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167 results on '"Van Hees, May"'

4. From crop left-overs to nutrient resource: growth-stimulating potential of biochar in nutrient solutions for wheat soilless cultivation systems.

Author

Kunnen, Kris, Ali, Md Muntasir, Lataf, Amine, Van Hees, May, Nauts, Robin, Horemans, Nele, Vandamme, Dries, and Cuypers, Ann

Subjects
WHEAT, HYDROPONICS, AGRICULTURE, CROP residues, WHEATGRASSES
Abstract

To reach the estimated food demands for 2050 in decreasingly suiting climates, current agricultural techniques have to be complemented by sustainably intensified practices. The current study repurposed wheat crop residues into biochar, and investigated its potential in different plant cultivation systems, including a hydroponic cultivation of wheat. Biochars resulting from varying pyrolysis parameters including feedstock composition (straw and chaff) and temperature (450°C and 600°C), were tested using a fast plant screening method. Biochar WBC450, produced from a combination of chaff and straw at 450°C, was selected for further plant experiments, and used in a static leaching experiment in the Arabidopsis thaliana cultivation medium. Increased pH and EC were observed, together with an increase of most macronutrient (K, Mg, P, S) and a decrease of most micronutrient (Fe, Mn, Zn) concentrations. Considering plant growth, application of biochar resulted in concentration-dependent effects in both tested plant species (A. thaliana and wheat). It improved the vegetative yield across all tested cultivation systems. Increases in K and S, and concentration-dependent decreases in Fe and Na content in wheatgrass were observed. Biochar influenced the reproduction of hydroponically cultivated wheat by increasing the number of spikes and the number of seeds per spike. The antioxidative capacity of wheat grass, and the seed sugar and starch contents remained unaffected by biochar application. This study contributes to innovation in soilless cultivation approaches of staple crops, within the framework of closing waste loops for a circular bioeconomy. [ABSTRACT FROM AUTHOR]

Published
2024
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35. Concentrations and distributions of Al, Ca, Cl, K, Mg and Mn in a Scotspine forest in Belgium

Author

UCL - SST/ELI/ELIE - Environmental Sciences, Gielen, Sienke, Vives i Batlle, Jordi, Vincke, Caroline, Van Hees, May, Vandenhove, Hildegarde, UCL - SST/ELI/ELIE - Environmental Sciences, Gielen, Sienke, Vives i Batlle, Jordi, Vincke, Caroline, Van Hees, May, and Vandenhove, Hildegarde

Abstract

A Pinus sylvestris stand located in Mol, Belgium was studied for its content of six elements: Ca, K, Mg, Al, Cland Mn. A fractionation of tree components was carried out into 8 classes (heart and sapwood, inner andouter bark, living branches, twigs and young/old needles) and their element contents were measured.Comparisons were made between the different compartments in terms of absolute and relative elementcontents. Quantitatively, Ca and K are the main elements: in young needles, Ca + K reach 83% of theelements’ whole stock. The wood compartments (heartwood + sapwood) have generally low elementcontent, as does the outer bark except for Ca (which is bound to suberin) and Al, possibly from atmosphericclay deposition. The inner bark, twigs and needles have high element contents possibly linked to highsymplasmic content. The Inner bark shows high Ca and K contents as these elements are involved inphloem transport. Positive correlations were found between Ca and Al, Mn and Cl, K and Cl and K andMn, attributed to similarity in chemical and biological function.A simple empirical compartment model was developed to derive numerically the transfer rates thatreproduce the element distribution within tree compartments. The calculated mass flows appear to bewithin range of the limited data available from other pine tree studies.This study highlights the potential for coupling of specific elements (including radionuclides) to Ca, K,Mg, Al, Cl and Mn in context of vegetation modelling, by assuming that these elements follow the samepathways. We found indication that36Cl,90Sr and137Cs (environmentally important from the perspectiveof nuclear power and waste management) can be coupled to Cl, Ca and K fluxes within the tree, increasingthe understanding of the cycling of radionuclides in a forest ecosystem.

Published
2016

39. Potential of four aquatic plant species to remove 60Co from contaminated water under changing experimental conditions.

Author

Vanhoudt, Nathalie, Van Ginneken, Patia, Nauts, Robin, and Van Hees, May

Subjects
AQUATIC plants, WATER pollution, LEMNA minor, WATER lettuce, PLANT species
Abstract

This study aimed to compare the potential of Lemna minor, Spirodela sp., Eichhornia crassipes and Pistia stratiotes to remove 60Co from a realistic aquatic environment. Although all four plant species performed similarly well after 3 days of exposure to 50 kBq L−1 60Co, Lemna minor and Spirodela sp. came forward as having higher 60Co removal potential. This conclusion is, in first instance, based on the high 60Co removal percentage obtained after a short contact time (e.g. more than 95% could be removed after 6 h by Spirodela sp.). Additionally, Lemna minor and Spirodela sp. accumulated a high amount of 60Co per gram of biomass. For example, Lemna minor accumulated over three times more 60Co per gram of biomass compared to Pistia stratiotes and Eichhornia crassipes. Both plants also performed well in the pH range 5-9. We used Lemna minor to test the influence of the initial 60Co concentration (10, 50, 100 and 200 kBq L−1 60Co) on its phytoremediation capacity but no differences could be observed in removal percentage. In addition, it was shown that by optimising the initial amount of biomass, radioactive waste production can be minimised whilst maintaining high 60Co removal rates. Our study shows that these aquatic plants can be used for phytoremediation of 60Co from contaminated water and can be considered as a “green” addition or alternative for conventional remediation techniques. [ABSTRACT FROM AUTHOR]

Published
2018
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47. Relevance of radiocaesium Interception Potential (RIP) on a worldwide scale to assess soil vulnerability to 137 Cs contamination.

Author

SCK-CEN, UCL - SST/ELI/ELIE - Environmental Sciences, VandeBroeck, Louis, Van Hees, May, Thiry, Yves, Delvaux, Bruno, Spaargaren, Otto, SCK-CEN, UCL - SST/ELI/ELIE - Environmental Sciences, VandeBroeck, Louis, Van Hees, May, Thiry, Yves, Delvaux, Bruno, and Spaargaren, Otto

Abstract

The extent of radiocaesium retention in soil is important to quantify the risk of further foodchain contamination. The Radiocaesium Interception Potential (RIP – Cremers et al., 1988, Nature 335, 247–249) is an intrinsic soil parameter which can be used to categorize soils or minerals in terms of their capacity to selectively adsorb radiocaesium. In this study, we measured RIP for a large soil collection (88 soil samples) representative of major FAO soil reference groups on a worldwide scale and tested the possibility to predict the RIP on the basis of other easily accessible or measurable soil data. We also compared RIP values with those obtained from separate chemical extraction experiments. The range of measured RIP values (1.8–13300 mmol kg−1) was shown to include nearly all possible cases of agricultural soil contamination. Only Podzols, Andosols and Ferralsols were clearly characterized by a very low RIP (<2000 mmol kg−1). On a worldwide scale, RIP was in fact slightly related to soil reference type or other simple major physicochemical parameters such as clay percentage or organic matter. Conversely our results indicated a link between the RIP and radiocaesium extractability across very different soils. We showed that, with the proposed scale of RIP values, a simple acid extraction method can provide an operational result highly predictive of potential RIP despite very contrasting soil properties. The RIP could be estimated from the empirical equation: RIP = (−31.701 ∗ log(AER) + 58.886)2 where AER is the fraction of acid-extractable radiocaesium.

Published
2012

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