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1.
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Sacred sites are important not only for their traditional, spiritual or religious significance, but may also potentially be valuable for biodiversity conservation in human transformed landscapes. Yet, there has been little consideration of sacred sites in urban areas in this respect. Consequently, to better understand the ecosystem service and conservation value of urban sacred sites, inventories of their floral communities are needed. We examined the richness, composition and structure of the trees and shrubs in 35 urban churchyards and cemeteries in the City of Saints (Grahamstown). The combined area of urban sacred sites (38.7 ha) represented 2.2% of the city area and 13.6% of the public green space area. Species richness of woody plants was high, albeit dominated by non-native species. Levels of similarity among sites were low, indicating the effects of individual management regimens. There was no relationship between age of the site and measured attributes of the vegetation, nor were there any significant differences in vegetation among different religious denominations. However, the basal area and number of woody plants was significantly related to site size. These results indicate the significant heterogeneity of urban sacred sites as green spaces within the urban matrix. The significance of this heterogeneity in providing ecosystem services to users of sacred sites and the broader urban communities requires further investigation.  相似文献   

3.
There is a need to establish permanent vegetation plots to study vegetation dynamics in urban and suburban landscapes. The construction and installation of a simple and inexpensive below-ground marker suitable for areas with high levels of human activity are described. These markers have been used effectively over the past decade to establish permanent plots in forests in New York City. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

4.
This Issue Brief provides summary data on the insured and uninsured populations in the nation and in each state. It discusses the characteristics most closely related to an individual's health insurance status. Based on EBRI estimates from the March 2001 Current Population Survey (CPS), it represents 2000 data--the most recent available. Between 1999 and 2000, the percentage of Americans with health insurance increased: 84.1 percent of nonelderly Americans were covered by some form of health insurance in 2000, up from 83.8 percent in 1999. The percentage of nonelderly Americans without health insurance coverage declined from 16.2 percent in 1999 to 15.9 percent in 2000, continuing a trend that started between 1998 and 1999. The main reason for the decline in the number of uninsured Americans was the strong economy and low unemployment. Between 1999 and 2000, the percentage of nonelderly Americans covered by employment-based health insurance increased from 66.6 percent to 67.3 percent, continuing a longer-term trend that started between 1993 and 1994. In 2000, 34.3 million Americans received health insurance from public programs, and an additional 16.1 million purchased it directly from an insurer. More than 25 million Americans participated in Medicaid or the State Children's Health Insurance Program, and 6.1 million received their health insurance through the Tricare and CHAMPVA programs and other government programs designed to provide coverage for retired military members and their families. Even though the number and percentage of uninsured declined substantially between 1998 and 2000, more than 38 million Americans remain uninsured. While an increasing percentage of Americans were being covered by employment-based health plans, this trend may not continue because of the combined re-emergence of health care cost inflation and the weak economy. As long as the economy is strong and unemployment is low, employment-based health insurance coverage will expand and the uninsured will decline gradually. However, the combination of the current weak economy and the rising cost of providing health benefits will likely result in more Americans without health insurance coverage. Should the uninsured remain unchanged and continue to represent 15.9 percent of the nonelderly population, 40 million would be uninsured by 2005. If the uninsured represented 25 percent of the population, 63 million would be uninsured in 2005 and 65 million nonelderly Americans would be uninsured by 2010.  相似文献   

5.
Urbanization threatens biodiversity, yet the number and scope of studies on urban arthropod biodiversity are relatively limited. We sampled ant communities in three urban habitats (forest remnants, community gardens, vacant lots) in Detroit and Toledo, USA, to compare species richness, abundance, and species composition. We measured 24 site characteristics to examine relationships between richness and composition and habitat patch size, vegetation, and urban features. Ant richness was higher in forests (26) than in gardens (14) and intermediate in vacant lots (20). Ant richness in gardens and vacant lots negatively correlated with abundance of an exotic ant species (Tetramorium caespitum); thus this ant may affect native ant richness in urban habitats. Ant composition differed with habitat type, and abundance was lowest in forests. Site characteristics varied with habitat type: forests were larger, had more woody plants, higher woody plant richness, more branches, and leaf litter whereas lots and gardens had more concrete and buildings. Vacant lots had taller herbaceous vegetation, and gardens had higher forb richness, density, and more bare ground. Differences in vegetation did not correlate with ant richness, but several vegetation factors (e.g. patch size, number and size of trees, leaf litter, and amount of concrete and buildings) correlated with differences in ant species composition. Additional factors relating to soil, nests, or microclimatic factors may also be important for urban ant communities. Implications for biodiversity conservation in urban ecosystems are discussed.  相似文献   

6.
Riparian areas in Arizona are being encroached upon by urban developments. This study investigated the impacts of different urban housing densities on riparian vegetation structure along ephemeral streams. Nine sites representing three levels of housing density were selected within the town of Marana, located in southeast Arizona. The housing densities were categorized as high (7–8 houses ha?1), moderate (2.5–4.5 houses ha?1), and low (< 1.5 houses ha?1). Each treatment had three replications. The urban developments were relatively young (less than 15 years). No significant differences were found among the treatments for the tree variables (density, height, mean canopy volume and total canopy volume) or the herbaceous vegetation variables (species richness, percentage of introduced species and percentage of ground cover). However, the shrub variables (mean density, mean height, mean canopy volume, total canopy volume and species richness) showed some significant differences. Shrub density and species richness was significantly greater adjacent to ephemeral channels than just three meters upland. In addition, whitethorn acacia shrubs were significantly taller and larger adjacent to the stream channels in the high and moderate housing density sites than in the low housing density sites. Creosote shrubs showed the opposite trend. Increased runoff in the more heavily urbanized streams may have promoted the growth of the facultative riparian species (whitethorn acacia) but not the non-riparian species (creosote). Overall, in these young developments, vegetation was resilient across the levels of urbanization explored in the study.  相似文献   

7.
City-wide relationships between green spaces,urban land use and topography   总被引:1,自引:1,他引:0  
The growing proportion of human populations living in urban areas, and consequent trends of increasing urban expansion and densification fuel a need to understand how urban form and land use affect environmental quality, including the availability of urban green spaces. Here we use Sheffield as a case study of city-wide relationships between urban green space extent, quality (vegetation cover and tree-cover), and gradients in urban form and topography. The total area of buildings and length of the road network are equally strong negative predictors of extent of green space, while the former predictor is a more important negative influence upon green space quality. Elevation positively influences extent of green space but negatively influences tree-cover. In contrast, slope of terrain positively influences green space quality and is the best predictor of tree-cover. Overall housing density is a more important negative predictor of extent of green space and tree-cover than the densities of individual housing types. Nevertheless, the latter are more important influences upon levels of vegetation cover. Threshold effects of densities of different housing types suggest opportunities for optimising green space quality, with implications for housing policy. Variation in ecological quality of green space may partly reflect different historical intensities of industrial activity.  相似文献   

8.
Although mobility investigations in urban areas indicate an overwhelming desire of older persons to age in place, such studies in rural areas are scarce. This study of 198 rural residents assesses the differences between elderly and younger respondents for socio-demographic and housing characteristics, as well as housing attitudes. Findings indicate rural elderly prefer to remain in their present home and are significantly different from their younger counterparts in socio-demographic characteristics. Recommendations are made for planned housing and for services to assist aging in place.  相似文献   

9.
Variation in densities of native and exotic urban-adapted birds across suburban habitats may reveal levels of adaptation that predict vulnerability to habitat modification over time. We investigated the densities of the eight most common exotic and native birds in a southern hemisphere city across suburbs of varying housing density, vegetative cover and garden vegetation characteristics to determine whether avian population densities are maintained across variations in habitat structure that mirror current temporal trends in land use and landscaping/gardening preferences. We also tested whether densities of birds in residential areas bordering undeveloped patches were higher due to spill-over from patches. Densities of all four native species were highest in undeveloped patches and these species were largely absent from high density housing areas. While densities of two exotic species (blackbird, song thrush) were slightly higher in suburbs with greater vegetation complexity, they were still present in higher density housing suburbs in significant numbers. Common starlings were similarly abundant across all residential habitats and house sparrow density increased in higher density housing areas. Blackbirds appeared least vulnerable to housing densification and landscaping and gardening trends because they were abundant across all habitats, including undeveloped patches. Densities of native birds were higher in residential areas bordering undeveloped patches indicating spill-over was occurring and emphasising the role that patches could play in boosting city-wide native bird abundances. Native birds are vulnerable to reductions in garden size and vegetation complexity that should have little or positive effects on populations of common exotic species.  相似文献   

10.
Retirement village living is a growing housing option for older people. Research to date has focused primarily on the social milieu of the village with limited attention to the legal and financial obligations associated with this form of specialized seniors' housing. Using data from a survey of 312 Australian residents, this article suggests while residents place financial and legal obligations at the forefront when considering relocation and during residency, there is variability in professional advice and constraints on choices when needs and capacities change. The distinctive obligations associated with retirement village living require greater attention to ensure an informed lifestyle decision.  相似文献   

11.
This Issue Brief provides historic data through 2006 on the number and percentage of nonelderly individuals with and without health insurance. Based on EBRI estimates from the U.S. Census Bureau's March 2007 Current Population Survey (CPS), it reflects 2006 data. It also discusses trends in coverage for the 1994-2006 period and highlights characteristics that typically indicate whether an individual is insured. HEALTH COVERAGE CONTINUES DECLINE: The percentage of the nonelderly population (under age 65) with health insurance coverage continued to decline, reaching to a post-1994 low of 82.1 percent in 2006. Declines in health insurance coverage have been recorded in all but four years since 1994, when 36.5 million nonelderly individuals were uninsured; in 2006, the uninsured population was 46.5 million. EMPLOYMENT-BASED COVERAGE REMAINS DOMINANT SOURCE OF HEALTH COVERAGE: Employment-based health benefits remain by far the most common form of health coverage in the United States, consistently covering 60-70 percent of nonelderly individuals. In 2006, 62.2 percent of the nonelderly population had employment-based health benefits, as compared with 64.4 percent in 1994. Between 1994 and 2000, the percentage of the nonelderly population with employment-based coverage expanded. Since 2000, the percentage has declined. PUBLIC PROGRAM COVERAGE IS STABLE: Public-sector health coverage was slightly lower as a percentage of the population in 2006, accounting for 17.5 percent of the nonelderly population. The decline was due to a drop in the percentage of the population covered by the Tricare/CHAMPVA program. Enrollment in Medicaid and the State Children's Health Insurance Program increased, reaching 34.9 million in 2006, and covering 13.4 percent of the nonelderly population, which is significantly above the 10.5 percent level of 1999, but not far above the 12.7 percent level of 1994. INDIVIDUAL COVERAGE STABLE: Individually purchased health coverage was unchanged in 2006 and has basically hovered in the high 6 and low 7 percent range since 1994. PRIVATE- VS. PUBLIC-COVERAGE TRENDS REVERSING: Health insurance coverage generally has not sustained unbroken trends since 1994. There were crosscurrents: Employment-based coverage expanded significantly in the 1994-2000 period to exceed the growth in public programs. Subsequently, the dynamic reversed, as public programs expanded while employment-based coverage declined. It appears that 2005 might be the beginning of a new trend, where the erosion in employment-based coverage is not being offset by expansions in public programs. This may be due to the fact that, while unemployment is relatively low, the cost of providing health benefits continues to increase faster than inflation.  相似文献   

12.
This Issue Brief provides summary data on the insured and uninsured populations in the nation and in each state. It discusses the characteristics most closely related to an individual's health insurance status. Based on EBRI estimates from the March 2000 Current Population Survey (CPS), it represents 1999 data--the most recent available. In 1999, for the first time since at least 1987, the percentage of Americans with health insurance increased: 82.5 percent of nonelderly Americans (under age 65) were covered by some form of health insurance, up from 81.6 percent in 1998. The percentage of nonelderly Americans without health insurance coverage declined from 18.4 percent in 1998 to 17.5 percent in 1999. The main reason for the decline in the number of uninsured Americans is the strong economy and low unemployment. Between 1998 and 1999, the percentage of nonelderly Americans covered by employment-based health insurance increased from 64.9 percent to 65.8 percent, continuing a longer-term trend that started between 1993 and 1994. In 1999, 34.1 million Americans received health insurance from public programs, and an additional 15.8 million purchased it directly from an insurer. Twenty-five million Americans participated in the Medicaid program, and 6.5 million received their health insurance through the Tricare and CHAMPVA programs and other government programs designed to provide coverage for retired military members and their families. Despite expansions in the State Children's Health Insurance Program (S-CHIP), public health insurance coverage did not increase overall between 1998 and 1999. The percentage of nonelderly Americans covered by Medicaid and other government-sponsored health insurance coverage did not change between 1998 and 1999, though some children benefited from expansions in government-funded programs. The percentage of children in families just above the poverty level without health insurance coverage declined dramatically, from 27.2 percent uninsured in 1998 to 19.7 percent uninsured in 1999. Some of the decline can be attributed to expansions in Medicaid and S-CHIP, but it appears that expansions in employment-based health insurance and individually purchased coverage had an even larger effect than expansion of S-CHIP. Even though the number and percentage of uninsured declined substantially between 1998 and 1999, more than 42 million Americans remain uninsured. As long as the economy is strong and unemployment is low, employment-based health insurance coverage will expand and the uninsured will decline gradually. If the economy continues to soften or comes close to a recession, the number of uninsured would easily and quickly start to increase again as unemployment rises. Should a severe downturn in the economy occur, causing the uninsured to represent 25 percent of the nonelderly population, 63 million Americans would be uninsured.  相似文献   

13.
This study investigates the impact of the Personal Responsibility and Work Opportunity Reconciliation Act and the Illegal Immigration Reform and Immigrant Responsibility Act, both passed in 1996, on the use of health‐care services in immigrant communities in five Texas counties. The study presents findings of interviews with public agency officials, directors of community‐based organizations, and members of 500 households during two research phases, 1997–1998 and 1998–1999. In the household sample, 20 percent of U.S. citizens and 30 percent of legal permanent residents who reported having received Medicaid during the five years before they were interviewed also reported losing the coverage during the past year. Some lost coverage because of welfare reform restrictions on noncitizen eligibility or because of changes in income or household size, but many eligible immigrants also withdrew from Medicaid “voluntarily.”  相似文献   

14.
There are a variety of land use types in urbanized areas that may have different effects on the ecological characteristics of patches of natural vegetation. In particular, residential housing and industrial land-use may have different effects on adjacent forest communities. We tested this hypothesis by examining the vegetation of forested wetlands in a densely urban region, northeastern New Jersey. Wetlands embedded in industrial areas were much less invaded by exotic plant species than were wetlands embedded in residential areas, as reflected in the number of exotic species, the fraction of the total flora that was exotic, and their frequencies of occurrence. Few other structural characteristics of the vegetation differed between the two types of urban areas. We suggest that the management of land adjacent to forest edges may explain this surprising result. The low rate of invasion of wetlands within industrial areas suggests they could have high conservation value in urban ecosystems.  相似文献   

15.
In the late 1980s, the Korean government initiated the “Two Million Home Construction Plan” to tackle severe shortages in housing and soaring housing prices. Five new towns (Bundang, Ilsan, Pyeongchon, Sanbon, and Joongdong) were planned around the city of Seoul. By the mid-1990s the residential areas in the five new towns were mostly developed. However, their commercial areas have remained underdeveloped and as a consequence, the new towns are believed to have become bedroom communities.This paper assesses self-containment status of the new towns by analyzing non-working trip patterns in the five new town areas. A survey conducted on non-working trip patterns of the residents in the five new towns and the nearby areas (to shop for groceries, clothing, electronics/jewelry, leisure/entertainment, and to access medical services) reveals that Bundang's commercial dependency upon the city of Seoul has been reduced significantly over the past 5 years (from 1995 to 2000). The survey results on non-working trip patterns of the residents in the five new towns and nearby residential areas in the Seoul Metropolitan Area indicate that the five new towns have been growing as suburban centers in the region in terms of retail attractions, even though they are still maintaining a high dependency on Seoul in terms of working commutes.These observations provide some new indications about self-containment arguments relevant to new town planning. The new towns are currently maintaining a decent degree of self-containment in terms of non-working trip, which has been an important aspect absent in self-containment arguments. In addition, the appeal of self-containment in non-working activities is growing in a dynamic sense. Observations on the dynamic process of the new town developments in Korea demonstrate that the self-containment can be established but through a long taking cumulative and stepwise process rather than immediately by planning.  相似文献   

16.
Urban development either eliminates, or severely fragments, native vegetation, and therefore alters the distribution and abundance of species that depend on it for habitat. We assessed the impact of urban development on bird communities at 121 sites in and around Perth, Western Australia. Based on data from community surveys, at least 83 % of 65 landbirds were found to be dependent, in some way, on the presence of native vegetation. For three groups of species defined by specific patterns of habitat use (bushland birds), there were sufficient data to show that species occurrences declined as the landscape changed from variegated to fragmented to relictual, according to the percentage of vegetation cover remaining. For three other groups (urban birds) species occurrences were either unrelated to the amount of vegetation cover, or increased as vegetation cover declined. In order to maximise the chances of retaining avian diversity when planning for broad-scale changes in land-use (i.e. clearing native vegetation for housing or industrial development), land planners should aim for a mosaic of variegated urban landscapes (>60 % vegetation retention) set amongst the fragmented and relictual urban landscapes (<60 % vegetation retention) that are characteristic of most cities and their suburbs. Management actions for conserving remnant biota within fragmented urban landscapes should concentrate on maintaining the integrity and quality of remnant native vegetation, and aim at building awareness among the general public of the conservation value of remnant native vegetation.  相似文献   

17.
LATEST CENSUS DATA: This Issue Brief provides historical data through 2010 on the number and percentage of nonelderly individuals with and without health insurance. Based on EBRI estimates from the U.S. Census Bureau's March 2011 Current Population Survey (CPS), it reflects 2010 data. It also discusses trends in coverage for the 1994-2010 period and highlights characteristics that typically indicate whether an individual is insured. HEALTH COVERAGE RATE CONTINUES TO DECREASE, UNINSURED INCREASE: The percentage of the nonelderly population (under age 65) with health insurance coverage decreased to 81.5 percent in 2010. Increases in health insurance coverage have been recorded in only three years since 1994, when 36.5 million nonelderly individuals were uninsured. The percentage of nonelderly individuals without health insurance coverage was 18.5 percent in 2010, up from 18.3 percent in 2009, and its highest level during the 1994-2010 period. EMPLOYMENT-BASED COVERAGE REMAINS DOMINANT SOURCE OF HEALTH COVERAGE, BUT CONTINUES TO ERODE: Employment-based health benefits remain the most common form of health coverage in the United States. In 2010, 58.7 percent of the nonelderly population had employment-based health benefits, down from 69.3 percent in 2000. SHIFTING COMPOSITION OF EMPLOYMENT-BASED COVERAGE: Between 2007 and 2010, the percentage of individuals under age 65 with employment-based coverage in their own name has dropped. In 2007, 54.2 percent had coverage in their own name. By 2010, it was down to 51.5 percent. Dependent coverage during this time period fell slightly from 17.5 percent to 17.1 percent, and increased slightly from 16.8 percent to 17.1 percent between 2009 and 2010. PUBLIC PROGRAM COVERAGE IS GROWING: Public program health coverage expanded as a percentage of the population in 2010, accounting for 21.6 percent of the nonelderly population. Enrollment in Medicaid and the State Children's Health Insurance Program increased, reaching a combined 45 million in 2010, and covering 16.9 percent of the nonelderly population, significantly above the 10.2 percent level of 1999. INDIVIDUAL COVERAGE STABLE: Individually purchased health coverage was unchanged in 2010 and has basically hovered in the 6-7 percent range since 1994. WHAT TO EXPECT IN 2011: 2010 is the most recent year for data on sources of health coverage. Unemployment in 2011 has been about 9 percent since the beginning of the year. While down from the 2010 average of 9.6 percent, it remains high and there is a continued threat of a double-dip recession increasing it even further. As a result, the nation is likely to see continued erosion of employment-based health benefits when the data for 2011 are released in 2012. Fewer working individuals translates into fewer individuals with access to health benefits in the work place, especially after COBRA subsidies have been exhausted.  相似文献   

18.
Urbanization reduces the quantity of native vegetation and alters its local structure and regional spatial pattern. These changes cause local extirpations of bird species associated with native vegetation and increases in the abundance and number of bird species associated with human activity. We used 54–1 km2 landscapes in the Seattle, Washington, USA metropolitan area to determine (1) the relative importance of habitat quantity, structure, and pattern to bird diversity and abundance and (2) whether housing developments can be managed to mitigate the negative impacts of urbanization on forest bird diversity. In general, bird species richness was high and many native forest species were retained where urban landcover comprised less than 52% of the landscape, tree density (especially that of evergreens) remained at least 9.8 trees/ha in developments, and forest was at least 64% aggregated across the landscape. These results suggest that the quantity, structure, and pattern of forested habitat affected breeding bird diversity in urbanizing landscapes. However, habitat pattern appeared less influential than other habitat attributes when results from all community- and population-level analyses were considered. Conservation of native birds in reserves can be supplemented by managing the amount, composition, structural complexity, and—to a lesser extent—arrangement of vegetation in neighborhoods.  相似文献   

19.
The purpose of this study was to explore neighborhood resources that influence the housing satisfaction of older adults. The study included 10,146 participants from the 2009 panel of the American Housing Survey who were 65 years and older. Hierarchical regression modeling was performed to examine older adults’ perceptions of neighborhood resources and consequently the role these resources play in predicting housing satisfaction among community dwelling and residents of assisted living, controlling for age, sex, ethnicity, education, and housing maintenance. In addition, three levels of physical functioning among residents of assisted living were examined. Results showed that there were differences in housing satisfaction by residences and levels of physical functioning. Subjective evaluations of neighborhoods and the near surrounds were significant predictors of housing satisfaction. Results of the study suggest that policy makers and housing professionals need to continue to consider the role of supportive neighborhoods and social environments in promoting successful aging particularly for frail older adults.  相似文献   

20.
Rural gentrification and linked migration in the United States   总被引:2,自引:0,他引:2  
Although gentrification is a process commonly associated with urban landscapes, rural areas in advanced economies have also experienced gentrification over the past two decades. Largely based on case study approaches, the Rural Studies literature describes transformations in the housing market, changed cultural attitudes toward the environment, political conflicts surrounding land-use planning, and heightened class polarization as outcomes of rural gentrification. The analysis in this paper extends our understandings of rural gentrification in two fundamental ways. First, drawing on US census data from 1990 and 2000, the paper systematically examines gentrification in nonmetropolitan counties across the United States and develops a methodology for identifying areas with similarly strong evidence of gentrification. The second section of the analysis compares the geographic distribution and socioeconomic change in gentrifying counties with the rest of nonmetropolitan America emphasizing the changes in the baby boomer and Latino populations. In so doing, the analysis opens up new possibilities for comparative analysis of gentrification both between and within countries, connects our understandings of rural gentrification to other processes of globalization playing out within rural space, and argues for work on rural gentrification to more explicitly integrate questions surrounding race and ethnicity alongside questions of class.  相似文献   

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