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11.
生物标志化合物对东、西太湖不同湖泊类型的判识   总被引:6,自引:0,他引:6  
从生物标志化合物的角度,对东、西太湖沉积物中饱和烃组分进行了分析,通过对其正构烷烃碳数分布形式,主峰碳位置、L/H等指标对比,对照西太湖中的主要水生植物蓝藻和东太湖中的主要水生植物的饱和烃的组成特征,同时结合常规指标C/N的分析结果,对东、西太湖湖泊类型进行判识-西太湖为藻型湖泊,东太湖为草型湖泊。  相似文献   
12.
The methods and analytical results for distinguishing lake types of East Taihu Lake and West Taihu Lake by biological markers were dealt in this paper.  相似文献   
13.
Peri-urban areas are usually a heterogeneous mosaic of rural, urban and natural systems which are quite dynamic across time. In this paper we contrast a static and a dynamic-based classification of local administrative units (LAU) in the Lisbon Metropolitan Area (LMA) to gain further insights onto the current land cover patterns and recent land cover changes in urban and peri-urban areas of the LMA. Using 16 landscape pattern indicators, we characterized the 211 LAU in the region contrasting a static (2006 data) and a dynamic-based (changes during the period 1990–2006) approach, and used cluster analyses to identify LAU typologies. Using the static approach we identified seven types of LAU, of which two were clearly urban, two could be considered rural, and three could be considered peri-urban. These latter could be distinguished among themselves by the landscape matrix type where urban areas were inserted. The dynamic-based approach yielded five types of LAU with specific trajectories in time, ranging from stable to highly dynamic. The frequency of the different dynamic typologies was not independent from the static ones, with typically urban areas being predominantly stable and rural areas having characteristic and exclusive trajectories of change. Peri-urban LAU were mostly moderately dynamic but shared a typology profile mixing highly dynamic LAU with moderately dynamic and stable ones. The combination of a static and dynamic view provides added value for the formulation of spatial planning policies in peri-urban areas.  相似文献   
14.
The abiotic typology of Polish lakes, compliant with the requirements of the EU Directive 2000/60/EC (Water Framework Directive), was developed in 2004 under the commission of the Ministry of the Environment. Based on the combination of the obligatory typological criteria from Annex II of the WFD and one additional factor, all Polish lakes larger than 0.5 km2 were assigned to 13 abiotic types. This typology reflected the diversity of abiotic conditions and was assumed to be tested and validated for its ecological relevance on the basis of biological data obtained thereafter. The first ten years of its application proved the high usability of this typology for lake classification of ecological status on the one hand, while on the other hand, it allowed to gather experiences and to detect deficiencies and errors considered in the verification process. In 2015, the abiotic typology of Polish lakes was verified. Above all, verification involved an analysis of the justification of lake eco-regional division and refinement of water stratification criteria, as these two issues have been questioned in the current typology. Data on physicochemical properties, phytoplankton, macrophytes and benthic diatoms obtained from the state lake monitoring conducted in the years 2007–2013 were used to verify the ecological relevance of the typological criteria. Typological criteria used in the verified lake typological scheme were essentially the same as those used in 2004. However, the number of lake types has been reduced from the previous 13 to seven, mainly due to the withdrawal from the lake division based on eco-regions. Moreover, the more specific criteria for determining the water mixing type were established. The new lake typology is expected to be implemented in routine monitoring and water management in Poland in the forthcoming River Basin Management Plan 2021–2027.  相似文献   
15.
Water scarcity and stress have attracted increasing attention as water has become increasingly regarded as one of the most critical resources in the world’s sustainable development. The Water Poverty Index (WPI), an interdisciplinary but straightforward measure that considers water availability from both the bio-geophysical perspective and the socio-economic perspective of people’s capacity to access water, has been successfully applied at national, regional, and local levels around the world. However, the general assessment of water stress at a macro level over only a snapshot limits the understanding of the geographic differences in and dynamics of water stress; this will, in turn, mislead decision-makers and may result in improper water strategies being implemented. In addition, to date, the typologies and trajectories of water stress have been underexplored. To fill this knowledge gap, we examine the spatio-temporal patterns, trajectories, and typologies of water stress using an adapted WPI for six counties in Zhangye City, which lies within an arid region of China, in order to provide policy priorities for each county. The results of our assessment indicate that water stress has become more severe over time (2005–2011) in most of the counties in Zhangye City. The results also show a distinct spatial variation in water scarcity and stress. Specifically, the results for Shandan county reflect its progressive policies on water access and management, and this county is regarded as engaging in good water governance. In contrast, Ganzhou district has faced more severe water pressure and is regarded as practicing poor water governance. Typology results show that each county faces its own particular challenges and opportunities in the context of water scarcity and stress. In addition, the trajectory map reveals that none of the counties has shown substantial improvement in both water access and management, a finding that should draw decision-makers’ close attention.  相似文献   
16.
17.
Urban planners frequently adhere to ‘park minimum standards’ to ensure that public health and environmental benefits associated with greenspace are socially equitable. These standards denote the extent and placement of greenspaces, but rarely consider their form and function. Arguably, an inclusive evaluation of greenspace social equity requires the comparison of greenspace types. To address if greenspace types are socially equitable, I develop a novel spatial analytic approach that classifies 4265 greenspaces according to twelve functional, physical characteristics. I then compare the social equity of these greenspace types using multiple operationalizations of social equity (provision, accessibility, and population pressure) throughout 4524 neighborhoods in a capital city in Australia. I find that greenspace social equity varies for each of these types. For example, results reveal that affluent households have an abundance of amenity rich greenspaces and few amenity poor ones. Further, by comparing across multiple social equity operationalizations, I find that affluent households may have a deficit of the amenity poor greenspace type, but live closer to this type. These findings confirm that employing a greenspace typology and multiple social equity operationalizations can deepen our understanding of the association between social equity and greenspace provision. This spatial analytic approach is both adaptable for examining other urban land use types, and portable to other urban contexts, and can aid urban planners, researchers, and policy makers to understand how to improve the social equity of publicly beneficial greenspace types.  相似文献   
18.
Empirical work on the relationship between environmental stress and human migration has blossomed over the last 10 years. While such work has provided important insights into this relationship, there has been, to date, limited effort expended on generating a generalisable framework for apprehending such interactions. This paper seeks to address this deficit. Based on semi-structured interviews in two sending and four receiving areas in northern Ethiopia, it explores dominant mobility narratives among populations whose livelihoods are exposed to a range of environmental stresses. Analysis of these narratives corroborates findings from other empirical studies on the subject, highlighting how the impact of environmental stress on human mobility can only be understood within the context in which it occurs. To this end the paper attempts to generate a typology of interactions between environmental and non-environmental factors shaping mobility. The typology is based on four effects: additive, enabling, vulnerability and barrier effects. It is thought to provide a generalisable conceptual language which is capable of describing the role of environmental stress in mobility decisions and thereby offering a systematic means for thinking through the processes by which environmental stress impacts upon mobility. While the framework is hypothesised to be suitably generalisable to account for other contexts and other environmental stresses, this still needs to be tested. In addition it is acknowledged that the framework suffers from some major limitations. Most notable is reliance on a conceptually false distinction between environmental and non-environmental factors, and the inability to account for the non-environmental features which shape perceptions of migration.  相似文献   
19.
Australia's large regional cities and towns display a wide variation in their adjustment to the socio-economic transitions that have occurred over the past decade. In terms of socio-economic advantage and disadvantage, these changes, often associated with globalisation, wider economic and technological restructuring, the changing demographics of the population and shifts in public policy, are not evenly dispersed across non-metropolitan regions. Such outcomes have been discussed across a variety of academic disciplines using a variety of data and methods, and the research undertaken has provided a useful grounding for contemporary studies both theoretically and methodologically. Analysis of new data provides an opportunity to extend and update our understanding. This paper presents an analysis of secondary data aimed at analysing non-metropolitan cities, towns and regions based on differential levels of socio-economic performance. Using an alternative clustering method, this paper groups non-metropolitan cities, towns and regions according to the degree to which they share similar socio-economic and demographic outcomes. These clusters form the basis of a typology representing the range of socio-economic and demographic outcomes at the non-metropolitan level.  相似文献   
20.
Climate change impacts threaten existing development efforts and achieving future sustainability goals. To build resilience and societal preparedness towards climate change, integration of adaptation into development is being increasingly emphasized. To date, much of the adaptation literature has been theoretical, reflecting the absence of empirical data from activities on the ground. However, the Funds established under the United Nations Framework Convention on Climate Change and managed by the Global Environment Facility, the Least Developed Countries Fund, the Special Climate Change Fund and the Strategic Priority for Adaptation, have approved financing for 133 adaptation projects in 70 countries with sufficient documented experience to allow for initial categorization and evaluation. This article provides the first substantial compendium of adaptation actions identified through the allocation and disbursement of these Funds and organizes these actions into a generalized typology of adaptation activities. The information obtained sheds new insight into what adaptation is, in practice, and suggests some next steps to strengthen the empirical database. Ten types of overarching adaptation activities were identified through an analysis of 92 projects financed through these Funds. This paper analyzes these adaptation activities and compares them with theoretical constructs of adaptation typologies. We find that many of the early ideas and concepts advanced by theoreticians are consistent with results from the field. The adaptation categories that recur the most in Global Environment Facility projects are enabling and relatively inexpensive measures, such as those related to capacity building, policy reform, and planning and management. However, a rich panoply of technical actions ranging from information and communications technology, to early warning systems, to new or improved infrastructure, are also identified as common project goals. Future refinements of the costs of various adaptation actions, the mixture of technical and management options, and evaluating the efficacy of actions implemented, will be key to informing the future global adaptation agenda.  相似文献   
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