956 resultados para non-native macrophytes


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The exponential growth of studies on the biological response to ocean acidification over the last few decades has generated a large amount of data. To facilitate data comparison, a data compilation hosted at the data publisher PANGAEA was initiated in 2008 and is updated on a regular basis (doi:10.1594/PANGAEA.149999). By January 2015, a total of 581 data sets (over 4 000 000 data points) from 539 papers had been archived. Here we present the developments of this data compilation five years since its first description by Nisumaa et al. (2010). Most of study sites from which data archived are still in the Northern Hemisphere and the number of archived data from studies from the Southern Hemisphere and polar oceans are still relatively low. Data from 60 studies that investigated the response of a mix of organisms or natural communities were all added after 2010, indicating a welcomed shift from the study of individual organisms to communities and ecosystems. The initial imbalance of considerably more data archived on calcification and primary production than on other processes has improved. There is also a clear tendency towards more data archived from multifactorial studies after 2010. For easier and more effective access to ocean acidification data, the ocean acidification community is strongly encouraged to contribute to the data archiving effort, and help develop standard vocabularies describing the variables and define best practices for archiving ocean acidification data.

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In my thesis, “Commandeering Aesop’s Bamboo Canon: A 19th Century Confederacy of Creole Fugitive Fables,” I ask and answer the ‘Who? What? Where? When? Why?” of Creole Literature using the 19th century production of Aesopian fables as clues to resolve a set of linguistic, historical, literary, and geographical enigmas pertaining the ‘birth-place(s)’ of Creolophone Literatures in the Caribbean Sea, North and South America, as well as the Indian Ocean. Focusing on the fables in Martinique (1846), Reunion Island (1826), and Mauritius (1822), my thesis should read be as an attempt capture the links between these islands through the creation of a particular archive defined as a cartulary-chronicle, a diplomatic codex, or simply a map in which I chart and trace the flight of the founding documents relating to the lives of the individual authors, editors, and printers in order to illustrate the articulation of a formal and informal confederation that enabled the global and local institutional promotion of Creole Literature. While I integrate various genres and multi-polar networks between the authors of this 19th century canon comprised of sacred and secular texts such as proclamations, catechisms, and proverbs, the principle literary genre charted in my thesis are collections of fables inspired by French 17th century French Classical fabulist, Jean de la Fontaine. Often described as the ‘matrix’ of Creolophone Literature, these blues and fables constitute the base of the canon, and are usually described as either ‘translated,’ ‘adapted,’ and even ‘cross-dressed’ into Creole in all of the French Creolophone spaces. My documentation of their transnational sprouting offers proof of an opaque canonical formation of Creole popular literature. By constituting this archive, I emphasize the fact that despite 200 years of critical reception and major developments and discoveries on behalf of Creole language pedagogues, literary scholars, linguists, historians, librarians, archivist, and museum curators, up until now not only have none have curated this literature as a formal canon. I also offer new empirical evidence in order to try and solve the enigma of “How?” the fables materially circulated between the islands, and seek to come to terms with the anonymous nature of the texts, some of which were published under pseudonyms. I argue that part of the confusion on the part of scholars has been the result of being willfully taken by surprise or defrauded by the authors, or ‘bamboozled’ as I put it. The major paradigmatic shift in my thesis is that while I acknowledge La Fontaine as the base of this literary canon, I ultimately bypass him to trace the ancient literary genealogy of fables to the infamous Aesop the Phrygian, whose biography – the first of a slave in the history of the world – and subsequent use of fables reflects a ‘hidden transcript’ of ‘masked political critique’ between ‘master and slave classes’ in the 4th Century B.C.E. Greece.

This archive draws on, connects and critiques the methodologies of several disciplinary fields. I use post-colonial literary studies to map the literary genealogies Aesop; use a comparative historical approach to the abolitions of slavery in both the 19th century Caribbean and the Indian Ocean; and chart the early appearance of folk music in early colonial societies through Musicology and Performance Studies. Through the use of Sociolinguistics and theories of language revival, ecology, and change, I develop an approach of ‘reflexive Creolistics’ that I ultimately hope will offer new educational opportunities to Creole speakers. While it is my desire that this archive serves linguists, book collectors, and historians for further scientific inquiry into the innate international nature of Creole language, I also hope that this innovative material defense and illustration of Creole Literature will transform the consciousness of Creolophones (native and non-native) who too remain ‘bamboozled’ by the archive. My goal is to erase the ‘unthinkability’ of the existence of this ancient maritime creole literary canon from the collective cultural imaginary of readers around the globe.

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In recent years, some of the ramifications of the ocean acidification problematic derived from the anthropogenic rising of atmospheric CO2 have been widely studied. In particular, the potential effects of a lowering pH on tropical coral reefs have received special attention. However, only a few studies have focused on testing the effects of ocean acidification in corals from the Mediterranean Sea, despite the fact that this basin is especially sensitive to increasing atmospheric CO2. In this context, we investigated the response to ocean acidification of the two zooxanthellate coral species capable of constituting the main framework of the community, the endemic Cladocora caespitosa and the non-native Oculina patagonica. To this end, we examined the response of both species to pCO2 concentrations expected by the end of the century, 800 ppm, vs the present levels. Calcification rate measurements after 92 days of exposure to low pH conditions showed the same negative response in both species, a decrease of 32-35% compared to corals reared under control conditions. In addition, we detected in both species a correlation between the calcification rate of colonies in control conditions and the degree of impairment of the same colonies at low pH. Independent of species, faster growing colonies were more affected by decreased pH. After this period of decreased pH, we conducted a recovery experiment, in which corals reared in the acidic treatment were brought back to control conditions. In this case, normal calcification rates were reached in both species. Overall, our results suggest that O. patagonica and C. caespitosa will both be affected detrimentally by progressive ocean acidification in the near future. They do not display differences in response between native and non-native species but do manifest differential responses depending on calcification rate, pointing to a role of the coral genetics in determining the response of corals to ocean acidification.

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Understanding the reasons for long-term population change in a species requires an evaluation of ecological variables that may account for the observed dynamics. In this study, long-term changes in indices of Smallmouth Bass condition and population levels were examined for eastern Lake Ontario and the Bay of Quinte. Smallmouth Bass are an extremely important recreational fish species native to Lake Ontario. They have experienced numerous changes in their environment through direct human impacts, climate change, predation, and habitat sharing with non-native species. Smallmouth Bass have experienced an increase in body length and weight likely due to a diet shift from crayfish to predominantly Round Gobies which has allowed them to increase their growth rate. According to existing assessment data however, this increase in body size has not been associated with an increase in abundance. Long-term data from gill net sampling shows that Smallmouth Bass populations have been declining since the late 1980s with no indication of recovery. This could be due to a variety of factors, but it is most likely due to a change in the selectivity of gill nets because of the change in body size as well as a habitat shift away from gill net sampling sites. Adjusting for gill net selectivity has revealed that sub-adult bass abundance is currently greater than it was historically, and that very large bass are likely not being retained within the gill nets that are currently used. The use of a long-term data set in this study has led to a much better understanding of Smallmouth Bass abundance and ecology.

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Migration is as old as humanity, but since the 1990s migration flows in Western Europe have led to societies that are not just multicultural but so-called «super-diverse». As a result, Western towns now have very complex social structures, with amongst others large amounts of small immigrant communities that are in constant change. In this paper we argue that for social workers to be able to offer adequate professional help to non-native residents in town, they will need balanced view of ‘culture’ and of the role culture plays in social aid. Culture is never static, but is continually changing. By teaching social workers about how to look at cultural backgrounds of immigrant groups and about the limitations of then role that culture plays in communication, they will be better equipped to provide adequate aid and will contribute to making various groups grow towards each other and to avoid people thinking in terms of ‘out-group-homogeneity’. Nowadays, inclusion is a priority in social work that almost every social worker supports. Social workers should have an open attitude to allow them to approach every individual as a unique person. They will see the other person as the person they are, and not as a part of a specific cultural group. Knowledge about the others makes them see the cultural heterogeneity in every group. The social sector, though, must be aware not to fall into the trap of the ‘inclusion mania’! This will cause the social deprivation of a particular group to be forgotten. An inclusive policy requires an inclusive society. Otherwise, this could result in even more deprivation of other groups, already discriminated against. Emancipation of deprived people demands a certain target-group policymaking. Categorized aid will raise efficiency of working with immigrants and of acknowledging the cultural identity of the non-natives group. It will also create the possibility to work on fighting social deprivation, in which most immigrants can be found.

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Human-mediated dispersal interplays with natural processes and complicates understanding of the biogeographical history of species. This is exemplified by two invasive tunicates, Ciona robusta (formerly Ciona intestinalis type A) and C. intestinalis (formerly Ciona intestinalis type B), globally distributed and sympatric in Europe. By gathering new mitochondrial sequences that were merged with published datasets, we analysed genetic patterns in different regions, with a focus on 1) their sympatric range and 2) allopatric populations in N and S America and southern Europe. In the sympatric range, the two species display contrasting genetic diversity patterns, with low polymorphism in C. robusta supporting the prevalent view of its recent introduction. In the E Pacific, several genetic traits support the non-native status of C. robusta. However, in the NE Pacific, this appraisal requires a complex scenario of introduction and should be further examined supported by extensive sampling efforts in the NW Pacific (putative native range). For C. intestinalis, Bayesian analysis suggested a natural amphi-North Atlantic distribution, casting doubt on its non-native status in the NW Atlantic. This study shows that both natural and human-mediated dispersal have influenced genetic patterns at broad scales; this interaction lessens our ability to confidently ascertain native vs. non-native status of populations, particularly of those species that are globally distributed.

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Human-mediated dispersal interplays with natural processes and complicates understanding of the biogeographical history of species. This is exemplified by two invasive tunicates, Ciona robusta (formerly Ciona intestinalis type A) and C. intestinalis (formerly Ciona intestinalis type B), globally distributed and sympatric in Europe. By gathering new mitochondrial sequences that were merged with published datasets, we analysed genetic patterns in different regions, with a focus on 1) their sympatric range and 2) allopatric populations in N and S America and southern Europe. In the sympatric range, the two species display contrasting genetic diversity patterns, with low polymorphism in C. robusta supporting the prevalent view of its recent introduction. In the E Pacific, several genetic traits support the non-native status of C. robusta. However, in the NE Pacific, this appraisal requires a complex scenario of introduction and should be further examined supported by extensive sampling efforts in the NW Pacific (putative native range). For C. intestinalis, Bayesian analysis suggested a natural amphi-North Atlantic distribution, casting doubt on its non-native status in the NW Atlantic. This study shows that both natural and human-mediated dispersal have influenced genetic patterns at broad scales; this interaction lessens our ability to confidently ascertain native vs. non-native status of populations, particularly of those species that are globally distributed.

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This paper is a study about the way in which se structures are represented in 20 verb entries of nine dictionaries of Spanish language. There is a large number of these structures and they are problematic for native and non native speakers. Verbs of the analysis are middle-high frequency and, in the most part of the cases, very polysemous, and this allows to observe interconnections between the different se structures and the different meanings of each verb. Data of the lexicographic analysis are cross-checked with corpus analysis of the same units. As a result, it is observed that there is a large variety in the data which are offered in each dictionary and in the way they are offered, inter and intradictionary. The reasons range from the theoretical overall of each Project to practical performance. This leads to the conclusion that it is necessary to further progress in the dictionary model it is being handled, in order to offer lexico-grammatical phenomenon such as se verbs in an accurate, clear and exhaustive way.

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With the development of information technology, the theory and methodology of complex network has been introduced to the language research, which transforms the system of language in a complex networks composed of nodes and edges for the quantitative analysis about the language structure. The development of dependency grammar provides theoretical support for the construction of a treebank corpus, making possible a statistic analysis of complex networks. This paper introduces the theory and methodology of the complex network and builds dependency syntactic networks based on the treebank of speeches from the EEE-4 oral test. According to the analysis of the overall characteristics of the networks, including the number of edges, the number of the nodes, the average degree, the average path length, the network centrality and the degree distribution, it aims to find in the networks potential difference and similarity between various grades of speaking performance. Through clustering analysis, this research intends to prove the network parameters’ discriminating feature and provide potential reference for scoring speaking performance.

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At a global scale, aquatic ecosystems are being altered by human activities at a greater rate than at any other time in history. In recent years, grassroots efforts have generated interest in the restoration of degraded or destroyed aquatic habitats, especially small wetlands and streams where such projects are feasible with local resources. We present ecological management lessons learned from 17 years of monitoring the fish community response to the channel relocation and reach-level restoration of Juday Creek, a 3rd-order tributary of the St. Joseph River in Indiana, USA. The project was designed to increase habitat complexity, reverse the effects of accumulated fine sediment (< 2 mm diameter), and mitigate for the impacts of a new golf course development. The 1997 restoration consisted of new channel construction within two reaches of a 1.2-km section of Juday Creek that also contained two control reaches. A primary social goal of the golf course development and stream restoration was to avoid harm to the non-native brown trout fishery, as symbolic of community concerns for the watershed. Our long-term monitoring effort revealed that, although fine sediment increased over time in the restored reaches, habitat conditions have promoted the resurgence of native fish species. Since restoration, the fish assemblage has shifted from non-native Salmonidae (brown trout, rainbow trout) to native Centrarchidae (rock bass, largemouth bass, smallmouth bass). In addition, native, nongame species have remained stable or have increased in population abundance (e.g., Johnny darter, mottled sculpin). The results of this study demonstrate the value of learning from a restoration project to adjust management decisions that enhance environmental quality.

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Thesis (Master's)--University of Washington, 2016-06

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This thesis is a case study of a primary school in a highly diverse urban neighbourhood in Sweden. Basic pre-conditions for intercultural school development are studied by examining the overall organisation of teaching, learning and opportunities for collaboration in the investigated case. The study focuses on the targeted support measures to enhance learning for students with an immigrant background: Mother tongue instruction, Swedish as a Second Language, and tutoring in the mother tongue, as well as looking at pedagogical support provided by the school library. The latter has a mission to promote learning and inclusion, where non-native speakers of Swedish are a prioritised group. Communities of practice linked to the work organisation at a meso-level are investigated, and the collaborative relationships between professional groups at the school involved in the various support measures. Teacher relationships and categorisations implied by support measures impact the learning spaces that are shaped for students and the teaching spaces within which teachers work. Collaborative opportunities and convergence of concerns in the teaching spaces combine to shape the overall space for intercultural development. The raw data for the case study consists of interviews, national policy documents and additional information on local work organisation gained through documents and observations. Four articles resulted from the case study, each focusing a specific support measure. An overarching analysis is then made of findings from these articles and the other dimensions of the investigation. The analysis describes the organisation in terms of monocultural or intercultural school cultures, pointing to significant characteristics of the landscapes of practice, with respect to their overall implications for the spaces of school development. In the discussion, findings are considered in relation to research on professional development in education, collaboration, democracy and inclusive schooling. The relative positioning of languages and cultures is given particular attention, to ascertain if the school culture is monocultural or intercultural in the sense given by Lahdenperä (2008), and to what extent it could enable intercultural development. Such positioning plays a role interms of affordances for identity, participation and engagement discussed by Wenger (1998). This case study should be understood against the wider background of recent social developments in Europe linked to globalisation and technological changes. It is argued that looking at the concrete specifics which facilitate or obstruct school development, and simultaneously reflecting on how the different forms of teaching interrelate in the overall organisation and in policy may provide a useful vantage point from which structural changes can be contemplated.The discussion underlines the importance of the physical localisation of activities, continuity in personal contacts and time available for joint pedagogical reflection, as basic conditions for effective intercultural dialogue in the organisation. Finally, the impact of policy is considered, looking at connections between levels of policy, expressed in official steering documents, and conditions for teaching and learning at the level of an individual school.

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This dissertation investigates the acquisition of oblique relative clauses in L2 Spanish by English and Moroccan Arabic speakers in order to understand the role of previous linguistic knowledge and its interaction with Universal Grammar on the one hand, and the relationship between grammatical knowledge and its use in real-time, on the other hand. Three types of tasks were employed: an oral production task, an on-line self-paced grammaticality judgment task, and an on-line self-paced reading comprehension task. Results indicated that the acquisition of oblique relative clauses in Spanish is a problematic area for second language learners of intermediate proficiency in the language, regardless of their native language. In particular, this study has showed that, even when the learners’ native language shares the main properties of the L2, i.e., fronting of the obligatory preposition (Pied-Piping), there is still room for divergence, especially in production and timed grammatical intuitions. On the other hand, reaction time data have shown that L2 learners can and do converge at the level of sentence processing, showing exactly the same real-time effects for oblique relative clauses that native speakers had. Processing results demonstrated that native and non-native speakers alike are able to apply universal processing principles such as the Minimal Chain Principle (De Vincenzi, 1991) even when the L2 learners still have incomplete grammatical representations, a result that contradicts some of the predictions of the Shallow Structure Hypothesis (Clahsen & Felser, 2006). Results further suggest that the L2 processing and comprehension domains may be able to access some type of information that it is not yet available to other grammatical modules, probably because transfer of certain L1 properties occurs asymmetrically across linguistic domains. In addition, this study also explored the Null-Prep phenomenon in L2 Spanish, and proposed that Null-Prep is an interlanguage stage, fully available and accounted within UG, which intermediate L2 as well as first language learners go through in the development of pied-piping oblique relative clauses. It is hypothesized that this intermediate stage is the result of optionality of the obligatory preposition in the derivation, when it is not crucial for the meaning of the sentence, and when the DP is going to be in an A-bar position, so it can get default case. This optionality can be predicted by the Bottleneck Hypothesis (Slabakova, 2009c) if we consider that these prepositions are some sort of functional morphology. This study contributes to the field of SLA and L2 processing in various ways. First, it demonstrates that the grammatical representations may be dissociated from grammatical processing in the sense that L2 learners, unlike native speakers, can present unexpected asymmetries such as a convergent processing but divergent grammatical intuitions or production. This conclusion is only possible under the assumption of a modular language system. Finally, it contributes to the general debate of generative SLA since in argues for a fully UG-constrained interlanguage grammar.

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Aim The spread of non-indigenous species in marine ecosystems world-wide is one of today's most serious environmental concerns. Using mechanistic modelling, we investigated how global change relates to the invasion of European coasts by a non-native marine invertebrate, the Pacific oyster Crassostrea gigas. Location Bourgneuf Bay on the French Atlantic coast was considered as the northern boundary of C. gigas expansion at the time of its introduction to Europe in the 1970s. From this latitudinal reference, variations in the spatial distribution of the C. gigas reproductive niche were analysed along the north-western European coast from Gibraltar to Norway. Methods The effects of environmental variations on C. gigas physiology and phenology were studied using a bioenergetics model based on Dynamic Energy Budget theory. The model was forced with environmental time series including in situ phytoplankton data, and satellite data of sea surface temperature and suspended particulate matter concentration. Results Simulation outputs were successfully validated against in situ oyster growth data. In Bourgneuf Bay, the rise in seawater temperature and phytoplankton concentration has increased C. gigas reproductive effort and led to precocious spawning periods since the 1960s. At the European scale, seawater temperature increase caused a drastic northward shift (1400 km within 30 years) in the C. gigas reproductive niche and optimal thermal conditions for early life stage development. Main conclusions We demonstrated that the poleward expansion of the invasive species C. gigas is related to global warming and increase in phytoplankton abundance. The combination of mechanistic bioenergetics modelling with in situ and satellite environmental data is a valuable framework for ecosystem studies. It offers a generic approach to analyse historical geographical shifts and to predict the biogeographical changes expected to occur in a climate-changing world.