Staff Publications

Staff Publications

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    'Staff publications' is the digital repository of Wageningen University & Research

    'Staff publications' contains references to publications authored by Wageningen University staff from 1976 onward.

    Publications authored by the staff of the Research Institutes are available from 1995 onwards.

    Full text documents are added when available. The database is updated daily and currently holds about 240,000 items, of which 72,000 in open access.

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    What determines plant species diversity in Central Africa?
    Proosdij, Andreas S.J. van - \ 2017
    Wageningen University. Promotor(en): M.S.M. Sosef, co-promotor(en): N. Raes; J.J. Wieringa. - Wageningen : Wageningen University - ISBN 9789463436618 - 161
    plants - biodiversity - species diversity - species - distribution - biogeography - central africa - biosystematics - tropical rain forests - modeling - planten - biodiversiteit - soortendiversiteit - soorten - distributie - biogeografie - centraal-afrika - biosystematiek - tropische regenbossen - modelleren

    Planet Earth hosts an incredible biological diversity. Estimated numbers of species occurring on Earth range from 5 to 11 million eukaryotic species including 400,000-450,000 species of plants. Much of this biodiversity remains poorly known and many species have not yet been named or even been discovered. This is not surprising, as the majority of species is known to be rare and ecosystems are generally dominated by a limited number of common species.

    Tropical rainforests are the most species-rich terrestrial ecosystems on Earth. The general higher level of species richness is often explained by higher levels of energy near the Equator (latitudinal diversity gradient). However, when comparing tropical rainforest biomes, African rainforests host fewer plant species than either South American or Asian ones. The Central African country of Gabon is situated in the Lower Guinean phytochorical region. It is largely covered by what is considered to be the most species-rich lowland rainforest in Africa while the government supports an active conservation program. As such, Gabon is a perfect study area to address that enigmatic question that has triggered many researchers before: “What determines botanical species richness?”.

    In the past 2.5 million years, tropical rainforests have experienced 21 cycles of global glaciations. They responded to this by contracting during drier and cooler glacials into larger montane and smaller riverine forest refugia and expanding again during warmer and wetter interglacials. The current rapid global climate change coupled with change of land use poses new threats to the survival of many rainforest species. The limited availability of resources for conservation forces governments and NGOs to set priorities. Unfortunately, for many plant species, lack of data on their distribution hampers well-informed decision making in conservation.

    Species distribution models (SDMs) offer opportunities to bridge at least partly this knowledge gap. SDMs are correlative models that infer the spatial distribution of species using only a limited set of known species occurrence records coupled with high resolution environmental data. SDMs are widely applied to study the past, present and future distribution of species, assess the risk of invasive species, infer patterns of species richness and identify hotspots, as well as to assess the impact of climate change. The currently available methods form a pipeline, with which data are selected and cleaned, models selected, parameterized, evaluated and projected to other areas and climatic scenarios, and biodiversity patterns are computed from these SDMs. In this thesis, SDMs of all Gabonese plant species were generated and patterns of species richness and of weighted endemism were computed (chapter 4 & 5).

    Although this pipeline enables the rapid generation of SDMs and inferring of biodiversity patterns, its effective use is limited by several matters of which three are specifically addressed in this thesis. Not knowing the true distribution limits the opportunities to assess the accuracy of models and assess the impact of assumptions and limitations of SDMs. The use of simulated species has been advocated as a method to systematically assess the impact of specific matters of SDMs (virtual ecologist). Following this approach, in chapter 2, I present a novel method to simulate large numbers of species that each have their own unique niche.

    One matter of SDMs that is usually ignored but has been shown to be of great impact on model accuracy is the number of species occurrence records used to train a model. In chapter 2, I quantify the effect of sample size on model accuracy for species of different range size classes. The results show that the minimum number of records required to generate accurate SDMs is not uniform for species of every range size class and that larger sample sizes are required for more widespread species. By applying a uniform minimum number of records, SDMs of narrow-ranged species are incorrectly rejected and SDMs of widespread species are incorrectly accepted. Instead, I recommend to identify and apply the unique minimum numbers of required records for each individual species. The method presented here to identify the minimum number of records for species of particular range size classes is applicable to any species group and study area.

    The range size or prevalence is an important plant feature that is used in IUCN Red List classifications. It is commonly computed as the Extent Of Occurrence (EOO) and Area Of Occupancy (AOO). Currently, these metrics are computed using methods based on the spatial distribution of the known species occurrences. In chapter 3, using simulated species again, I show that methods based on the distribution of species occurrences in environmental parameter space clearly outperform those based on spatial data. In this chapter, I present a novel method that estimates the range size of a species as the fraction of raster cells within the minimum convex hull of the species occurrences, when all cells from the study area are plotted in environmental parameter space. This novel method outperforms all ten other assessed methods. Therefore, the current use of EOO and AOO based on spatial data alone for the purpose of IUCN Red List classification should be reconsidered. I recommend to use the novel method presented here to estimate the AOO and to estimate the EOO from the predicted distribution based on a thresholded SDM.

    In chapter 4, I apply the currently best possible methods to generate accurate SDMs and estimate the range size of species to the large dataset of Gabonese plant species records. All significant SDMs are used here to assess the unique contribution of narrow-ranged, widespread, and randomly selected species to patterns of species richness and weighted endemism. When range sizes of species are defined based on their full range in tropical Africa, random subsets of species best represent the pattern of species richness, followed by narrow-ranged species. Narrow-ranged species best represent the weighted endemism pattern. Moreover, the results show that the applied criterion of widespread and narrow-ranged is crucial. Too often, range sizes of species are computed on their distribution within a study area defined by political borders. I recommend to use the full range size of species instead. Secondly, the use of widespread species, of which often more data are available, as an indicator of diversity patterns should be reconsidered.

    The effect of global climate change on the distribution patterns of Gabonese plant species is assed in chapter 5 using SDMs projected to the year 2085 for two climate change scenarios assuming either full or no dispersal. In Gabon, predicted loss of plant species ranges from 5% assuming full dispersal to 10% assuming no dispersal. However, these numbers are likely to be substantially higher, as for many rare, narrow-ranged species no significant SDMs could be generated. Predicted species turnover is as high as 75% and species-rich areas are predicted to loose many species. The explanatory power of individual future climate anomalies to predicted future species richness patterns is quantified. Species loss is best explained by increased precipitation in the dry season. Species gain and species turnover are correlated with a shift from extreme to average values of annual temperature range.

    In the final chapter, the results are placed in a wider scientific context. First, the results on the methodological aspects of SDMs and their implications of the SDM pipeline are discussed. The method presented in this thesis to simulate large numbers of species offers opportunities to systematically investigate other matters of the pipeline, some of which are discussed here. Secondly, the factors that shape the current and predicted future patterns of plant species richness in Gabon are discussed including the location of centres of species richness and of weighted endemism in relation to the hypothesized location of glacial forest refugia. Factors that may contribute to the lower species richness of African rainforests compared with South American and Asian forests are discussed. I conclude by reflecting on the conservation of the Gabonese rainforest and its plant species as well as on the opportunities SDMs offer for this in the wider socio-economic context of a changing world with growing demand for food and other ecosystem services.

    Concealed diversity : taxonomical, phytogeographical and phytosociological notes on brambles (Rubus L. subgen. Rubus) in north-west Europe
    Haveman, Rense - \ 2017
    Wageningen University. Promotor(en): Joop Schaminee, co-promotor(en): Rienk Jan Bijlsma. - Wageningen : Wageningen University - ISBN 9789463431019 - 200
    rubus - diversity - taxonomy - phytogeography - geographical distribution - biogeography - apomixis - northwestern europe - rubus - diversiteit - taxonomie - plantengeografie - geografische verdeling - biogeografie - apomixis - noordwest-europa

    Rubus subgen. Rubus (bramble) is one of the large plant genera in Europe, consisting of only a few sexual biological species and at least 700 apomictic lineages. In this thesis, it is argued that the stabilised apomict lineages should best be regarded species, even if their distribution area doesn’t meet the requirements of a regional species as defined in several publications by Weber. Included is a checklist of Dutch bramble species, comprising 191 species belonging to Rubus subgen. Rubus. In the Netherlands, 97 of the 191 species are classified as regional species, with a distribution area diameter under 500 km. On the basis of distribution data of bramble species in Ireland, the UK, Denmark, Germany, and the Netherlands, 12 phytogeographical bramble-regions are distinguished. Although ecological factors play a role in the realisation of these regions, it is argued that the found patterns are primarily the result of evolutionary processes. The density and species composition of Rubus scrubs in the Netherlands is studied using landscape transects. At landscape scale, the bramble species in the scrubs are not randomly distributed, causing a spatial clustering of floristically similar bramble scrubs. It was concluded that only a part of the diversity of Rubus scrubs was accounted for in the Dutch national vegetation classification, and a new scrub type (the Rubetum taxandriae) was described on the basis of these findings. Rubus scrubs are an important biotope for rare shrub species and endemic Rubus species. Additionally, scrubs rich in bramble species are important because they provide foraging and nesting habitats for numerous vertebrates and invertebrates. It is recommended to include the apomict Rubus species in biodiversity accounts, for instance in the national standard list of plant species, as well as the Red List.

    The “Umbrella Effect” of the Natura 2000 network : an assessment of species inside and outside the European Natura 2000 protected area network : executive summary
    Jones-Walters, L.M. ; Gillings, Simon ; Groen, T.A. ; Hennekens, S.M. ; Noble, David ; Huskens, K. ; Santini, L. ; Sierdsema, H. ; Kleunen, A. van; Swaay, C. van; Sluis, T. van der - \ 2016
    Wageningen : Alterra, Wageningen-UR (Alterra-rapport 273A) - 11
    biodiversity - natura 2000 - birds directive - habitats directive - biogeography - biodiversiteit - natura 2000 - vogelrichtlijn - habitatrichtlijn - biogeografie
    BioScore 2 - Plants & Mammals : background and pre-processing of distribution data
    Hennekens, S.M. ; Hendriks, J.M. ; Ozinga, W.A. ; Schaminee, J.H.J. ; Santini, L. - \ 2015
    Wageningen : Statutory Research Tasks Unit for Nature & the Environment (WOt-technical report 50) - 221
    plants - mammals - biogeography - regression analysis - models - biodiversity - data collection - habitats - planten - zoogdieren - biogeografie - regressieanalyse - modellen - biodiversiteit - gegevens verzamelen - habitats
    This report highlights the background and pre-processing of the distribution of plant species, habitats and mammal species. For plants a selection of about 900 taxa has been made, based on 45 Annex I habitat types, which represent a substantial part of European natural and semi-natural vegetation. For animals all species existing in Europe have been taken into account. The data covers more or less all EU28 countries and is pre-processed in three steps to feed the BioScore 2 model. In the first step for each species or habitat type a climate/soil model has been created by using Boosted Regression Models (GBM). On the basis of these models presence/absence maps are derived to define the distribution range of the species/habitat types. In the second step additional knowledge was brought in to further specify the potential habitat within the distribution range, by laying an explicit mask over it, selecting only those land use types (land cover classes) suitable for the occurrence of the habitat type or species. In the third step the effect of human-induced pressures on habitat quality and species occurrence/abundance within the suitable habitats in the calculated distribution ranges was taken into account. The dose-effect relations were calculated on the basis of Generalized Linear Models (GLM). All outcomes of the three steps have been further used by the Netherlands Environmental Assessment Agency (PBL) to set up the BioScore 2 model.
    Rhyme and reason: plankton changes in the North Sea ecosystem
    Alvarez Fernandez, S. - \ 2015
    Wageningen University. Promotor(en): Han Lindeboom, co-promotor(en): Erik Meesters. - Wageningen : Wageningen University - ISBN 9789462573321 - 175
    plankton - aquatische ecologie - aquatische ecosystemen - zoöplankton - vissen - biogeografie - noordzee - plankton - aquatic ecology - aquatic ecosystems - zooplankton - fishes - biogeography - north sea


    The North Sea planktonic system is one of the most studied cases of sudden community changes in the marine environment. Continuous Plankton Recorder (CPR) data provided insight into the long-term trends and seasonal patterns of both phytoplankton and zooplankton and their relationships with hydrographical factors as well as climatological events during the last 50 years. A cold episodic event in the late 1970s and a shift towards a warmer community in the late 1980s have been thoroughly described in the literature. Both events have been related to different environmental factors, such as changes in sea surface temperature and Atlantic water inflow through the northern North Sea. This thesis was aimed to achieve a deeper understanding of long term plankton trends in the North Sea, detect more recent changes in the plankton community, and the environmental drivers behind them. The approach taken throughout this research consisted ofanalyzing extensive long term monitoring data in the open North Sea, the Dutch coastal area and the whole north-eastern North Atlantic.

    Here we described for the first time a change in the plankton community of the North Sea at the end of the 1990s. This change particularly affected the abundance and seasonal patterns of dinoflgellates and the dominant zooplankton group, the shelf-sea copepods (i.e. Temora longicornis, Pseudocalanus elongatus, Paracalanus sp.). Temperature changes and different water mass composition of the North Sea are suggested as main drivers behind this change.

    While looking more in detailed to the plankton trends in the Dutch North Sea waters, we identified an overall C:Chla increase. In coastal waters physiological adaptation to higher light and lower nutrient levels may have enhanced the C:Chlorophyll a, while different processes act in offshore waters. These findings not only indicate the rapidly changing environment in the Dutch coastal zone, but also about the validity of Chlorophyll a as an indicator of phytoplankton biomass trends.

    The detected changes in the planktonic system are not the only pelagic changes in the North Sea. We related the changes in plankton abundance and distribution with reported changes in recruitment of North Sea herring, particularly through the predator-prey relationship of some plankton species with pre-metamorphosis larvae. Even though spawning stock biomass has been high during the last decade, recruitment of North Sea herring has decreased since 2002. There were already indications that the early larval stage could be the critical point of development, with reduced survival and growth rates during the 2000s. The analyses presented here showed the abundance of Pseudocalanus sp. during winter to have a strong relationship with larval distribution and abundance later in herring life cycle, suggesting that predator-prey processes, and potentially starvation of first-feeding larvae, are behind the low recruitment in recent years.

    These changes in the North Sea pelagic ecosystem are not self-contained, but part of an even larger scale process taking place all across the northeastern Atlantic region. In thisthesis we showed how the changes detected in the North Sea, occurred synchronously in different Atlantic regions. This synchronicity suggests common global trends affecting marine ecosystems. We suggest that rising temperature and changes in oceanic circulation are behind this synchronicity, and that local circumstances, or atmospheric patterns with more local influences, such as North Atlantic Oscillation in the North Sea, modulate the responses of marine ecosystems. In the synthesis the main conclusions of each chapter are put in context together and the importance of zooplankton as a link between primary productivity and higher trophic level consumers is discussed. Furthermore, the importance of monitoring and the correct selection of biological and environmental indicators is also discussed.

    The knowledge provided by this doctoral thesis increase our understanding of the processes regulating the plankton community composition in the North Sea (Chapter 1 & 2) and the northeastern Atlantic region (Chapter 4), the potential relationship of plankton community with fish early-stage larvae (Chapter 3) and how environmental changes might affect the relevance of the indicators used to assess the state of the biological system (Chapter 2).

    Systematics, evolution and historical biogeography of the family Ochnaceae with emphasis on the genus Campylospermum
    Bissiengou, P. - \ 2014
    Wageningen University. Promotor(en): Marc Sosef, co-promotor(en): Lars Chatrou; L. Ngok Banak. - Wageningen : Wageningen University - ISBN 9789462572225 - 357
    ochnaceae - biosystematiek - taxonomie - evolutie - biogeografie - plantengeografie - fylogenie - taxonomische revisies - fylogenetica - ochnaceae - biosystematics - taxonomy - evolution - biogeography - phytogeography - phylogeny - taxonomic revisions - phylogenetics


    Ochnaceae s.l. is a family of trees, shrubs or rarely herbs widely distributed in tropical and subtropical forests and savannas of the Old and New World, and has about 500 species in 32 genera. The family is divided into three subfamilies: Medusagynoideae, Quiinoideae and Ochnoideae. We have provided, for the first time, a nearly complete molecular phylogenetic analysis of Ochnaceae s.l. resolving most of the phylogeny backbone of the family using five DNA regions. Based on this, dating analyses were performed using a secondary calibration, and relaxed molecular clock models. The historical biogeography of Ochnaceae s.l. was reconstructed using Dispersal-Vicariance Analysis and Bayesian Binary MCMC. The Neotropics were inferred as being the geographical origin of the family and the Old World was most likely colonized via the North Atlantic Land Bridge during a period when climatic conditions allowed establishment of a boreotropical flora. A full taxonomic revision of the continental African species of the genus Campylospermum has been prepared and additional historical biogeographic analyses were performed with a focus on the genus Campylospermum.

    Tracking butterflies for effective conservation
    Swaay, C.A.M. van - \ 2014
    Wageningen University. Promotor(en): Michiel Wallis de Vries; Marcel Dicke. - Wageningen : Wageningen University - ISBN 9789461739988 - 218
    lepidoptera - zoögeografie - biogeografie - populatiedynamica - natuurbescherming - monitoring - nederland - europa - lepidoptera - zoogeography - biogeography - population dynamics - nature conservation - monitoring - netherlands - europe
    Dit proefschrift bestaat uit drie delen: het volgen van veranderingen in de verspreiding van vlinders, het volgen van veranderingen in de populatiegrootte van vlinders en hoe deze kennis te gebruiken voor hun bescherming.
    Modelling concepts in biogeomorphology, results from presentations and discussions sessions of the workshop of 15 February
    Riksen, M.J.P.M. ; Groot, A.V. de; Keijsers, J.G.S. ; Poortinga, A. ; Voogt, I.H.A. - \ 2011
    Wageningen :
    geomorfologie - oeverecosystemen - biogeografie - geomorphology - riparian ecosystems - biogeography
    Interactions between vegetation and landscape evolution are a growing field of interest within earth sciences. With processes acting at different spatial and temporal scales, the system’s interactions are often complex. In order to simulate complex process interactions, choices on the approach of model development have to be made
    Biodiversity hotspots on the Dutch Continental Shelf: a marine strategy framework directive perspective
    Bos, O.G. ; Witbaard, R. ; Lavaleye, M.S.S. ; Moorsel, G.W.N.M. ; Teal, L.R. ; Hal, R. van; Hammen, T. van der; Hofstede, R. ter; Bemmelen, R.S.A. van; Witte, R.H. ; Geelhoed, S.C.V. ; Dijkman, E.M. - \ 2011
    IJmuiden : IMARES (Report / IMARES Wageningen UR C071/11) - 145
    biodiversiteit - inventarisaties - bescherming - cartografie - biogeografie - benthos - vis - vogels - zeezoogdieren - habitats - nederland - biodiversity - inventories - protection - mapping - biogeography - benthos - fish - birds - marine mammals - habitats - netherlands
    This report presenst hotspots of biodiversity for benthos, fish, birds, marine mammals and habitats on the Dutch Continental Shelf. These hotspots are based on a spatial application of biodiversity metrics developed in this study for the GES(Good Environmental Status)-descriptor 1 ‘Biological diversity is maintained’ of the Marine Strategy Framework Directive (MSFD) (EU 2008). The choice of the biodiversity metrics is based on the proposed indicators of biodiversity in the Commission Decision (EU 2010). The purpose of this study is to provide insight in possibilities for spatial protection measures in the framework of the MSFD. This report feeds information and ideas into further work for the MSFD in the Netherlands. IMARES has compiled this report for the Dutch Ministry of Economic Affairs, Agriculture and Innovation (Ministry of EL&I) and the Ministry of Infrastructure and the Environment (I&M).
    Geography of mammalian herbivores in the Indian Trans-Himalaya: patterns and processes
    Namgail, T. - \ 2009
    Wageningen University. Promotor(en): Herbert Prins, co-promotor(en): Sip van Wieren. - [S.l.] : S.n. - ISBN 9789085855248 - 122
    herbivoren - zoogdieren - zoögeografie - geografische verdeling - india - biogeografie - ecotonen - soortendiversiteit - soortenrijkdom - grote grazers - himalaya - herbivores - mammals - zoogeography - geographical distribution - india - biogeography - ecotones - species diversity - species richness - large herbivores - himalaya
    Animals need adequate resources so that their populations not only survive but thrive. So they seek places that can best provide them. Yet, they face several challenges, while obtaining these resources, e.g., predators, competitors and physical obstacles: mountains and rivers. Some animals are better-equipped to overcome these challenges, and are widely distributed, while others are not. These differences generate uneven pattern of distribution of life on earth. Tsewang Namgail’s study on the mammalian herbivores in the arid regions of the Himalayan mountains shows that interspecific competition is a major factor determining distribution and diversity patterns of these animals. Topography is also an important factor determining their coexistence, and thus it plays a crucial role in the formation and maintenance of herbivore assemblies in these drier, alpine regions. The study highlights that herbivores change their diet spectrum in response to the number of other herbivore species in an assemblage, and therefore emphasizes the inclusion of interspecific interactions in species distribution models.
    Ecopassage Griftenstein bij de N237 : advies voor het ontwerp van de faunapassage en toetsing effecten van vertsoring vanuit de omgeving
    Grift, E.A. van der - \ 2009
    Wageningen : Alterra (Alterra-rapport 1837) - 80
    natuurbeheer - wegen - infrastructuur - biogeografie - fauna - barrières - wildpassages - habitatfragmentatie - utrecht - habitatverbindingszones - nature management - roads - infrastructure - biogeography - fauna - barriers - wildlife passages - habitat fragmentation - utrecht - habitat corridors
    In opdracht van de Provincie Utrecht is een advies opgesteld voor het ontwerp van Ecopassage Griftenstein. Het advies omvat aanbevelingen betreffende het type faunapassage dat aan de eisen van alle doelsoorten voldoet, de dimensies en inrichting van de faunapassage, de dimensies en inrichting van de ecologische verbinding rondom de faunapassage, de positionering van de faunapassage, aanvullende maatregelen rondom de verkeersweg die het functioneren van de faunapassage vergroten en het al dan niet toestaan van recreatief medegebruik. Daarnaast is een toetsing van de effecten van verstoring vanuit de omgeving uitgevoerd. Hierbij zijn de mogelijke gevolgen voor het functioneren van de ecologische verbinding onderzocht van (1) de geplande woningbouw op het Hessingterrein direct ten oosten van de ecologische verbinding en (2) de geplande renovatie van de Werken van Griftenstein direct ten westen van de ecologische verbinding. Tevens zijn mitigerende maatregelen voor de effecten van verstoring verkend
    Revealing the secrets of African annonaceae : systematics, evolution and biogeography of the syncarpous genera Isolona and Monodora
    Couvreur, T.L.P. - \ 2008
    Wageningen University. Promotor(en): Marc Sosef, co-promotor(en): J.E. Richardson; Lars Chatrou. - [S.l.] : S.n. - ISBN 9789085049241 - 296
    annonaceae - isolona - monodora - evolutie - taxonomie - plantengeografie - biogeografie - klassen - moleculaire taxonomie - taxonomische revisies - soorten - determinatietabellen - identificatie - afrika - annonaceae - isolona - monodora - evolution - taxonomy - phytogeography - biogeography - genera - molecular taxonomy - taxonomic revisions - species - keys - identification - africa
    The goal of this PhD project was to study the evolution, systematics and biogeography of two African genera from the pan-tropical Annonaceae family: Isolona and Monodora. Both genera are unique within the family in that the female reproductive parts (or carpels) are fused into a single unit. All other Annonaceae have freely arranged carpels. We investigated the phylogenetic relationships of Isolona and Monodora at the intra-familial and intra-generic levels.
    In Chapter 2, we explore the influence of priors when using the novel Bayesian based posterior mapping to study the evolution of morphological characters. Up to now, it was unclear if these priors had any influence on the results. Using a family level molecular phylogeny of the Annonaceae, we study the evolution of two morphological characters under different prior values. We show that different prior values will return different results. Thus, inadequate prior values can lead to erroneous conclusions over the evolution of the studied morphological characters. We also indicate a practical way to choose the prior values when using the posterior mapping approach to study morphological character evolution.
    In Chapter 3, using the posterior mapping approach, we study the evolutionary origins of syncarpy in Annonaceae. The closest relatives of Isolona and Monodora are elucidated. We generate a well resolved phylogeny which included for the first time the majority of African Annonaceae genera. We also study additional morphological and palynological characters relevant to Annonaceae classification in general. Our phylogenetic analyses recover a fully resolved clade comprising twelve endemic African genera, including Isolona and Monodora, which was nested within the so-called long-branch clade. This is the largest and most species-rich clade of African genera identified to date within Annonaceae. Our results indicate that syncarpy arose by fusion of a moderate number of carpels. The alternative hypothesis that syncarpy arose by multiplication of an initial single carpel receives no support.
    In Chapter 4 we use African Annonaceae as a model family to study the biogeographical aspects of the evolutionary origins of African rain forests. It is generally thought that the large West-Central rain forest blocks was continuous during the Eocene with the now fragmented and smaller forests of East Africa, explaining the strong floristic affinities between both areas. Using dated molecular phylogenies we provide evidence of the recurring break-up and reconnection of this pan-African rain forest during the Oligocene and Miocene. The reconnections allowed for biotic exchange while the break-ups induced speciation enhancing the levels of endemicity, thus providing an explanation for present-day patterns in the distribution and diversity of plants in African rain forests.
    In Chapter 5, we perform a detailed analysis of pollen morphology within a strongly supported monophyletic group of five African genera, including Isolona and Monodora. We specifically assess if pollen characters are useful for classification purposes within Isolona and Monodora using a species-level molecular phylogeny. The results show a wide pollen morphological diversity. The pollen types defined within Isolona and Monodora provide little taxonomic information for major clades within both genera. However, pollen variation proves useful as a support of phylogenetic relatedness between groups of closely related species.
    Finally in Chapter 6, a monographic revision of both Isolona and Monodora is presented. Isolona consists of 20 species with five endemic to Madagascar and one newly described species. Monodora has a total of 14 species, three of which were described during this PhD project from Tanzania. Detailed descriptions as well as keys are provided. The conservation status of each species is assessed following the IUCN recommendations. Just under half of the total number of species from both genera is assigned to some level of threat (12 species or 60% in Isolona and four species or 28% in Monodora).
    Het snuitkevergenus Larinus in Nederland, met Larinus turbinatus als nieuwe soort voor de fauna (Coleoptera: Curculionidae).
    Heijerman, Th. - \ 2007
    Nederlandse Faunistische Mededelingen 26 (2007). - ISSN 0169-2453 - p. 1 - 16.
    larinus - biologische bestrijding - biosystematiek - curculionidae - coleoptera - zoögeografische gebieden - biogeografie - verspreiding - dierecologie - larinus - biological control - biosystematics - curculionidae - coleoptera - zoogeographical regions - biogeography - dispersal - animal ecology
    Met enige regelmaat worden nieuwe kevers voor de Nederlandse fauna gerapporteerd. In deze bijdrage wordt Larinus turbinatus voor het eerst gemeld. Deze soort werd in 2004 voor het eerst in ons land aangetroffen en is sindsdien op diverse locaties waargenomen en verzameld. Het is verleidelijk om de komst van weer een nieuwe soort te verklaren op grond van het veranderende klimaat. Maar gezien de Europese verspreiding lijkt het in dit geval geen aannemelijke verklaring
    Coleoptera-Kevers. Entomofauna van Noord-Drenthe. Verslag van de 160e zomerbijeenkomst te Schipborg
    Cuppen, J.G.M. ; Vorst, O. ; Heijerman, Th. ; Drost, M.P.B. ; Nunen, B.M.P.J. van; Jansen, R.P. ; Ee, G. ; Maanen, B. van; Muilwijk, M. ; Huijbregts, J. ; Langeveld, S.C. ; Threels, A. - \ 2006
    Entomologische Berichten 60 (2006)3. - ISSN 0013-8827 - p. 80 - 88.
    entomologie - populatie-ecologie - fauna - biogeografie - entomology - population ecology - fauna - biogeography
    Tijdens de 160e zomerbijeenkomst van de Nederlandse Entomologische Vereniging zijn 1425 soorten van tien insectenordes waargenomen. 81 soorten werden voor het eerste gemeld voor de provincie Drenthe en drie soorten zijn zelfs helemaal nieuw voor de Nederlandse fauna. Een verslag van de bijeenkomst
    Hofstede, R. ter - \ 2006
    IJmuiden : IMARES (Rapport / IMARES C056/06) - 16
    kustwateren - karteren - imi verspreidingskaarten - biogeografie - periode van kuitschieten - haringen - kabeljauw - schelvis - wijting - makrelen - schol - tong (vis) - coastal water - surveying - imi distribution maps - biogeography - spawning season - herrings - cod - haddock - whiting - mackerels - plaice - dover soles
    Rijkswaterstaat (RWS) dient als beheerder van de Noordzee en de kustwateren deskundig en adequaat te opereren bij milieucalamiteiten en rampen. Daarvoor is kennis nodig betreffende het ecologisch en economisch functioneren van de Nederlandse mariene wateren. IMARES draagt hieraan bij door te voorzien in verspreidingskaarten van de paaigebieden van enkele mariene vissoorten op het Nederlands Continentaal Plat. Het betreft de commercieel belangrijke soorten haring, kabeljauw, schelvis, wijting, makreel, schol en tong. Deze kaarten zijn gebaseerd op internationale ei-surveys, waarbij de aantallen gevangen eieren per vangstpositie geschat worden. Paaigebieden en paaiperioden zijn in hoge mate variabel, daarom worden (met uitzondering van de kaart voor haring) geen begrenzingen aangegeven in de verspreidingskaarten.
    Burkholderia community structure in soils under different agricultural management
    Salles, J.F. - \ 2005
    Leiden University. Promotor(en): J.A. van Veen; J.D. van Elsas, co-promotor(en): J. Balandreau; E. van der Meijden; E.J.J. Lugtenberg. - Wageningen : Ponsen & Looijen BV - ISBN 9789064648861 - 143
    burkholderia - bacteriën - bodembacteriën - bodembiologie - biogeografie - bedrijfsvoering - landbouw - organismen ingezet bij biologische bestrijding - burkholderia - bacteria - soil bacteria - soil biology - biogeography - management - agriculture - biological control agents
    Kwaliteit van groenblauwe dooradering en voorkomen van vogels, vlinders en planten
    Geertsema, W. ; Grashof, C.J. ; Meeuwsen, H.A.M. ; Schotman, A.G.M. ; Turnhout, C. van; Swaay, C. van - \ 2004
    Wageningen : Alterra (Alterra-rapport 1095) - 99
    vogels - lepidoptera - planten - biogeografie - landschap - ruimtelijke variatie - soortendiversiteit - ecologie - nederland - ecologische hoofdstructuur - birds - lepidoptera - plants - biogeography - landscape - spatial variation - species diversity - ecology - netherlands - ecological network
    In dit rapport wordt de relatie tussen kenmerken van groenblauwe dooradering en soortenrijkdom van een aantal soortgroepen in agrarische gebieden in Nederland gekwantificeerd. Daarbij ligt de nadruk op de ruimtelijke rangschikking van de landschapselementen. De relaties worden beschreven met behulp van statistische modellen waarmee de kans op aanwezigheid van planten, vlinders en vogels wordt berekend. Het bleek dat de ruimtelijke rangschikking van de landschapselementen de soortenrijkdom van alle drie de soortgroepen beïnvloedt. De resultaten kunnen worden gebruikt bij het evalueren of plannen van maatregelen die moeten leiden tot grotere natuurwaarden in groenblauwe dooradering
    Topografische inventarisatieatlas flora en fauna van Nederland
    Have, T.M. van der; Huigen, P. - \ 2003
    Zeist : Vogelbescherming Nederland - ISBN 9789071473050 - 185
    kaarten - geografie - nederland - flora - fauna - biogeografie - habitats - inventarisaties - veldwerk - floristische gebieden - maps - geography - netherlands - flora - fauna - biogeography - habitats - inventories - field work - floristic regions
    Inventarisatie Vogelbescherming Nederland
    De natuurkalender : is vervroeging van het voorjaar zichtbaar? [themanummer klimaatsverandering]
    Vliet, A.J.H. van; Groot, R.S. de - \ 2003
    De Levende Natuur 104 (2003)3. - ISSN 0024-1520 - p. 99 - 100.
    habitats - biogeografie - fenologie - klimaatverandering - natuurbescherming - databanken - monitoring - nederland - biogeography - phenology - climatic change - nature conservation - databases - netherlands
    In de levensloop van planten en dieren speelt "timing" van jaarlijks terugkerende verschijnselen in de natuur een zeer belangrijke rol. Vele organisaties ondersteunen het waarnemingsprogramma
    Hylis foveicollis (Coleoptera: Eucnemidae), een dood-houtkever nieuw voor de Nederlandse fauna
    Moraal, L.G. ; Burgers, J. ; Vorst, O. - \ 2003
    Entomologische Berichten 63 (2003)2. - ISSN 0013-8827 - p. 36 - 39.
    coleoptera - biogeografie - zoögeografie - dood hout - nederland - coleoptera - biogeography - zoogeography - dead wood - netherlands
    Hylis foveicollis is recorded for the first time from The Netherlands. This beetle is very rare throughout Europe, but it can lokally be found in large numbers under favourable conditions. The larvae develop in soft dead wood and probably feed on fungi
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