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1.
In light of the rapid urbanization of the world’s population over the past decades, there is a growing concern about the environmental impacts of urban population growth. Rural–urban migration is a particularly important component of the urbanization process in developing countries and is often considered to be detrimental to urban environmental conditions. However, few studies have explicitly examined the presumed negative impacts of in-migration on the natural environment of cities. The continuously increasing volume of rural–urban labor migration in China since the early 1980s has formed the largest population flow in world history. This study links the existing literature on population–environment and urbanization–environment interactions by empirically assessing the relationship between rural–urban migration and urban air conditions in China. A two-period (2004 and 2010) longitudinal dataset for the 113 key environmental protection cities of China was constructed based on multiple data sources. We applied the STIRPAT equation using conventional and spatial panel regression models to examine whether rural–urban migration flows were associated with air pollution in cities. Results show a strong negative association of in-migration with urban air quality even after controlling for the effects of other population, affluence, and technology factors. Findings from this research can contribute to a better understanding of the environmental consequences of rural–urban migration in China, with broader implications for sustainable development research and policies.  相似文献   

2.
Abandoning fossil fuels and increasingly relying on low-density, land-intensive renewable energy will increase demand for land, affecting current global and regional rural–urban relationships. Over the past two decades, rural–urban relationships all over the world have witnessed unprecedented changes that have rendered their boundaries blurred and have lead to the emergence of “new ruralities.” In this paper, we analyze the current profiles of electricity generation and consumption in relation to sociodemographic variables related to the use of time and land across the territory of Catalonia, Spain. Through a clustering procedure based on multivariate statistical analysis, we found that electricity consumption is related to functional specialization in the roles undertaken by different types of municipalities in the urban system. Municipality types have distinctive metabolic profiles in different sectors depending on their industrial, services or residential role. Villages’ metabolism is influenced by urban sprawl and industrial specialization, reflecting current “new ruralities.” Segregation between work activity and residence increases both overall electricity consumption and its rate (per hour) and density (per hectare) of dissipation. A sustainable spatial organization of societal activities without the use of fossil fuels or nuclear energy would require huge structural and sociodemographic changes to reduce energy demand and adapt it to regionally available renewable energy.  相似文献   

3.
The paper explores the concept of ‘sustainable place-making’ and its necessary relationships and opportunities with the emerging, broader and interdisciplinary field of sustainability science. This implies a reconsideration of the new and emerging interrelationships between economy, community and ecology as a basis for active place-making. The paper then examines the new dynamics of place-making with regard to the contested emergence of the bio-economy and the eco-economy, and the principles and place framings that lie behind these competing paradigms of spatial development. The reference point here is agri-food and urban–rural relations; and it is argued that research in these fields is in need of being contextualised critically and normatively within this dynamic, highly contested and place-making context. The analysis also holds important implications for a more critical and engaging sustainability science.  相似文献   

4.
Environmental distribution conflicts (EDCs) related to the construction and operation of waste incinerators have become commonplace in China. This article presents a detailed case study of citizen opposition to an incinerator in the village of Panguanying, Hebei Province. Drawing on in-depth fieldwork, we show how this case was notable, because it transcended the local arena to raise bigger questions about environmental justice, particularly in relation to public participation in siting decisions, after villagers exposed fraudulent public consultation in the environmental impact assessment. An informal network between villagers and urban environmental activists formed, enabling the Panguanying case to exert influence far beyond the village locality. This network was critical in creating wider public debate about uneven power and substandard public participation in siting disputes, a central feature in many Chinese EDCs. By transcending local specificities and exposing broader, systemic inadequacies, this case became instrumental in supporting “strong sustainability”.  相似文献   

5.
Sixteen existing multi-family buildings (94 apartments) in Finland and 20 (96 apartments) in Lithuania were investigated prior to their renovation in order to develop and test out a common protocol for the indoor environmental quality (IEQ) assessment, and to assess the potential for improving IEQ along with energy efficiency. Baseline data on buildings, as well as data on temperature (T), relative humidity (RH), carbon dioxide (CO2), carbon monoxide (CO), particulate matter (PM), nitrogen dioxide (NO2), formaldehyde, volatile organic compounds (VOCs), radon, and microbial content in settled dust were collected from each apartment. In addition, questionnaire data regarding housing quality and health were collected from the occupants. The results indicated that most measured IEQ parameters were within recommended limits. However, different baselines in each country were observed especially for parameters related to thermal conditions and ventilation. Different baselines were also observed for the respondents' satisfaction with their residence and indoor air quality, as well as their behavior related to indoor environment. In this paper, we present some evidence for the potential in improving IEQ along with energy efficiency in the current building stock, followed by discussion of possible IEQ indicators and development of the assessment protocol.  相似文献   

6.
To evaluate the quantities of 137Cs from past nuclear tests being transported to and deposited in Japan by naturally-occurring phenomena, the authors developed long-range transport models for 137Cs considering Asian dust. The simulation using these models backed the observed recent increase of 137Cs deposition along the coast of the Sea of Japan in early spring. For the sake of public safety, it is vital to ascertain whether an increase of radioactive deposition is caused by natural phenomena or a nuclear accident. The observations in recent years have suggested that dust and soil containing 137Cs is transported from the regions around Inner Mongolia to Japan by the wind. In this paper, using observation data from the early spring of 2002 and 2006, the authors have found good agreement between the simulations and the measurements. The simulations reproduced the entrainment of 137Cs and subsequent transport to Japan caused by strong winds associated with low pressure areas around the Inner Mongolian grasslands. The most likely cause of high-level 137Cs deposition over northern Japan during March 2002 was 137Cs associated with particles transported at low-altitude (1 km) and subjected to precipitation on the 22nd to 24th.  相似文献   

7.
ABSTRACT

As the space carrier of the construction of ecological civilization, land’s green and efficient utilization is an important guarantee for realizing national sustainable development. Based on traditional land evaluation, this paper scientifically defines the green land use, puts land as one of the production factors, and brings energy consumption, environmental pollution, etc. into the input-output system to measure the green land utilization efficiency of the urban construction land of Beijing-Tianjin-Hebei Urban Agglomeration from 2006 to 2016. The study shows that the overall efficiency variation of the urban agglomeration is related with the land and environment policies. Efficiency of 2016 is higher than that of 2006, and energy and environment are the principal factors affecting the green land use. The efficiency of each city is positively correlated with its economic development, negatively correlated with the construction land expansion. Efficiency gaps in different cities are expanding. There is positive correlation with overall weak space between cities, and the partial spatial agglomeration phenomenon appears. Therefore, the green land use efficiency could be improved by improving land utilization efficiency, coordinating economic growth of construction land utilization with environmental protection and taking feasible ways to transregional renovation of the stock ecological land utilization, etc.  相似文献   

8.
The consumption and production of food products in the municipality of Lisbon in the 1890–1900 decade is assessed with the support of historical cartography and statistical resources. For the first time, food production in a municipality in the turn to the twentieth century is accounted and simultaneously subject of a visual analysis of the land used for agriculture and of the water infrastructures that supported such uses. Agriculture occupied at least 40 % of the territory of the city, while the built environment occupied no more than 16 % of the territory. However, local production of food was far from supplying most of the citizens’ needs, and substantial food imports were needed. In this context, the municipality behaved like a heterotrophic system, highly dependent on the external supply of resources. Moreover, comparing to other European cities at the time Lisbon was facing in the end of the nineteenth century a late and slow transition from an agrarian social metabolism to an industrial one, suggesting that Lisbon was still relatively high-solar-powered as compared to other European cities at the time that were already highly fossil-fuel-powered.  相似文献   

9.
We characterized the differences in warm-season weekday and weekend aerosol conditions and cloud-to-ground (CG) flashes (1995–2008) for an 80,000 square kilometer region around Atlanta, Georgia, a city of 5.5 million in the humid subtropics of the southeastern United States. An integration of distance-based multivariate techniques (hierarchical agglomerative clustering, multiresponse permutation procedures, fuzzy kappa statistics, and Mantel tests) indicated a greater concentration of CG flash activity within a 100 km radius around Atlanta under weekday aerosol concentrations. On weekends, these effects contracted toward the city. This minimized any weekly anthropogenic cycle over the more densely populated urban center even though this location had a higher flash density, a higher percentage of days with flashes, and stronger peak currents over the course of a week compared to the surrounding region. The sharper contrasts in weekday and weekend lightning regime developed outside the perimeter of the city over nonurban land uses. Here, lightning on weekend and weekdays differed more in its density, frequency, polarity, and peak current. Across the full extent of the study region, weekday peak currents were stronger and flash days more frequent, suggesting that weekly CG lightning signals have a regional component not tied to a single city source. We integrate these findings in a conceptual model that illustrates the dependency of weekly anthropogenic weather signals on spatial and temporal extent.  相似文献   

10.
This paper investigates household preferences regarding an improved supply of electricity in rural Bangladesh, where the expansion of stable electricity is an urgent policy issue. The paper examines household preferences regarding reductions in the frequency and duration of power outages. It also examines prior notification mechanisms that do not necessarily provide an increased supply of electricity but that allow households to prepare for potential power failures. A questionnaire survey designed as a choice experiment was applied to households to elicit preferences. The econometric analysis reveals that villagers prefer a reduction in both the frequency and duration of power outages and a 1-day prior notification of power outages. There are slight disparities in preferences according to the season and the timing of improvements (e.g., summer or winter and all day or peak hours). Thus, the present study may be beneficial for policymakers when considering the provision of electricity supply improvements in rural areas in exchange for slight increases in electricity tariffs.  相似文献   

11.
China-Africa development cooperation in the rural sector has received an increased attention by researchers and policy-makers given the advantages and disadvantages of China’s contribution to the local economy. However, there is a lack of more reliable and nuanced findings to provide greater insights into the major issues concerning rural development and resource use. This paper aims to position land tenure and foreign investments linkages as a new research angle for understanding the role of land in sustainable resource use and investments. The paper provides a brief overview of China-Africa cooperation in rural development especially concerning agriculture to illustrate the neglect of critical land and resource use issues in policy and practice. The paper briefly discusses the ongoing land tenure reforms in Africa and the policy gaps to be filled through further research. It also discusses how China’s own development model, especially concerning land tenure reform, shares similar trajectories with Africa, which has important implications for the effectiveness of Chinese investments in African land. The paper concludes that there is an urgent need for lesson learning among Chinese and African policy-makers and investors towards tailoring development cooperation to more appropriate land tenure systems for sustainable resource use to the mutual benefit of Chinese and African stakeholders.  相似文献   

12.
Regional Environmental Change - Sustainable urban infrastructure transition is perhaps the biggest challenge confronting cities in the global south in a time of climate change. Fast-growing cities...  相似文献   

13.
Air (vapor and particle phase) samples were collected every 12 days at five sites near the North American Great Lakes from 1 January 2005 to 31 December 2013 as a part of the Integrated Atmospheric Deposition Network (IADN). The concentrations of 35 polybrominated diphenyl ethers (PBDEs) and eight other halogenated flame retardants were measured in each of the ~ 1,300 samples. The levels of almost all of these flame retardants, except for pentabromoethylbenzene (PBEB), hexabromobenzene (HBB), and Dechlorane Plus (DP), were significantly higher in Chicago, Cleveland, and Sturgeon Point. The concentrations of PBEB and HBB were relatively high at Eagle Harbor and Sturgeon Point, respectively, and the concentrations of DP were relatively high at Cleveland and Sturgeon Point, the two sites closest to this compound's production site. The data were analyzed using a multiple linear regression model to determine significant temporal trends in these atmospheric concentrations. The concentrations of PBDEs were decreasing at the urban sites, Chicago and Cleveland, but were generally unchanging at the remote sites, Sleeping Bear Dunes and Eagle Harbor. The concentrations of PBEB were decreasing at almost all sites except for Eagle Harbor, where the highest PBEB levels were observed. HBB concentrations were decreasing at all sites except for Sturgeon Point, where HBB levels were the highest. DP concentrations were increasing with doubling times of 3–9 years at all sites except those closest to its source (Cleveland and Sturgeon Point). The levels of 1,2-bis(2,4,6-tribromophenoxy)ethane (TBE) were unchanging at the urban sites, Chicago and Cleveland, but decreasing at the suburban and remote sites, Sturgeon Point and Eagle Harbor. The atmospheric concentrations of 2-ethylhexyl-2,3,4,5-tetrabromobenzoate (EHTBB) and bis(2-ethylhexyl)-tetrabromophthalate (BEHTBP) were increasing at almost every site with doubling times of 3–6 years.  相似文献   

14.
Hydropower developments along the main stem of the Mekong River and its tributaries cause transboundary effects within the Mekong Basin Region, which comprises parts of six countries. On the one hand, the provision of hydropower triggers economic development and helps to meet the rising energy demand of the Mekong riparian countries, especially China, Thailand, and Vietnam. On the other hand, the negative impact of dam construction, mainly altered water flow and sediment load, has severe impacts on the environment and the livelihoods of the rural Mekong population. Several discrepancies exist in the needs, demands, and challenges of upstream versus downstream countries. Against the common apprehension that downstream countries are powerlessly exposed to mainly negative impacts whereas upstream countries unilaterally benefit from hydropower, the authors argue that upstream–downstream relations are not really clear-cut. This conclusion is based on a consideration of the complex power play between Mekong riparians, with a focus on recent power trade interactions. The article investigates the consequences of hydropower dams for the Mekong region as well as the role of supranational players, such as the Mekong River Commission and the Greater Mekong Subregion Initiative, on the hydropower debate. It is not nations that are the winners or losers in the hydropower schemes in the Mekong, but rather parts of the riparian population: a few influential and powerful elites versus the large mass of rural poor.  相似文献   

15.
The Fulani pastoralists of the Western Highlands of Cameroon are a subgroup of the Fulbe, a wider pastoral group whose members are dispersed across Sub-Saharan Africa. They migrated and settled in the region in the early twentieth century at different times in migratory waves. Since arriving in the region, they have experienced different stages of transformation due to changing socioeconomic, political and ecological conditions influencing their nomadic lifestyle. The Fulani pastoralists have moved from a purely nomadic lifestyle that involved permanent seasonal migration with their herds and families to a semi-nomadic lifestyle involving return to their previous settlements at the end of each transhumance season, and they finally have adopted a more sedentary community lifestyle that involves only the seasonal movement of herdsmen and their cattle during dry periods. This pastoralist transformation process was motivated by the hospitality of native farming communities, the British colonial administration and postcolonial government of Cameroon, population growth and environmental degradation in the Western Highlands of grazing and cultivable land. This transformation has been beneficial to both pastoralists and native farming groups by improving local community development through increased agro-pastoral production and the realization of communal development projects in education and non-agro-pastoral economic activities. Several challenges have confronted this Fulani pastoralist transformation and its community development in the Western Highlands of Cameroon: landuse competition involving farmer–herder conflicts and inter-tribal wars; climate change, including rainfall variability; and environmental degradation including the disappearance of agro-pastoral lands. This paper, based on field research, investigates the various approaches, benefits and challenges involved in Fulani pastoralists’ settlement transformation in the Western Highlands of Cameroon.  相似文献   

16.
Environment, Development and Sustainability - The human pressure on nature makes it imperative understanding how environmental issues can influence the world view of society. The aim of the current...  相似文献   

17.
Spatio-temporal variations in the technetium-99 content of Fucus serratus samples from the French coast of the English Channel were studied between 1982 and 1984 using various sampling strategies. The lack of constancy in measurements from within the seaweed zone of the same station is revealed by a variation of 18% in the mean contents of samples collected from different sampling levels, a variation which reaches 41% if the extreme values of all results are taken into account. Regional variations over the Channel as a whole show an asymmetric diminution of the 99Tc content of the seaweed on the two sides of the liquid effluent discharge outlet from the reprocessing plant at La Hague and this confirms a predominant drift of Channel waters towards the North Sea. Variations with time at three stations during 1983 and 1984 have revealed that there is a time-lag between fluctuations observed in the discharges and those in F. serratus. In addition, a periodic component observed at the Roscoff and Wimereux stations, where the 99Tc content of the seaweed varies by a factor of 2–3 between winter and summer periods, could be correlated with seasonal changes both in the metabolic state of F. serratus and in the currents to the south-west of Cap de La Hague. 99Tc, which here has no radiological impact on man, would thus appear to be a radioactive label for sea waters and one which is particularly sensitive to variations in environmental conditions.  相似文献   

18.
Monthly anomalies of stormy wind–wave heights and return periods are evaluated using secular routine observations in the coastal zone of the northern Black Sea. It is shown that wind–wave anomalies in this region are characterized by high-amplitude quasi-periodical variability with typical timescale of about 50 years. This timescale is determined by temporal variability of the coupled ocean–atmosphere system and coincides with periodicity of Atlantic Multidecadal Oscillation. Atmospheric re-analysis data show that cyclonic activity over the Black Sea basin intensifies when North Atlantic is relatively cold and meridional forms of atmospheric circulation are more frequent in the North Atlantic-Eurasian region. This leads to generation of more frequent Black Sea storm events and enhanced recurrence of extreme waves and results in profound (and mostly negative) environmental consequences. When North Atlantic is relatively warm and meridional forms of atmospheric circulation are less frequent in the North Atlantic-Eurasian region, environmental conditions in the Black Sea region are calmer. Thus, statistics of dangerous events can be wrongly estimated even if relatively long-term (~30 years) time series are considered and interdecadal variability of wind–wave anomalies must be taken into account when the risk assessment is accomplished.  相似文献   

19.
An attempt at population analysis of sables in the Ural–Ob region of the species range was made with the use of vast biological material (craniometry, 1909 specimens; ecological structure, 2157 specimens; and coat color, 439169 pelts). Population groups in the region were mainly described on the basis of morphological, geographic, historical, and ecological criteria. Seven spatially separated population groups were found, which were named after the main rivers of their habitats: the Tavda–Konda–Sos'va, Dem'yanka, Salym–Yugan, Agan–Vakh, Kazym–Nazym, Nadym–Kunovat, and Pur–Taz groups. They distinctly differed from one another with respect to cranial measurements, coat color, and some structural demographic parameters. In some cases, morphological differences reached the subspecies level. The data obtained make it possible to revise the pattern of geographic variation within the species range.  相似文献   

20.
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