Research Hans De Boeck

Abstract

Amplified arctic warming lessens the temperature difference between the Arctic and the tropics, resulting in more sluggish circulation patterns and a "wavier" jet stream. Consequently, the mid-latitude regions (30-60°N) are expected to experience more persistent weather patterns characterized by prolonged dry and wet spells. Longer droughts are likely to increase extreme water shortages that undermine food security, and extreme rainfall can cause soil erosion and reduce crop productivity by gradually leaching the fertile topsoil. Agricultural grasslands are particularly sensitive to changes in the seasonality, frequency, and intensity of stress events as predicted by climate models8, with potential impact on carbon sinks and fodder provisioning for livestock. In this project we will study different grass cultivars' performance under more persistent precipitation and the potential benefits of mixing these cultivars. In addition, we will elucidate the role of mycorrhiza in potentially strengthening ecosystem resilience by assessing their modulating effects on grass growth, water potential and regulation of grass secondary metabolism, antioxidant enzymatic system, hormones, and gene expression under regimes of alternating prolonged dry and wet spells.

Researcher(s)

• Promoter: Nijs Ivan
• Co-promoter: Beemster Gerrit
• Co-promoter: De Boeck Hans
• Co-promoter: Struyf Eric
• Co-promoter: Verbruggen Erik

Research team(s)

• Plant and Ecosystems (PLECO) - Ecology in a time of change

Project type(s)

• Research Project

Abstract

Developing a resilient and sustainable agriculture system, and the agroecological transitions requires a deep understanding of agroecosystems, their interactions with the environment, and management practices. AgroServ features a large consortium of research infrastructures, most of them being on the EU roadmap, and a vast offer of services at all scales, from the molecule to the organism, to the ecosystem, to the society. AgroServ will facilitate a systemic and holistic approach to understand the threats and challenges agriculture is facing, towards the implementation of a resilient and sustainable agri-food system. We propose a transdisciplinary offer of services, integrating the actors of the agriculture system in the research process, of which the farmers are the first, thanks to a wide offer of living labs across Europe. Most of the relevant field of sciences are represented in AgroServ, from natural to social sciences. We will develop a wider catalogue of integrated and customized services, thanks to a specific approach of service pipelines designed from a gap analysis, stakeholder and user demands. A strong community building and training program for access managers and users will be implemented to facilitate multi- and transdisciplinary research with all relevant actors. Results from the research performed under AgroServ will be synthetized to be used in the scope of evidence-based policy making. Data from AgroServ will be open and compliant with FAIR practices, and made available on the long-term to the communities, and be linked with the main European initiatives, as the EOSC. Strong links will be established with existing or future programs under H2020 and Horizon Europe, such as the partnerships agroecology, living labs and research infrastructures, and agriculture of data, as well as the two CSA AE4EU and ALL-READY, and the missions soil and plant health, and waters. AgroServ will collaborate with other relevant initiative in the Pillar II to of HE.

Researcher(s)

• Promoter: Nijs Ivan
• Co-promoter: De Boeck Hans

Research team(s)

• Plant and Ecosystems (PLECO) - Ecology in a time of change

Project type(s)

• Research Project

Abstract

"Spatial ecology" is a rapidly developing discipline in ecosystem science. While some ecologists explore the significance of the spatial heterogeneity in the soil for plant communities, others concentrate on the consequences of the spatial pattern of the plants. However, no studies have to our knowledge investigated how these two fundamental types of spatial heterogeneity work together in determining ecosystem functioning. Here we manipulate both types independently in mesocosms (simplified experimental ecosystems constructed from soil and plants), while additionally varying also species richness. Soil heterogeneity is experimentally varied in three dimensions with a novel technique. We also investigate the importance of heterogeneity for climate change impact.

Researcher(s)

• Promoter: Nijs Ivan
• Co-promoter: De Boeck Hans

Research team(s)

• Plant and Ecosystems (PLECO) - Ecology in a time of change

Project type(s)

• Research Project

Abstract

We are applying for the financing of a set-up enabling research into the impact of heat waves and droughts on plant systems. Extreme climate events can have a disproportionate impact on ecosystems relative to the temporal scale over which they occur, yet research on this highly relevant topic is still underdeveloped. The lack of studies addressing important excrescences of global change such as heat waves, is to a substantial part caused by the inability to recreate high temperature events in a realistic manner. Infrared heating has been identified as the most appropriate tool for imposing heat waves in the field, but the control mechanism to do this in a realistic manner has only recently been developed (by the applicant). The requested funds from the current proposal serve to build a set-up incorporating the infrared technique and the aforementioned novel control mechanism, in order to start up a project on the role of biodiversity in buffering the impacts of climate extremes. We are convinced that the set-up will grow into a platform which can be used in any experimental climate warming study, and that it will be a catalyst for our research group amid the current emerging attention into climate extremes.

Researcher(s)

• Promoter: De Boeck Hans

Research team(s)

• Plant and Ecosystems (PLECO) - Ecology in a time of change

Project type(s)

• Research Project

Abstract

Discrete climate events such as heat waves and droughts can have a disproportionate impact on ecosystems relative to the temporal scale over which they occur. The ultimate impact on the plant system is thought to depend on community properties such as the number of species and the species characteristics, although the few existing studies show contradicting results. Aided by experience gained on both climate extreme and biodiversity experiments throughout my scientific carreer, we propose a project to (i) predict the impact (damage) of heat waves and/or droughts based on the dominant plant interactions in an ecosystem and the species-specific traits; (ii) determine the potential of biodiversity in buffering negative effects of climate extremes; (iii) assess the risk of a possible acceleration of the spread of non-native plant species in a climate with more extreme events. Research will be conducted both on an experimental site and in the field, using an established method for creating droughts and a state-of-the-art technique for imposing heat waves. The project will increase understanding of ecosystem functioning, the importance of biodiversity and the significance of individual species, with relevance for fundamental ecology (e.g. improving ecosystem models) and nature conservation (e.g. identifying potentially vulnerable ecosystems).

Researcher(s)

• Promoter: Nijs Ivan
• Fellow: De Boeck Hans

Research team(s)

• Plant and Ecosystems (PLECO) - Ecology in a time of change

Project type(s)

• Research Project

Abstract

EXPEER will bring together, major observational, experimental, analytical and modelling facilities in ecosystem science in Europe. By uniting these highly instrumented ecosystem research facilities under the same umbrella and with a common vision, EXPEER will form a key contribution to structuring and improving the European Research Area (ERA) within terrestrial ecosystem research.

Researcher(s)

• Promoter: Nijs Ivan
• Co-promoter: De Boeck Hans

Research team(s)

• Plant and Ecosystems (PLECO) - Ecology in a time of change

Project type(s)

• Research Project

Abstract

In an ongoing, largely unfinanced experiment concerning the impact of climatic extremes on plant communities, an accurate automated system of moisture sensors for the invastigation of water relations is lacking. KP financing for the purchase of 44 of these sensors + wiring, would fill this important void in the ongoing research.

Researcher(s)

• Promoter: De Boeck Hans

Research team(s)

• Plant and Ecosystems (PLECO) - Ecology in a time of change

Project type(s)

• Research Project

Abstract

The three main research questions are: - What is the separate and the combined influence of heat and drought extremes on grassland communities, and how do the responses differ seasonally? - How do plants respond to a climate with multiple periods of exceptional heat and/or drought in the same year, and how important is the time (recovery period) between such repeated extremes? - How important are the plants' interactions with its neighbours (con- or interspecific) in stress responses, and how do competitive interactions change because of extremes?

Researcher(s)

• Promoter: Nijs Ivan
• Fellow: De Boeck Hans

Research team(s)

• Plant and Ecosystems (PLECO) - Ecology in a time of change

Project type(s)

• Research Project

Abstract

Several native plant species of Mediterranean-arid ecosystems naturally fix winblown materials in small, stable, phytogenic mounds or `nebkhas', but none of them are currently used to combat desertification. In this project we screen a variety of such species, not only for sand stabilisation, but also to promote biodiversity by creating habitats for other species, since nebkhas locally improve soil fertility and water status. The project explores the potential of a new, natural rehabilitation technique to control the leakage of scarce resources from degraded arid landscapes.

Researcher(s)

• Promoter: Nijs Ivan
• Fellow: De Boeck Hans

Research team(s)

• Plant and Ecosystems (PLECO) - Ecology in a time of change

Project type(s)

• Research Project

Abstract

Several native plant species of Mediterranean-arid ecosystems naturally fix winblown materials in small, stable, phytogenic mounds or `nebkhas', but none of them are currently used to combat desertification. In this project we screen a variety of such species, not only for sand stabilisation, but also to promote biodiversity by creating habitats for other species, since nebkhas locally improve soil fertility and water status. The project explores the potential of a new, natural rehabilitation technique to control the leakage of scarce resources from degraded arid landscapes.

Researcher(s)

• Promoter: Nijs Ivan
• Fellow: De Boeck Hans

Research team(s)

• Plant and Ecosystems (PLECO) - Ecology in a time of change

Project type(s)

• Research Project

Abstract

Because greenhouse gas concentrations in the earth's atmosphere continue to rise, the probability of significant climate change increases (IPCC, 2001a). There have been many studies concerning the effects of elevated CO2 concentrations on terrestrial ecosystems, and, to a lesser extent, the influence of higher temperatures. Another aspect of global change, declining biodiversity, is less well studied. This project investigates the single-factor and combined impact of elevated temperatures and diversity loss. Future carbon budgets will be the reflection of antagonisms and synergies between these 2 critical drivers of carbon sequestration, but studies of interactions are almost non-existent. The study uses artificially assembled grassland model ecosystems. In twelve sunlit, climate-controlled chambers at the UIA campus (F.W.O. project), half of the model ecosystems are subjected to a temperature increase of 3°C. In each chamber, 24 plant communities are grown containing either 1, 3 or 9 grassland species. The design of the growth chambers is multi-factorial, and contains all combinations of temperature and diversity, in 6 replicates. The study consists of 3 sections: (i) Carbon flux measurements and study of storage and turnover of soil carbon: CO2-flux measurements enable us to quantify inputs through photosynthesis and outputs through aboveground and belowground respiration. Because these fluxes cannot be measured continuously, they are recontructed from discrete measurements by interpolation, based on the relationships of the C-balance components with their dominant drivers (mainly radiation or temperature). To this end we use infrared gas analysis in dynamic closed systems. Soil carbon storage and turnover are analysed by d13C measurements of CO2 produced in the soil. Because C3 plants are grown on C4 soils, it is possible to separate soil respiration into root and microbial respiration. (ii) Ecophysiological measurements: Ecophysiological parameters will change in response to the 3 conditions simulated in this project (temperature increase, biodiversity change, and both), which can provide explanations for observed shifts in the carbon balance. We study (among other things) how stomatal resistance, nutrient uptake and nutrient use efficiency, and canopy temperature react to the induced changes. (iii) Study of phenology and competition: Changes in phenology can also have a large impact on the carbon balance, and temperature is an important factor in determining both the beginning and the end of the growing season. We are therefore monitoring changes in both the length and the dynamics of the growing season under conditions of elevated temperatures (and declining plant diversity), both in individual species and species assemblages. We are furthermore investigating alterations in species composition and we attempt to identify the type of plant characteristics that are favoured by exposure to the various factors of global change. These findings are linked to any observed changes in carbon fluxes.

Researcher(s)

• Promoter: Nijs Ivan
• Fellow: De Boeck Hans

Research team(s)

Project type(s)

• Research Project