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101.
In this article I suggest that a reading of previous studies, which cast the early transfers of eucalyptus to South Africa along economic and aesthetic rationales can be enhanced by medical history. Through a case from King William’s Town in the 1870s, I show that the appeal of the eucalyptus hinged on the olfactory aspect of the trees, which were conceived as an important public health factor. I then proceed to outline how a clearer understanding of the role of olfaction in ecological studies can uncover new aspects of social dynamics and human relations to the natural environment. I argue that taking the atmosphere seriously as the medium through which we interact with the world, opens for an understanding of olfaction as an important and largely unexplored ethos that guided the dramatic reshaping of the colonial landscapes during much of the nineteenth century.  相似文献   
102.
吕金波  李勇 《城市地质》2016,(3):96-104
北京地貌呈现"北京湾"特征,北山产铁,西山产煤,平原产地热。地质大厦院内东侧花坛摆放代表地球从老到新5个代(宙)的岩石,西侧花坛摆放阳坊花岗岩,体现了地质学为首都城市发展的贡献。太古代密云岩群表壳岩铁矿曾为首钢铁矿的主要原料,元古代雾迷山组汉白玉大理岩曾用于古都北京的建设,古生代马家沟组石灰岩中流出了优质饮用水,中生代窑坡组煤矿使西山成为中国地质工作的摇篮,新生代马兰黄土是中国最早研究的黄土,中生代形成的阳坊花岗岩曾用于北京1959年十大建筑的基石。  相似文献   
103.
The transformation of tropical ecosystems by humans have resulted in forest loss, which, in turn, have caused negative impacts on biodiversity and the provisioning of ecosystem services. There is an urgent need to plan the restoration of these human-modified landscapes, using methodological approaches that consider key processes occurring at different spatial scales while engage local community participation, offering them the best possibilities of tangible benefits. In this study, was evaluated the landscape spatial pattern and local conservation status of existing forest remnants, showing an analysis of possible restoration scenarios for a human-modified landscape in La Montaña, an indigenous region in southwestern Mexico. Therefore, landscape and local scale approaches were linked to identify specific landscape elements where efforts to improve connectivity must be concentrated. Also, this approach allowed finding a set of species from reference sites that showed the best socioecological characteristics to be used in different restoration strategies. As expected, La Montaña region showed a spatial pattern typical of highly human-modified landscapes, i.e., several small (<21 ha) and irregular forest remnants with strong forest edge effects. Furthermore, these small and irregular forest fragments displayed forest structure, diversity and composition characteristics similar to those communities disturbed by selective harvesting or in an early successional phase. However, about 100 of woody species were found inside the fragments, some with important potential to provide ecosystem services. The landscape connectivity was very low, and an analysis of possible restoration scenarios showed that is equally important to restore the productive areas as well as open forest, to recover up to 47% of landscape connectivity. In this sense, it was proposed a productive restoration strategy to enrich open forests and create biodiversity-friendly habitat in agricultural areas, using species with high socioecological potential. We believe that the same approach could be applied to other highly human-modified tropical landscapes with similar socioecological problems.  相似文献   
104.
Human well-being is an important concept for human-nature interactions and affected by social, ecologic, and personal factors. There is increasing consensus about the importance of public perceptions of human well-being, but studies on this are still scarce. Here, we conducted 445 face-to-face interviews to assess subjective well-being across diverse respondents and landscapes in the Huailai mountain-basin system, China. The results suggest the actualization process of human well-being is similar to Maslow's hierarchy of needs. We found that mental health was disregarded by most respondents, while basic material for a good life was most valued. Moreover, our results show differences of well-being across different socio-demographic and landscapes characteristics. Apart from good social relations, elderly respondents had highest levels of human well-being in all other four dimensions; respondents from mountainous land with a high level of ecological conservation had the lowest level of well-being. We discuss the factors contribution to well-being and its implications for local management and policies. Understanding the implications of respondents and landscapes characteristics on human well-being can help managers to develop efficient and specific policies.  相似文献   
105.
Different levels of climatic, agricultural, demographic, political and socioeconomic change have been detected in West African countries. For many years the human impact on the region was negligible, due to the low population density. However, in the last decades, demographic increase has accelerated exploitation of the natural resources and consequently the degradation of the ecosystems. Land cover degradation and landscape changes are more or less pronounced according to politic and socio-economic conditions of each country. In this study, a region located on the borderland of north Guinea-Bissau and south Senegal, is analyzed with regard to land cover and landscape trends, considering the socio-economic factors that drive them and the borderline effect. In this analysis, remote sensing data (Landsat TM, ETM+ and OLI data) were used to obtain four land cover maps for the years 1990, 2002, 2010 and 2015. The results show a similar landscape behavior in both countries, directly related to similar socio-economic practices. Forest area increase in both countries and there is a reduction in Agriculture/Bare soil areas until 2010. Main causes may be associated to the rural exodus, resulting from the conflict for independence of Casamance, which affects the borderland region of Senegal and Guinea Bissau, or to the conversion of agricultural areas into cashew orchards. In opposition, between 2010 and 2015, Forest area decrease and Agriculture/Bare soil increase, due to the recent trend of conversion of old cashew orchards into traditional fields of cereals and peanut. An increase in landscape fragmentation is observed in the period under analysis, revealing a heterogenization trend, which can be related to the adoption of similar human practices, in the last decades.  相似文献   
106.
In a context of neo-liberal environmental governance, imperatives for global climate change mitigation are motivating a new round of policy initiatives and projects aimed at carbon forestry: conserving and enhancing forest carbon stocks, and trading these values in emerging carbon markets. In this context modelling and measurement, always significant in framing and justifying forest policy initiatives, are of renewed importance, with a growing array of protocols focused on counting and accounting for forest carbon as a commodity. This article draws on perspectives from science and technology studies and environmental discourse analysis to explore how these modelling and measurement processes are being co-constructed with forest carbon policies and political economies, and applied in project design in local settings. Document analysis and key informant interviews are used to track and illustrate these processes in a pair of case studies of forest carbon projects in Sierra Leone and Ghana. These are chosen to highlight different project types – focused respectively on forest reserve and farm-forestry – in settings with multi-layered histories of people-forest relations, landscape change and prior project intervention. The analysis shows how longer established framings and assessments of deforestation are being re-invoked and re-worked amidst current carbon concerns. We demonstrate that measurement processes are not just technical but social and political, carrying and thus cementing particular views of landscape and social relations that in turn make likely particular kinds of intervention pathway, with fortress style conservation or plantations becoming the dominant approach. In the process, other possibilities – including alternative pathways that might treat and value carbon as part of complex, lived-in landscapes, or respond more adaptively to less equilibrial people–forest relations, are occluded.  相似文献   
107.
We have investigated almost 200 years of landscape transformations in a traditional brown coal mining region in northwest Bohemia, Czech Republic. The investigation was focused on the central part of the North Bohemian Basin including 44 cadastral areas representing a total area of 228.48 km2. Within this area, an analysis of land use in six different time periods (1845, 1954, 1975, 1989, 2010, 2050) was performed. The analysis therefore includes the transitory period of a boom and slow-down of surface coal mining and also provides a unique comparison with the planned future condition of the landscape after the year 2050, when the mines have been closed down and the landscape restored. Practically all available geographic data resources on land use have been used – the stable cadastre, topographic maps, current landscape mapping and aerial photographs. We differentiated twelve land-use categories. Both Friedman test and detrended correspondence analysis show significant differences in the representation of individual land-use categories and characteristics of the landscape before and during mining operations and after their discontinuance and revitalisation of spoil tips and in residual pits. For a long period of time, agricultural landscape was changed into an industrial one. The basin part of the studied territory almost completely lacks eco-stabilising features that could be used as a basis for planning of a new landscape. This is because the original landscape had been intensively used for agriculture previously, and almost one half of the territory was over-exploited and other areas were affected by operation facilities and coal processing industrial plants. With the growing number of reclamation projects, the diversity of the landscape has been increasing, as well as the proportion of ecologically valuable elements (mostly forests and water bodies), whose total area could exceed 70% of the landscape's surface in the future, approximating its characteristics to a natural landscape with a high degree of ecological stability.  相似文献   
108.
To ensure successful conservation of ecological and cultural landscape values, detailed and up-to-date spatial information of existing habitat patterns is essential. However, traditional satellite-based and raster classifications rely on pixels that are assigned to a single category and often generalized. For many fragmented key habitats, such a strategy is too coarse and complementary data is needed. In this paper, we aim at detecting pixel-wise fractional coverage of broadleaved woodland and grassland components in a hemiboreal landscape. This approach targets ecologically relevant deciduous fractions and complements traditional crisp land cover classifications. We modeled fractional components using a k-NN approach, which was based on multispectral satellite data, assisted by a digital elevation model and a contemporary map database. The modeled components were then analyzed based on landscape structure indicators, and evaluated in conjunction with CORINE classification. The results indicate that both broadleaved forest and grassland components are widely distributed in the study area, principally organized as transition zones and small patches. Landscape structure indicators show a substantial variation based on the fractional threshold, pinpointing their dependency on the classification scheme and grain. The modeled components, on the other hand, suggest high internal variation for most CORINE classes, indicating their heterogeneous appearance and showing that the presence of deciduous components in the landscape are not properly captured in a coarse land cover classification. To gain a realistic perception of the landscape, and use this information for the needs of spatial planning, both fractional results and existing land cover classifications are needed. This is because they mutually contribute to an improved understanding of habitat patterns and structures, and should be used to complement each other.  相似文献   
109.
The influence of relative sediment supply on riverine habitat heterogeneity   总被引:1,自引:0,他引:1  
The diversity of aquatic habitats in streams is linked to physical processes that act at various spatial and temporal scales. Two components of many that contribute to creating habitat heterogeneity in streams are the interaction between sediment supply and transport capacity and the presence of local in-stream structures, such as large woody debris and boulders. Data from previously published flume and field studies and a new field study on tributaries to the South Yuba River in Nevada County, California, USA, were used to evaluate the relationship between habitat heterogeneity, local in-stream structural features and relative sediment supply. Habitat heterogeneity was quantified using spatial heterogeneity measures from the field of landscape ecology. Relative sediment supply, as expressed by the sediment supply/transport capacity ratio, which controls channel morphology and substrate textures, two key physical habitat characteristics, was quantified using a dimensionless bedload transport ratio, q. Calculated q values were plotted against an ecologically meaningful heterogeneity index, Shannon's Diversity Index, measured for each study reach, as well as the percent area of in-stream structural elements. The results indicate two potential mechanisms for how relative sediment supply may drive geomorphic diversity in natural river systems at the reach scale. When less mobile structural elements form a small proportion of the reach landscape, the supply/capacity ratio dictates the range of sediment textures and geomorphic features observed within the reach. In these settings, channels with a moderate relative sediment supply exhibit the highest textural and geomorphic diversity. In contrast, when less mobile structural elements are abundant, forced local scour and deposition creates high habitat heterogeneity, even in the presence of high relative sediment supply.  相似文献   
110.
The multiple interfaces of the European Landscape Convention were the topic of a roundtable panel discussion held at the meeting of the Permanent European Conference for the Study of the Rural Landscape in September 2006. The roundtable was convened by Kenneth R. Olwig, who together with four other speakers presented the main topics for discussion. Their presentations are given here as a series of short articles. Initially a brief historical background and the main provisions of the European Landscape Convention (Florence Convention) of 2000, in force 2004, are presented. The interfaces with law, landscape ecology, heritage, and globalisation are then successively discussed. Finally, the European Landscape Convention itself is examined as a discursive interface, with contradictory as well as synergetic aspects.  相似文献   
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