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41.
    
Invasive vegetation species can lead to major changes in the geomorphology of coastal systems. Within temperate estuaries in the southern hemisphere, especially Australia and New Zealand, the cordgrass Spartina spp. has become established. These species are highly invasive, and their prolific growth leads to the development of supratidal environments in formerly intertidal and subtidal environments. Here, we quantified the impact of Spartina invasion on the geomorphology and sequestration capacity of carbon in the sediments of Anderson Inlet, Victoria, Australia. Spartina was first introduced to the area in the 1930s to aid in land reclamation and control coastal erosion associated with coastal development. We found that Spartina now dominates the intertidal areas of the Inlet and promotes accretion (18 mm/year) causing the formation of over 108 ha of supratidal islands over the past 100 years. These newly formed islands are calculated to potentially contain over 5.5 million tonnes of CO2 equivalent carbon. Future management of the inlet and other Spartina‐dominated environments within Australian presents a dilemma for resource managers; on the one hand, Spartina is highly invasive and can outcompete native tidal marshes, thereby warranting its eradication, but on the other hand it is likely more resilient to rising sea levels and has the potential for carbon sequestration. Whether or not the potential advantages outweigh the significant habitat change that is anticipated, any management strategies will likely require additional research into costs and benefits of all ecosystem services provided by Spartina including in relation to nutrient cycling, shoreline stabilisation, and biodiversity as well as in response to the longevity of carbon found within the sediments.  相似文献   
42.
    
ABSTRACT

Along Florida’s nearly 13,000 km of shoreline, nearly 4000 archaeological sites and over 600 recorded historic cemeteries are at risk from climate change impacts including coastal erosion and a 2-metre rise in sea level. In 2016, the Florida Public Archaeology Network (FPAN) created the Heritage Monitoring Scouts (HMS Florida) programme to engage the public in monitoring sites at risk. The programme grew quickly during the first year of operation to include 233 volunteers who submitted 312 monitoring forms. The programme exists beyond the singular act of a volunteer reporting site conditions; across Florida, varied combinations of local partnerships present unique opportunities for programmes, for example, the pilot program at the Guana Tolomato Matanzas National Estuarine Research Reserve. Preliminary outcomes from the first year of HMS Florida and the pilot indicate the programme is effective in public engagement and a powerful management tool for tracking change to sites over time.  相似文献   
43.
    
ABSTRACT

Climate change impacts will increase in their frequency and severity in the coming decades, resulting in compromised integrity or destruction of thousands of heritage resources. Efforts are needed to identify, record, and study resources that will be affected. To set research and preservation priorities, the vulnerability of resources to climate change impacts and their importance to scientific research, preservation, and other resource values needs to be understood. We advocate a modelling approach which predicts the location, timing, and severity of climate change impacts; identifies resources at risk, their resource values, and opportunity costs; and prioritises research and preservation options based on these assessments. The need for this approach is illustrated with examples from two coastal areas subject to different impacts and hosting different types of heritage resources: the Atlantic coast of Georgia in the United States and the Wismar Bight along the Baltic Sea in northern Germany.  相似文献   
44.
    
As in other European countries, the formal planning task of Dutch governments is subjected to devolution and austerity measures. Not only did these developments lead to outsourcing planning tasks to lower-level governments, also citizens are increasingly ‘invited’ to take responsibility for providing public facilities and services. In De Achterhoek, a Dutch region, these shifts are amplified due to population change and traditional active citizenship, and led to institutional change. Since a decade local governments stimulate citizen initiatives, under the umbrella of participatory governance. This process of institutional change did not alter formal institutions, but was the result of an informal and dialectic process between local governments and citizen organizations. In this paper, we will demonstrate the process of change and how it affected planning practices in De Achterhoek, building on theories of informal institutional change and its driving forces. The empirical part of this paper draws on the results of three focus group meetings, in which a diverse set of local stakeholders discussed the effects of change they observed and how it shaped planning practices. In the final section, we reflect on the degree of institutionalization, by examining the robustness and resilience of the observed change.  相似文献   
45.
    
Non-urbanized areas (NUAs) play an important role in reducing the effects of climate change by providing both carbon storage and sequestration. Urban areas are responsible for the emission of 60% of global greenhouse gas, 50% of which are produced by buildings. During the past decades, increasing urban growth and sprawl processes produced several urban layouts characterized by different morphological features and a common lack of sustainable energy and environmental solutions. Investigating the relationship between urban morphology, energy demand and carbon emission/sequestration represents a relevant topic for urban planning practices implemented to face urban climate change effects. This study proposes a method for a transformability assessment aimed at investigating the transformation suitability of different urban morphology types. The case study is the metropolitan area of Catania (Italy), characterized by an impressive urban growth since the 1960s. The proposed method identification of limits and options for increasing sustainability of urban areas considering the contribution of both NUAs and built-up areas. This approach allows to identify appropriate planning tools for new layouts of urban fabrics while increasing the objectivity of the decision process. In the framework of climate change mitigation and adaptation, the outcomes of this research may lead to innovative urban planning practices.  相似文献   
46.
Based on ethnographic data gathered over 12 months of fieldwork with unmarried women living alone or in flat-shares in different middle class South Delhi localities, this article traces the way shifting gendered norms – often epitomized by growing numbers of single women households – are negotiated within class specific and highly localized contexts of the residential neighborhood. Despite growing economic opportunities for middle class and elite women, cultural anxieties surrounding the notion of ‘delayed’ marriage and women living outside of the familial or marital home persist and obstruct attempts at establishing independent households. Single women experience difficulties finding apartments to rent; have to contend with hostile intrusions from neighbors; or feel obliged to self-monitor their behavior within their neighborhoods. As South Delhi’s liberalised urban landscape has become home to an increasingly globalized, consumerist middle class, disciplinary measures such as curfews, regulations over houseguests and increased surveillance simultaneously indicate a middle class recalibrating its gendered social coordinates by proving its commitment to values of female propriety. While popular discourses draw juxtaposed imaginaries of the ‘modern’ and the ‘traditional’ in their depictions of increasing individualism and a loosening of ‘traditional’ role expectations, this article demonstrates the need to consider the different structural conditions and local inflections in which struggles over women’s agency take place. Looking beyond the supposedly universalizing forces of globalized consumer modernity, the residential neighborhood hereby provides a view into the lived experiences of – at times incongruous – mechanisms at play in societies undergoing social change.  相似文献   
47.
    
In the context of global warming, changes in extreme weather and climate events are expected, particularly those associated with changes in temperature and precipitation regimes and those that will affect coastal areas. The main objectives of this study were to establish the number of extreme events that have occurred in northeastern New Brunswick, Canada in recent history, and to determine whether their occurrence has increased. By using archived regional newspapers and data from three meteorological stations in a national network, the frequency of extreme events in the study area was established for the time period 1950–2012. Of the 282 extreme weather events recorded in the newspaper archives, 70% were also identified in the meteorological time series analysis. The discrepancy might be explained by the synergistic effect of co‐occurring non‐extreme events, and increased vulnerability over time, resulting from more people and infrastructure being located in coastal hazard zones. The Mann Kendall and Pettitt statistical tests were used to identify trends and the presence of break points in the weather data time series. Results indicate a statistically significant increase in average temperatures and in the number of extreme events, such as extreme hot days, as well as an increase in total annual and extreme precipitation. A significant decrease in the number of frost‐free days and extreme cold days was also found, in addition to a decline in the number of dry days.  相似文献   
48.
ABSTRACT

Attending to Poly-Olbion’s river dynamics, I argue that, implicitly opposing natural, inevitable unionization, Drayton demonstrates through visual and poetic means that any viable empire is forged by deliberate local choices about conjunction and affiliation. Further, I show that by reconfiguring Saxton’s maps, rejecting politically defined boundaries and perceptions, and situating three major rivers as the organizing features of the landscape and the empire, Drayton ultimately defines Britain as inherently and universally maritime. Moreover, linking Poly-Olbion to mare clausum and mare liberum debates, I reveal that Drayton situates the flow of self-aware rivers into the sea as an extension of Britain beyond its land boundaries. He thereby suggests that the eventual mixing of British waters with the larger oceans establishes the basis of Britain’s local and global maritime rights, linking regional autonomy and conjunction by choice with claims to both local offshore dominion and global freedom of navigation and trade.  相似文献   
49.
内蒙古中南部考古学文化演变的环境学透视   总被引:2,自引:0,他引:2  
魏峻 《华夏考古》2005,(1):62-68
内蒙古中南部位于我国北方农牧交错带的中段, 是气侯变化的敏感地区。全新世以来的气侯波动, 对于塑造这里的自然景观和古文化的面貌起着重要的作用。本文分析了全新世大暖期的不同时段上古文化的特点和生计方式的变化, 并从沙地进退、湖面升降的视角探讨了这一地区考古学文化的演变以及人地之间相互作用的过程。  相似文献   
50.
Tuvalu, a place whose image in the ‘West’ is as a small island state, insignificant and remote on the world stage, is becoming remarkably prominent in connection with the contemporary issue of climate change‐related sea‐level rise. My aim in this paper is to advance understanding of the linkages between climate change and island places, by exploring the discursive negotiation of the identity of geographically distant islands and island peoples in the Australian news media. Specifically, I use discourse analytic methods to critically explore how, and to what effects, various representations of the Tuvaluan islands and people in an Australian broadsheet, the Sydney Morning Herald, emphasize difference between Australia and Tuvalu. My hypothesis is that implicating climate change in the identity of people and place can constitute Tuvaluans as .tragic victims. of environmental displacement, marginalizing discourses of adaptation for Tuvaluans and other inhabitants of low‐lying islands, and silencing alternative constructions of Tuvaluan identity that could emphasize resilience and resourcefulness. By drawing attention to the problematic ways that island identities are constituted in climate change discourse in the news media, I advocate a more critical approach to the production and consumption of representations of climate change.  相似文献   
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