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71.
Angelstam P Mikusiński G Rönnbäck BI Ostman A Lazdinis M Roberge JM Arnberg W Olsson J 《Ambio》2003,32(8):527-534
The maintenance of biodiversity by securing representative and well-connected habitat networks in managed landscapes requires a wise combination of protection, management, and restoration of habitats at several scales. We suggest that the integration of natural and social sciences in the form of "Two-dimensional gap analysis" is an efficient tool for the implementation of biodiversity policies. The tool links biologically relevant "horizontal" ecological issues with "vertical" issues related to institutions and other societal issues. Using forest biodiversity as an example, we illustrate how one can combine ecological and institutional aspects of biodiversity conservation, thus facilitating environmentally sustainable regional development. In particular, we use regional gap analysis for identification of focal forest types, habitat modelling for ascertaining the functional connectivity of "green infrastructures", as tools for the horizontal gap analysis. For the vertical dimension we suggest how the social sciences can be used for assessing the success in the implementation of biodiversity policies in real landscapes by identifying institutional obstacles while implementing policies. We argue that this interdisciplinary approach could be applied in a whole range of other environments including other terrestrial biota and aquatic ecosystems where functional habitat connectivity, nonlinear response to habitat loss and a multitude of economic and social interests co-occur in the same landscape. 相似文献
72.
73.
Ana M. Martín González Juan Francisco Ornelas Bo Dalsgaard Ubaldo Márquez-Luna Carlos Lara 《Die Naturwissenschaften》2018,105(9-10):54
Recent studies on ecological networks have quantified the contribution of ecological, historical, and evolutionary factors on the structure of local communities of interacting species. However, the influence of species’ biogeographical traits, such as migratory habits or phylogeographical history, on ecological networks is poorly understood. Meta-networks, i.e., networks that cover large spatial extensions and include species not co-occurring locally, enable us to investigate mechanisms that operate at larger spatial scales such as migratory patterns or phylogeographical distributions, as well as indirect relationships among species through shared partners. Using a meta-network of hummingbird-plant interaction across Mexico, we illustrate the usefulness of this approach by investigating (1) how biogeographical and morphological factors associate with observed interactions and (2) how species-specific biogeographical characteristics associate with species’ network roles. Our results show that all studied hummingbird and plant species in the meta-network were interrelated, either directly or through shared partners. The meta-network was structured into modules, resulting from hummingbirds and plants interacting preferentially with subsets of species, which differed in biogeographical, and, to a lesser extent, morphological traits. Furthermore, migrants and hummingbirds from Nearctic, Transition, and widespread regions had a higher topological importance in the meta-network. Our study illustrates how meta-networks may contribute to our current knowledge on species’ biogeographical traits and biotic interactions, providing a perspective complementary to local-scale networks. 相似文献
74.
Chemical waste compositions are important for municipal solid waste management, as they determine the pollution potentials from different waste strategies. A representative dataset for chemical characteristics of individual waste fractions is frequently required to assess chemical waste composition, but it is usually reported in developed countries and not in developing countries. In this study, a dataset for Chinese waste was established through careful data screening and assessment, named as CN dataset. Meanwhile, a dataset for Danish waste (DK dataset) was also summarized based on previous studies. In order to quantitatively evaluate the reliabilities of CN and DK datasets, the chemical waste compositions in four Chinese cities were estimated by utilizing both of them, respectively. It is indicated that the usage of CN datasets led to significantly lower discrepancies from the actual values based on laboratory analysis in most cases. Within the datasets, the moisture contents of food waste, paper, textiles, and plastics, the carbon content of food waste, as well as the oxygen content of plastics would induce significant divergences, which should be paid special attention when gathering the information. In addition, the fractional waste compositions in China showed similar features with other developing countries but differ significantly with developed countries. Thus the above-mentioned conclusions could also be true in other developing countries. 相似文献
75.
O. Fuchs O. Lutz Ludwig Hopf F. Hund Kurt Kaehne Anders K. Orvin 《Die Naturwissenschaften》1936,24(21):331-336
76.
77.
Tommy Kristensen Anders Isberg Nielsen Anders Isak J?rgensen Kim N. Mouritsen Henrik Glenner Jens T. Christensen J?rgen Lützen Jens T. H?eg 《Marine Biology》2012,159(9):2015-2023
Male crabs infected by parasitic barnacles (Rhizocephala) are known to be morphologically feminized. Here, we investigate morphological chances in green crabs, Carcinus maenas, induced by the parasitic barnacle Sacculina carcini. Infected males acquire a broader, longer and segmented abdomen, fringed with marginal setae. Copulatory appendages and pereopods are reduced in length, and the chelae become smaller. The feminization show great individual variation. Males with scars from lost externae, the parasites reproductive organ situated under the abdomen, are less modified than males carrying an externa, and the feminization is more pronounced in smaller than in larger males. No super-feminization is evident in female crabs that remain morphologically unaffected by infection. The protective value of a parasitically induced enlargement of the male abdomen may constitute an adaptation that increases parasite longevity. The additional effects on male morphology are viewed as pleiotropic side effects of the main adaptive value of enlarging the abdomen. 相似文献
78.
Anders E. af Wåhlberg 《International journal of occupational safety and ergonomics》2013,19(2):159-171
Driver celeration (speed change) behavior of bus drivers measured a number of times was used to predict their culpable accidents over increasing time periods. It was found that predictive power was considerable (>.30 correlation) over 5 years of time with aggregated celeration (mean of repeated measurements) as independent variables, and there were also indications that power reached even further, although too low Ns made these results unreliable. Similarly, there were indications of even stronger correlations with increased aggregation of celeration values. The results were discussed in terms of the methodology needed to bring out such results, and the stability of accident-causing behavior over time. 相似文献
79.
Field application of animal manure is a major cause of odor nuisance in the local environment. Therefore, there is a need for methods for measuring the effect of technologies for reducing odor after manure application. In this work, chemical methods were used to identify key odorants from field application of pig manure based on experiments with surface application by trailing hoses and soil injection. Results from three consecutive years of field trials with full-scale equipment are reported. Methods applied were: membrane inlet mass spectrometry (MIMS), proton-transfer-reaction mass spectrometry (PTR-MS), gold-film hydrogen sulfide (H?S) detection, all performed on site, and thermal desorption gas chromatography with mass spectrometry (TD-GC/MS) based on laboratory analyses of field samples. Samples were collected from a static flux chamber often used for obtaining samples for dynamic olfactometry. While all methods were capable of detecting relevant odorants, PTR-MS gave the most comprehensive results. Based on odor threshold values, 4-methylphenol, H?S, and methanethiol are suggested as key odorants. Significant odorant reductions by soil injection were consistently observed in all trials. The flux chamber technique was demonstrated to be associated with critical errors due to compound instabilities in the chamber. This was most apparent for H?S, on a time scale of a few minutes, and on a longer time scale for methanethiol. 相似文献
80.
Bhawna Singh Anders H. Strømman Edgar Hertwich 《International Journal of Greenhouse Gas Control》2011,5(3):457-466
Hybrid life cycle assessment has been used to assess the environmental impacts of natural gas combined cycle (NGCC) electricity generation with carbon dioxide capture and storage (CCS). The CCS chain modeled in this study consists of carbon dioxide (CO2) capture from flue gas using monoethanolamine (MEA), pipeline transport and storage in a saline aquifer.Results show that the sequestration of 90% CO2 from the flue gas results in avoiding 70% of CO2 emissions to the atmosphere per kWh and reduces global warming potential (GWP) by 64%. Calculation of other environmental impacts shows the trade-offs: an increase of 43% in acidification, 35% in eutrophication, and 120–170% in various toxicity impacts. Given the assumptions employed in this analysis, emissions of MEA and formaldehyde during capture process and generation of reclaimer wastes contributes to various toxicity potentials and cause many-fold increase in the on-site direct freshwater ecotoxicity and terrestrial ecotoxicity impacts. NOx from fuel combustion is still the dominant contributor to most direct impacts, other than toxicity potentials and GWP. It is found that the direct emission of MEA contribute little to human toxicity (HT < 1%), however it makes 16% of terrestrial ecotoxicity impact. Hazardous reclaimer waste causes significant freshwater and marine ecotoxicity impacts. Most increases in impact are due to increased fuel requirements or increased investments and operating inputs.The reductions in GWP range from 58% to 68% for the worst-case to best-case CCS system. Acidification, eutrophication and toxicity potentials show an even large range of variation in the sensitivity analysis. Decreases in energy use and solvent degradation will significantly reduce the impact in all categories. 相似文献