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1.
Coastal vegetation is under increasing pressure with the expansion of urban developments, tourism, population and changing climates. This study sought to examine the effects of fragmentation on the threatened plant community, Coastal Moonah Woodland, in southern Victoria, Australia. We examined the effects on community composition of surrounding land use (urban, rural, native vegetation), remnant size and environmental attributes at three spatial scales. At larger scales, geographic and environmental attributes, such as annual rainfall and temperature, were important drivers of community composition. At finer scales, remnant size, disturbance, weed invasion, connectivity, and immediate surrounding land use impacted more on community composition. At these scales, increasing native vegetation cover in the landscape, remnant connectivity and size positively influenced community composition. If coastal development continues at the current rate, all but a few remnants of this community will be surrounded by the urban landscape. Thus, planning for the integration of these remnants in the urban landscape through long-term management plans and community involvement is essential for the survival of these remnants.  相似文献   

2.
Urban areas are increasing in number, extent, and human population density worldwide. There is potential to mitigate negative impacts of urbanization to native pond-breeding amphibians by providing habitat in both remnant natural and constructed wetlands. This study examines amphibian use of potential breeding sites in natural and constructed ponds in a large metropolitan area to investigate habitat characteristics that are associated with successful breeding. I surveyed 62 ponds over three breeding seasons in Portland, Oregon, measuring eleven habitat characteristics that may influence their successful breeding: pond depth, nitrate level, aquatic refugia, aquatic vegetation, surrounding vegetation, pond permanence, presence of fish and of introduced bullfrogs, surrounding road density and forest cover, and whether they were constructed or remnant natural ponds. Five of the six native pond-breeding species that occur in the region were regularly found breeding in city ponds. Surrounding forest cover and amount of aquatic vegetation were highly associated with breeding, indicating that preserving and planting vegetation likely benefits urban amphibians. Non-native bullfrogs were not associated with native species richness. Surprisingly, whether a pond was natural or constructed was also only weakly associated with native species breeding, and the trend was towards higher presence for all species in constructed ponds. This indicates that novel, human-dominated areas can provide habitat for these species. Consideration of habitat characteristics associated with breeding success in urban pond management will likely benefit native amphibians in these rapidly expanding landscapes.  相似文献   

3.
Vegetative characteristics of urban land covers in metropolitan Tucson   总被引:4,自引:0,他引:4  
In this study we developed a methodology that associated land cover categories to aerial photographs. We selected 4, 42-mile (10 km2) study sites within metropolitan Tucson, Arizona for our pilot study. Land uses within these sites covered the range of landscapes found within Pima County, Arizona, although not necessarily in proportions representative of the metropolitan area. We designated land cover categories within the pilot sites based on recent (March, 1990) aerial photographs and developed a geographical information system (GIS) database of these land cover categories. We measured vegetation attributes on randomly selected samples within each land cover category and classified vegetation occurring on specific land cover categories according to the Brown et al. (1979) system. Our land cover classification system was nominal with a hierarchical structure, facilitating organization and providing flexibility for adding new categories.Our results showed that although neighborhood parks contained the greatest vegetated areas within our four study plots, very low density housing (4 acres/house), rivers whose banks were partially stabilized, naturally occurring washes (with no bank stabilization), and natural open space contained the highest percentage of native vegetation. Within our four study sites, low density housing (4 acres/house), rivers with partially stabilized banks, naturally occurring washes (no bank stabilization), and natural open space land cover categories contained the most area that was covered with vegetation providing escape cover.  相似文献   

4.
Urbanization and other land cover changes have been particularly detrimental to wetlands throughout the planet. One wetland specialist that may be sensitive to land cover changes surrounding wetlands is the round-tailed muskrat (Neofiber alleni; hereafter RTM). The RTM is a wetland obligate rodent that appears to have declined over the last half century and is a species of concern in Florida, where it is a near endemic. To determine if urbanization or other land cover influenced the distribution of RTMs we took a multi-scaled approach to examine the occurrence of RTMs and their associated vegetation in North-Central Florida. We detected RTMs on 19 of 72 sample plots and used a Classification And Regression Tree (CART) to determine that dogfennel (Eupatorium capillifolium) was negatively associated with RTMs and maidencane (Panicum hemitomon) was positively associated with their occurrence on sampling plots. Examining the influence of landscape composition for 2 km surrounding our plots we found that RTM occurrence was negatively related to urban land cover. Further, we found that dogfennel increased and maidencane decreased as urbanization increased in the surrounding landscape. Our research suggests that conservation of RTMs and their associated vegetation should focus on limiting urban sprawl at least within 2 km of wetlands.  相似文献   

5.
It is argued that the abstract product attributes that consumers mention in a research setting should not be interpreted as combinations of the more concrete attributes consumers mention. Results from a laddering study show that a majority of elicited abstract product attributes are unrelated to concrete attributes. Furthermore, these unrelated abstract attributes are about different product aspects than the related abstract attributes. These findings are discussed in the light of the problem of ‘actionability', and of models for new product development.  相似文献   

6.

Actions and policies to enhance biodiversity in the urban landscape must match the spatial scale at which biodiversity responds to the management and target variables. To this end, we compare the importance and effect of different kinds of greenery cover and road-lane density on bird and butterfly species richness between two landscape scales: 50-m versus 126-m radii around point counts (equivalent to areas of 0.8 h and 5 ha, respectively). We also compared the results against those of an earlier study using 500-m walking transects with widths of 100 m (i.e., 5 ha). Road lane density was more important at the 126-m than 50-m radius for both birds and butterflies. For birds, natural vegetation or forest cover and cultivated shrub cover were also more important at 126-m radius whereas the cultivated tree canopy cover was more important at 50-m radius. Cultivated tree cover and natural vegetation or forest cover were positively associated with species richness while road lane density and cultivated shrub cover were negatively associated with species richness. The results from point counts generally corroborate the results from the transects-based study, except that the short-duration point counts performed poorly in sampling butterflies. Our results indicate that in designing urban greenery policy, the plot sizes of individual developments is an appropriate spatial scale for the stipulation of tree cover targets, while urban planners have more flexibility to allocate natural greenery at broader spatial scales.

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7.
Investigations of urbanization effects on birds have focused mainly on breeding traits expressed after the nest-building stage (e.g. first-egg date, clutch size, breeding success, and offspring characteristics). Urban studies largely ignored how and why the aspects of nest building might be associated with the degree of urbanization. As urban environments are expected to present novel environmental changes relative to rural environments, it is important to evaluate how nest-building behavior is impacted by vegetation modifications associated with urbanization. To examine nest design in a Mediterranean city environment, we allowed urban great tits (Parus major) to breed in nest boxes in areas that differed in local vegetation cover. We found that different measures of nest size or mass were not associated with vegetation cover. In particular, nests located adjacent to streets with lower vegetation cover were not smaller or lighter than nests in parks with higher vegetation cover. Nests adjacent to streets contained more pine needles than nests in parks. In addition, in nests adjacent to streets, nests from boxes attached to pine trees contained more pine needles than nests from boxes attached to other trees. We suggest that urban-related alterations in vegetation cover do not directly impose physical limits on nest size in species that are opportunistic in the selection of nesting material. However, nest composition as reflected in the use of pine needles was clearly affected by habitat type and the planted tree species present, which implies that rapid habitat change impacts nest composition. We do not exclude that urbanization might impact other aspects of nest building behaviour not covered in our study (e.g. costs of searching for nest material), and that the strengths of the associations between urbanization and nest structures might differ among study populations or species.  相似文献   

8.
Spatio-temporal analysis of urban temperature in Bandung City,Indonesia   总被引:1,自引:0,他引:1  
This study presents an evaluation of urban micro-climate about the exsistence level urban vegetation, in association with the urban temperature (surface temperature) and urban built-up area of Bandung City. The changes in urban vegetation cover, urban temperature, and urban built-up area observed using Landsat 5 TM and Landsat 7 ETM + bands were evaluated on the basis of the WDRVI (Wide Dynamic Range Vegetation Indices), NDBI (Normalized Difference Built-up Index), and SAVI (Soil-Adjusted Vegetation Index). It was found that, due to the uncontrolled urban growth and the removal of urban vegetation cover and urban green space, there was a significant increase in urban temperature, in NDBI, but a decrease in WDRVI. The maximum urban temperatures, NDBI, and the minimum values of WDRVI indices were established in 2009. Therefore the results indicate a significant effect of higher density of impervious surfaces coverage (urban built-up area) contributing significantly to the increase of urban temperature. Again the results also confirm that urban vegetation landscape coverage in the surrounding of industrial area reduced the urban temperature. Based on the results, we recommend the city government to provide more urban green space by cooperating with private land owner, in order to decrease urban temperature and create a healthier living environment for urban inhabitants.  相似文献   

9.
The simplest form of a ‘green wall’ is where self-adhering climbing plants colonise vertical surfaces, an approach that has been used on buildings for millennia (Koehler 2008). Green walls in urban areas are now well-known for their insulation and air cleaning capacities, but little is known of their value as habitats for wildlife. This paper presents preliminary findings of their value for urban birds. The abundance of birds, on 27 green walls and within the area enclosed by a semi-circle of 10 m radius immediately surrounding them, was compared with 27 walls without vegetation (bare walls) and similar surroundings. The study was carried out during the summer and winter of 2010–11 in north Staffordshire (UK). Birds exploited the green walls for various reasons (including nesting, food and shelter) but were never found on bare control walls. The roofs of buildings and the surrounding vegetation were used by birds in both regimes, but birds were more abundant in areas with green walls. The use of green walls by birds depended on the time of day, the season and whether the vegetation was evergreen or deciduous. The birds’ activity was always restricted to the upper half of the wall vegetation. Green walls and the immediate surroundings were used by some species of conservation concern in Great Britain (e.g. Passer domesticus and Sturnus vulgaris). Therefore, encouraging householders and businesses to grow vegetation up walls may be an effective way of providing a range of resources for birds in urban areas without the need for expensive additional land-take.  相似文献   

10.
Along heavily engineered urban rivers, river walls and embankments represent the most common habitat available to riparian vegetation. This paper presents the first study into river wall vegetation and the influence of wall surface materials on plant diversity. We were concerned with investigating the plant diversity of such wall habitats, assessing relationships between different wall surface materials and plant diversity, and determining whether river wall and embankment habitats along the River Thames through central London could support native riparian species alongside more typical urban wall flora. Fifteen sites along the River Thames through central London were surveyed to describe wall flora and establish relationships between plant diversity and wall materials. Walls were not species rich, but contained a mix of terrestrial and riparian species. Stone walls with surface fractures and heterogeneous wall surfaces were conducive to plant diversity at the local scale, while wall surface heterogeneity was also important at the landscape scale. Some stratification of vegetation was observed based on wall position relative to flow disturbance. The potential exists for walls to act as sites for habitat improvement and reconciliation ecology within urban rivers.  相似文献   

11.
Urban gardens may support bees by providing resources in otherwise resource-poor environments. However, it is unclear whether urban, backyard gardens with native plants will support more bees than gardens without native plants. We examined backyard gardens in northwestern Ohio to ask: 1) Does bee diversity, abundance, and community composition differ in backyard gardens with and without native plants? 2) What characteristics of backyard gardens and land cover in the surrounding landscape correlate with changes in the bee community? 3) Do bees in backyard gardens respond more strongly to local or landscape factors? We sampled bees with pan trapping, netting, and direct observation. We examined vegetation characteristics and land cover in 500 m, 1 km, and 2 km buffers surrounding each garden. Abundance of all bees, native bees, and cavity-nesting bees (but not ground-nesting bees) was greater in native plant gardens but only richness of cavity-nesting bees differed in gardens with and without native plants. Bee community composition differed in gardens with and without native plants. Overall, bee richness and abundance were positively correlated with local characteristics of backyard gardens, such as increased floral abundance, taller vegetation, more cover by woody plants, less cover by grass, and larger vegetable gardens. Differences in the amount of forest, open space, and wetlands surrounding gardens influenced abundance of cavity- and ground-nesting bees, but at different spatial scales. Thus, presence of native plants, and local and landscape characteristics might play important roles in maintaining bee diversity within urban areas.  相似文献   

12.
This article presents a study on the perception of fear related to the use of three different types of urban furniture, qualitatively evaluated based on interviews while people were using them in the city of Porto Alegre, Brazil: the bus shelter, the playground, and the gymnastic equipment. The fear related to the lack of safety of the urban space was associated with the use of the three types of products. The fear experienced by the use of the playground and the bus shelter was related to the occurrence of accidents, since both products are often unsafe and do not fulfill ergonomic parameters. The fear experienced from the use of the gymnastic equipment is related to the possibility of incorrect use of the product and the occurrence of harassment. Both ergonomics and emotion are important aspects to be considered in design, in order to make the use of social/ collective products a pleasant experience.  相似文献   

13.
The composition of the plant community in remnant patches of open grassy woodlands with an overstorey of Eucalyptus camaldulensis was investigated along an urban–rural gradient in Melbourne, Australia. The plant community showed very little difference between patches along the gradient, particularly in terms of the indigenous plant species. Average annual rainfall was the main factor contributing to patterns of indigenous plant species richness, while the level of urbanization in the surrounding landscape had a strong influence on the number of non-indigenous species recorded in the remnant plant community. Patterns of species richness were largely influenced by landscape-scale factors, while the percent cover of indigenous and non-indigenous plant species were more strongly influenced by patch scale factors. The findings of this study suggest that the plant communities investigated during this study appear to be relatively resilient to changes in the landscape associated with urbanization, but the plant community may be affected by predicted changes in average annual rainfall associated with climate change.  相似文献   

14.
A growing trend towards increased urbanization emphasizes the role of suburban parks in wildlife conservation. Spatial planning aimed at maintaining biological diversity and functionality must consider how changes at landscape and more local scales will influence the biotic structure of urban areas. From May 2006 to July 2010, bird surveys were conducted in three metropolitan parks in Cleveland, Ohio, USA. Surveys were conducted with the goal of examining the effect of vegetation structure and adjacent land cover on the distribution and species richness of breeding birds within this park system. A total of 65 species were recorded throughout the study area. Avian species richness was linked to several habitat metrics, measured at both the local and landscape scale. Generally, species richness was highest at locations characterized by moderate forest cover. The proportion of canopy cover at survey sites related negatively to species richness and the density of understory vegetation showed a positive relationship with species diversity. Despite the influence of these three metrics, sensitivity analysis indicates that the density of understory vegetation is the most significant correlate to avian diversity within this suburban park system. Management actions aimed at providing habitat for the greatest diversity of breeding songbirds within the study area should allow for moderate canopy cover while retaining or improving the structural complexity of understory vegetatation.  相似文献   

15.
《Sociological inquiry》2018,88(2):193-215
Theories about fear of crime may offer insights about the use of public shelters in disaster situations. This study focuses on fear of victimization and gendered explanations of fear of crime in public shelters during hurricane events. From surveys of 424 North Carolina residents, 179 respondents described safety concerns with staying in a public shelter. Fear of victimization was the most commonly identified safety concern in connection to anticipated shelter use, significantly more so than concerns related to sanitation or structural integrity. Female respondents more often described fear of violent and sexual crimes in public shelters, which could be explained through the sexual assault hypothesis. We draw into our analysis literature examining the relationship between fear of crime and gender as we explore the implications of the results on planning for evacuation and sheltering in disaster events. By directly addressing perceived security in public shelters, we hope to expand our understanding of an important U.S. disaster setting by bridging research between fear of crime and disaster studies.  相似文献   

16.
Nest boxes are commonly erected in managed landscapes such as backyards, golf courses and parks, attracting cavity-nesting birds to habitats they would not otherwise occupy. Although studies have shown that habitat around natural nests influences postfledging survival, this relationship has not been examined for artificial nest cavities, which humans may site at inappropriate locations. In Williamsburg, Virginia, we compared vegetation surrounding nest boxes which produced eastern bluebird fledglings that were predated by hawks within 10 days of leaving the nest to vegetation surrounding nest boxes producing surviving fledglings. We found a significant difference between PC scores for forest denseness around nest boxes that produced surviving versus predated fledglings; fledglings that survived tended to come from nest boxes with high forest and canopy cover, close trees and little grass.  相似文献   

17.
The riparian zones of urban waterways are frequently degraded by weed invasions. This study examined the effects of different levels of catchment imperviousness, as a surrogate for the extent and intensity of urbanisation, on invasive weeds and soil physical and chemical attributes. The study was conducted adjacent to waterways in the partly urbanised Georges River catchment in south western Sydney. Vegetation and soil sampling was undertaken in the riparian zone of 10 freshwater streams in non-urban (low imperviousness), peri-urban (moderate imperviousness) and urban (high imperviousness) sub-catchments. Soil samples were tested for a suite of physical and chemical properties (moisture, bulk density, organic matter, pH, salinity, phosphorus, potassium and calcium). Increased levels of sub-catchment imperviousness and urbanisation were associated with higher weed coverage and elevated soil geochemical attributes. One of the most interesting findings in this study was that urban soil calcium concentrations were over 2000 times greater than soils collected from non-urban catchments. The BIOENV procedure identified soil pH, salinity, calcium, organic matter, moisture and catchment imperviousness to be important environmental factors associated with variation in riparian vegetation. The single factor of soil pH was most highly correlated with variations in riparian vegetation. Soil pH was approximately 1.5 units higher in urban compared to non-urban riparian soils. We speculate that there is a link between urban concrete materials, urban soil and water contaminants and riparian weed invasion. We also recommend further study into the contribution of urban concrete materials on the geochemical contamination of riparian soils.  相似文献   

18.
The effects of trampling on the understorey vegetation were studied in boreal urban forests of different fertility in the greater Helsinki area, Finland. The three studied forest types in decreasing order of fertility were: 1) herb-rich heath forest, 2) mesic heath forest, and 3) sub-xeric heath forest. We inventoried the cover percentages of understorey vegetation in 40 herb-rich, 75 mesic and 40 sub-xeric biotopes located in 51 urban forests varying in size (0.6–502 ha). Cover percentages were compared to those of untrampled reference areas. In our study, trampling tolerance increased with increasing fertility of the forest type. Wear of understorey vegetation correlated positively with the number of residents (i.e. recreational pressure) around the forest patch. In general, understorey vegetation cover in all three forest types was lower than in the same forest types in untrampled reference areas. Ground layer cover in urban forests was less than half of that in reference areas. Mosses, lichens, and dwarf shrubs, especially Vaccinium vitis-idaea, proved to be sensitive to trampling and consequently decreased in cover. The cover of tree saplings, mainly Sorbus aucuparia, and some resilient herbs increased.  相似文献   

19.
This study aims to evaluate the current bus stop shelter model used in Florianópolis, Brazil, through a functional analysis--focused in the relationship between the shelter, the users and their activities--and also to analyse users' perceptions. The methodology consisted of exploratory visits, anthropometric analysis, observation and interviews. The exploratory visit intended to survey the physical characteristics of the shelter (dimensions, materials, colors, displayed information) and its position on the sidewalk. The anthropometric analysis was made to verify whether the dimensions of the shelters were adequate to users' needs. The observation provided data for the analysis of users' behavior, which involved a biomechanical study of their postures, an ownership/occupancy analysis in terms of territoriality and studies about spatial requirements of interpersonal relations (proxemics). The interviews helped to analyze how the user perceives the quality of some of the main functions of the shelter: to provide physical and psychological comfort and to display information about the public transportation system. As a result, the overall conclusion is that shelters do not meet users' needs. Recommendations are provided in order to improve physical and psychological comfort and to display relevant information about the transportation system.  相似文献   

20.
Qiu  Yanning  Chen  Bin J. W.  Song  Yanjuan  Huang  Zheng Y. X.  Wan  Li  Huang  Cheng  Liu  Maosong  Xu  Chi 《Urban Ecosystems》2016,19(2):939-948

The vertical surfaces of walls accommodate diverse plants in urban areas. Characterizing species composition and distribution of plants growing in these habitats is of great significance towards a better understanding and management of urban ecosystems. Here we focused on the City Wall of Nanjing (CWN), one of the biggest and best reserved ancient masonry city walls in the world. Through detailed field survey, we investigated species composition, richness and cover of the vascular plants on the CWN, and examined their relationships with a set of local habitat factors including aspect, position, height of the wall and ground vegetation status, using canonical correspondence analysis and multiple regression models. In total we found 67 plant species on the CWN. They are mostly widespread ruderal plants, with a conspicuously high proportion of vine species. Surprisingly, we found that the investigated habitat factors generally have weak correlations (R 2 < 10 %) with species composition, species richness and plant cover. The relationships remain weak when specified in different species groups in terms of life forms and seed dispersal traits. However, these species groups appear to have distinct responses to particular micro-habitat conditions such as light and intensity of human activities. Our results provide useful implications for protecting the walls and enhancing ecosystem services of their associated vegetation.

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