{"type": "FeatureCollection", "features": [{"id": "10.1007/s10533-015-0157-5", "type": "Feature", "geometry": null, "properties": {"updated": "2026-06-23T16:15:20Z", "type": "Journal Article", "created": "2015-11-14", "title": "Chronic Nitrogen Fertilization And Carbon Sequestration In Grassland Soils: Evidence Of A Microbial Enzyme Link", "description": "Chronic nitrogen (N) fertilization can greatly affect soil carbon (C) sequestration by altering biochemical interactions between plant detritus and soil microbes. In lignin-rich forest soils, chronic N additions tend to increase soil C content partly by decreasing the activity of lignin-degrading enzymes. In cellulose-rich grassland soils it is not clear whether cellulose-degrading enzymes are also inhibited by N additions and what consequences this might have on changes in soil C content. Here we address whether chronic N fertilization has affected (1) the C content of light versus heavier soil fractions, and (2) the activity of four extracellular enzymes including the C-acquiring enzyme \u03b2-1,4-glucosidase (BG; necessary for cellulose hydrolysis). We found that 19\u00a0years of chronic N-only addition to permanent grassland have significantly increased soil C sequestration in heavy but not in light soil density fractions, and this C accrual was associated with a significant increase (and not decrease) of BG activity. Chronic N fertilization may increase BG activity because greater N availability reduces root C:N ratios thus increasing microbial demand for C, which is met by C inputs from enhanced root C pools in N-only fertilized soils. However, BG activity and total root mass strongly decreased in high pH soils under the application of lime (i.e. CaCO3), which reduced the ability of these organo-mineral soils to gain more C per units of N added. Our study is the first to show a potential \u2018enzyme link\u2019 between (1) long-term additions of inorganic N to grassland soils, and (2) the greater C content of organo-mineral soil fractions. Our new hypothesis is that the \u2018enzyme link\u2019 occurs because (a) BG activity is stimulated by increased microbial C demand relative to N under chronic fertilization, and (b) increased BG activity causes more C from roots and from microbial metabolites to accumulate and stabilize into organo-mineral C fractions. We suggest that any combination of management practices that can influence the BG \u2018enzyme link\u2019 will have far reaching implications for long-term C sequestration in grassland soils.", "keywords": ["DECOMPOSITION", "DYNAMICS", "570", "\u03b2-1", "4-Glucosidase", "/dk/atira/pure/subjectarea/asjc/2300/2304", "NUTRIENT RELEASE", "Environmental Sciences & Ecology", "Root C:N ratio", "Extracellular enzyme activity", "LITTER DECAY", "FOREST ECOSYSTEMS", "0399 Other Chemical Sciences", "0402 Geochemistry", "Environmental Chemistry", "Geosciences", " Multidisciplinary", "beta-1", "4-Glucosidase", "Earth-Surface Processes", "Water Science and Technology", "2. Zero hunger", "Multidisciplinary", "Science & Technology", "/dk/atira/pure/subjectarea/asjc/1900/1904", "Geology", "sequestration", "Agronomy & Agriculture", "04 agricultural and veterinary sciences", "15. Life on land", "Soil carbon", "N DEPOSITION", "ORGANIC-MATTER", "PHOSPHORUS", "Fertilization", "Physical Sciences", "N ratio [Root C]", "0401 agriculture", " forestry", " and fisheries", "Soil carbon sequestration", "Liming", "TURNOVER", "Life Sciences & Biomedicine", "Geosciences", "/dk/atira/pure/subjectarea/asjc/2300/2312", "Environmental Sciences", "RESPONSES"]}, "links": [{"href": "https://doi.org/10.1007/s10533-015-0157-5"}, {"rel": "related", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/Biogeochemistry", "name": "related record", "description": "related record", "type": "application/json"}, {"rel": "self", "type": "application/geo+json", "title": "10.1007/s10533-015-0157-5", "name": "item", "description": "10.1007/s10533-015-0157-5", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.1007/s10533-015-0157-5"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2015-11-14T00:00:00Z"}}, {"id": "10.1007/s11270-021-05044-z", "type": "Feature", "geometry": null, "properties": {"updated": "2026-06-23T16:15:39Z", "type": "Journal Article", "created": "2021-03-02", "title": "Holistic Assessment of Biochar and Brown Coal Waste as Organic Amendments in Sustainable Environmental and Agricultural Applications", "description": "Abstract

Organic amendments can improve soil quality which has knock-on environmental and agronomic benefits. However, the use of new and emerging organic amendments such as biochar and brown coal waste (BCW) in soil systems requires continuous holistic assessments for robust consensus building in their environmental and agricultural applications. To examine the application of BCW and woodchip biochar (BIO) in agroecosystems, secondary data from literature on environmental (soil, air and water) aspects were compiled with primary agronomic data from a 3-year multicropping field trial and collated with supplementary data on economic factors (e.g. cost and availability). For the field trial, replicated plots were amended with FYM (for comparative reasons), BCW and BIO at 30, 24.2 and 12.8 for t ha\uffe2\uff80\uff931, respectively, with and without NPK and cultivated in a cropping sequence of maize, potato and barley. At the end of each season, soils were characterised for pH, cation exchange capacity (CEC) and fertility (macronutrient contents) in addition to nutrient uptake, nutritional quality and yield of crops. Compared with FYM, biochar and BCW were found to be associated with greater improvements in soil quality (e.g. building of soil structure and C sequestration) and knock-on water and air quality benefits mainly facilitated via increased cation retention and humic-linked sorption which abated gaseous emission and mitigated nutrient and heavy metal leaching. These along with variable improvements in soil chemistry, fertility and nutrient uptake in the agronomic field trial accounted for increased mean crop yield across treatments (higher with NPK): FYM (32.7 and 71.7%), BCW (33.5 and 60.1%) and BIO (21.8 and 48.2%). Additionally, biochar and BCW have lower pollutant (e.g. heavy metals) contents and were found to provide additional sustainability and net abatement cost-benefits. While the agronomic benefits of biochar and BCW were slightly lower compared with that of FYM, their lower environmental footprints and associated sustainability benefits are clear advantages for their adoption in environmental and agricultural applications. beech = spruce; all data in mg CO2\u2013C m\u22122 h\u22121). Secondly, we studied decomposition after fourfold litter manipulations at the 6 mixed species stands: the Oi \u2013 and Oe horizons were removed and replaced by additions of beech \u2013, spruce \u2013 and mixed litter of the adjacent pure stands of known chemical quality and one zero addition (blank) in open rings (20 cm inner diameter), which were covered with meshes to exclude fresh litter fall. Mass loss within two years amounted to 61\u201368% on Flysch and 36\u201344% on Molasse, indicating non-additive mixed species effects (mixed litter showed highest mass loss). However, base cation release showed a linear response, increasing from the spruce \u2013 over the mixed \u2013 to the beech litter. The differences in N release (immobilization) resulted in a characteristic converging trend in C/N ratios for all litter compositions on both bedrocks during decomposition. In the summers 2006 and 2007 we measured CO2 efflux from these manipulated areas (a closed chamber fits exactly over such a ring) as field indicator of the microbial activity. Net fluxes (subtracting the so-called blank values) are considered an indicator of litter induced changes only and increased on both bedrocks from the spruce \u2013 over the mixed \u2013 to the beech litter. According to these measurements, decomposing litter contributed between 22\u201332% (Flysch) and 11\u201328% (Molasse) to total soil respiration, strengthening its role within the global carbon cycle.", "keywords": ["DYNAMICS", "0106 biological sciences", "FLUXES", "Fagus sylvatica", "NUTRIENT RELEASE", "BROADLEAF", "Nutrient cycling", "01 natural sciences", "Mixed species effects", "507015 Regionalforschung", "FORESTS", "FAGUS-SYLVATICA", "CO(2) efflux", "SDG 15 \u2013 Leben an Land", "SDG 15 - Life on Land", "Picea abies", "Litter decomposition", "NORWAY SPRUCE", "04 agricultural and veterinary sciences", "15. Life on land", "PICEA-ABIES", "RESPIRATION", "13. Climate action", "507015 Regional research", "0401 agriculture", " forestry", " and fisheries", "LEAF-LITTER"]}, "links": [{"href": "https://doi.org/10.1016/j.soilbio.2010.02.020"}, {"rel": "related", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/Soil%20Biology%20and%20Biochemistry", "name": "related record", "description": "related record", "type": "application/json"}, {"rel": "self", "type": "application/geo+json", "title": "10.1016/j.soilbio.2010.02.020", "name": "item", "description": "10.1016/j.soilbio.2010.02.020", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.1016/j.soilbio.2010.02.020"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2010-06-01T00:00:00Z"}}, {"id": "10.1023/a:1004868502539", "type": "Feature", "geometry": null, "properties": {"updated": "2026-06-23T16:18:08Z", "type": "Journal Article", "title": "Leaf Litter Decomposition Of Piper Aduncum, Gliricidia Sepium And Imperata Cylindrica In The Humid Lowlands Of Papua New Guinea", "description": "No information is available on the decomposition and nutrient release pattern of Piper aduncum and Imperata cylindrica despite their importance in shifting cultivation systems of Papua New Guinea and other tropical regions. We conducted a litter bag study (24 weeks) on a Typic Eutropepts in the humid lowlands to assess the rate of decomposition of Piper aduncum, Imperata cylindrica and Gliricidia sepium leaves under sweet potato (Ipomoea batatas). Decomposition rates of piper leaf litter were fastest followed closely by gliricidia, and both lost 50% of the leaf biomass within 10 weeks. Imperata leaf litter decomposed much slower and half-life values exceeded the period of observation. The decomposition patterns were best explained by the lignin plus polyphenol over N ratio which was lowest for piper (4.3) and highest for imperata (24.7). Gliricidia leaf litter released 79 kg N ha(-1), whereas 18 kg N ha(-1) was immobilised in the imperata litter. The mineralization of P was similar for the three species, but piper litter released large amounts of K. The decomposition and nutrient release patterns had significant effects on the soil. The soil contained significantly more water in the previous imperata plots at 13 weeks due to the relative slow decomposition of the leaves. Soil N levels were significantly reduced in the previous imperata plots due to immobilisation of N. Levels of exchangeable K were significantly increased in the previous piper plots due to the large addition of K. It can be concluded that piper leaf litter is a significant and easily decomposable source of K which is an important nutrient for sweet potato. Gliricidia leaf litter contained much N, whereas imperata leaf litter releases relatively little nutrients and keeps the soil more moist. Gliricidia fallow is more attractive than an imperata fallow for it improves the soil fertility and produces fuelwood as additional saleable products.", "keywords": ["Polyphenol", "Tropical Legumes", "Leaves", "tropical legumes", "Soil Science", "Nitrogen Mineralization", "Lignin", "n-release", "soil", "Soil", "residues", "C1", "Soil Changes", "nitrogen mineralization", "Chemical-composition", "580", "nutrient release", "Plant Sciences", "Sweet-potato", "Agriculture", "Residues", "Quality", "Agronomy", "Improved Fallow", "quality", "Natural Fallow", "sweet-potato", "Nutrient Release", "300104 Land Capability and Soil Degradation", "chemical-composition", "leaves", "N-release", "770800 Farmland (incl. Arable Land and Permanent Crop Land)"]}, "links": [{"href": "https://doi.org/10.1023/a:1004868502539"}, {"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": "10.1023/a:1004868502539", "name": "item", "description": "10.1023/a:1004868502539", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.1023/a:1004868502539"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2001-01-01T00:00:00Z"}}], "links": [{"rel": "self", "type": "application/geo+json", "title": "This document as GeoJSON", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items?keywords=NUTRIENT+RELEASE&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=NUTRIENT+RELEASE&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=NUTRIENT+RELEASE&", "hreflang": "en-US"}, {"rel": "last", "type": "application/geo+json", "title": "items (last)", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items?keywords=NUTRIENT+RELEASE&offset=4", "hreflang": "en-US"}], "numberMatched": 4, "numberReturned": 4, "distributedFeatures": [], "timeStamp": "2026-06-24T10:24:15.150708Z"}