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1.
Natural resources and raw materials such as metals and minerals are often taken for granted in today’s society. Without them, the offerings of an enormous variety of modern conveniences, including computers and mobile phones, would not be possible. The production of these everyday items depends on a secure, sustainable, and reliable supply of critical raw materials. In addition, product development also requires new hybrid materials when targeting lightweight structures, etc. However, the mandatory recyclability of new products or materials is not obligatory or even prevailing practice in present manufacturing business. Therefore, the main research question in this article is: “how to solve the challenge of recycling in industrial system?” In this article, a comprehensive approach to recycling based on the findings of research projects is presented. Simplified, this involves moving the challenge from the end of the product’s life cycle to the beginning, to the design or even to material development phases. Life cycle and system thinking and material know-how in the design phase are found to be essential elements of a new approach to recycling. This approach stems from the material development and market economy perspectives. Furthermore, the vulnerability of the industrial system to create uncertainty to recycling is also demonstrated.  相似文献   

2.
The overgrowing of meadow-bog communities by shrubs and trees (age 5–40 years, crown closure 0.4–0.9) leads to a decrease in incident illumination. As a consequence, juvenile and generative plants disappear from D. incarnata population loci, their average ecological density decreases, and the loci enter the state of regression. The digging activity of wild boars disrupts phytocenotically closed groups of longirhizomatous herbs, thereby creating favorable conditions for seed reproduction of D. incarnata. The species begins to form population loci with a complete ontogenetic spectrum and high ecological density, eventually restoring the normal (definitive) population structure.  相似文献   

3.
The effect of rise in spring air temperature on the breeding phenology and reproductive success of the Song Thrush in the Voronezh Nature Reserve have been studied over the periods of 1987 to 1990 and 2008 to 2012. The results show that relatively high air temperatures provide for earlier arrival of the birds from wintering grounds, earlier and more synchronous breeding of the majority of nesting pairs, and an increase in clutch size and proportion of pairs producing two broods per season. Predation pressure on bird nests decreases under such conditions, which markedly improves reproductive success. Climate warming is conducive to increasing breeding productivity of the Song Thrush population as a whole.  相似文献   

4.
The significance of colloidal fractions regarding the transport of artificial radionuclides in natural water systems is underlined by using sequential ultrafiltration both in the Rh?ne freshwater and the marine area under and outside the influence of the river outflow. Indeed, the Rhodanian aquatic system represents an interesting test site as various artificial radionuclides are released into the Rh?ne river by several nuclear installations. We focused our study on (137)Cs, (106)Ru, (60)Co, (238)Pu and (239+240)Pu. Our results show that Fe, Al and Organic carbon (OC) are the main components of colloidal matter. Colloids represent about 15% of dissolved (<450 nm) OC and 25% of dissolved Fe and Al exported towards the sea. Within the dissolved (< 450 nm) phase, these colloidal compounds are shown to account for the transport of 40% for both Co and Ru, 60% for (238)Pu and (239+240)Pu and have no significance on (137)Cs flux.  相似文献   

5.
Nowadays, the disparity of the basic pension in local regions of China can be described as follows: the low level of the unification of the basic pension systems, the large disparity of the level of the basic pension, and unfairness of the enterprises’ payment for the basic pension in different local regions in China. These have already brought many negative influences, which have greatly held back the development of the society and national economy. We should build the basic pension system in all local regions of China as a whole, which can cover all people and decrease the disparity in different local regions in China.  相似文献   

6.
With the development of science and technology, the researches and application of water resources including the gas water have been constantly developed. Through an analysis on the flaws of the water right theory, and by executing reconstruction and renewal of the theory and system of water right in modem society, the water right position of the gas water will be established, leading to the maturity of the whole law effectiveness and substantial results of water right.  相似文献   

7.
Quantitative and qualitative characteristics of cones and seeds and the emergence and survival of seedlings in the Siberian spruce (Picea obovata Ledeb.) were studied in different parts of the timberline ecotone on the Iremel’ Massif, the Southern Urals, from 2003 to 2006. In the productive year 2003, a decrease in the number of cones (from 110000 to 3000 per hectare), the yield of seeds (from 13 × 106 to 0.09 × 106 per hectare), and their laboratory germination rate (from 34 to 14%) with an increase in elevation above sea level was recorded. In 2004, significant differences in the number of seedlings per hectare were revealed between the lower, middle, and upper parts of the ecotone (85 200, 19 800, and 0–400 ind., respectively). It has been shown that the greater part of seedlings (76–96%) perish during the first cold period. New generations of spruce trees are formed only after productive years. Seed production and seedling mortality in spruce apparently depend not only on air temperature and soil moistening but also on snow depth and soil temperature, which change more abruptly along the altitudinal gradient.  相似文献   

8.
Environment, Development and Sustainability - Although sustainability assessment is widely discussed at Brazil, in Brazilian Amazon its use is still little applied, considering this territory is...  相似文献   

9.
The carbon emissions in service sectors have attracted increasing attention around the world. However, few studies have examined the driving forces for CO2 emissions from service sectors in developing countries. With the process of accelerating industrialization, China’s service sectors are facing growing pressure to pursue energy savings and emission reductions, especially in several developed regions. In this paper, in order to better understand how CO2 emissions in Beijing’s service sectors have evolved, we utilized a subsystem input–output decomposition analysis to study the pattern and driving factors of consumption-based emissions in Beijing’s service sectors. The results showed that the transportation sector and the Scientific Studies Technical Services sector caused the most CO2 emissions in Beijing’s service sectors. The emission intensity effect potentially reduced CO2 emissions by 10,833 Mt, primarily due to the decreased energy intensity of non-service sectors. Effects of demand and technology were mainly responsible for the increased CO2 emissions in Beijing’s service sectors. Such influence was mainly related to the external component of service sectors, indicating a strong pull effect exerted by service sectors on non-service sectors. Thus, decarbonizing the supply chain of service sectors and improving the energy intensity are necessary to alleviate CO2 emissions in Beijing.  相似文献   

10.
11.
The consideration of a possible enhanced vertical migration of radiocaesium with the application of ammonium-ferric-hexacyano-ferrate (AFCF) as countermeasure, due to the colloidal nature of AFCF, made us set up a series of migration experiments. For the study two soil types were considered, which were either left unplanted or cultivated with ryegrass. Two AFCF concentrations, 1 and 10 g m-2, and an untreated control were applied. A simple diffusion–convection model was fitted to the data.The application of AFCF did not enhance the downward migration of radiocaesium in the profile. Moreover, for an unplanted sandy soil the application of AFCF significantly retarded the migration: 10 g AFCF m-2 decreased the convection term, V, from 0·78 to 0·42 cm a-1 and the diffusion component, D, from 0·21 to 0·09 cm2 a-1. For all other experimental conditions (unplanted loamy soil, ryegrass cultivated sandy and loamy soil), the application of AFCF did not have any effect on radiocaesium migration. Since AFCF does not promote the vertical migration of radiocaesium, enhanced groundwater contamination is improbable.  相似文献   

12.
Data published in the Handbook on the Climate of the Soviet Union have been used as a basis for estimating the temperature of the soil surrounding the nest chamber during the period of bobak marmot hibernation. Interspecific differences in the temperature conditions of hibernation have been revealed. The hypothesis is substantiated that the dates of hibernation onset in marmots depend on air temperature outside the burrow.  相似文献   

13.
With the economic development, China has become the largest CO2 emissions country. China’s power industry CO2 emissions accounted for about 50% of total CO2 emissions. Therefore, exploring major drivers of CO2 emissions is critical to mitigating its CO2 emissions in power industry. Many studies considered the time series model to analyze the national influences factors of CO2 emissions. But this paper focuses on regional differences in CO2 emissions and adopts panel data models to explore the major impact factors of CO2 emissions in the power industry at the regional and provincial perspectives. The results indicate economic growth level plays a dominant role in reducing CO2 emissions. The power-consuming efficiency on the demand side has large potential to mitigate CO2 emissions, but its influences are different in three regions. The impacts of the electric power structure on CO2 emissions decline from the eastern region to the central and western regions. The influence of urbanization and industrialization also has significant regional differences. Therefore, the governments should consider the influencing factors and regional differences and formulate appropriate policies to decrease CO2 emissions in the power industry.  相似文献   

14.
The forest ecosystem of the Orlovskoe Polese National Park has been studied in reference to the reintroduction of a rare species: the European bison (Bison bonasus L.). Preliminary data characterizing the state of forest resources and the populations of ungulates living in the forests, as well as the genetic problems associated with maintaining a viable population of the European bison, are considered.Translated from Ekologiya, No. 2, 2005, pp. 132–137.Original Russian Text Copyright © 2005 by Belousova, Smirnov, Kazmin, Kudrjavtsev.  相似文献   

15.
A hypothesis is considered that the establishment and maintenance of mass exchange processes in the Paramecium bursariasymbiotic complex (infusorian–alga) depends on the presence of the third component—bacteria—whose role is underestimated but essential for completing the exchange cycle. The role of this component in the symbiotic cycle of Paramecium bursariais possible to reveal using special bactericidal preparations specifically inhibiting the bacteria involved in the metabolic cycle but having no effect on the functions of the host cell and the zoochlorella population. Experiments with various preparations of this type were performed, and the response to treatment was estimated from growth rates of the symbiotic complex and its components. This allowed identification of an antibiotic (rifampicin) that had no adverse influence on free-living zoochlorella and chlorella-free paramecia (the basic components of the symbiotic cycle) but drastically inhibited the growth of the P. bursariasymbiotic complex, which could be interpreted as evidence in favor of the hypothesis concerning the existence of the third symbiotic component.  相似文献   

16.
In early 2009, few would have expected that the Intergovernmental Panel on Climate Change (IPCC) would come under such massive attack. The IPCC had enjoyed a pristine reputation and had even advanced to become a role model for biodiversity and food security assessments (Loreau et al. 2006; Watson 2005). However, public trust and, with it, the organization’s credibility eroded dramatically after November 2009 with the events that became known as ‘climategate’. This article seeks to contribute to current debates about how to reform the IPCC. It argues that there are major flaws in the design of the IPCC which are rooted in the linear model of expertise and which are helping to stoke the backlash against the IPCC. The article analyzes the ways in which the IPCC’s activities conform to the linear model of expertise and considers the consequences of this for integrating adaptation into the IPCC assessments. It explains why adaptation played only a marginal role up until the IPCC Third Assessment Report. It then demonstrates why the use of the linear model of expertise constrains the scientific and political debate about adaptation and leads to proxy debates about scientific evidence, which result in depoliticizing the politics of adaptation and politicizing science. Finally, the article calls for the debate to be opened up to accommodate alternatives that are both politically more feasible and at the same time more appropriate to the specific needs of adaptation policies at different levels of decision-making.  相似文献   

17.
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   

18.
How well does the general public understand the concept of urban resilience? We address this question via an online survey of 500+ citizens living in three large Australian cities (Sydney, Melbourne and Perth). The majority of respondents claim not to know what urban resilience means. Of the remaining respondents, understanding ranges from poor to sophisticated. To circumvent this stated lack of understanding, we cast the concept of urban resilience into a more familiar framework consisting of risk and ability to cope with threats. This allows us to assess perceptions about what may challenge the resilience of Australian cities. Two concerns clearly emerge: (1) violence and social unrest and (2) environmental threats. Analysing a number of constructs from the social psychology literature reveals that these two concerns hold different cognitive signatures, whose understanding may facilitate discussion and communication within a public engagement process.  相似文献   

19.
Non-timber forest products (NTFP) represent key sources of cash and subsistence income for millions of rural and indigenous peoples living in tropical developing countries throughout the world. The current study investigates the use and significance of NTFP within a sample of Peninsular Malaysia’s Orang Asli (indigenous people). Data collected via household surveys across three sampling phases reveals that more than 75% of the population is actively engaged in NTFP collection. Household responses indicate diversity in both the types and uses of products collected. NTFP collection participation, frequency of collection, and collection reliance are found to be significantly negatively related to village proximity to the market, as well as to income level relative to the Malaysian poverty line. When collection variables are examined by different product categories, relationships with market access and income group are variable. Implications for different approaches to forest conservation and rural development are discussed.  相似文献   

20.
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