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131.
Vulnerability assessment is increasingly recognised as a starting point to identify climate adaptation needs and improve adaptive capacity. However, vulnerability assessments are challenging because of the complexity of multifaceted biophysical, human and institutional factors, interacting at different scales and levels within socio-ecological systems. Using a participatory approach across levels and genders, this paper explores the vulnerability of livestock- and forest-based livelihoods to climate variability and change in Lake Faguibine, northern Mali, where drastic ecological, political and social changes have occurred. Our results show that the distribution of vulnerabilities within livelihoods and groups shifted when the ecosystem evolved from a lake to a forest. New vulnerability drivers have emerged, related to resources availability, access and power relations. In addition, political interests and psychological barriers hinder the local transition to an equitable and sustainable use of forest ecosystem services. Divergent perceptions, social identities, interests and power explained why different actors—governmental and non-governmental, men and women, local, sub-national and national—differed in their vulnerability assessments. This is exemplified in the way actors at different levels and of different gender analysed the effects of herders’ mobility and in the way women analysed men’s migration. This case study confirms the need for participatory and gender-sensitive vulnerability assessments across different scales and levels that consider the interaction between socio-ecological systems and the dynamics and distribution of vulnerability across different social sub-systems. 相似文献
132.
A cover with capillary barrier effects (CCBE) was constructed in 1998 on the abandoned Lorraine mine tailings impoundment to limit the generation of acid mine drainage. The Ministry of Natural Resources and Fauna of Quebec (MRNF) is responsible for the site and for all restoration works on it, including CCBE construction. The CCBE is made up of three layers: a 0.3-m layer of sand used as a support and capillary break layer; a moisture-retaining layer with a thickness of 0.5 m (this layer is constructed of a nonplastic silt); and a 0.3-m sand and gravel layer on top. The main objective of the CCBE is to maintain one (or more) of the layers at a high degree of water saturation to impede oxygen migration and acid generation. Vegetation succession on the Lorraine CCBE results in an improvement in soil conditions, leading to the installation of deep-rooted species, which could represent a risk to CCBE long-term performance. Hence, the characterization of vegetation succession is an important aspect of the monitoring strategy for the Lorraine CCBE. Species occurrence was documented, and depth of tree roots was measured by excavation on a regular basis. Eight functional groups of plants were identified; herbaceous plants were the most abundant ecological plant groups. Tree ring counts confirmed that tree colonization started the year of CCBE construction (1999). Of the 11 tree species identified, the most abundant were poplar (Populus spp.), paper birch (Betula payrifera Marsh.), black spruce (Picea mariana Mill.), and willow (Salix spp.). Significant differences in occurrence related to environmental conditions were observed for most functional groups. Root excavation showed that tree roots exceeded the depth of the protective layer and started to reach the moisture-retaining layer; in 2008, root average depth was 0.4 m and the maximal root depth was 1.7 m. 相似文献
133.
This work presents an unconventional procedure for the recovery of spent Al-rich caustic soda solutions from the pickling of dies for the production of aluminium extrusions. Caustic soda was regenerated at roughly 70%, by precipitating aluminate, after addition of a silica source, in the form of zeolite A, a microporous material that is widely used in many technological sectors. It was shown that the process is reliable and can be repeated for several cycles, provided the concentration of the caustic soda solution is suitably restored. The by-product obtained, zeolite A, proved to be a high-grade material with performance as a cation exchanger and physical sorbent that is certainly comparable to that reported in literature (e.g., cation exchange capacity equal to 5.14 meq g(-1) vs. 5.48 meq g(-1) and water vapour adsorption capacity of 26.5% vs. 27.6% at 16 torr and 298 K). The economics of the process, although not examined yet, would appear generally favourable, considering that zeolite A is a valuable by-product which widely covers the costs for the recovery of the spent solutions. There are, therefore, significant prospects for the use of zeolite A, particularly as a builder in detergent formulation. 相似文献
134.
Pienkoß Fabian Abis Marco Bruno Martina Grönholm Raul Hoppe Michel Kuchta Kerstin Fiore Silvia Simon Franz-Georg 《Journal of Material Cycles and Waste Management》2022,24(1):364-377
Journal of Material Cycles and Waste Management - This work is aimed at exploring the recovery of heavy metals from the fine fraction of solid waste incineration bottom ash. For this study,... 相似文献
135.
Soares Jéssica Maria Alexandre da Silva Júnior Elenildo Dário Oliveira de Veras Bruno Yara Ricardo de Albuquerque Priscilla Barbosa Sales de Souza Marthyna Pessoa 《Journal of Polymers and the Environment》2022,30(1):217-231
Journal of Polymers and the Environment - Bioactive biodegradable films are emerging biomaterials in the food packaging field. This study aims to investigate the effect of different Cenostigma... 相似文献
136.
Battisti Sabrina Scaramozzino Paola Boselli Carlo Busico Fabio Berretta Sesto Sala Marcello Neri Bruno 《Environmental science and pollution research international》2022,29(46):69424-69438
Environmental Science and Pollution Research - This study reports the data of polychlorinated dibenzo-p-dioxins (PCDDs), -furans (PCDFs), and polychlorinated biphenyls dioxin-like (dl PCBs)... 相似文献
137.
Heiko Schmaljohann Felix Liechti Bruno Bruderer 《Behavioral ecology and sociobiology》2009,63(11):1609-1619
Meteorological conditions influence strongly the energy and water budget of birds. By adjusting their flights spatially and
temporally with respect to these conditions, birds can reduce their energy expenditure and water loss considerably. By radar,
we quantified songbird migration across the western Sahara in spring and autumn. There autumn migrants face the trade-off
between (a) favorable winds combined with hot and dry air at low altitudes and (b) unfavorable winds combined with humid and
cold air higher up. Thus, it can be tested whether birds may chose altitudes to minimize water loss instead of energy expenditure.
We predicted optimal flight altitudes with respect to water loss and energy expenditure based on a physiological flight model
when crossing the western Sahara and compared these model predictions spatially and temporally with measured songbird densities.
The model aiming for minimal water consumption predicted a mean flight altitude of 3,400 m under autumn conditions. However,
64% of the nocturnal songbird migration flew at altitudes below 1,000 m above ground level profiting from tailwind. This preference
for tailwind in autumn, despite the hot and dry air, emphasizes the importance of energy savings and diminishes the significance
of possible water stress for the selection of flight altitude. Nevertheless, during daytime, high energy expenditure due to
air turbulences and water loss due to warmer air and direct solar radiation prevent songbirds from prolonging their nocturnal
flights regularly into the day. Birds crossing the Sahara save water by nocturnal flights and diurnal rests. 相似文献
138.
Anna Gagliardo Maria Savini Angelo De Santis Giacomo Dell’Omo Paolo Ioalè 《Behavioral ecology and sociobiology》2009,64(2):289-296
Some authors have proposed that homing pigeons are able to correct the error in orientation following a phase-shift treatment
by using the magnetic compass reference. They reported that clock-shifted pigeons bearing magnets display a greater deflection
compared to magnetically unmanipulated clock-shifted birds. However, this hypothesis tested by recording pigeons’ vanishing
bearings has led to contradictory results. The present study reports pigeons’ tracks recorded with a GPS and shows that clock-shifted
pigeons bearing magnets displayed a greater deviation through the whole route compared to the magnetically unmanipulated shifted
pigeons. Moreover, the analysis of the tracks shows that the birds belonging to both experimental groups stop in coincidence
with their subjective night. When re-starting their journey, the birds corrected the clock-shift induced error in orientation,
but the magnetically manipulated pigeons were less efficient in doing so. Our results are consistent with the hypothesis that
homing pigeons released from unfamiliar location re-orient after clock shift by using the magnetic compass. 相似文献
139.
Quantification of copepod gut content by differential length amplification quantitative PCR (dla-qPCR) 总被引:1,自引:0,他引:1
Christofer Troedsson Paolo Simonelli Verena Nägele Jens C. Nejstgaard Marc E. Frischer 《Marine Biology》2009,156(3):253-259
Quantification of feeding rates and selectivity of zooplankton is vital for understanding the mechanisms structuring marine
ecosystems. However, methodological limitations have made many of these studies difficult. Recently, molecular based methods
have demonstrated that DNA from prey species can be used to identify zooplankton gut contents, and further, quantitative gut
content estimates by quantitative PCR (qPCR) assays targeted to the 18S rRNA gene have been used to estimate feeding rates
in appendicularians and copepods. However, while standard single primer based qPCR assays were quantitative for the filter
feeding appendicularian Oikopleura dioica, feeding rates were consistently underestimated in the copepod Calanus finmarchicus. In this study, we test the hypothesis that prey DNA is rapidly digested after ingestion by copepods and describe a qPCR-based
assay, differential length amplification qPCR (dla-qPCR), to account for DNA digestion. The assay utilizes multiple primer
sets that amplify different sized fragments of the prey 18S rRNA gene and, based on the differential amplification of these
fragments, the degree of digestion is estimated and corrected for. Application of this approach to C. finmarchicus fed Rhodomonas marina significantly improved quantitative feeding estimates compared to standard qPCR. The development of dla-qPCR represents a
significant advancement towards a quantitative method for assessing in situ copepod feeding rates without involving cultivation-based
manipulation. 相似文献
140.
This study presents the results of experimental Fenton-like treatments conducted on marine sediment slurries (2g sediment vs. 20 ml liquid). The sediment was collected in a harbor situated in a high density industrial area, characterized by a great hydrocarbon C>12 and PAHs contamination. The investigated parameters were: the H(2)O(2) dose, the reagent's pH and the effect of a phosphate salt and ferrous iron addition. To evaluate sediment's characteristics COD, particle size, thermogravimetric and differential thermal analyses were performed under N(2) and O(2) atmosphere while dissolved organic carbon and COD analyses were performed on the filtrate. Results indicate that the treatment was able to change the organic matter to a less hydrophobic state, to destroy part of the organic carbon (up to 78% decrease of the 200-400 degrees C labile organic matter), to lower the COD of the sediment (60% COD removal maximum) and to increase the cumulated distribution undersize. In addition as the treated sediment showed easier-to-handle characteristics, reduced caking and lower aggregation capacity, the modified Fenton treatment could also be considered a pre-treatment of a successive thermal treatment. 相似文献