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Gaston Hoffmann Daniel Schingnitz Antje Schnapke Bernd Bilitewski 《Waste management (New York, N.Y.)》2010,30(5):893-901
Climate protection is one of the main aims of environmental policy. One way to advance and push the progress is to reduce the use of fossil fuels for energy production through an increasing production of renewable and CO2-neutral energy for example through application of biomass. This paper sets the focus on biomass streams that can be used both thermal and biological for energy production like grass or energy crops. To calculate the potentials of decrease of CO2-emissions for treatment of biomass in either combustion or digestion plants some scenarios were set up with different assumptions regarding degree of efficiency of treatment plants which depends on size of plants and the treatment process itself. The energetic utilisation of the considered biomass streams is divided in different utilisation scenarios: combined heat and power generation (CHP) and heat generation or power generation only. Additionally four groups of plant sizes referring to electrical power (from 0.1 up to 10.0 MW) were taken into consideration. The calculations of potential savings of CO2-emission in both types of treatment scenarios lead to the result that in comparison to biological technologies thermal processes show a much higher utilisation of the energy content in biomass. 相似文献
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In Germany, plans at the local level to construct wind turbines often find support as well as rejection – often in both cases for ecological reasons. In this paper, we argue that the key to understanding local wind energy debates is to analyse the interrelations between collective identities and concepts of place. Based on the discourse theory of Laclau and Mouffe, we analyse how two completely contradictory place notions have evolved in a local dispute in a small town in Germany, and how existing political identities have been modified, realigned and superseded in the course of the conflict. Furthermore, we show how the involved discourses are characterised by strong continuities with respect to an earlier struggle over an asphalt mixing plant. 相似文献
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ABSTRACTPeri-urban spaces are frontiers of privatisation where inequalities in access to land and water evolve. In this article, we analyse a particular mode of land and water privatisation in peri-urban spaces of the Greater Accra Metropolitan Area (GAMA), Ghana. We illustrate that in the domain of land, traditional authorities tend to act as private owners rather than custodians of customary land, while in the domain of water, multiple private water providers have emerged next to the official water utility. A combined reading and analysis of these processes as forms of de facto privatisation contributes to understanding the similarities in the control over and access to land and water in peri-urban spaces. We show that in the de facto privatised control context of the peri-urban GAMA, access gained to land and water has to be actively maintained. Both gaining and maintaining access exhibit socio-economic inequalities and this is particularly so in the case of maintaining access. The article is a call for a better connection between land and water studies in order to deepen understanding of the processes at play in peri-urban spaces. 相似文献
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Antje Engelhardt Michael Heistermann J. Keith Hodges Peter Nürnberg Carsten Niemitz 《Behavioral ecology and sociobiology》2006,59(6):740-752
One of the basic principles of sexual selection is that male reproductive success should be skewed towards strong males in
species with anisogamous sex. Studies on primate multi-male groups, however, suggest that other factors than male fighting
ability might also affect male reproductive success. The proximate mechanisms leading to paternity in multi-male primate groups
still remain largely unknown since in most primate studies mating rather than reproductive success is measured. Furthermore,
little research focuses on a female’s fertile phase. The aim of this study was to investigate the relative importance of male
monopolisation and female direct mate choice for paternity determination. We also investigated the extent to which paternity
was decided post-copulatory, i.e. within the female reproductive tract. We used a combined approach of behavioural observations
with faecal hormone and genetic analysis for assessment of female cycle stage and paternity, respectively. The study was carried
out on a group of wild long-tailed macaques living around the Ketambe Research Station, Gunung Leuser National Park, Indonesia.
Our results suggest that both male monopolisation and post-copulatory mechanisms are the main determinants of male reproductive
success, whereas female direct mate choice and alternative male reproductive strategies appear to be of little importance
in this respect. Female cooperation may, however, have facilitated male monopolisation. Since paternity was restricted to
alpha and beta males even when females mated with several males during the fertile phase, it seems that not only male monopolisation
but also post-copulatory mechanisms may operate in favour of high-ranking males in long-tailed macaques, thus reinforcing
the reproductive skew in this species. 相似文献
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The information on temperature-mediated changes in biodiversity in local assemblages is scarce and mainly addresses the change in species richness. However, warming may have more consistent effects on species turnover than on the number of species. Moreover, very few studies extended the analysis of changes in biodiversity and species composition to questions of associated ecosystem functions such as primary production. Here, we synthesize 4 case studies employing microalgal microcosms within the Aquashift priority program to ask (1) do warming-related shifts in species richness correspond to changes in the rate of biomass production, (2) do similar relationships prevail for evenness, and (3) do warming-related shifts in species turnover stabilize or destabilize biomass production? Two of the four cases are previously unpublished, and for a third case, the link between diversity and functional consequences of temperature was not analyzed before. We found accelerated loss of species with warming in all cases. Biomass production was lower with lower species richness in most cases but increased with lower evenness. Most importantly, the relation between functional and compositional stability was different between cases: More rapid extinction resulted in more variable biomass in 2 cases conducted with a limited species pool, indicating that compositional destabilization relates to functional variability. By contrast, the only experiment with a large species pool (30 species) allowed previously rare species to become dominant in the community and showed more stable biomass at high turnover, indicating that compensatory dynamics (turnover) can promote functional stability. These 4 independent experiments highlight the need to consider both compositional and functional consequences of altered temperature regimes. 相似文献
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Life cycle assessment-based environmental product declarations (EPDs) require the inclusion of biodiversity impacts across
the entire supply chain. The objective of this study is to test the applicability of a Scandinavian biodiversity assessment
tool, developed specifically for use with EPD applications, in an African desert environment, linking the industry types power
generation and mining. For this purpose, a GIS-based spatial analysis tool—the biotope method—was adapted to a framework approach
which allowed the selection of more suitable, site-specific biodiversity indicators. The biotope method provides a step-by-step
process of defining system boundaries, mapping biotopes, categorizing biotopes based on site-specific indicators, and evaluating
change in biotope status “before” and “after” the impact. The development of site-specific indicators was piloted in this
study and determined by the affected ecosystem and the status of knowledge on biodiversity in this geographic area. Thus plants
were used as indicators for biodiversity, and red-list status and endemism constituted the prime criteria for conservation
value of plants. This in turn represented the key criterion for classifying biotopes. The tested biodiversity assessment tool
has potential for application in different environments and operational settings but leaves room for improvement by including
secondary impacts in the assessment and using a wider range of taxa for indicators of biodiversity. 相似文献
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Dubuc C Muniz L Heistermann M Engelhardt A Widdig A 《Behavioral ecology and sociobiology》2011,65(8):1615-1627
In mammals, when females are clumped in space, male access to receptive females is usually determined by a dominance hierarchy
based on fighting ability. In polygynandrous primates, as opposed to most mammalian species, the strength of the relationship
between male social status and reproductive success varies greatly. It has been proposed that the degree to which paternity
is determined by male rank decreases with increasing female reproductive synchrony. The priority-of-access model (PoA) predicts
male reproductive success based on female synchrony and male dominance rank. To date, most tests of the PoA using paternity
data involved nonseasonally breeding species. Here, we examine whether the PoA explains the relatively low reproductive skew
in relation to dominance rank reported in the rhesus macaque, a strictly seasonal species. We collected behavioral, genetic,
and hormonal data on one group of the free-ranging population on Cayo Santiago (Puerto Rico) for 2 years. The PoA correctly
predicted the steepness of male reproductive skew, but not its relationship to male dominance: the most successful sire, fathering
one third of the infants, was high but not top ranking. In contrast, mating success was not significantly skewed, suggesting
that other mechanisms than social status contributed to male reproductive success. Dominance may be less important for paternity
in rhesus macaques than in other primate species because it is reached through queuing rather than contest, leading to alpha
males not necessarily being the strongest or most attractive male. More work is needed to fully elucidate the mechanisms determining
paternity in rhesus macaques. 相似文献
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Bénédicte Ritt Catherine Pierre Olivier Gauthier Frank Wenzhöfer Antje Boetius Jozée Sarrazin 《Marine Biology》2011,158(6):1187-1210
The Nile Deep-Sea Fan (NDSF) is located on the passive continental margin off Egypt and is characterized by the occurrence
of active fluid seepage such as brine lakes, pockmarks and mud volcanoes. This study characterizes the structure of faunal
assemblages of such active seepage systems of the NDSF. Benthic communities associated with reduced, sulphidic microhabitats
such as sediments and carbonate crusts were sampled by remotely operated vehicles during two cruises in 2006 (BIONIL) and
2007 (MEDECO). Environmental conditions and biological factors including family-level faunal composition, density and diversity
were measured at local and regional scales. Significant differences were detected at different spatial scales: (1) the fauna
of reduced habitats differed substantially in activity, diversity and biomass from the non-seep environment at similar water
depth, (2) cold seep microhabitats showed differences in community structure and composition related to substratum type as
well as to the intensity and location of fluid emissions. 相似文献