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1.

An analysis of the birds in Bangkok’s urban parks and landscapes provided guidance in designing healthy urban ecosystems. This research studied the relationships between bird diversity, park size, distance to the nearest main park, and habitat compositions in 10 urban parks in the Bangkok metropolitan area between January and August in 2013. Thirty sampling points per park were used to observe the number and species of birds in each urban park. A total of 50 bird species were found. Phutthamonthon, the largest urban park (400 ha), contained the greatest number of species (39 species), followed by Suan Luang Rama IX (80 ha and 34 species) and Wachirabenchatat (60 ha and 29 species). Moreover, the diversity index (H′) was highest in Phuttamonthon (1.17), followed by Thawiwanarom (1.08), and Wachirabenchatat (1.04). Larger urban parks and parks closer to the largest urban park had higher species richness than smaller parks and parks further from the largest urban park. The large parks contain higher habitat compositions than small parks. These findings can be applied to future urban ecosystem planning to combine the importance of park size (island size, and its proximity to a large park) and its arrangement, including features such as wetland, forest, buildings and grassland; and provide basic advice for future urban park design, as well as re-design of current urban parks.

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2.
《Journal of Socio》2006,35(2):180-196
This paper considers the allocation of labour on the French and British markets, using objective wage and subjective satisfaction data. We show that, in some sectors, workers enjoy both higher wages and higher job satisfaction. We argue that this reflects labour market wage rents. Perhaps surprisingly, wage rents are typical of the British public sector and permanent contracts, but not of their French counterparts. In France, such rents are found in full-time, rather than part-time jobs. Hence, the data provide little support for the usual a priori that the French labour market is structured along insider–outsider model lines, whereby wage rents are captured by the insiders of the public sector to the detriment of the private sector. However, they do suggest that part-time employment is involuntary to a far greater extent in France than in Great Britain.  相似文献   

3.
The study investigates how the degree of exchange rate management conditions the relationship between seigniorage and governments’ natural resource revenues using a sample of 140 countries over the period from 1971 to 2012. It also disaggregates natural resource revenues to investigate if this relationship holds across the various types of natural resources. The main approach is to estimate dynamic panel data interaction models. The study finds that under exchange rate regimes characterized as fixed or of limited flexibility an increase in natural resource rents is associated with an increase in seigniorage. Under crawling currency bands and managed floating, an increase in natural resource rents has little association with seigniorage. Under exchange rate regimes permitting greater exchange rate flexibility, greater natural resource rents allow less reliance on seigniorage. Additionally, the direct relationship between natural resource rents and seigniorage is driven mostly by oil and natural gas.  相似文献   

4.
Abstract Environmental globalization has led to the implementation of conservation efforts like the creation of protected areas that often promote the interests of core countries in poorer regions. The creation of protected areas in poor areas frequently creates tensions between human needs like food and shelter and environmental conservation. Support for such conservation efforts partially depends on expectations of benefits by those impacted. This article considers the effects of different organizational models on local expectations of benefits to be derived from protected areas. Our analysis indicates that individuals are more likely to expect that benefits of the park go to other communities or the nation as a whole than to expect direct benefits for themselves. Forms of park organization also impact these expectations. Individuals exposed to the zoned park, as opposed to a conventional, strictly protected park, were more likely to expect benefits from the park regardless of the beneficiary considered. In addition, for those exposed to the zoned park, location of residence is related to expectation that individuals will benefit themselves. However, our interviews with park residents also indicate that the expectations of individual benefits are rarely met, creating potential dissatisfaction and sometimes animosity toward the park administration.  相似文献   

5.
We studied the influence of a car park on soil and vegetation within Richmond Park, UK, before and after imposition of fenced boundaries restricted public access. Soil and vegetation samples were taken before (once) and after (twice) access restrictions were enforced. The over-riding trend in all the data was for soil adjacent to the car park to be less acidic and more fertile than pristine local soils, accompanied by a more eutrophic grassland community (Lolium perenne/Trifolium repens, compared with Agrostis/Festuca grassland away from the car park). The chemical influence of the car park extended at least 50 m from its boundary. A common acidophilic collembole Folsomia quadrioculata was replaced by Cryptopygus thermophilus adjacent to the car park. There was little evidence from the vegetation data that car park closure benefitted the ecosystem, but chemical data showed signs of progressive recovery in the 2 years following restrictions. Possible explanations for the car park's influence on the local landscape are suggested to include calcareous chippings and canine faecal deposits.  相似文献   

6.
This paper relates the growth of relative wages of government scientists and other federal employees to the growth of regulation during the 1970s. A theoretical model of bureaucracy provides a linkage to data that suggest that rents were generated during the period of analysis and that at least part of those rents were paid to specialized factors in government. The opinions expressed are those of the author and do not necessarily reflect the opinions of the Commission, Commissioners, or staff of the FTC.  相似文献   

7.
8.
This paper discusses the impact of central government's rent restructuring policy on social housing in rural areas in England. It examines the effect that restructuring will have on the rents set by social landlords in a set of case study areas then considers some of the likely impacts on affordability and on new investment in rural social housing. One of the primary aims of rent restructuring policy is to reduce unjustifiable differences between the rents of similar dwellings in the local authority and Registered Social Landlord sectors locally. This aim seems likely to be achieved. In doing so, it is likely that affordability will be reduced in the local authority sector but enhanced for tenants of some RSLs. However, the reduction in real RSL rents that improve affordability may further constrain RSLs’ ability to invest in new social housing in rural areas. The paper concludes that rent restructuring by itself will not materially improve the housing prospects of the less well off in rural areas.  相似文献   

9.
Blue Shield plans often are granted regulatory advantages by the states in which they operate. Run efficiently, such not-for-profit firms should use these lower costs to eliminate their less advantaged rivals, the commercial insurers. However, these higher-cost commercial providers have been able to offer insurance coverage at prices competitive with the Blues, as evidenced by the fact that Blue plans have, on average, less than 50 percent market share. Similar prices with lower overall costs implies that economic rents are being earned, rents which a not-for-profit firm cannot distribute to owners. In this paper we argue that when there are competing goals among the groups controlling the Blue Shield plans, the different possible "uses" of the regulatory advantage become endogenously determined, necessitating the use of simultaneous equation estimation. Testing this model we find the major effect of doctor-control of Blue Shield plans is to raise doctors' fees while lowering the amount of rents captured by both consumers and administrators.  相似文献   

10.
Plant diversity and composition in urban parks is determined by socio-economics, environmental, and ecological drivers. These drivers give rise to urban spaces with unique compositions of flora, consisting of planted and spontaneous species. The present study aimed to determine the contribution of native and exotic species in urban parks of a Latin American city, and to assess the related role of park area, age and socio-economic status. We also evaluated administration type (public or private) and the effect of environmental factors on plant richness. We hypothesized that the composition of park vegetation differs according to urban-rural gradient. To determine flora composition, two transects (100 m long by 1–3 m wide) per park were selected in 49 parks. In each of these, we identified all the vascular plants found (woody and herbs, planted and spontaneous), which were then classified as native or exotic. We conducted ANCOVAs in order to determine the effect of five independent variables and one factor, on native and exotic plant richness. Of 550 recorded species, 16.2% were native and 83.8% exotic. Number of plant species per park varied between 42 and 146. The parks are known urban habitats containing the highest planted and spontaneously occurring exotic diversity in the city of Santiago, contrasting with other types of habitats. Likewise, parks in Santiago are habitats with low levels of planted and spontaneously occurring native diversity, compared to the parks of Europe, America North and Asia. Ours results show that park area and age affected native plant richness, while exotic plant richness was determined only by park age. We rejected all other possible drivers. Finally, according to the low frequency of native species, we propose that Santiago’s parks could be gradually reoriented towards ex-situ conservation of native plants.  相似文献   

11.
A consumer versus business view of regulation frequently is too simplistic. Producers as a group may also be able to obtain rents from non-consumer surplus sources, and therefore may have relatively strong aggregate incentives to organize and seek favorable regulation as compared to consumers' incentives to avoid such regulation. This occurs in an increasing cost industry where producers purchase inputs whose supply curves are not infinitely elastic. The rents obtained by producers through regulatorily initiated output restrictions then include transfers from resource suppliers as well as from consumers, and exceed the potential losses consumers face.  相似文献   

12.
ALLOCATION OF GOODS BY LOTTERY   总被引:3,自引:0,他引:3  
Many authors have argued that lotteries are used to allocate resources because of the fairness of the mechanism. However, a number of historical examples suggest otherwise. Participation fees are almost always charged and they are often discriminatory. In addition, goods (or bads) allocated by lotteries are usually not transferable. Both lottery participation fees and restrictions on transferability reduce rent-seeking from speculators. Each feature increases the rents to the primary user groups relative to the rents attainable from alternative mechanisms such as auctions, queues, or merit allocations.  相似文献   

13.
This research responds to calls from within the field of urban ecology to explicitly incorporate humanities-based research in order to achieve robust interdisciplinarity. Our research provides an example of a place-based urban ecological analysis. We use this framework to analyze over a century of park planning and development within the city of Seattle. We identify four eras of park planning that are linked by a comprehensive 100-year park plan. This case study examines how the political, cultural, and economic aspects of park planning have produced and been influenced by long-term trends and historical contingencies. This research also offers practical insights for effective contemporary urban planning, emphasizing the need for flexible and adaptive long-term plans when confronted with unpredictable events, emerging political arrangements, changing cultural priorities, and shifting fiscal climates.  相似文献   

14.
Using data on earnings and productivity for U.S. manufacturing industries from 1971 to 2001, we investigate economic rents and rising income inequalities. The results suggest that rents are most significant for managers, professionals, middle‐aged workers, and older workers. Conversely, negative rents are evident for women, Hispanics, single men, and blue‐collar workers. The underpayment of Hispanics appears to have increased while African Americans have gone from being underpaid to being overpaid. Workers with a college degree have become overpaid (i.e., “credentialism”) while “gift‐exchange” efficiency wages have declined. The marginal productivity of labor input has increased but is increasingly underpaid.  相似文献   

15.
Rapid economic development has accelerated urbanisation and biodiversity loss in Southeast Asia. Studies of urban ecology have suggested urban parks can be effective refuges for wildlife in temperate regions, but their effectiveness as refuges in rapidly urbanising tropical regions is understudied. We examined the species diversity of butterflies in urban parks in the Federal Territory of Kuala Lumpur and investigated the relationships between butterfly species richness and three park variables: i) park size, ii) distance from the central business district and iii) park age. Standardised butterfly sampling was conducted across different microhabitat types at each park: i) groves, ii) hedges, iii) flowerbeds and iv) unmanaged areas. We recorded 572 butterflies belonging to 60 species (97 % considered common) from five families. Although species richness was positively correlated with park size and age and negatively correlated with distance from the central business district; the correlations were weak and not statistically significant. However, species richness of host-specialist species was significantly positively correlated with park size and age. The highest species richness (65 % of observed species) was recorded in the unmanaged microhabitat. It is likely that both park planting scheme and the presence of early successional plants in unmanaged microhabitat led to highest butterfly species richness in parks that contained all four microhabitat types. Whether a diverse planting scheme and increased size and number of unmanaged areas in urban parks can improve the ability of parks to sustain populations of rare butterflies in the face of future urbanisation remains to be seen.  相似文献   

16.
Off-leash dog parks are very popular locations that allow pets to freely exercise and eliminate wastes in a controlled environment. Although dog park rules require that solid waste be removed by the pet’s owner, urine-borne constituents in dog-park soils have received little attention. This study focused on the soils within two small-dog, off-leash dog parks in Fargo, North Dakota (USA) with the objective to better understand the concentration and distribution of extractable NH4-N, NO3-N, PO4, soluble salts, and pH values in surface soils (0–10 cm) within these two dog parks. Concentrations of soil variables varied widely within each park and were distributed as both gradient and ‘hot-spots.’ The geospatial model types for each soil parameter were more dependent on park than on the constituents themselves. Flow accumulation was correlated with both nitrate-N and P but due to the lack of topography at these parks the flow accumulation was not helpful in describing most of the soil constituents. The results from this project indicate that location of parks, daily/annual use of parks, flow accumulation, and location of park entries may all influence the concentration and distribution of urine-borne constituents.  相似文献   

17.
Using a seven-year data set of visitation of an inner city park by the Australian white ibis, we investigated whether rain events were correlated with ibis abundance in the park. The park is associated with high levels of anthropogenic food, but relatively low levels of natural food sources. For all magnitudes of rainfall tested, ibis abundance significantly decreased after a rainfall event, although stronger responses were associated with higher rainfall, with a 46% decline in ibis abundance following rainfall events of ≥60 mm. Average ibis abundance was higher during the dry, non-breeding period than during the breeding period, and variation associated with rainfall was particularly pronounced in the non-breeding period. However, the rainfall response was still evident in both periods. Results suggest that rainfall influences the ibis distribution in urban centres either by decreasing anthropogenic food supplied to the birds, forcing the birds to relocate to forage, or increasing the amount of natural food available elsewhere, or a combination of the two. Increased rainfall intensified the response by ibis, and our results demonstrate the importance of climatic processes on the behaviour of urban birds.  相似文献   

18.
Occurrences of breeding bird species in 54 urban parks were investigated in the city of Oulu in northern Finland. Park area, human activity, habitat, and landscape structure within a 9-ha square surrounding the study park were related to the bird species richness and occurrence of individual bird species. A total of 22 species was observed. The area of the park explained 39% of the variance of species richness. Seven species (wheatear [Oenanthe oenanthe], common rosefinch [Carpodacus erythrinus], garden warbler [Sylvia borin], lesser whitethroat [Sylvia curruca], linnet [Acanthis cannabina], redpoll [Carduelis flammea], and yellowhammer [Emberiza citrinella]) were not detected in parks of >0.75 ha. Species with lower area demands occurred closer to the town center than species with greater area requirements. Ground-nesting species were poor colonizers of urban parks, whereas high numbers of nest boxes in urban parks attracted many cavity-nesting species. The willow warbler (Phylloscopus trochilus) and the magpie (Pica pica) bred more often in unmanaged than in managed parks, probably because of the greater vegetation cover in unmanaged parks. Park structure variables were entered into models for 7 of the 12 most common bird species, whereas broad scale variables were entered into models for 6 of the 12 species. The number of adjacent buildings had a negative affect on three bird species (the willow warbler, hooded crow [Corvus corone cornix], and spotted flycatcher [Muscicapa striata]). The occurrence of breeding species in urban parks depends on the size of the park, park structure, and landscape structure outside the park.  相似文献   

19.
The model of compensating differentials in regional labor and land markets was formalized by Roback (1982) . The model interprets regional differences in constant quality wages and rents as compensating firms and residents for inter‐regional differences in amenities. This paper extends the Roback model to allow for moving costs which vary among a city's residents and businesses. This modification of the model generates new interpretations of regional differences in rents and wages. The theoretical results suggest that the interpretation of inter‐city rent and wage differentials as compensating is misguided, that such differentials are inappropriate as weights in Quality of Life (QOL) comparisons, and stresses the importance of local housing market parameters in the determination of these differentials. The importance of amenities is retained, but housing supply becomes the main other determinant of regional rents. Housing supply was ignored in the literature following on Roback's initial insight. We show that interactions between amenities and housing supply will bias QOL rankings. Finally, we support the empirical importance of heterogeneous moving costs by demonstrating the effects of exogenous supply constraints on local housing prices. (JEL R31)  相似文献   

20.
Lee  Jin-Min  Gan  Jing-Ye  Yule  Catherine Mary 《Urban Ecosystems》2019,22(1):149-159

Urbanization is increasingly compromising lakes in the rapidly developing countries of tropical Southeast Asia. Greater understanding of the ecology of tropical lakes is essential in order to determine the best ways to protect and manage them. A comparison was made of the species richness, abundance and diets of Chironomidae in two forest lakes (both created by damming rivers - one in an urban forest reserve, one adjacent to an urban area) and two urban park lakes (ex- tin mine lakes) in Kuala Lumpur, Malaysia. 19 species of chironomids were recorded (10 collector-gatherers, one collector-filterer, one shredder, 3 predators and 4 predators/grazers). The most abundant species were Polypedilum leei, Tanytarsus formosanus, Zavreliella marmorata and Procladius sp.. Conductivity was highest in the urban park lakes due to pollution. Temperature was also highest in the urban park lakes due to lower riparian canopy cover and lower macrophyte abundance. Larval abundance (mostly collector-gathering Chironominae) was significantly higher in the forest lakes compared to the urban park lakes, which could be related to cleaner water and higher vegetation cover which provided more food resources (leaf litter and periphyton) and more microhabitats. Predatory tanypods were most abundant in forest lakes which also had the highest numbers of their prey (Chironominae). Four predatory species of Tanypodinae supplemented their diet with blue-green algae in two of the urban lakes. Only one collector-filterer (Corynoneura sp.) was recorded (only in the forest lakes).

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