Northern California, an eastern clade including the Great Basin, Rocky Mountains and British Columbia, and a third clade in southern California. The Sierra Nevada and the Transverse Ranges appear to be the major barriers to gene flow for H. comma in the western United States. Relatively reduced haplotype diversity in Eurasia compared to North America suggests that populations on the two continents have been affected by different historical processes. [source] Genetic variation within and among fragmented populations of lesser prairie-chickens (Tympanuchus pallidicinctus)MOLECULAR ECOLOGY, Issue 3 2003Ronald A. Van Den Bussche Abstract As a result of recurrent droughts and anthropogenic factors, the range of the lesser prairie-chicken (Tympanuchus pallidicinctus) has contracted by 92% and the population has been reduced by approximately 97% in the past century, resulting in the smallest population size and most restricted geographical distribution of any North American grouse. We examined genetic variation through DNA sequence analysis of 478 base pairs of the mitochondrial genome and by assaying allelic variation at five microsatellite loci from lesser prairie-chickens collected on 20 leks in western Oklahoma and east-central New Mexico. Traditional population genetic analyses indicate that lesser prairie-chickens maintain high levels of genetic variation at both nuclear and mitochondrial loci. Although some genetic structuring among lesser prairie-chicken leks was detected within Oklahoma and New Mexico for both nuclear and mitochondrial loci, high levels of differentiation were detected between Oklahoma and New Mexico populations. Nested-clade analysis of mitochondrial haplotypes revealed that both historic and contemporary processes have influenced patterns of haplotype distributions and that historic processes have most likely led to the level of differentiation found between the Oklahoma and New Mexico populations. [source] | |||||||||||||