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1.
In order to analyze the factors influencing carbon emissions in the region of Beijing–Tianjin–Hebei and to explore the pathways to developing a low-carbon economy, this paper begins with the terminal energy consumption of three industries and residential consumption, and constructs an identical equation which is composed of population size, level of economic development, energy intensity, the proportion of energy consumption, energy structure, and the coefficient of carbon emissions. Based on the data of terminal energy consumption during 2000–2012, various factors are analyzed and their contribution is measured by Logarithmic Mean Divisia Index (LMDI). The results show that the levels of population and economy have a positive driving effect while energy intensity, energy structure, and carbon intensity have a negative driving effect; the proportion of energy consumption had a negative driving effect prior to 2006, then changed to positive. Among suggestions for a low-carbon economy are controlling population size, improving the quality of economic development, supporting research into new energy technology, accelerating regional integration and optimizing industrial structure, and enhancing environmental protection and spreading the concept of a low-carbon economy.  相似文献   

2.
The major problem associated with gravity dam was siltation of reservoir which reduced its effective water storage capacity. In order to maintain effective storage capacity of reservoir, dredging of deposits was required and dredged material was disposed of haphazardly causing damage to the sensitive environment. A better alternative could be the possibility of utilization of dredged deposits in construction works involving large quantities of material. The dredged material consisted of very fine sandy silt possessing poor geotechnical characteristics and was required to be stabilized with suitable additives before use as construction material. This laboratory investigation evaluated geotechnical properties of dredged reservoir material stabilized with cement, fly ash and fiber for its probable use as subbase in lightly trafficked roads. Compaction, unconfined compressive strength and tensile strength tests were performed on appropriate combinations of the constituent materials. The results of study revealed significant improvement in unconfined compressive strength and split tensile strength after stabilization with cement and fly ash. The unconfined compressive strength and split tensile strength of cement–fly ash-stabilized dredged reservoir material improved further upon addition of polypropylene fiber. The composite possessed the potential to be utilized as sustainable material in subbase of roads subject to further validation before application in the field. The dredging of sediments improved effective storage capacity of reservoir and increased its sustainable life period. The utilization of fly ash could diminish the environmental and economic concerns arising out of its haphazard disposal.  相似文献   

3.
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   

4.
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   

5.
Drought in the northern part of Cyprus has become a recurrent phenomenon. In the last few decades, Cyprus has experienced significantly severe drought events occurring periodically, and this trend is now continuing. With rainfall distribution varying considerably across the region and frequent drought conditions, the water resources, agriculture, economy and the environment have been adversely affected. This study aims to investigate spatial–temporal characteristic of drought using Standardized Precipitation Index (SPI) at multiple timescales (3, 6 and 12 months). Monthly time series of 36 years (1977–2013) rainfall data from nine weather stations are used to derive SPI values. Based on different drought categories, this study focuses on propagation of drought from one timescale to another and estimating critical rainfall values during moderate, severe and extreme drought conditions. The analysis revealed that there is a strong correlation among different timescales in detecting drought events. On average, 79 and 78% of 3-month timescale drought propagated into 6- and 12-month drought events, respectively, while 90% of 6-month timescale drought events propagated into 12-month drought events. The derived critical rainfall value for extreme droughts over a 12-month timescale was less than 255 mm/year in the town of Alsancak, while for Guzelyurt, a major citrus growing city, this figure was less than 135 mm/year. The results are validated through drought events detected at various regions of the Mediterranean basin and local flood occurrences during the wet periods and decline in water tables at drought seasons.  相似文献   

6.
Nowadays, many countries are looking towards sustainability as a goal because our world has limited resources and serious environmental impacts. In the construction industry, the process of sustainable selection of structural material is considered one of the keys to achieve more sustainable construction. In this paper, the theories of decision making are utilised to develop an approach for evaluation and ranking the structural materials over their total life based on sustainability criteria using multi-attribute decision-making methods. One of them is Analytical Hierarchy Process which is utilised to build the problem hierarchical structure and assign weights of the predetermined sustainable factors. The other is Technique for Order Preference by Similarity to the Ideal Solution which is utilised to rank the structural materials within both each material life cycle phase and the complete material life cycle phases. The third is the concept of entropy by Shannon to evaluate the weight factor for each phase of material life cycle. The proposed approach presents an objective, systematic and comprehensive method for the sustainable ranking of materials that links between the structural element design and the sustainable selection of materials.  相似文献   

7.
Snow cover in Spanish mountains is crucial for ensuring water availability in spring and summer months, for the success of winter tourism or for the maintenance of biodiversity in mountain ecosystems. A changing climate may affect the volume of snow cover even in high mountains, where weather conditions are usually favorable for snow accumulation. In this paper, we aim to investigate the evolution (1970–2007) of combined precipitation–temperature modes in the Spanish mountains, and the sensitivity of the snowpack to their occurrence. The climatic database “Spain02” and snow thickness data for Spanish mountains were used for this purpose. Results showed that the frequency of dry-warm and wet-warm days has increased over time in all mountain ranges, while the frequency of the “cold” modes has decreased. The thickness of the snowpack in the Pyrenees has also decreased and its evolution is negatively correlated with the frequency of dry-warm days, and positively correlated with the frequency of dry-cold and wet-cold days. This work constitutes the first approach that relates the evolution of climatic conditions favorable or unfavorable for snow accumulation and the evolution of the snowpack in Spanish mountains.  相似文献   

8.
The relationship between Scots pine (Pinus sylvestris L.) tree-ring width and temperature and precipitation was analyzed in pine forests on the Bugulma–Belebey Upland, Bashkiria. A close correlation between tree-ring width and the current spring–summer precipitation was revealed. On this basis, a reconstruction of May–June precipitation in the period from 1860 to 1994 was made.  相似文献   

9.
The horizontal distribution and quantitative characteristics of macrozoobenthos were studied in small lakes of the Darwin Nature Reserve (southern Vologda oblast). The aggregation index varied in the open areas of acid lakes, which indicated that communities of small acid water bodies were unstable. The aggregation was the lowest in the open area of a neutral lake. In acid lakes, the number and biomass of macroinvertebrates were the highest near the coasts. In the neutral lake, conversely, these values were maximum in open areas and low near the coast due to a strong pressure of predatory invertebrates and fish. An aggregating effect of invertebrate predators was observed near the coasts of lakes of different types.  相似文献   

10.
Trends in the altitudinal and sectoral structural variation of ecosystems in mountain areas are considered using an example of mammals as an important component of ecosystems. With consideration of the environment-forming ecogeographic factors, a hierarchical system of taxa reflecting the altitudinal zonal structure of ecosystems of mountain landscapes is proposed. The system includes six categories: (1) mountain ecosystem kingdom; (2) mountain land; (3) cohort of zonality types; (4) zonality type; (5) zonality subtype; and (6) variant of zonality. As a model of the mountain land taxon as a subunit of the mountain ecosystem kingdom, the theriofauna of the Caucasus is considered. The Caucasus is a unique mountain land where two cohorts of zonality types, five zonality types, two zonality subtypes, and 14 zonality variants are well defined. It is shown that the contribution of landscape sectoral heterogeneity to the formation of biological diversity in mountain territories is more substantial than that of altitudinal heterogeneity. The altitudinal zonality of mountain landscapes plays the role of a matrix of the variation of biological systems at all levels of living matter organization.  相似文献   

11.
Fars has a special place in Iran in terms of natural resources and diverse climate aiming this province to increase production of major crops such as corns. In light of increasing domestic production and preventing yield loss of maize, many farmers utilize high quantities of pesticides, chemical fertilizers and over-extract groundwater without considering immediate and long-term consequences of such operations on environment. The main purpose of this study is to investigate technical efficiency and sustainability–technology gap ratio (STGR) of maize producers by agricultural sustainability in Fars province in Iran. Technical efficiency is considered as a key element among the triple elements of sustainable development (economic, social and ecological). Applying model of agricultural sustainability and compromise programming method, regions were classified into three groups (sustainable, relatively sustainable and unsustainable), and data were collected interviewing a total of 300 farmers in 2008–2009 from Kazerun, Firouzabad and Marvdasht chosen randomly and systematically as representatives of these three groups. Technical efficiencies and STGRs were calculated for the regions applying stochastic production frontier, regional stochastic frontier functions and the metafrontier. The results indicate that assuming the same technology between the fields (traditional methods) leads to overestimation of technical efficiency. Mean STGRs in Marvdasht, Firouzabad and Kazerun were found to be 59.3, 71.1 and 68.9, respectively. This suggests that technical efficiency and STGR of relatively sustainable regions are higher than those of the unsustainable regions. Thus, farmers in these areas can reduce gap between technology and agricultural sustainability levels via achieving metatechnology that is compatible with sustainable agriculture.  相似文献   

12.
13.
Mullite-based glass-ceramics were produced from aluminium hydroxide sludge resulting from the anodisation process and waste glasses. Phase development for crystallisation of amorphous mullite was investigated between 900°C and 1200°C. The kinetic parameters such as activation energy of crystallisation and Avrami exponent for the samples were evaluated from differential thermal analysis curves using various heating rates (5–30°C) and particle size ranges ( < 45, 80–125 and 355–400 μm). The growth morphology parameters ‘n’ and ‘m’ are in the range of 2.5–5.4 and 1.5–4.4, respectively, indicating that bulk nucleation is dominant in mullite crystallisation followed by two- to three-dimensional growth of mullite crystals controlled by diffusion from a varying number of nuclei.  相似文献   

14.
The sustainability of deltas worldwide is under threat due to the consequences of global environmental change (including climate change) and human interventions in deltaic landscapes. Understanding these systems is becoming increasingly important to assess threats to and opportunities for long-term sustainable development. Here, we propose a simplified, yet inclusive social–ecological system (SES)-centered risk and vulnerability framework and a list of indicators proven to be useful in past delta assessments. In total, 236 indicators were identified through a structured review of peer-reviewed literature performed for three globally relevant deltas—the Mekong, the Ganges–Brahmaputra–Meghna and the Amazon. These are meant to serve as a preliminary “library” of potential indicators to be used for future vulnerability assessments. Based on the reviewed studies, we identified disparities in the availability of indicators to populate some of the vulnerability domains of the proposed framework, as comprehensive social–ecological assessments were seldom implemented in the past. Even in assessments explicitly aiming to capture both the social and the ecological system, there were many more indicators for social susceptibility and coping/adaptive capacities as compared to those relevant for characterizing ecosystem susceptibility or robustness. Moreover, there is a lack of multi-hazard approaches accounting for the specific vulnerability profile of sub-delta areas. We advocate for more comprehensive, truly social–ecological assessments which respond to multi-hazard settings and recognize within-delta differences in vulnerability and risk. Such assessments could make use of the proposed framework and list of indicators as a starting point and amend it with new indicators that would allow capturing the complexity as well as the multi-hazard exposure in a typical delta SES.  相似文献   

15.
Singular Spectrum Analysis (SSA) has been used to decompose continuous series of data on certain characteristics of Lake Naroch’ ecosystem during the vegetative seasons of years 1978–2015 into a long-time trend, a periodic component, and a residue not amenable to decomposition. The contribution of each component to changes in this variable has been assessed. The trends accounted for 78–97% of parameter variability, and the periodic components accounted for 2.5–15%. The fluctuations of phytoplankton and zooplankton biomass dynamics were the most diverse, and the contribution of these components was the greatest (15 and 8%, respectively). The periodic components in the changes of all parameters could be divided into four groups according to period duration (17–22, 7–15, 4–7, and less than 4 years). Multidimensional factor analysis of seven biotic parameters was performed in order to identify fluctuations in the ecosystem. Five major factors accounting for 93.6% of ecosystem changes together were identified, and each factor variable was subjected to SSA analysis. The period durations were similar for the oscillatory components identified. The first factor was interpreted as a trophic status of the water body, the second was taken to be the geographical location that defines the amount of solar radiation energy available, the third was taken to be the availability of biogenic elements (phosphorus in particular), and the fourth was interpreted as specific developmental cycles of live components of the ecosystem.  相似文献   

16.
The Jordan River is among the world’s most famous and culturally and historically significant waterways. The lower stretch of the river, however, has been a victim of development in a water scarce region, with current flows less than 5 % of historical levels. Furthermore, as it functions as an international border in a region of conflict, access to the river and its potential as a tourist attraction has been limited. Recently, there have been numerous calls for rehabilitation of the river. This study presents a first estimate of the economic benefits of such rehabilitation and compares them to the estimated costs. Identical contingent valuation method surveys were administered in Israel, Jordan, and the Palestinian Authority. Evidence from this study shows that, despite the large opportunity costs of increasing environmental flows, rehabilitation of the lower Jordan would produce positive net economic benefits. This is true even though the study estimated only the benefits to local populations, and not to international tourists or those outside the region. Net benefits are maximized when taking a regional, as opposed to strictly national, approach.  相似文献   

17.
Fertilization with 2.5 t/ha limestone: (83% CaCO3, 8% MgO, 6% K2O, 3% P2O5) reduces the 137Cs transfer from spruce forest soil into plants like fern (Dryopteris carthusiana) and blackberry (Rubus fruticosus) by a factor of 2–5 during at least 11 years as measured by the aggregated transfer factor Tag. In 1997 and 2006 these results were confirmed by additional measurements of the 137Cs transfer factor TF, related to the root zone (Oh horizon), which were explained by the selective sorption of 137Cs in the root zone by measurements of the Radiocaesium Interception Potential (RIP) in fertilized (RIP > 179 meq/kg) and non-fertilized soils (RIP < 74 meq/kg).  相似文献   

18.
19.
Successful conservation efforts require understanding predictors of private-land stewardship (PLS), its definitions, and what people feel they owe stewardship responsibility to. Various strands of research have touched on the concept, but there is little research focusing on how it is communicated and enacted among the lay public, especially among Latinos. We used a case study in the Lower Rio Grande Valley of Texas to address this gap by identifying and assessing Latino views of PLS. Our results indicate positive relationships between self-identification as a land steward, male gender, and agricultural-land ownership. Respondents associated PLS with property maintenance (60%), natural-resource conservation (14%), and addressing pollution problems (21%). They viewed PLS as a responsibility owed to family rather than to a larger community.  相似文献   

20.
Biomass fuels have attracted an increase in interest due to the alarming rise in global greenhouse gases and the rapid rise of petroleum prices. Energy security on a sustainable basis can come only with the responsible use of home-sourced resources and not from imported fossil fuels such as coal or crude petroleum products. Partial combustion of biomass in the downdraft gasifier generates producer gas that can be used as the sole fuel or as a supplementary fuel for internal combustion engines. A dual fuel mode of operation, in which producer gas is used as a supplementary inducted fuel along with injected pilot fuels of Honge or Jatropha biodiesels, can be a promising alternative to diesel only usage. Two different carburettors were designed and fabricated to facilitate gas entry at 45° and 90° to the engine cylinder. The engine was experimentally optimised using Honge or Jatropha biodiesels–producer gas combinations with respect to maximum pilot fuel savings in the dual fuel mode operation, optimum air and gas mixing with different tested carburettors. The performance, combustion and emission characteristics of these dual fuel combinations were compared at different load conditions. The results showed that biodiesels of Honge or Jatropha oils–Producer gas combinations with carburettor of 90° gas entry resulted in better performance.  相似文献   

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