{"type": "FeatureCollection", "features": [{"id": "10.1016/j.biombioe.2018.10.004", "type": "Feature", "geometry": null, "properties": {"updated": "2026-05-25T16:15:35Z", "type": "Journal Article", "created": "2018-10-11", "title": "How and why does willow biochar increase a clay soil water retention capacity?", "description": "Abstract Addition of biochar into a soil changes its water retention properties by modifying soil textural and structural properties. In addition, internal micrometer-scale porosity that is able to directly store readily plant available water affects soil water retention properties. This study shows how precise knowledge of the internal micrometer-scale pore size distribution of biochar can deepen the understanding of the biochar-water interactions in soils. The micrometer-scale porosity of willow biochar was quantitatively and qualitatively characterized using X-ray tomography, 3D image analysis and Helium ion microscopy. The effect of biochar application on clay soil water retention was studied by conventional water retention curve approach. The results indicate that the internal pores of biochar, with sizes of at 50 and 10\u202f\u03bcm (equivalent pore diameter), increased soil porosity and the amount of readily plant available water. After biochar addition, changes in soil porosity were detected at pore size regimes 5\u201310 and 25\u202f\u03bcm, i.e. biochar pore sizes multiplied by factor 0.5. The detected pore size distribution of biochar does not predict directly (1:1 compatibility) the changes observed in the soil moisture characteristics. It is likely that biochar chemistry and pore morphology affect biochar-water interactions via e.g. surface roughness and contact angle. In addition, biochar induced changes in soil structure and texture affected soil moisture characteristics. However, the approach presented is an attractive pathway to more generalized understanding on how and why biochar internal porosity affects soil moisture characteristics.", "keywords": ["570", "Fysiikka", "ta1171", "mikroskopia", "savi", "01 natural sciences", "630", "huokoisuus", "soil water retention", "tomografia", "219", "3D image analysis", "biochar", "3D-mallinnus", "ta216", "ta218", "219 Environmental biotechnology", "0105 earth and related environmental sciences", "x-ray tomography", "biohiili", "maaper\u00e4", "ta114", "Physics", "ta1182", "04 agricultural and veterinary sciences", "15. Life on land", "6. Clean water", "mikrorakenteet", "plant available water", "helium ion microscopy", "0401 agriculture", " forestry", " and fisheries", "vesipitoisuus", "X-ray tomography"]}, "links": [{"href": "https://doi.org/10.1016/j.biombioe.2018.10.004"}, {"rel": "related", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/Biomass%20and%20Bioenergy", "name": "related record", "description": "related record", "type": "application/json"}, {"rel": "self", "type": "application/geo+json", "title": "10.1016/j.biombioe.2018.10.004", "name": "item", "description": "10.1016/j.biombioe.2018.10.004", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.1016/j.biombioe.2018.10.004"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2018-12-01T00:00:00Z"}}, {"id": "10.1016/j.jaap.2018.07.011", "type": "Feature", "geometry": null, "properties": {"updated": "2026-05-25T16:16:23Z", "type": "Journal Article", "created": "2018-07-20", "title": "Effects of pyrolysis temperature on the hydrologically relevant porosity of willow biochar", "description": "Open AccessBiochar pore space consists of porosity of multiple length scales. In direct water holding applications like water storage for plant water uptake, the main interest is in micrometre-range porosity since these pores are able to store water that is easily available for plants. Gas adsorption measurements which are commonly used to characterize the physical pore structure of biochars are not able to quantify this pore-size range. While pyrogenetic porosity (i.e. pores formed during pyrolysis process) tends to increase with elevated process temperature, it is uncertain whether this change affects the pore space capable to store plant available water. In this study, we characterized biochar porosity with x-ray tomography which provides quantitative information on the micrometer-range porosity. We imaged willow dried at 60 $^ circ$C and biochar samples pyrolysed in three different temperatures (peak temperatures 308, 384, 489 $^ circ$C, heating rate 2 $^ circ$C min$^{-1}$). Samples were carefully prepared and traced through the experiments, which allowed investigation of porosity development in micrometre size range. Pore space was quantified with image analysis of x-ray tomography images and, in addition, nanoscale porosity was examined with helium ion microscopy. The image analysis results show that initial pore structure of the raw material determines the properties of micrometre-range porosity in the studied temperature range. Thus, considering the pore-size regime relevant to the storage of plant available water, pyrolysis temperature in the studied range does not provide means to optimize the biochar structure. However, these findings do not rule out that process temperature may affect the water retention properties of biochars by modifying the chemical properties of the pore surfaces.", "keywords": ["Fysiikka", "porosity", "FOS: Physical sciences", "Applied Physics (physics.app-ph)", "kuivatislaus", "01 natural sciences", "huokoisuus", "image analysis", "biochar", "ta216", "ta218", "0105 earth and related environmental sciences", "x-ray tomography", "biohiili", "Condensed Matter - Materials Science", "ta114", "Physics", "ta1182", "Materials Science (cond-mat.mtrl-sci)", "Physics - Applied Physics", "04 agricultural and veterinary sciences", "slow pyrolysis", "6. Clean water", "kuvantaminen", "kuva-analyysi", "0401 agriculture", " forestry", " and fisheries"]}, "links": [{"href": "https://doi.org/10.1016/j.jaap.2018.07.011"}, {"rel": "related", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/Journal%20of%20Analytical%20and%20Applied%20Pyrolysis", "name": "related record", "description": "related record", "type": "application/json"}, {"rel": "self", "type": "application/geo+json", "title": "10.1016/j.jaap.2018.07.011", "name": "item", "description": "10.1016/j.jaap.2018.07.011", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.1016/j.jaap.2018.07.011"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2018-09-01T00:00:00Z"}}, {"id": "10.1029/2020wr028624", "type": "Feature", "geometry": null, "properties": {"updated": "2026-05-25T16:17:32Z", "type": "Journal Article", "created": "2021-06-21", "title": "Hydraulic and Physical Properties of Managed and Intact Peatlands: Application of the Van Genuchten\u2010Mualem Models to Peat Soils", "description": "Abstract

Undisturbed peatlands are effective carbon sinks and provide a variety of ecosystem services. However, anthropogenic disturbances, especially land drainage, strongly alter peat soil properties and jeopardize the benefits of peatlands. The effects of disturbances should therefore be assessed and predicted. To support accurate modeling, this study determined the physical and hydraulic properties of intact and disturbed peat samples collected from 59 sites (in total 3,073 samples) in Finland and Norway. The bulk density (BD), porosity, and specific yield (Sy) values obtained indicated that the top layer (0\uffe2\uff80\uff9330\uffc2\uffa0cm depth) at agricultural and peat extraction sites was most affected by land use change. The BD in the top layer at agricultural, peat extraction, and forestry sites was 441%, 140%, and 92% higher, respectively, than that of intact peatlands. Porosity decreased with increased BD, but not linearly. Agricultural and peat extraction sites had the lowest saturated hydraulic conductivity, Sy, and porosity, and the highest BD of the land use options studied. The van Genuchten\uffe2\uff80\uff90Mualem (vGM) soil water retention curve (SWRC) and hydraulic conductivity (K) models proved to be applicable for the peat soils tested, providing values of SWRC, K, and vGM\uffe2\uff80\uff90parameters (\uffce\uffb1 and n) for peat layers (top, middle and bottom) under different land uses. A decrease in peat soil water content of \uffe2\uff89\uffa510% reduced the unsaturated K values by two orders of magnitude. This unique data set can be used to improve hydrological modeling in peat\uffe2\uff80\uff90dominated catchments and for fuller integration of peat soils into large\uffe2\uff80\uff90scale hydrological models.Undisturbed peatlands are effective carbon sinks and provide a variety of ecosystem services. However, anthropogenic disturbances, especially land drainage, strongly alter peat soil properties and jeopardize the benefits of peatlands. The effects of disturbances should therefore be assessed and predicted. To support accurate modeling, this study determined the physical and hydraulic properties of intact and disturbed peat samples collected from 59 sites (in total 3,073 samples) in Finland and Norway. The bulk density (BD), porosity, and specific yield (Sy) values obtained indicated that the top layer (0\uffe2\uff80\uff9330\uffc2\uffa0cm depth) at agricultural and peat extraction sites was most affected by land use change. The BD in the top layer at agricultural, peat extraction, and forestry sites was 441%, 140%, and 92% higher, respectively, than that of intact peatlands. Porosity decreased with increased BD, but not linearly. Agricultural and peat extraction sites had the lowest saturated hydraulic conductivity, Sy, and porosity, and the highest BD of the land use options studied. The van Genuchten\uffe2\uff80\uff90Mualem (vGM) soil water retention curve (SWRC) and hydraulic conductivity (K) models proved to be applicable for the peat soils tested, providing values of SWRC, K, and vGM\uffe2\uff80\uff90parameters (\uffce\uffb1 and n) for peat layers (top, middle and bottom) under different land uses. A decrease in peat soil water content of \uffe2\uff89\uffa510% reduced the unsaturated K values by two orders of magnitude. This unique data set can be used to improve hydrological modeling in peat\uffe2\uff80\uff90dominated catchments and for fuller integration of peat soils into large\uffe2\uff80\uff90scale hydrological models.