SwePub
Sök i SwePub databas

  Utökad sökning

Träfflista för sökning "WFRF:(Les K) "

Sökning: WFRF:(Les K)

  • Resultat 1-10 av 13
Sortera/gruppera träfflistan
   
NumreringReferensOmslagsbildHitta
1.
  • 2021
  • swepub:Mat__t
  •  
2.
  •  
3.
  •  
4.
  •  
5.
  • Bremer, Kåre, et al. (författare)
  • An ordinal classification for the families of flowering plants
  • 1998
  • Ingår i: ANNALS OF THE MISSOURI BOTANICAL GARDEN. - : MISSOURI BOTANICAL GARDEN. - 0026-6493. ; 85:4, s. 531-553
  • Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
    • Recent cladistic analyses are revealing the phylogeny of flowering plants in increasing detail, and there is support for the monophyly of many major groups above the family level. With many elements of the major branching sequence of phylogeny established
  •  
6.
  •  
7.
  • Dessne, Petter, et al. (författare)
  • OTEC matters 2015
  • 2015
  • Rapport (övrigt vetenskapligt/konstnärligt)abstract
    • For mankind as a whole, and in many respects, the world is becoming a better place each year. In both rich and poor countries the standard of living has improved steadily for a very long time. This progress has a serious drawback, the negative effects on Earth’s climate. It is clear that the only way we can live sustainably is by consuming much less. However, this is not enough: there is an undeniable need for new energy sources. As the world’s population grows, many countries will also face more severe shortages of food and of fresh, disease-free water. Most developing countries are situated in tropical regions and are therefore hit hard by increasing tropical storms and similar weather-based disasters, adding to these problems. Ocean Thermal Energy Conversion (OTEC) technology has been proven to be an ideal candidate for addressing and resolving all of these problems for small island developing states (SIDS), and a few months ago, the EU set aside€72 million euros for constructing OTEC plants outside Martinique. Built on a much larger scale, OTEC can, as the only technology known to man, supply the world with its total energy and fresh water needs, increase seafood production many times over, and cooling off parts of the sea surface when they become too hot – all this without any atmospheric emissions. Thus, it is with great excitement that this very first issue of the only journal dedicated to OTEC is being published. The publication covers many facets of OTEC and related matters, such as OTEC technology, sustainability including gender and other social studies, renewable energy, marine biology, metallurgy, and research on developing countries. The publication is aimed at two different audiences, scientists directly or indirectly involved with OTEC technology, and a more diverse group of people consisting of scientists from non-technical fields, industry people, politicians, investors, educators, and more. This volume is published as part of the publication series of the University of Borås, a progressive Swedish university with a high interest in and knowledge about sustainability.
  •  
8.
  • Downing, Andrea S., et al. (författare)
  • Coupled human and natural system dynamics as key to the sustainability of Lake Victoria's ecosystem services
  • 2014
  • Ingår i: Ecology and Society. - 1708-3087. ; 19:4, s. 31-
  • Tidskriftsartikel (refereegranskat)abstract
    • East Africa's Lake Victoria provides resources and services to millions of people on the lake's shores and abroad. In particular, the lake's fisheries are an important source of protein, employment, and international economic connections for the whole region. Nonetheless, stock dynamics are poorly understood and currently unpredictable. Furthermore, fishery dynamics are intricately connected to other supporting services of the lake as well as to lakeshore societies and economies. Much research has been carried out piecemeal on different aspects of Lake Victoria's system; e.g., societies, biodiversity, fisheries, and eutrophication. However, to disentangle drivers and dynamics of change in this complex system, we need to put these pieces together and analyze the system as a whole. We did so by first building a qualitative model of the lake's social-ecological system. We then investigated the model system through a qualitative loop analysis, and finally examined effects of changes on the system state and structure. The model and its contextual analysis allowed us to investigate system-wide chain reactions resulting from disturbances. Importantly, we built a tool that can be used to analyze the cascading effects of management options and establish the requirements for their success. We found that high connectedness of the system at the exploitation level, through fisheries having multiple target stocks, can increase the stocks' vulnerability to exploitation but reduce society's vulnerability to variability in individual stocks. We describe how there are multiple pathways to any change in the system, which makes it difficult to identify the root cause of changes but also broadens the management toolkit. Also, we illustrate how nutrient enrichment is not a self-regulating process, and that explicit management is necessary to halt or reverse eutrophication. This model is simple and usable to assess system-wide effects of management policies, and can serve as a paving stone for future quantitative analyses of system dynamics at local scales.
  •  
9.
  • Jønsson, Knud A., et al. (författare)
  • Biogeographical history of cuckoo‐shrikes (Aves: Passeriformes) : transoceanic colonization of Africa from Australo-Papua
  • 2010
  • Ingår i: Journal of Biogeography. - : Wiley. - 0305-0270 .- 1365-2699. ; 37:9, s. 1767-1781
  • Tidskriftsartikel (refereegranskat)abstract
    • Aim Cuckoo-shrikes and allies (Campephagidae) form a radiation of birds widely distributed in the Indo-Pacific and Africa. Recent studies on the group have been hampered by poor taxon sampling, causing inferences about systematics and biogeography to be rather speculative. With improved taxon sampling and analyses within an explicit spatiotemporal framework, we elucidate biogeographical patterns of dispersal and diversification within this diverse clade of passerine birds. Location Africa, Asia, Australo-Papua, the Pacific, the Philippines and Wallacea. Methods We use model-based phylogenetic methods (MrBayes and garli) to construct a phylogenetic hypothesis of the core Campephagidae (Campephagidae with the exclusion of Pericrocotus). The phylogeny is used to assess the biogeographical history of the group with a newly developed Bayesian approach to dispersal-vicariance analysis (Bayes-diva). We also made use of a partitioned beast analysis, with several calibration points taken from island ages, passerine mitochondrial substitution rates and secondary calibration points for passerine birds, to assess the timing of diversification and dispersal. Results We present a robust molecular phylogeny that includes all genera and 84% of the species within the core Campephagidae. Furthermore, we estimate divergence dates and ancestral area relationships. We demonstrate that Campephagidae originated in Australo-Papua with a single lineage (Pericrocotus) dispersing to Asia early. Later, there was further extensive transoceanic dispersal from Australo-Papua to Africa involving lineages within the core Campephagidae radiation. Main conclusions The phylogenetic relationships, along with the results of the ancestral area analysis and the timing of dispersal events, support a transoceanic dispersal scenario from Australo-Papua to Africa by the core Campephagidae. The sister group to core Campephagidae, Pericrocotus, dispersed to mainland Asia in the late Oligocene. Asia remained uncolonized by the core Campephagidae until the Pliocene. Transoceanic dispersal is by no means an unknown phenomenon, but our results represent a convincing case of colonization over a significant water gap of thousands of kilometres from Australo-Papua to Africa.
  •  
10.
  • Jønsson, Knud A, et al. (författare)
  • Explosive avian radiations and multi-directional dispersal across Wallacea : evidence from the Campephagidae and other Crown Corvida (Aves).
  • 2008
  • Ingår i: Molecular Phylogenetics and Evolution. - : Elsevier BV. - 1055-7903 .- 1095-9513. ; 47:1, s. 221-36
  • Tidskriftsartikel (refereegranskat)abstract
    • The systematic relationships among avian families within Crown Corvida have been poorly studied so far and as such been of limited use for biogeographic interpretations. The group has its origin in Australia and is thought to have colonized Africa and the New World via Asia beginning some 35 Mya when terranes of Australian origin approached Asian landmasses. Recent detailed tectonic mapping of the origin of land masses in the region around Wallace's line have revealed a particularly complex movement of terranes over the last 20-30 Myr. Thus the biogeographic dispersal pattern of Crown Corvida is a particularly exciting case for linking vicariance and dispersal events with Earth history. Here we examine phylogenetic affinities among 72 taxa covering a broad range of genera in the basal radiations within Crown Corvida with an emphasis on Campephagidae and Pachycephalidae. Bayesian analyses of nuclear DNA sequence data identified the family Campephagidae as monophyletic but the large genus Coracina is not. Within the family Pachycephalidae the genera Pachycephala and Colluricincla are paraphyletic with respect to each other. The resulting phylogeny suggests that patterns of dispersal across Wallace's line are complex and began at least 25 Mya. We find evidence of explosive radiations and multi-directional dispersal within the last 10 Myr, and three independent long distance ocean dispersal events between Wallacea and Africa at 10-15 Mya. Furthermore, the study reveals that in the Campephagidae a complex series of dispersal events rather than vicariance is the most likely explanation for the current biogeographic pattern in the region.
  •  
Skapa referenser, mejla, bekava och länka
  • Resultat 1-10 av 13

Kungliga biblioteket hanterar dina personuppgifter i enlighet med EU:s dataskyddsförordning (2018), GDPR. Läs mer om hur det funkar här.
Så här hanterar KB dina uppgifter vid användning av denna tjänst.

 
pil uppåt Stäng

Kopiera och spara länken för att återkomma till aktuell vy