7,197 research outputs found
Rate of lineage origin explains the diversity anomaly in the World’s mangrove vegetation
The contribution of nonecological factors to global patterns in diversity is evident when species richness differs between regions with similar habitats and geographic area. Mangrove environments in the Eastern Hemisphere harbor six times as many species of trees and shrubs as similar environments in the New World. Genetic divergence of mangrove lineages from terrestrial relatives, in combination with fossil evidence, suggests that mangrove diversity is limited by evolutionary transition into the stressful marine environment, the number of mangrove lineages has increased steadily over the Tertiary with little global extinction, and the diversity anomaly in mangrove vegetation reflects regional differences in the rate of origin of new mangrove lineages
The cost-efficiency of water-based marine emission abatement
Today about 90 per cent of the world’s trade is concluded by using ships. This entails that the seafaring is one of the main attempters for the poisonous greenhouse gases.
Through the globalization and the tendency to produce and sell goods all around the world, leads to wider use of ship transportation and hence increasing emissions.
According to this fact it is important to find ways to abate ship emissions. This is supported with stricter emission limits in the Baltic Sea. To meet these regulations,
vessels need to have installed an emission abatement system. In the range of this thesis the two water-based NOx abatement measures DWI and HAM are observed, especially regarding their cost-effectiveness.
To find a figure how many € per abated ton of NOx these technologies cost, a case study with two ships was made. One ship was retrofitted with a HAM system and the other ship was new build with DWI technology. The calculations were based on
figures found in literature and the ship owners.
In conclusion, the costs per abated ton of NOx vary greatly with the specific ship. For DWI they are in the range from 243,25 €/t to 928,08 €/t. The HAM system is not so cost-intensive it varies from 282,58 €/t to 378,46 €/t
Reasoning by analogy in the generation of domain acceptable ontology refinements
Refinements generated for a knowledge base often involve the learning of new knowledge to be added to or replace existing parts of a knowledge base. However, the justifiability of the refinement in the context of the domain (domain acceptability) is often overlooked. The work reported in this paper describes an approach to the generation of domain acceptable refinements for incomplete and incorrect ontology individuals through reasoning by analogy using existing domain knowledge. To illustrate this approach, individuals for refinement are identified during the application of a knowledge-based system, EIRA; when EIRA fails in its task, areas of its domain ontology are identified as requiring refinement. Refinements are subsequently generated by identifying and reasoning with similar individuals from the domain ontology. To evaluate this approach EIRA has been applied to the Intensive Care Unit (ICU) domain. An evaluation (by a domain expert) of the refinements generated by EIRA has indicated that this approach successfully produces domain acceptable refinements
Three-steps in one-pot: whole-cell biocatalytic synthesis of enantiopure (+)- and (−)-pinoresinol via kinetic resolution
Additional file 5. HPLC chromatograms of enantiomeric separations of reaction products. a Application of AtPrR2; b application of FiPLR. [3a] = (+)-pinoresinol 3a, [3b] = (−)-pinoresinol 3b, [4a] = (+)-lariciresinol 4a, [4b] = (−)-lariciresinol 4b, [5a] = (−)-secoisolariciresinol 5a
The response of neotropical dragonflies (Insecta: Odonata) to local and regional abiotic factors in small streams of the Amazon
Since the relative role of local and regional abiotic factors on the Odonata diversity in rainforest streams is still poorly understood, we evaluated the effects of these factors on adult Odonata (Insecta) from preserved and altered streams in the Amazonian region. Adult Odonata were sampled in 98 streams in the Eastern Amazon, Pará, Brazil. Six variables were used to measure local environmental factors: habitat integrity index; mean canopy over the channel; and four physical and chemical descriptors of the water. To measure regional environmental factors, six variables were also used: altitude gradient, three bioclimatic variables and two percentage forest variables. In partial redundancy analysis, both abiotic factors (local and regional) were important to explain the variation in the Odonata community. The Odonata community can be influenced by regional and local factors. The relationship between Odonata and the local (e.g., integrity, canopy cover, and physical and chemical descriptors of the water) and regional (e.g., bioclimatic and forest cover variables) environmental variables recorded in this study has important implications for the use of these organisms to monitor small streams of the Eastern Amazon. The scale at which habitat is measured is an important issue in community structuring studies considering the rapid environmental changes. It is of great importance to consider the different scales in studies assessing community structure, once an adequate habitat must meet the ecological needs of all stages of the life of the Odonata.Funding Agency
National Council for Scientific and Technological Development (CNPq)
CNPq Amazonian Biodiversity and Land Use project
CNPq 574008/2008-0
Brazilian Agricultural Research Company-EMBRAPA
SEG: 02.08.06.005.00
Darwin Initiative, United Kingdom
17-023
Nature Conservancy and Natural Environment Research Council (NERC)
NE/F01614X/1
NE/G000816/1
National Council for Scientific and Technological Development (CNPq)
307597/2016-4
Portuguese Foundation for Science and Technology
UID/Multi/04326/2019
PROPESP/UFPA through Edital 01/2018 (Programa de Apoio a Publicacao Qualificada-PAPQ)info:eu-repo/semantics/publishedVersio
Postglacial migration supplements climate in determining plant species ranges in Europe
The influence of dispersal limitation on species ranges remains controversial. Considering the dramatic impacts of the last glaciation in Europe, species might not have tracked climate changes through time and, as a consequence, their present-day ranges might be in disequilibrium with current climate. For 1016 European plant species, we assessed the relative importance of current climate and limited postglacial migration in determining species ranges using regression modelling and explanatory variables representing climate, and a novel species-specific hind-casting-based measure of accessibility to postglacial colonization. Climate was important for all species, while postglacial colonization also constrained the ranges of more than 50 per cent of the species. On average, climate explained five times more variation in species ranges than accessibility, but accessibility was the strongest determinant for one-sixth of the species. Accessibility was particularly important for species with limited long-distance dispersal ability, with southern glacial ranges, seed plants compared with ferns, and small-range species in southern Europe. In addition, accessibility explained one-third of the variation in species' disequilibrium with climate as measured by the realized/potential range size ratio computed with niche modelling. In conclusion, we show that although climate is the dominant broad-scale determinant of European plant species ranges, constrained dispersal plays an important supplementary role
Strong paleoclimatic legacies in current plant functional diversity patterns across Europe
Numerous studies indicate that environmental changes during the late Quaternary have elicited long‐term disequilibria between species diversity and environment. Despite its importance for ecosystem functioning, the importance of historical environmental conditions as determinants of FD (functional diversity) remains largely unstudied. We quantified the geographic distributions of plant FD (richness and dispersion) across Europe using distribution and functional trait information for 2702 plant species. We then compared the importance of historical and contemporary factors to determine the relevance of past conditions as predictors of current plant FD in Europe. For this, we compared the strength of the relationships between FD with temperature and precipitation stability since the LGM (Last Glacial Maximum), accessibility to LGM refugia, and contemporary environmental conditions (climate, productivity, soil, topography, and land use). Functional richness and dispersion exhibited geographic patterns with strong associations to the environmental history of the region. The effect size of accessibility to LGM refugia and climate stability since the LGM was comparable to that of the contemporary predictors. Both functional richness and dispersion increased with temperature stability since the LGM and accessibility to LGM refugia. Functional richness' geographic pattern was primarily associated with accessibility to LGM refugia growing degree‐days, land use heterogeneity, diversity of soil types, and absolute minimum winter temperature. Functional dispersion's geographic pattern was primarily associated with accessibility to LGM refugia growing degree‐days and absolute minimum winter temperature. The high explained variance and model support of historical predictors are consistent with the idea that long‐term variability in environmental conditions supplements contemporary factors in shaping FD patterns at continental scales. Given the importance of FD for ecosystem functioning, future climate change may elicit not just short‐term shifts in ecosystem functioning, but also long‐term functional disequilibria
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