Soil is a home for an unbelievable diversity and abundance of microbial life that is essential for supporting life on our planet.

How soil microbial composition impacts structure and composition of the aboveground plant and animal communities?

The main research question of this thesis was: Can nitrogen cycling on dairy farms on peat soil in the Dutch Green Heart area be improved by adapting management to the nitrogen supply from soil and by using other grassland species and crops without affecting milk production?

Promotor: J.A. van Veen, Co-promotor: E.E. Kuramae

In this thesis, the role of plant-mediated soil legacy effects in shaping aboveground plant-insect interactions was investigated.

Promotores: Prof.dr. H. van Veen & Prof.dr. W. de Boer (Wageningen University)

Soil biodiversity is of great importance for the maintenance of multifunctionality in terrestrial ecosystems.

Promotores: J.A.van Veen, P.L.G.Klinkhamer. Co-promotor: E.E.Kuramae

The soil ecosystem consists of the largest reservoir of biodiversity on Earth.

By growing in a soil plants change the biotic and abiotic properties of the soil in which they grow.

How presence, abundance and enzymatic activities of AM and EM fungi differently affect soil carbon sequestration processes?

Plants and soils from natural ecosystems harbor great diversity of soil microorganisms, which could potentially contribute to the sustainability of horticulture. The knowledge about using wild plant species and soil from natural ecosystem to improve the crop health will advance the application of ecological…

In this thesis, I focused on studying the above- and belowground interactions of J. vulgaris from a plant-soil feedback (hereafter, PSF) perspective. I investigated the temporal variation of negative PSF and examined the effects of root-associated bacteria on plant performance and aboveground herbiv…

The use of N fertilizers has increased worldwide in the past century. While this increased input of N has increased food productivity, it has also contributed to decreases in biodiversity, soil quality and environmental health, including increases in greenhouse gas emissions.

Vinasse is a major by-product generated by the sugarcane biofuel industry. It is a source of microbes, nutrients and organic matter and often it is recycled as fertilizer.

In this PhD study, I aim to deepen our understanding of the influence of major mycorrhizal types, namely arbuscular mycorrhizae (AM) and ectomycorrhizae (EM), on the global soil carbon cycle and their potential distribution changes under future environmental shifts.

Striga hermonthica, commonly known as witchweed, infests major cereal crops in Sub-Saharan Africa causing severe yield losses and threatening the livelihood of millions of resource poor farmers.

Promotors: Prof.dr. G.R. de Snoo, Prof.dr. G.A. Persoon, Prof.dr.ir. H.H. de Iongh

De

‘Wat ik aantrekkelijk vind aan het bodemleven, is dat het stuurbaar is,’ verklapt onderzoeker Martijn Bezemer van het Instituut Biologie Leiden (IBL). ‘Dat je kan zeggen: wat wil je? En dat ik de bodem dan kan omtoveren tot iets wat jij nodig hebt. Ten minste, dat dachten we.’

What are the global relationships between environmental conditions and abundance of distinct types of mycorrhizal fungi in soil and plant roots?

Jan Willem Erisman wilde als kind al dingen beter maken. Als hoogleraar Duurzaamheid en Milieu is hij daarom ook buiten de universiteit actief. Hij staat bekend als de stikstofprofessor: in de media, maar ookin de Tweede Kamer legt hij het stikstofprobleem uit. Recent trad hij toe tot de Europese Soil…

Promotor: Prof.dr. W.J.G.M. Peijnenburg

The rapidly increasing commercial application of metallic nanoparticles within products will inevitably enhance the amount of NPs being released into soil.

1. To what extent do metallic NPs added to soil extractions change the activity, abundance, or community composition of microbes? 2. How do the effects of metallic NPs on soil microbes differ from the effects of the ions shedding from corresponding NPs?

How the global distribution of vegetation stands dominated by arbuscular and ectomycorrhizal plants relate to principle aspects of belowground carbon accumulation processes?

Microbiome composition of the spermosphere and the rhizosphere of wild and modern bean accessions grown in an agricultural and a native soil from Colombia was characterized by metagenomics and cultivation-dependent approaches.

Streptomyces are bacteria abundant in soil that participate in diverse and complex interactions. These bacteria are the main producers of the antibiotics we currently use in the clinic.

Promotor: E.F. Smets Co-promotor: J. Geml

Promotor: E.F. Smets, Co-promotor: J. Geml

The soil-dwelling, filamentous bacteria of the genus Streptomyces are renowned for their production of useful secondary metabolites including antibiotics. The work described in this thesis provides new insights on the role and regulation of antibiotic production and resistance in these bacteria.

This thesis aimed to investigate the impact of exposure dynamics, relative contributions of ENPs(particle) and ENPs(ion), and dosing regimens on the toxicity of ENPs varying in different physico-chemical properties, on the composition and functioning of soil microbial communities.

Promotie

Promotores: Prof.dr.G.R. de Snoo and Dr. R. Heijungs

The filamentous bacteria Streptomyces are widespread inhabitants of terrestrial soils.

Promotie

Promotie

Een leefbare aarde. Meer biodiversiteit. En verstandig omgaan met resources. Bij het CML willen we impact maken met ons onderzoek én onderwijs. Op deze website lees je hoe we dat doen.

Promotor: Prof.dr. G.P. van Wezel

Muziek van een composteerbare cello, foto’s en geurtjes van schimmels en een geweven wandkleed. Het zijn een aantal voorbeelden uit Super Organism, het kunstproject van Suzette Bousema waarin je de ondergrondse schimmelwereld met al je zintuigen kunt beleven. Leids milieuwetenschapper Nadia Soudzolovskaia…

Herstel van de natuur op uitgeputte landbouwgrond en in natuurgebieden verloopt moeizaam. ‘Bodemtransplantatie’ kan mogelijk uitkomst bieden. Dat betoogt Martijn Bezemer, hoogleraar Ecologie van Plant-Microbe-Insect interacties. Oratie op 18 december.

How can we quantify the density of species within a community through environmental DNA concentrations?

Supervisor: P.J.J. Hooykaas

Food security is challenged by a growing global population and by climate change. Drought and soil salinity are considered the most important ones that inhibit crop yield and distribution. Worryingly, climate change is predicted to increase not only their frequency and severity, but also their co-occurrence,…

Mycorrhizas are symbiotic associations between soil fungi and most plant species.

Promotor: G.P. van Wezel, Co-promotor: D. Claessen

The thesis describes terrestrial field trials aimed to detect side-effects of pesticides within the framework of pesticide registration procedures. Field trials were developed using vascular plants Brassica napus and Poa annua, caterpillars Pieris brassicae and effects on decomposition were studied…