{"type": "FeatureCollection", "features": [{"id": "10.1007/s11104-012-1411-4", "type": "Feature", "geometry": null, "properties": {"updated": "2026-06-24T16:15:48Z", "type": "Journal Article", "created": "2012-08-14", "title": "Biochar Application Reduces Nodulation But Increases Nitrogenase Activity In Clover", "description": "Background and aims: Biochar is produced from the pyrolysis of organic materials, and when buried in soil can act as a long term soil carbon (C) store. Evidence suggests that biochar can also increase crop yields, reduce nutrient leaching and increase biological nitrogen fixation in leguminous plants. However, the potential for increasing biological N2 fixation in agroecosystems is poorly understood, with inconsistent reports of root nodulation following biochar application. Therefore, the aim of this study was to determine the effect of biochar application rate and time since application on nodulation and nitrogenase activity in nodules of clover grown in a temperate agricultural soil. Methods: We used replicated field plots with three biochar application rates (0, 25 and 50 t ha-1). Three years after biochar amendment, the plots were further split and fresh biochar added at two different rates (25 and 50 t ha-1) resulting in double-loaded reapplications of 25&thinsp;+&thinsp;25 and 50&thinsp;+&thinsp;50 t ha-1. Results: Three years after biochar application, there was no significant difference in the total number of root nodules between biochar-amended and unamended soil, regardless of the application rate. However, despite clover root nodules being of a similar number and size the level of nitrogenase activity of individual nodules in biochar-amended soil was significantly higher than in unamended soil. Reapplication of biochar resulted in decreased nodulation, although the rate of nitrogenase activity per nodule remained unaffected. Conclusion: In the short term, biochar influences root nodule number and localised N2 fixation per nodule; however, total nitrogenase activity for the whole root system remained unaffected by the application rate of biochar or time since its application. These results emphasise the importance of long-term field studies, with a variety of applications rates for determining the influence of biochar applications on N2-fixing organisms and in providing data that can meaningfully inform agronomic management decisions and climate change mitigation strategies.", "keywords": ["Carbon sequestration", "2. Zero hunger", "Climate change mitigation", "Legume-Rhizobia symbiosis", "13. Climate action", "Black nitrogen", "0401 agriculture", " forestry", " and fisheries", "Biological nitrogen fixation", "04 agricultural and veterinary sciences", "15. Life on land", "630", "Long term biochar trial", "6. Clean water"]}, "links": [{"href": "http://dspace.stir.ac.uk/bitstream/1893/18417/1/Plant%20Soil%202013.pdf"}, {"href": "https://doi.org/10.1007/s11104-012-1411-4"}, {"rel": "related", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/Plant%20and%20Soil", "name": "related record", "description": "related record", "type": "application/json"}, {"rel": "self", "type": "application/geo+json", "title": "10.1007/s11104-012-1411-4", "name": "item", "description": "10.1007/s11104-012-1411-4", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.1007/s11104-012-1411-4"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2012-08-15T00:00:00Z"}}, {"id": "10.1016/j.agee.2012.06.011", "type": "Feature", "geometry": null, "properties": {"updated": "2026-06-24T16:16:09Z", "type": "Journal Article", "created": "2012-07-08", "title": "Nutrient Dynamics, Microbial Growth And Weed Emergence In Biochar Amended Soil Are Influenced By Time Since Application And Reapplication Rate", "description": "Evidence suggests that in addition to sequestering carbon (C), biochar amendment can increase crop yields, improve soil quality and nutrient cycling, reduce the leaching of nutrients from soil and stimulate soil microbial activity. However, biochar application primarily benefits soils of intrinsic poor quality, thus the advantages of adding biochar to temperate agricultural soils remains controversial. In addition, there is limited information about the longer term effects of biochar application, or of increasing the rate of biochar loading to soil. Therefore, the aim of this study was to determine the effect of biochar residency time and application rate on soil quality, crop performance, weed emergence, microbial growth and community composition in a temperate agricultural soil. We used replicated field plots with three wood biochar application rates (0, 25 and 50 t ha(-1)). Three years after biochar amendment, the plots were further split and fresh biochar added at two different rates (25 and 50 t ha(-1)) resulting in double-loaded reapplications of 25 + 25 and 50 + 50 t ha(-1). After a soil residency time of three years, there were no significant differences in soil nutrients, microbial growth, mycorrhizal colonisation or weed emergence between biochar amended and unamended soil. In contrast, the reapplication of biochar had a significant effect on soil quality, (e.g. increased PO43-, K+ and Ca2+, DOC, soil moisture, organic matter and EC), microbial growth, (e.g. decreased saprophytic fungal growth), increased mycorrhizal root colonisation and inhibition of weed emergence. Whilst biochar application is unquestionably a strategy for the sequestration of C, in this case, other benefits, e.g. improved soil nutrient levels or crop performance, seemed to be short lived. Reapplication of biochar exemplifies the transient nature of biochar-mediated benefits rather than any lasting differences in soil nutrient dynamics or microbial communities. These results emphasise the need for more long-term field studies to provide data that can meaningfully inform agronomic management decisions and climate change mitigation strategies. (C) 2012 Elsevier B.V. All rights reserved. (Less)", "keywords": ["Carbon sequestration", "2. Zero hunger", "Black carbon", "Repeat biochar application", "13. Climate action", "Temperate agriculture", "15. Life on land", "Long term biochar trial", "630", "6. Clean water"]}, "links": [{"href": "https://doi.org/10.1016/j.agee.2012.06.011"}, {"rel": "related", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/Agriculture%2C%20Ecosystems%20%26amp%3B%20Environment", "name": "related record", "description": "related record", "type": "application/json"}, {"rel": "self", "type": "application/geo+json", "title": "10.1016/j.agee.2012.06.011", "name": "item", "description": "10.1016/j.agee.2012.06.011", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.1016/j.agee.2012.06.011"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2012-09-01T00:00:00Z"}}], "links": [{"rel": "self", "type": "application/geo+json", "title": "This document as GeoJSON", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items?keywords=Long+term+biochar+trial&f=json", "hreflang": "en-US"}, {"rel": "alternate", "type": "text/html", "title": "This document as HTML", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items?keywords=Long+term+biochar+trial&f=html", "hreflang": "en-US"}, {"rel": "collection", "type": "application/json", "title": "Collection URL", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main", "hreflang": "en-US"}, {"type": "application/geo+json", "rel": "first", "title": "items (first)", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items?keywords=Long+term+biochar+trial&", "hreflang": "en-US"}, {"rel": "last", "type": "application/geo+json", "title": "items (last)", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items?keywords=Long+term+biochar+trial&offset=2", "hreflang": "en-US"}], "numberMatched": 2, "numberReturned": 2, "distributedFeatures": [], "timeStamp": "2026-06-25T05:20:08.209534Z"}