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81.
Hermosilla Edward Schalchli Heidi Mutis Ana Diez María Cristina 《Environmental science and pollution research international》2017,24(27):21984-21996
Environmental Science and Pollution Research - Lignin is one of the main barriers to obtaining added-value products from cellulosic fraction of lignocellulosic biomass due to its random aromatic... 相似文献
82.
The paper shows how sustainability questions relate to the local space. The local place is not a static entity, but a dynamic one, undergoing constant changes, and it is the rapid social and material processes within the given local situation that is a challenge for the Chinese villages and their integrity. The following article considers the cohesion between the dwellers' emotional co-ownership of their local space and the sustainability process as a driving force in social, economic and ecological development. We bring together the classification of the seven fields of encounter, which were developed out of the empirical data of the Chinese case study villages, and sustainability oriented management considerations for all levels of this concept. We do not pretend to know the solutions, but describe a set of interrelated fields that can be anchor points for placing the solutions and show in which fields action and intervention is possible. In our concept of sustainability, every spatial field has its special meaning, needs special measures and policies and has different connotations to concepts like responsibility, family values or communication systems. We see the social sustainability process as a support for the empowerment of the local dwellers, and the SUCCESS research has encouraged the villages to find suitable sustainability oriented solutions for their natural and societal situation. Before entering the discussion about the chances and potential of a sustainability approach for the Chinese villages, it is first necessary to accept the fact that rural villages play a primordial role in Chinese society and that their potential can strengthen future pathways for China. 相似文献
83.
84.
Chinese villages and their sustainable future: the European Union-China-Research Project "SUCCESS" 总被引:2,自引:0,他引:2
Dumreicher H 《Journal of environmental management》2008,87(2):204-215
China has 800,000 villages—one person out of seven on the globe is living in a Chinese rural settlement. Yet the global discussions about the situation in China is currently characterised by a disproportionate focus on the development of towns and until now circumstances have generally been neglected in the rural areas, where 70% of the Chinese population is still living. Within the 5 years of the SUCCESS project research, this set of actual problems has been considered and analysed under the principle of sustainability: “What to maintain?” “What to change?” were the overall research questions asked in the SUCCESS project; the researchers were looking for answers under a sustainability regime, respecting the need to raise the quality of life in the villages. Several interweaving processes were used to achieve results: the inter-disciplinary research process between many areas of expertise, the trans-disciplinary process between the researchers and the Chinese villagers, and a negotiation process that made the connection between these two processes. 相似文献
85.
Flume experiments were conducted with rigid and flexible model vegetation to study the structure of coherent vortices (a manifestation
of the Kelvin–Helmholtz instability) and vertical transport in shallow vegetated shear flows. The vortex street in a vegetated
shear layer creates a pronounced oscillation in the velocity profile, with the velocity near the top of a model canopy varying
by a factor of three during vortex passage. In turn, this velocity oscillation drives the coherent waving of flexible canopies.
Relative to flows over rigid vegetation, the oscillation in canopy geometry has the effect of decreasing the amount of turbulent
vertical momentum transport in the shear layer. Using a waving plant to determine phase in the vortex cycle, each vortex is
shown to consist of a strong sweep at its front (during which the canopy is most deflected), followed by a weak ejection at
its rear (when the canopy height is at a maximum). Whereas in unobstructed mixing layers the vortices span the entire layer,
they encompass only 70% of the flexibly obstructed shear layer studied here. 相似文献
86.
It has been suggested that actively expressed genes are primarily located in early replicating bands. This hypothesis is supported by cytogenetic and pregnancy outcome data from four consecutive cases of prenatally detected de novo marker chromosomes. Two fetuses with major anomalies had large early replicating bands, while the marker in a third phenotypically normal fetus was late replicating. In the fourth case, a ring marker chromosome had only a small early replicating region. Pregnancy termination was elected. While no structural malformations were apparent, potential intellectual function in this case remains unresolved. An understanding of the relationship between genomic organization and chromosome banding is critical in counseling for prenatally detected de novo marker chromosomes. Replicational banding is particularly helpful in recognizing genes that may be actively expressed and result in developmental abnormality. 相似文献
87.
Continuous automated imaging-in-flow cytometry for detection and early warning of Karenia brevis blooms in the Gulf of Mexico 总被引:1,自引:0,他引:1
Lisa Campbell Darren W. Henrichs Robert J. Olson Heidi M. Sosik 《Environmental science and pollution research international》2013,20(10):6896-6902
Monitoring programs for harmful algal blooms (HABs) typically rely on time-consuming manual methods for identification and enumeration of phytoplankton, which make it difficult to obtain results with sufficient temporal resolution for early warning. Continuous automated imaging-in-flow by the Imaging FlowCytobot (IFCB) deployed at Port Aransas, TX has provided early warnings of six HAB events. Here we describe the progress in automating this early warning system for blooms of Karenia brevis. In 2009, manual inspection of IFCB images in mid-August 2009 provided early warning for a Karenia bloom that developed in mid-September. Images from 2009 were used to develop an automated classifier that was employed in 2011. Successful implementation of automated file downloading, processing and image classification allowed results to be available within 4 h after collection and to be sent to state agency representatives by email for early warning of HABs. No human illness (neurotoxic shellfish poisoning) has resulted from these events. In contrast to the common assumption that Karenia blooms are near monospecific, post-bloom analysis of the time series revealed that Karenia cells comprised at most 60–75 % of the total microplankton. 相似文献
88.
Norbert V. Heeb Daniel Zindel Heidi Graf Valeria Azara W. Bernd Schweizer Birgit Geueke Hans-Peter E. Kohler Peter Lienemann 《Chemosphere》2013,90(6):1911-1919
The haloalkane dehalogenase LinB from Sphingobium indicum B90A converts β-hexachlorocyclohexane (β-HCH), the most persistent HCH stereoisomer, to mono- and dihydroxylated metabolites. Recently, we reported that LinB also transforms α-, β- and γ-hexabromocyclododecanes (HBCDs), which are structurally related to HCHs. Here, we show that LinB catalyzes the hydroxylation of δ-HBCD to two pentabromocyclododecanols (PBCDOHs) and two tetrabromocyclododecadiols (TBCDDOHs). The stereochemistry of this enzymatic transformation was deduced from XRD crystal structure data of the substrate δ-HBCD and α2-PBCDOH, one of the biotransformation products. Five stereocenters of δ-HBCD are unchanged but the one at C6 is converted to an alcohol with inversion from S- to R-configuration in a nucleophilic, SN2-like substitution reaction. Only α2-PBCDOH with the 1R,2R,5S,6R,9R,10S-configuration is obtained but not its enantiomer. With only two of the 64 PBCDOHs formed, these transformations indeed are regio- and stereoselective. A conformational analysis revealed that the triple-turn motive, which is predominant in δ-HBCD and in several other HBCD stereoisomers, is also found in the product. This shows that LinB preferentially converted reactive bromine atoms but not those in the conserved triple-turn motive. The widespread contamination with HCHs triggered the bacterial evolution of dehalogenases which acquired the ability to convert these pollutants and their metabolites. We here demonstrate that LinB of S. indicum also transforms HBCDs regio- and stereoselectively following a similar mechanism. 相似文献
89.
Keith H. Nislow Francis J. Magilligan Heidi Fassnacht Doug Bechtel Ana Ruesink 《Journal of the American Water Resources Association》2002,38(6):1533-1548
ABSTRACT: Understanding the effects of dams on the inundation regime of natural floodplain communities is critical for effective decision making on dam management or dam removal. To test the implications of hydrologic alteration by dams for floodplain natural communities, we conducted a combined field and modeling study along two reaches in the Connecticut River Rapids Macrosite (CRRM), one of the last remaining flowing water sections of the Upper Connecticut River. We surveyed multiple channel cross sections at both locations and concurrently identified and surveyed the elevations of important natural communities, native species of concern, and nonnative invasive species. Using a hydrologic model, HEC‐RAS, we routed estimated pre‐and post‐impoundment discharges of different design recurrence intervals (two year through 100 year floods) through each reach to establish corresponding reductions in elevation and effective wetted perimeter following post‐dam discharge reductions. By comparing (1) the frequency and duration of flooding of these surfaces before and after impoundment and (2) the total area flooded at different recurrence intervals, our goal was to derive a spatially explicit assessment of hydrologic alteration, directly relevant to natural floodplain communities. Post‐impoundment hydrologic alteration profoundly affected the subsequent inundation regime, and this impact was particularly true of higher floodplain terraces. These riparian communities, which were flooded, on average, every 20 to 100 years pre‐impoundment, were predicted to flood at 100 ? 100 year intervals, essentially isolating them completely from riverine influence. At the pre‐dam five to ten year floodplain elevations, we observed smaller differences in predicted flood frequency but substantial differences in the total area flooded and in the average flood duration. For floodplain forests in the Upper Connecticut River, this alteration by impoundment suggests that even if other stresses facing these communities (human development, invasive exotics) were alleviated, this may not be sufficient to restore intact natural communities. More generally, our approach provides a way to combine site specific variables with long term gage records in assessing the restorative potential of dam removal. 相似文献
90.
Jeanne L. Nel Dirk J. Roux Amanda Driver Liesl Hill Ashton C. Maherry Kate Snaddon Chantel R. Petersen Lindie B. Smith‐Adao Heidi Van Deventer Belinda Reyers 《Conservation biology》2016,30(1):176-188
Knowledge co‐production and boundary work offer planners a new frame for critically designing a social process that fosters collaborative implementation of resulting plans. Knowledge co‐production involves stakeholders from diverse knowledge systems working iteratively toward common vision and action. Boundary work is a means of creating permeable knowledge boundaries that satisfy the needs of multiple social groups while guarding the functional integrity of contributing knowledge systems. Resulting products are boundary objects of mutual interest that maintain coherence across all knowledge boundaries. We examined how knowledge co‐production and boundary work can bridge the gap between planning and implementation and promote cross‐sectoral cooperation. We applied these concepts to well‐established stages in regional conservation planning within a national scale conservation planning project aimed at identifying areas for conserving rivers and wetlands of South Africa and developing an institutional environment for promoting their conservation. Knowledge co‐production occurred iteratively over 4 years in interactive stake‐holder workshops that included co‐development of national freshwater conservation goals and spatial data on freshwater biodiversity and local conservation feasibility; translation of goals into quantitative inputs that were used in Marxan to select draft priority conservation areas; review of draft priority areas; and packaging of resulting map products into an atlas and implementation manual to promote application of the priority area maps in 37 different decision‐making contexts. Knowledge co‐production stimulated dialogue and negotiation and built capacity for multi‐scale implementation beyond the project. The resulting maps and information integrated diverse knowledge types of over 450 stakeholders and represented >1000 years of collective experience. The maps provided a consistent national source of information on priority conservation areas for rivers and wetlands and have been applied in 25 of the 37 use contexts since their launch just over 3 years ago. When framed as a knowledge co‐production process supported by boundary work, regional conservation plans can be developed into valuable boundary objects that offer a tangible tool for multi‐agency cooperation around conservation. Our work provides practical guidance for promoting uptake of conservation science and contributes to an evidence base on how conservation efforts can be improved. 相似文献