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You searched for +publisher:"Wageningen University" +contributor:("D. Kleijn"). Showing records 1 – 3 of 3 total matches.

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1. Fijen, Thijs P.M. Towards ecological intensification : the relative importance of wild pollinators as an agricultural input in seed production.

Degree: 2019, Wageningen University

The importance of wild pollinators compared to conventional agricultural management is undervalued, suggests the PhD thesis of Thijs Fijen of Wageningen University. A study in commercial leek seed production fields shows that wild pollinators contribute as much to crop yield as plant quality. Honeybees, placed next to flowering leek fields specifically for pollination, do not contribute much to crop yield. Experimental work confirmed these findings: a 50% reduction in pollination leads to much larger reductions in seed yield than similar reductions in fertilizer applications or irrigation. Surprisingly, a 50% reduction in fertilisation resulted in equally high, or higher crop yields. These results may explain the international trend that crop yields of insect-pollinated crops increase less fast as those of wind-pollinated crops. The research of Fijen furthermore shows that both crop pollination and pollinator biodiversity in agricultural landscapes can be promoted by better protection of semi-natural habitats such as flower-rich road sides and nature areas. Advisors/Committee Members: Wageningen University, D. Kleijn, J. van Ruijven, J.A. Scheper.

Subjects/Keywords: Natuurbeheer en Plantenecologie; Plantenecologie en Natuurbeheer; PE&RC; Nature Conservation and Plant Ecology; Plant Ecology and Nature Conservation; PE&RC

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Fijen, T. P. M. (2019). Towards ecological intensification : the relative importance of wild pollinators as an agricultural input in seed production. (Doctoral Dissertation). Wageningen University. Retrieved from http://library.wur.nl/WebQuery/wurpubs/553110 ; urn:nbn:nl:ui:32-553110 ; urn:nbn:nl:ui:32-553110 ; http://library.wur.nl/WebQuery/wurpubs/553110

Chicago Manual of Style (16th Edition):

Fijen, Thijs P M. “Towards ecological intensification : the relative importance of wild pollinators as an agricultural input in seed production.” 2019. Doctoral Dissertation, Wageningen University. Accessed February 23, 2020. http://library.wur.nl/WebQuery/wurpubs/553110 ; urn:nbn:nl:ui:32-553110 ; urn:nbn:nl:ui:32-553110 ; http://library.wur.nl/WebQuery/wurpubs/553110.

MLA Handbook (7th Edition):

Fijen, Thijs P M. “Towards ecological intensification : the relative importance of wild pollinators as an agricultural input in seed production.” 2019. Web. 23 Feb 2020.

Vancouver:

Fijen TPM. Towards ecological intensification : the relative importance of wild pollinators as an agricultural input in seed production. [Internet] [Doctoral dissertation]. Wageningen University; 2019. [cited 2020 Feb 23]. Available from: http://library.wur.nl/WebQuery/wurpubs/553110 ; urn:nbn:nl:ui:32-553110 ; urn:nbn:nl:ui:32-553110 ; http://library.wur.nl/WebQuery/wurpubs/553110.

Council of Science Editors:

Fijen TPM. Towards ecological intensification : the relative importance of wild pollinators as an agricultural input in seed production. [Doctoral Dissertation]. Wageningen University; 2019. Available from: http://library.wur.nl/WebQuery/wurpubs/553110 ; urn:nbn:nl:ui:32-553110 ; urn:nbn:nl:ui:32-553110 ; http://library.wur.nl/WebQuery/wurpubs/553110

2. Gils, van, Stijn Herman. It depends: : effects of soil organic matter in aboveground-belowground interactions in agro-ecosystems.

Degree: 2017, Wageningen University

Over the last decades agricultural production increased drastically due to the use of external inputs. However, the use of external inputs has high environmental costs and may negatively influence ecosystem processes such as pollination and pest control that underpin agricultural production. Soil organic matter has been proposed as a potential alternative to external inputs as it relates to multiple yield promoting ecosystem processes. The aim of my thesis is to assess whether and how soil organic matter content alters the effect of some ecosystem processes and external inputs on crop yield. I examined whether soil organic matter alters biomass of wheat and oilseed rape under fertilizer supply. Other biotic and abiotic factors that operate at different spatial and temporal scales are also included in some of these experiments. I found that under controlled conditions soil organic matter may reduce the positive effect of mineral fertilizer supply on crop biomass. The reduction changed with the presence or absence of a pathogenic root fungus, but not with drought stress. Moreover, soil organic matter enhances performance of aphids under controlled greenhouse conditions, but the enhancement was less than fertilizer supply. None of these controlled experiments, however, showed that soil organic matter can be an alternative to mineral fertilizer supply. Under field conditions soil organic matter did not strongly affect plant nutrient availability or performances of aphid and its natural enemies. The relation between soil organic matter and plant biomass in a greenhouse experiment did not change with organic management or the duration of it, neither did it change with pollinator visitation rate, an ecosystem process that is managed on the landscape scale. These results suggest that soil organic matter may relate to ecosystem services that influence crop yield, whereas these relations might not be significant under field conditions. Collectively, all these results suggest that the relation between soil organic matter content and ecosystem processes that benefit crop yield is highly context dependent. I propose future research may focus on (1) the quality of soil organic matter rather than the content per se and (2) the relation between soil organic matter content and crop yield under realistic conditions in a longer term. Advisors/Committee Members: Wageningen University, W.H. van der Putten, D. Kleijn.

Subjects/Keywords: organisch bodemmateriaal; agro-ecosystemen; aphidoidea; kunstmeststoffen; tarwe; koolzaad; gewasopbrengst; ecosysteemdiensten; voedingsstoffenbeschikbaarheid; plagenbestrijding; biologische landbouw; Bodemvruchtbaarheid; soil organic matter; agroecosystems; aphidoidea; fertilizers; wheat; rape; crop yield; ecosystem services; nutrient availability; pest control; organic farming; Soil Fertility

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Gils, van, S. H. (2017). It depends: : effects of soil organic matter in aboveground-belowground interactions in agro-ecosystems. (Doctoral Dissertation). Wageningen University. Retrieved from http://library.wur.nl/WebQuery/wurpubs/526080 ; urn:nbn:nl:ui:32-526080 ; urn:nbn:nl:ui:32-526080 ; http://library.wur.nl/WebQuery/wurpubs/526080

Chicago Manual of Style (16th Edition):

Gils, van, Stijn Herman. “It depends: : effects of soil organic matter in aboveground-belowground interactions in agro-ecosystems.” 2017. Doctoral Dissertation, Wageningen University. Accessed February 23, 2020. http://library.wur.nl/WebQuery/wurpubs/526080 ; urn:nbn:nl:ui:32-526080 ; urn:nbn:nl:ui:32-526080 ; http://library.wur.nl/WebQuery/wurpubs/526080.

MLA Handbook (7th Edition):

Gils, van, Stijn Herman. “It depends: : effects of soil organic matter in aboveground-belowground interactions in agro-ecosystems.” 2017. Web. 23 Feb 2020.

Vancouver:

Gils, van SH. It depends: : effects of soil organic matter in aboveground-belowground interactions in agro-ecosystems. [Internet] [Doctoral dissertation]. Wageningen University; 2017. [cited 2020 Feb 23]. Available from: http://library.wur.nl/WebQuery/wurpubs/526080 ; urn:nbn:nl:ui:32-526080 ; urn:nbn:nl:ui:32-526080 ; http://library.wur.nl/WebQuery/wurpubs/526080.

Council of Science Editors:

Gils, van SH. It depends: : effects of soil organic matter in aboveground-belowground interactions in agro-ecosystems. [Doctoral Dissertation]. Wageningen University; 2017. Available from: http://library.wur.nl/WebQuery/wurpubs/526080 ; urn:nbn:nl:ui:32-526080 ; urn:nbn:nl:ui:32-526080 ; http://library.wur.nl/WebQuery/wurpubs/526080

3. Oram, Natalie J. Root interactions in a diverse grassland : the role of root traits in belowground productivity and decomposition.

Degree: 2018, Wageningen University

Background Plant diversity influences ecosystem functioning. A positive relation between plant diversity and productivity above- and belowground has been established. Aboveground, this effect has been shown to be due to complementarity effects, interactions between species in a mixture that lead species to, on average, produce more biomass than expected based on their productivity in monoculture. The mechanisms underlying complementarity effects and the positive diversity-productivity relation are predicted to lie belowground, e.g. resource partitioning and/or facilitation. The relation between plant diversity and decomposition is less clear, and research on the diversity-decomposition relation belowground is limited. This is an important gap in biodiversity knowledge, as the decomposition of plant litter is the major source of nutrients and carbon in terrestrial ecosystems, and most plant litter in grasslands is belowground. Methods This thesis explored the effect of plant diversity on belowground productivity and decomposition. Belowground complementarity effects were quantified in the Jena Trait Based Experiment, and the diversity of or plasticity in species-specific vertical root distribution as underlying mechanism was tested. The plant diversity- root decomposition relation was quantified in the Jena Experiment and the Jena Trait Based Experiment. The role of root traits and the soil environment as mediating factors were tested. Major findings Plant diversity had a positive effect on root biomass production, and this relation was attributed to complementarity effects. The diversity in species-specific vertical root distribution did not explain complementarity effects, and thus, is not likely a major mechanism underlying the diversity-productivity relation. Species altered their vertical root distribution in response to inter-specific neighbours. The direction of this change differed between functional groups: grasses became shallower in mixture, forbs became deeper. This change did not explain species-specific belowground relative productivity (relative to monoculture productivity). Therefore, plasticity in vertical root distribution was not a major factor underlying belowground complementarity effects or the diversity-productivity relation. Functional group composition, not plant diversity, had a consistent effect on root decomposition. The presence or abundance of grasses consistently reduced root litter quality and decomposition. In the Jena Experiment, plant diversity had a negative effect on root decomposition, mainly due to shifts in functional group composition over a diversity gradient. In the Jena Trait Based Experiment, root decomposition was unaffected by plant diversity, but decreased as the abundance of grass roots increased. Root traits were found to be important in explaining variation in root decomposition. Conclusions Plant diversity had a positive effect on belowground productivity, which could be attributed to complementarity… Advisors/Committee Members: Wageningen University, D. Kleijn, J. van Ruijven.

Subjects/Keywords: Bodembiologie en biologische bodemkwaliteit; Leerstoelgroep Bodembiologie en biologische Bodemkwaliteit; Bodembiologie; Natuurbeheer en Plantenecologie; Plantenecologie en Natuurbeheer; PE&RC; Chair Soil Biology and Biological Soil Quality; Soil Biology and Biological Soil Quality; Soil Biology; Nature Conservation and Plant Ecology; Plant Ecology and Nature Conservation; PE&RC

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Oram, N. J. (2018). Root interactions in a diverse grassland : the role of root traits in belowground productivity and decomposition. (Doctoral Dissertation). Wageningen University. Retrieved from http://library.wur.nl/WebQuery/wurpubs/535468 ; urn:nbn:nl:ui:32-535468 ; urn:nbn:nl:ui:32-535468 ; http://library.wur.nl/WebQuery/wurpubs/535468

Chicago Manual of Style (16th Edition):

Oram, Natalie J. “Root interactions in a diverse grassland : the role of root traits in belowground productivity and decomposition.” 2018. Doctoral Dissertation, Wageningen University. Accessed February 23, 2020. http://library.wur.nl/WebQuery/wurpubs/535468 ; urn:nbn:nl:ui:32-535468 ; urn:nbn:nl:ui:32-535468 ; http://library.wur.nl/WebQuery/wurpubs/535468.

MLA Handbook (7th Edition):

Oram, Natalie J. “Root interactions in a diverse grassland : the role of root traits in belowground productivity and decomposition.” 2018. Web. 23 Feb 2020.

Vancouver:

Oram NJ. Root interactions in a diverse grassland : the role of root traits in belowground productivity and decomposition. [Internet] [Doctoral dissertation]. Wageningen University; 2018. [cited 2020 Feb 23]. Available from: http://library.wur.nl/WebQuery/wurpubs/535468 ; urn:nbn:nl:ui:32-535468 ; urn:nbn:nl:ui:32-535468 ; http://library.wur.nl/WebQuery/wurpubs/535468.

Council of Science Editors:

Oram NJ. Root interactions in a diverse grassland : the role of root traits in belowground productivity and decomposition. [Doctoral Dissertation]. Wageningen University; 2018. Available from: http://library.wur.nl/WebQuery/wurpubs/535468 ; urn:nbn:nl:ui:32-535468 ; urn:nbn:nl:ui:32-535468 ; http://library.wur.nl/WebQuery/wurpubs/535468

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