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1.
Rust belt cities of the northeastern United States are plagued by flat or declining economies and the accompanying social fallout from lack of employment. Advocates of green fuels, green infrastructure and green jobs have proposed these nature-based technologies as means to revitalize the economies of cities. Before making public and private investment a baseline analysis of the relative magnitude of existing energy production and energy respiration at the neighborhood scale is useful in order to understand what the potential for green infrastructure might be. Because the urban canopy and other green infrastructure can enhance urban socio-ecological metabolism, we measured the flows of natural energy produced (P) by the urban forest versus the industrial or fossil energy currently consumed or respired (R) in three economically and demographically distinct neighborhoods of a typical rust-belt city, Syracuse, NY. Our objectives were to (1) understand the potential for green energy to replace fossil fuels in general, (2) assess the degree to which different socio-demographic communities are receiving the ecosystem benefits of existing urban “green” infrastructure (i.e. forest primary production), and (3) identify where local (in-city) biotic energy resources could be enhanced or fossil fuel consumption altered to improve overall urban socio-ecological metabolism. We found that (1) the fossil energy consumed in all three neighborhoods was 200-700 times higher than the biotic “green” energy produced; (2) that to produce this much energy from willow biomass grown in the region would require at least between 0.3 and 0.7 ha of bio-energy production per person depending on affluence, density of living, transportation mix and home fuel mix; (3) that although the more affluent neighborhood used, per residence and per person, almost twice as much energy as that of the downtown more densely settled and poorer neighborhood, its R:P ratio was still the lowest due to the high primary productivity of its neighborhood tree canopy. As a first assessment our findings identify several opportunities for enhancement of the socio-ecological metabolism of these neighborhoods, and the city at large, through conversion of heating units in poorer neighborhoods away from expensive electricity, and toward tree planting, solar installations, and per capita energy use reductions.  相似文献   

2.
Measuring the amount of fossil fuel carbon stored in the vegetation is now crucial to understand the mechanisms ruling climate changes. In this respect, highly polluted areas such as major towns represent “natural” laboratories because fossil fuel CO2 (14C-free) is isotopically distinct from mean atmospheric CO2 (14C-labeled). Here, a14C study of urban grasses near a major highway in Paris, France, shows that plants store up to 13% of fossil fuel carbon. The 14C composition of urban grasses is thus a novel parameter to assess the fossil fuel CO2 pollution.  相似文献   

3.
An assessment of air quality of Belgrade, Serbia, was performed by determining the trace element content in airborne daily PM10 and PM2.5 samples collected from a central urban area. The ambient concentrations of Zn were the highest in PM2.5 (1,998.0 ng m−3). Multivariate receptor modelling (principal component analysis and cluster analysis) has been applied to determine the contribution of different sources of specific metallic components in airborne particles. The obtained results showed that vehicle traffic and fossil fuel combustion in stationary objects were the main sources of trace metals in Belgrade urban aerosols.  相似文献   

4.

The global shift from a fossil fuel-based to an electrical-based society is commonly viewed as an ecological improvement. However, the electrical power industry is a major source of carbon dioxide emissions, and incorporating renewable energy can still negatively impact the environment. Despite rising research in renewable energy, the impact of renewable energy consumption on the environment is poorly known. Here, we review the integration of renewable energies into the electricity sector from social, environmental, and economic perspectives. We found that implementing solar photovoltaic, battery storage, wind, hydropower, and bioenergy can provide 504,000 jobs in 2030 and 4.18 million jobs in 2050. For desalinization, photovoltaic/wind/battery storage systems supported by a diesel generator can reduce the cost of water production by 69% and adverse environmental effects by 90%, compared to full fossil fuel systems. The potential of carbon emission reduction increases with the percentage of renewable energy sources utilized. The photovoltaic/wind/hydroelectric system is the most effective in addressing climate change, producing a 2.11–5.46% increase in power generation and a 3.74–71.61% guarantee in share ratios. Compared to single energy systems, hybrid energy systems are more reliable and better equipped to withstand the impacts of climate change on the power supply.

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5.
The snow leopard (Panthera uncia) inhabits the rugged mountains in 12 countries of Central Asia, including the Tibetan Plateau. Due to poaching, decreased abundance of prey, and habitat degradation, it was listed as endangered by the International Union for Conservation of Nature in 1972. Current conservation strategies, including nature reserves and incentive programs, have limited capacities to protect snow leopards. We investigated the role of Tibetan Buddhist monasteries in snow leopard conservation in the Sanjiangyuan region in China's Qinghai Province on the Tibetan Plateau. From 2009 to 2011, we systematically surveyed snow leopards in the Sanjiangyuan region. We used the MaxEnt model to determine the relation of their presence to environmental variables (e.g., elevation, ruggedness) and to predict snow leopard distribution. Model results showed 89,602 km2 of snow leopard habitat in the Sanjiangyuan region, of which 7674 km2 lay within Sanjiangyuan Nature Reserve's core zones. We analyzed the spatial relation between snow leopard habitat and Buddhist monasteries and found that 46% of monasteries were located in snow leopard habitat and 90% were within 5 km of snow leopard habitat. The 336 monasteries in the Sanjiangyuan region could protect more snow leopard habitat (8342 km2) through social norms and active patrols than the nature reserve's core zones. We conducted 144 household interviews to identify local herders’ attitudes and behavior toward snow leopards and other wildlife. Most local herders claimed that they did not kill wildlife, and 42% said they did not kill wildlife because it was a sin in Buddhism. Our results indicate monasteries play an important role in snow leopard conservation. Monastery‐based snow leopard conservation could be extended to other Tibetan Buddhist regions that in total would encompass about 80% of the global range of snow leopards. Papel de los Monasterios Budistas Tibetanos en la Conservación del Leopardo de las Nieves  相似文献   

6.
With growing levels of human-activity and frequent natural disturbances throughout the world, it is increasingly important that both research and management efforts take into account the widespread landscape fragmentation and its consequences for biodiversity conservation. The magnitude 5.12 Wenchuan earthquake in China caused dramatic impacts on giant panda (Ailuropoda melanoleuca) habitat in the nature reserves within Minshan and Qionglai mountains. With the combined stresses of the natural disaster and the extensive human activities during postquake reconstruction, giant panda habitat in this region may become more fragmented in the future. In order to preserve the giant panda population after the earthquake and protect the species against habitat fragmentation, this article explores a method of identifying giant panda migration corridors involving habitat suitability assessments and a least-cost path model. Focusing on postquake Wolong Nature Reserve, our results demonstrate that it contains 430.3 km2 of suitable habitat (21.1% of total area), 463.8 km2 of marginally suitable habitat (22.8%) and 1141.9 km2 of unsuitable habitat (50.1%). We further show that several giant panda dispersal corridors exist in the reserve, including four corridor groups that cross the provincial highway and five corridors that do not intersect areas of human activity. This study will contribute to management and conservation efforts in Wolong Nature Reserve and beyond after the Wenchuan earthquake.  相似文献   

7.
Sea water and fish tissue samples were collected from nine sampling stations from the Great Bitter and El Temsah lakes in the Suez Canal and analysed for polycyclic aromatic hydrocarbon (PAH). The compositions of PAH determined in the dissolved fraction of sea water were measured in order to use them as chemical markers for identifying different sources of PAH pollution in this region. PAHs determined in fish tissues were measured for comparison with human health standards as consumption. The total mean PAHs concentrations in the sea water samples ranged from 0.28 to 39.57 μg l?1 with an overall mean of 10.78 and 12.38 μg l?1 for El Temsah and Bitter Lakes water, respectively. Total PAHs fractions recorded in muscle tissues of all different Osteicthyes fishes collected from Great Bitter lakes ranged from 5.8 to 218.5 μg g?1 with an overall mean of 57.98 μg g?1 during all seasons. However, they ranged from 68 to 623 μg g?1 with an overall mean of 87.69 μg g?1 recorded in El Temsah lake during four seasons (2003–2004). Benzo(a)pyrene was the most dominant PAHs found in the sea water samples from both lakes with an average concentration of 3.8 μ g l?1. Dibenzo(a,h)anthracene (DBA) was the most dominant PAHs recorded in fish samples. A maximum of 533 μg g?1 of DBA was recorded in Dahbana sp. collected from Bitter lakes during January 2004. However, a maximum of 68.7 μ g g?1 was recorded in Liza carinata species collected from El Temsah lake during July, 2004. The simultaneous occurrence of isomer ratios PHE/ANT<10 for all stations indicated that the major PAH input to water was from combustion of fossil fuel (pyrolytic source). The average ratios were 1.21 and 12.9 during winter (January 2004) and 4.3 and 8.63 during spring (April 2004) for all water samples of Great Bitter lakes and El Temsah lake, respectively. In addition, the present data demonstrate that PAHs from fossil fuel sources (MW<178) were the least significant source of PAHs in this region.  相似文献   

8.
Radiocarbon from nuclear fallout is a known health risk. However, corresponding risks from natural background radiocarbon incorporated directly into human genetic material have not been fully appreciated. Here we show that the average person will experience between 3.4 × 1010 and 3.4 × 1011 lifetime chromosomal damage events from natural background radiocarbon incorporated into DNA and histones, potentially leading to cancer, birth defects, or accelerated aging. This human genetic damage can be significantly reduced using low radiocarbon foods produced by growing plants in CO2 recycled from ordinary industrial greenhouse gas fossil fuel emissions, providing additional incentive for the carbon sequestration.  相似文献   

9.
This work analyses effects of recent variations in the tidal inundation frequency in a mangrove ecosystem in the Bragança peninsula, North Brazil, and its implications for land occupation and use. Field data, time series of remote sensing images and local legislation were analysed focusing on the potential socio-economic impact of a changing environmental setting due to a rise in relative sea level. In the investigated period (1972–1997), vegetation changes along the coastline indicate net losses of mangrove coverage. In the central part of the peninsula, a topographically higher herbaceous plain constituting part of a farm presents an active progression of mangrove forest into an area previously dominated by grasses and herbs. This area measured 8.8 km2 in 1972 but was gradually reduced to 5.6 km2 in 1997, while progressively replaced by a monospecific stand of the black mangrove,Avicennia germinans. A linear extrapolation indicates that the elevated plain may be completely covered by mangrove by 2035. Current Brazilian legislation prohibits the extraction of mangrove trees without an officially approved management plan. Thus, the usable area of the farm has suffered a reduction by ca. 36% over 25 yr and we predict that is could be entirely replaced by mangroves in the next 35 yr. In this case study, legislation and ecosystem characteristics are analysed and a management plan discussed which could represent income alternatives for affected resource users at the local and regional level.  相似文献   

10.

The spatial and temporal distribution pattern is an outstanding feature of the relationship among ecosystem services (ESs) that explains links between human activities and disturbed chemical composition of ecosystems. This study investigated the spatiotemporal variation of land use/cover changes (LUCC) and quantifies the change in four essential ecosystem services with an emphasis on soil (nutrient delivery ratio, carbon storage, crop production, and water yield) and their relationships in the Jiroft plain, Iran, during 1996–2016 through analytical tools including Land Change Modeler, and the Integrated Valuation of Ecosystem Services and Tradeoff. During the 20-year concentrate period, there was a considerable overall gain in cropland (5396 km2) and urban (1787 km2), loss of unused land (5692 km2), water (2088 km2), and forest (1083 km2). As a result of LUCC, while crop production and nutrient delivery ratio showed a rising trend, overall carbon storage and water yield decreased. The spatiotemporal trade-off between carbon storage and crop production, the temporal trade-off between crop production and water yield, and synergy between water yield and crop production were widespread in Jiroft plain. These results showed that the interaction among ESs mutates over time and can be changed under planning and policies. This study will enrich the research of the geographical distribution of ESs interaction in dryland ecosystems to provide practical ecosystem management under local conditions.

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11.
Increasing growth in the aquaculture industry demands ecosystem-based techniques for management if that growth is to be ecologically sustainable and promote equity among users of the ecosystems in which it occurs. Models of carrying capacity can be used to responsibly limit the growth of aquaculture in increasingly crowded coastal areas. Narragansett Bay, Rhode Island, USA is one such crowded coastal region experiencing a rapid increase in bivalve aquaculture. An ecosystem mass-balance model was used to calculate the ecological carrying capacity of bivalve aquaculture. Cultured oyster biomass is currently at 0.47 t km−2 and could be increased 625 times without exceeding the ecological carrying capacity of 297 t km−2. This translates to approximately 38,950 t of harvested cultured oysters annually which is 4 times the total estimated annual harvest of finfish. This potential for growth is due to the high primary productivity and large energy throughput to detritus of this ecosystem. Shellfish aquaculture has potential for continued growth and is unlikely to become food limited due, in part, to the large detritus pool.  相似文献   

12.
Studies about wetlands have been identified as a key component of environmental change. The present study assesses the spatio-temporal changes in the wetlands of the Great Rann of Kachchh, in the Kachchh Biosphere Reserve, India, using remote sensing and GIS techniques. Satellite time-series data from Landsat (1977, 1990 and 1999) and IRS P6 (2006, 2008–2012) were used. The Normalised Difference Water Index (NDWI) was derived for each year and the layers were manually edited to obtain a high classification accuracy. The analysis found that the area has undergone considerable change from 1977 to 2011. The natural wetland area of 30.6 km2 was converted to salt pans. An area of about 255 km2 (41.6 %) of natural grassland was invaded by Prosopis juliflora, which raises further conservation concerns and emphasises the importance of having intervention plans to manage this ecosystem. The highest water spread of 1171 km2 was observed in September 2011, followed by 2010, 2009 and 2008 in the same month. The present study is useful in planning the long-term management and conservation of the Great Rann of Kachchh wetland.  相似文献   

13.
Environmental Chemistry Letters - Climate change and the unsustainability of fossil fuels are calling for cleaner energies such as methanol as a fuel. Methanol is one of the simplest molecules for...  相似文献   

14.
Urbanization has created a significant gap between the Three Northeast Provinces (TNP) and the Yangtze River Delta (YRD) since China’s reform and opening-up. In this study, we explain this problem by employing an urban expansion index, spatial hierarchical clustering, the Zipf-PLE model, fractal theory, and time-series analysis. Statistical data on the built-up area, population, and gross domestic product were downloaded from the National Bureau of Statistics of China. The results revealed the following. (1) During the stage of the planned economy, as a result of the significant government investment in development, the urban built-up areas in the TNP and the YRD reached 1867 and 757 km2, respectively, in 1984. (2) During the stage of the socialist market economy, the urban built-up area of the YRD experienced rapid growth over the 30 years from 1984 to 2014 with a rate of increase of 668.8%, which was higher than that of the TNP (139.9%). In 2014, the urban built-up areas of the TNP and the YRD were 4479 and 5820 km2, respectively. (3) Locational advantages had significant effects on urban development after China’s economic reform. The coastal cities of the YRD had higher rates of increase of the built-up areas. By contrast, the border cities of the TNP had lower rates of increase. Finally, this paper finds that the socialist market economy exhibited more efficiency in promoting urban expansion and economic development. The results are significant for generating balanced and sustainable regional development strategies in the future.  相似文献   

15.
A model for the accumulation of CO2 in the atmosphere has been set up, taking into consideration: (1) the global cycle of nitrogen and phosphorus: (2) the CO2-diffusion in the oceans with means of a multilayer ?ea model; (3) the ability of the oceans to take up CO2; (4) the influence of the CO2-concentrations and of the temperature on this ability; (5) different growth rates for the consumption of fossil fuel including logistic growth; (6) the natural climatic variation.It is shown to be essential to include all these factors. The inclusion of factors (4) and (6), which have been omitted in many previous publications, is very essential to the model.  相似文献   

16.

Energy derived from fossil fuels contributes significantly to global climate change, accounting for more than 75% of global greenhouse gas emissions and approximately 90% of all carbon dioxide emissions. Alternative energy from renewable sources must be utilized to decarbonize the energy sector. However, the adverse effects of climate change, such as increasing temperatures, extreme winds, rising sea levels, and decreased precipitation, may impact renewable energies. Here we review renewable energies with a focus on costs, the impact of climate on renewable energies, the impact of renewable energies on the environment, economy, and on decarbonization in different countries. We focus on solar, wind, biomass, hydropower, and geothermal energy. We observe that the price of solar photovoltaic energy has declined from $0.417 in 2010 to $0.048/kilowatt-hour in 2021. Similarly, prices have declined by 68% for onshore wind, 60% for offshore wind, 68% for concentrated solar power, and 14% for biomass energy. Wind energy and hydropower production could decrease by as much as 40% in some regions due to climate change, whereas solar energy appears the least impacted energy source. Climate change can also modify biomass productivity, growth, chemical composition, and soil microbial communities. Hydroelectric power plants are the most damaging to the environment; and solar photovoltaics must be carefully installed to reduce their impact. Wind turbines and biomass power plants have a minimal environmental impact; therefore, they should be implemented extensively. Renewable energy sources could decarbonize 90% of the electricity industry by 2050, drastically reducing carbon emissions, and contributing to climate change mitigation. By establishing the zero carbon emission decarbonization concept, the future of renewable energy is promising, with the potential to replace fossil fuel-derived energy and limit global temperature rise to 1.5 °C by 2050.

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17.
The ecological footprint (EF) is a method for measuring sustainable development through ecological impact. A methodology is presented for predicting urban ecological footprints. Urban energy use and natural resource consumption were analyzed to calculate an EF based on land type (arable, pasture, forest, fossil energy land, built-up area and water area) and consumption (food, housing, transportation, goods, services and waste). The result was then compared with the local ecological carrying capacity to develop criteria for sustainable ecological footprints. Case studies of four cities in China (Guangzhou, Ningbo, Suzhou and Yangzhou) illustrate the urban EF approach. The time series of EF in a case study of Guangzhou for 1991–2001 was analyzed and the consumption–land-use matrix of urban EF was established. The results show that the cities are ecologically unsustainable, with average ecological conflicts per capita of more than 2 ha. The urban EF method is useful to measure urban sustainable development and provides policy proposals for decision-making. However, the EF method still has limitations and weaknesses.  相似文献   

18.
The nitrogen emission from household food consumption (NEHFC) has played a vital role in sustainability development. Recent changes in household dietary have significantly accelerated reactive nitrogen emissions in China. However, the spatial patterns and dynamics of these flows between urban and rural areas remain unclear. Based on material flow and spatial-temporal analysis, our study investigated the patterns of Chinese urban-rural NEHFC during 1993–2015. Increasingly apparent regional disparities were found in both the spatial patterns of urban-rural NEHFC during the study period. Notably, the spatial autocorrelation of urban NEHFC demonstrated a ‘U’ type, compared with a recent decreasing Moran’s I index of rural NEHFC. Moreover, the regional spatial-temporal variation of per capita urban NEHFC exhibited ‘South (High)-North (Low)-Middle (Fast)’ trend. By contrast, the hotspot of per capita rural NEHFC mainly concentrated in South-eastern China with a distinct regional changing of ‘Middle-east (Fast) & west (Slow).’ The Social-Economic and Regional-Development Index were far more critical than the Natural-Geographic Index to the spatial-temporal variation of per capita urban NEHFC, whereas the rural NEHFC was driven by the combined actions of all the three indexes. Our study highlighted the necessity of ‘Location-Suitable’ and ‘Urban-rural recycling’ nitrogen management strategies for reducing the risk of NEHFC in China.  相似文献   

19.
Ecosystems are balanced by nature and each component in the system has a role in the sustenance of other components. A change in one component would invariably have an effect on others. Stomatopods (mantis shrimps) are common and ecologically important predatory crustaceans in tropical marine waters. The ecological role of mantis shrimps and potential impacts of trawling in a marine ecosystem were estimated using Ecopath with Ecosim (EwE) Version 5.0 software, by constructing a mass balanced Ecopath model of Parangipettai (Porto Novo) ecosystem. Based on fisheries information from the region, 17 ecological groups were defined including stomatopods. Both primary and secondary data on biomass, P/B, Q/B and diet composition were used as basic inputs. The mass balanced model gave a total system throughput of 14,756 t km−2 year−1. The gross efficiency of 0.000942 indicated higher contribution of lower food chain groups in the fishery though the mean trophic level was 3.08. The immature and developing stage of the ecosystem was indicated by the ratio of total primary production and total respiration (1.832) and the net system production (2643.30 t km−2 year−1). Key indices (flow to detritus, net efficiency and omnivory index), split mortality rates and mixed trophic impact of different ecological groups were obtained from the model. A flow diagram was constructed to illustrate the trophic interactions, which explained the biomass flows in the ecosystem with reference to stomatopods. Two temporal simulations were made, with 10 year durations in the mass balanced Ecopath model by using ecosim routine incorporated in EwE software. The effect of decrease in biomass of stomatopods in the ecosystem was well defined, in the first run with increase in stomatopod fishing mortality, and the group showed a high positive impact on benthopelagic fish biomass increase (129%). The simulation with increase in trawling efforts resulted in the biomass decline of different ecological groups as elasmobranchs to 1%, stomatopods to 2%, crabs and lobsters to 36%, cephalopods to 63%, mackerel to 78%, and shrimps to 89%. Present study warns stomatopod discards and further increase in trawling efforts in the region and it explained the need for ecosystem based fisheries management practices for the sustainability of marine fisheries.  相似文献   

20.
Assuming that the landscape physiographic characteristics strongly determine the occurrence of land use and land cover types, this study assessed the distribution patterns of natural and converted classes in relation to the major geomorphological units and slope ranges in the central area of continuous savanna formations in Brazil (Cerrado biome), the country’s most important region for cattle ranching and intensive commodity crops. Our results showed that 93% of the agriculture activities are concentrated at slopes of less than 5°, mostly associated to old regional planation surfaces (RPSs). Considering the amount of remnant vegetation and the occupation and land use deterministic trends, we estimated that between 58,041 km2 and 79,677 km2 of conversions may occur in the near future. If the priority areas for biodiversity conservation are properly enforced and effectively incorporated into the system of fully protected areas and areas of sustainable use, a decrease of approximately 24% in the expected potential deforestation could be achieved.  相似文献   

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