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1.
Throughout Central Europe, foxes have taken over urban areas as their habitat. In Southern Germany, these foxes are also carriers of the small fox tapeworm, which causes a serious zoonotic infection in humans. Therefore, a survey was carried out in a suburb of the city of Munich. A postal questionnaire was used to analyse the attitudes, opinions and fears of these participants towards their urban foxes and the background to these attitudes. Questionnaires were sent to all households with gardens and collected in again via the community council. Seven hundred and seventy-nine or 31% of questionnaires were returned. Only a few people are afraid of the fox itself; however, 55% are afraid of the fox tapeworm. Worming the animals is the preferred counter-measure, with 81% in favour. The majority of inhabitants are pleased to see a fox in the community and feel the animals have a right to live. People are afraid of the tapeworm either because they have children in the household or because of increased knowledge of the subject or because it has increasingly become an issue. On the basis of the results of this study, it is to be expected that radical solutions such as killing the foxes are unlikely to be accepted among the population. Worming of the foxes does, however, meet with general approval.  相似文献   
2.
Karachi is one of the most populated urban agglomerations in the world. No categorical study has yet discussed the geochemical baseline concentrations of metals in the urban soil of Karachi. The main objectives of this study were to establish geochemical baseline values and to assess the pollution status of different heavy metals. Geochemical baseline concentrations of heavy metals were estimated using the cumulative frequency distribution (CDF) curves. The estimated baseline concentrations of Pb, Cr, Cu, Zn and Fe were 56.23, 12.9, 36.31, 123.03 and 11,776 mg kg−1, respectively. The pollution status of heavy metals in urban soils was evaluated using different quantitative indices (enrichment factor–EF, Geo-accumulation Index–Igeo, and pollution index–PI). Enrichments factors of the selected heavy metals determined by using Fe as a normalizer showed that metal contamination was the product of anthropogenic activities. The urban soils of Karachi were found to have a moderate to moderately severe enrichment with Pb, whereas Cr and Cu has moderate and Zn has minor enrichment. Igeo results indicated moderate soil contamination by Pb at some of the sampling locations. PI for Pb, Cr, Cu and Zn was found in the range of 0.04–3.42, 0.19–1.55, 0.27–2.45 and 0.32–1.57, respectively. Large variations in PI values of Pb revealed that soil in those areas of the city which are influenced by intensive anthropogenic activities have exceptionally high concentrations of Pb. The findings of this study would contribute to the environmental database of the soil of the region and would also facilitate both at the local and the international scales, in a more accurate global environmental monitoring, which will eventually facilitate the development of management and remediation strategies for heavy metal contaminated urban soil.  相似文献   
3.
Cities and urbanized regions are complex, dynamic, and highly integrated systems linking social, ecological, and technical infrastructure domains in ways that create deep challenges for good governance, policymaking, and planning. The combination of impacts from climate change in cities, air pollution, rapid population growth, multiple sources of development pressure and overall urban system complexity make it difficult for decision-makers to develop and guide development trajectories along more livable, equitable, and at the same time, more resilient pathways. Advancing urban sustainability and resilience agendas requires expanding the scope of inter- and trans-disciplinarity approaches, moving beyond the historically separate social–ecological and socio-technical approaches to jointly study social–ecological–technical infrastructure systems in cities. We take urban complexity as a given and suggest that in both research and practice we need to better capture and understand feedbacks, interdependencies, and non-linearities which create uncertainties and challenge the efficacy of governance practices to achieve normative goals for society. Here, we explore new methods, tools, and approaches to advance our understanding of urban system complexity through a series of journal special issue articles that examine urban structure–function relationships, urban sustainability transitions, green space availability, social–ecological memory, functional traits, and urban land use scenarios.  相似文献   
4.
Rapid urbanization in major cities has adversely affected avian biodiversity in both developed and developing countries. Due to over-urbanization and little regard for nature conservation, such cities are usually characterized by poor biodiversity. In contrast to central business district areas, suburbs may support greater levels of biodiversity through an increase in green areas. We examined urban bird species richness, abundance, and composition in Klang Valley, Peninsular Malaysia. We surveyed 141 points for passerines across 80 parks grouped into two different urban zones, namely central business districts and suburbs. Our results revealed that bird richness did not differ significantly (p = 0.994) between central business districts and the suburbs. We found that the abundances of birds were significantly greater in the suburbs than in central business districts. However, species composition was similar between the central business districts and suburbs. We also found that bird richness increased significantly with an increase in size of green areas and park areas, as well as the number of woody trees in both zones. Evidence from this study suggests that creating urban parks and gardens, coupled with tree planting in central business districts, is able to support greater biodiversity, at least for birds in cities similar to those found in the suburbs.  相似文献   
5.
6.
Attributive recognition model of coalmining-based cities ecosystem classification is developed in terms of attributive mathematical theory. Based on the analysis of main causes of coalmining-based cities ecosystem, the city vitality, city structure strength, city resilience ability, service functions and health status are chosen as the criterion indicators of coalmining-based cities ecosystem classification; the attributive measurement functions are constructed to compute the attributive measurement of single indicator and multi-indicator; and the synthetic attributive measurement is calculated by the AHP; the health classification of cities ecosystem are recognized by the confidence criterion. An empirical analysis is made by the proposed model and method, the synthetic evaluation results are better than fuzzy comprehensive evaluation method which validates the proposed model feasible, effective and reliable in coalmining-based cities ecosystem classification. As attributive recognition theory can success fully resolve certain issues with a number of fuzzy attribution in comprehensive evaluation, its confidence criterion is established on the basis of the ordered evaluation sets, consequently it will make the evaluation results more reliable.  相似文献   
7.
Long-term assessments of species assemblages are valuable tools for detecting species ecological preferences and their dispersal tracks, as well as for assessing the possible effects of alien species on native communities. Here we report a 50-year-long study on population dynamics of the four species of land flatworms (Platyhelminthes, Tricladida, Terricola) that have colonized or become extinct in a 70-year-old Atlantic Forest regrowth remnant through the period 1955–2006. On the one hand, the two initially most abundant species, which are native to the study site, Notogynaphallia ernesti and Geoplana multicolor have declined over decades and at present do not exist in the forest remnant. The extinction of these species is most likely related with their preference for open vegetation areas, which presently do not exist in the forest remnant. On the other hand, the neotropical Geoplaninae 1 and the exotic Endeavouria septemlineata were detected in the forest only very recently. The long-term study allowed us to conclude that Geoplaninae 1 was introduced into the study area, although it is only known from the study site. Endeavouria septemlineata, an active predator of the exotic giant African snail, is originally known from Hawaii. This land flatworm species was observed repeatedly in Brazilian anthropogenic areas, and this is the first report of the species in relatively well preserved native forest, which may be evidence of an ongoing adaptive process. Monitoring of its geographic spread and its ecological role would be a good practice for preventing potential damaging effects, since it also feeds on native mollusk fauna, as we observed in lab conditions. Júlio Pedroni: Granted by CNPQ–Brazil.  相似文献   
8.
As a factor associated with urban management and planning, urban development intensity (UDI) could in fact form the basis for a new rationale in coordinating urban sustainable development and reducing CO2 emissions. However, existing literature engaging in the task of quantifying the impacts of urban development intensity on CO2 emissions is limited. Therefore, the goal of this study is to quantify the relationship between urban development intensity and CO2 emissions for a panel made up of the five major cities in China (Beijing, Shanghai, Tianjin, Chongqing and Guangzhou) using time series data from 1995 to 2011. Firstly, this study calculated CO2 emissions for the five selected cities and presented a comprehensive index system for the assessment of the level of urban development intensity based on six aspects (land-use intensity, economic intensity, population intensity, infrastructure intensity, public service intensity and eco-environmental intensity) using locally important socioeconomic variables. Panel data analysis was subsequently utilised in order to quantify the relationships between urban development intensity and CO2 emissions. The empirical results of the study indicate that factors such as land-use intensity, economic intensity, population intensity, infrastructure intensity and public service intensity exert a positive influence on CO2 emissions. Further, the estimated coefficients suggest that land-use intensity is the most important factor in relation to CO2 emissions. Conversely, eco-environmental intensity was identified as having a major inhibitory effect on CO2 emission levels. The findings of this study hold important implications for both academics and practitioners, indicating that, on the path towards developing low-carbon cities in China, the effects of urban development intensity must be taken into consideration.  相似文献   
9.
李膨利   《生物信息学》2019,26(5):18-23
城市热岛(UHI)不仅直接关系到城市人居环境质量和居民健康状况,同时还对城市能源消耗、生态系统过程演变、生物物候以及城市经济可持续发展有着深远的影响。以北京市朝阳区2002—2017年夏季4期Landsat系列遥感影像为数据,采用大气反演法,对15年间朝阳区城市地表温度(LST)时空变化进行分析,发现15年间朝阳区城市热岛比例指数上升迅速,热岛效应逐年加剧。进一步研究表明,城市地表温度与归一化植被指数(NDVI)及归一化建筑指数(NDBI)密切相关:地表温度与NDBI正相关,NDBI指数每升高0.1,地表升温0.79~2.37°C;与NDVI指数负相关,NDVI指数每提高0.1,地表降温0.4~0.77°C。本研究可为城市规划建设与城市绿地营建提供科学具体的参考指导依据,并促进生态可持续发展与人居环境改善。  相似文献   
10.
Acrocarpous mosses present on stonewalls in urban areas may be used for monitoring purposes. Therefore for this investigation we selected Tortula muralis expecting that this species with an ability to colonise buildings in polluted agglomerations where other species have vanished may provide important information to monitor environmental quality. Concentrations of Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, V and Zn in T. muralis, in dust deposited on sandstone surfaces, and in the sandstones on which the moss grew were measured. T. muralis appeared to be a good bioindicator of airborne pollution which accumulated especially extremely high Cu, Fe and Zn concentrations reaching values much higher than harmful for plants. There was no relation between metal concentrations in underlying sandstones and T. ruralis. There was a relation between metal concentrations in dust and T. muralis. Cd, Co, Cr, Mn and V concentrations in T. muralis were higher than in dust. The Self-Organizing Feature Map identifying groups of sampling sites with similar concentrations of metals in mosses was able to classify the pollution level by distinguishing groups of highly, medium and less polluted sites. Once trained, SOFM can be applied in ecological investigations and could form a future basis for recognizing e.g. the type of pollution in urban environments by analysing the concentrations of elements in T. muralis.  相似文献   
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