6708 PB Wageningen
Jasper Wubs obtained his MSc (2010) from Utrecht University and PhD (2017) degree at Wageningen University (the Netherlands), where he studied plant-soil biota interactions and how they steer natural plant community dynamics and their use in nature restoration (with Prof. Martijn Bezemer and Prof. Wim van der Putten). Next, he obtained an NWO Rubicon (2018) grant to study how soil microbiomes can be used to improve soil restoration in degraded arable soils in the central Kenyan highlands (with Prof. Johan Six and Dr. Martin Hartmann at ETH Zurich).
In 2021 Jasper returned to the Netherlands to coordinate data collection and analysis within the new IJkcentrum voor de Bodem (https://nioo.knaw.nl/nl/ijkcentrumbodem) as part of the Onder het Maaiveld project (with IUCN, Vlinderstichting, WUR, Centre for Soil Ecology). The project aims to map and benchmark the soil biodiversity of the Netherlands to provide action perspectives for land managers.
Recently, Jasper received a EU MSCA Postdoctoral Fellowship to study soil multifunctionality in relation to the stoichiometry of plants, microbes and soils (MultiSol) and launched his own Research Group on Soils as Complex Adaptive Systems.
Global warming and precipitation extremes (drought or increased precipitation) strongly affect plant primary production and thereby terrestrial ecosystem functioning. Recent syntheses show that combined effects of warming and precipitation extremes on plant biomass are generally additive, while individual experiments often show interactive effects, indicating that combined effects are more negative or positive than expected based on the effects of single factors. Here, we examined whether variation in biomass responses to single and combined effects of warming and precipitation extremes can be explained by plant growth form and community type. We performed a meta-analysis of 37 studies, which experimentally crossed warming and precipitation treatments, to test whether biomass responses to combined effects of warming and precipitation extremes depended on plant woodiness and community type (monocultures versus mixtures). Our results confirmed that the effects of warming and precipitation extremes were overall additive. However, combined effects of warming and drought on above- and belowground biomass were less negative in woody- than in herbaceous plant systems and more negative in plant mixtures than in monocultures. We further show that drought effects on plant biomass were more negative in greenhouse- than in field studies, suggesting that greenhouse experiments may overstate drought effects in the field. Our results highlight the importance of plant system characteristics to better understand plant responses to climate change.
Interactions between aboveground and belowground organisms are important drivers of plant growth and performance in natural ecosystems. Making practical use of such above-belowground biotic interactions offers important opportunities for enhancing the sustainability of agriculture, as it could favor crop growth, nutrient supply, and defense against biotic and abiotic stresses. However, the operation of above-and belowground organisms at different spatial and temporal scales provides important challenges for application in agriculture. Aboveground organisms, such as herbivores and pollinators, operate at spatial scales that exceed individual fields and are highly variable in abundance within growing seasons. In contrast, pathogenic, symbiotic, and decomposer soil biota operate at more localized spatial scales from individual plants to patches of square meters, however, they generate legacy effects on plant performance that may last from single to multiple years. The challenge is to promote pollinators and suppress pests at the landscape and field scale, while creating positive legacy effects of local plant-soil interactions for next generations of plants. Here, we explore the possibilities to improve utilization of above-belowground interactions in agro-ecosystems by considering spatio-temporal scales at which aboveground and belowground organisms operate. We identified that successful integration of above-belowground biotic interactions initially requires developing crop rotations and intercropping systems that create positive local soil legacy effects for neighboring as well subsequent crops. These configurations may then be used as building blocks to design landscapes that accommodate beneficial aboveground communities with respect to their required resources. For successful adoption of above-belowground interactions in agriculture there is a need for context-specific solutions, as well as sound socio-economic embedding.
In this project (with NIOO, ETH Zurich, CIRAD, PE&RC, University of Eldoret), we developped a new transdisciplinary field course on agro-ecology in the Elegyo-Marakwet area, Kenya: "African roads to Sustainable Agroecology". A new edition of the course is anticipated in 2024.
Many soils in sub-Saharan Africa (SSA) have been chemically, physically and biologically degraded. As a result an estimated 50% of agricultural soils do not increase productivity in response to mineral fertiliser addition, so called non-responsive soils. These soils can be restored using Integrated Soil Fertility Management (ISFM), but this requires substantial amounts of organic substrates (e.g. manure) to be added to the soil for many years. Many farmers in SSA do not possess these kinds of resources. Plants, including crops, grow in tight associations with their specific soil microbiomes – the collective diversity of bacteria, archaea, fungi, protists, and other microorganisms found in soil. The soil microbiome can enhance plant functioning, particularly when introduced as consortia of species.
In this project we combine modern high-throughput DNA sequencing methods and controlled greenhouse cultivations to explore the relationship between Kenyan maize crops and the natural diversity of soil microbiomes. We assess microbiome diversity in central Kenya, screen the potential of naturally occurring soil microbiomes to improve the performance of maize crops, and use host-mediated selection to engineer microbiomes competent to function under reduced organic substrate inputs.
NWO, Biodiversiteit werkt, with Prof. T.M. Bezemer and Prof. W.H. van der Putten.
Jasper actively takes his research out of academia and to practitioners, policy makers and the general public. For this work he received the 2016 Parnassia Award from the Radboud University Nijmegen.