{"type": "FeatureCollection", "features": [{"id": "10.1016/j.agee.2003.12.008", "type": "Feature", "geometry": null, "properties": {"updated": "2026-07-26T16:15:06Z", "type": "Journal Article", "created": "2004-02-05", "title": "Effects Of Forest Conversion To Pasture On Soil Carbon Content And Dynamics In Brazilian Amazonia", "description": "Abstract   Soils play an important role in the carbon cycle, and deforestation in the tropics affects both soil carbon storage and CO2 release into the atmosphere. The consequences of deforestation and conversion to pasture for soil carbon content and dynamics were examined in two soil types differing mainly by their texture. Two chronosequences were selected, each consisting of an intact forest and three pastures of different ages (4, 8, 15 years and 3, 9, 15 years, respectively). One chronosequence is located in the central part of the Brazilian Amazon basin, where the soils are clayey ferralsols, and the second in the Eastern Brazilian Amazon Basin, where the soils are sandy clayey acrisols. In the upper layer the C content of clayey soils was three times higher than in the sandy soils, but despite the differences in soil texture, the C distribution in the particle-size fractions was quite similar. In the two chronosequences, the conversion to pasture induced a slight increase in C content. Bulk density increases were greater on soils with lower clay contents. The       13   C    measurements, which allowed to calculate the distribution of C derived from forest and from pasture, showed that all the particle-size fractions incorporated C derived from pasture and that a significant proportion of the young organic matter is rapidly trapped in the finest fractions. Although the proportions of pasture-derived C were higher in the sandy soils than in the clayey soils, the amounts of pasture-derived C in the particle-size fractions were 2\u20133 times larger in the clayey soils than in the sandy soils.", "keywords": ["rain-forest", "550", "ZONE TROPICALE", "c-13 natural abundance", "TEXTURE", "[SDV.SA.SDS]Life Sciences [q-bio]/Agricultural sciences/Soil study", "630", "Carbon Cycle", "C-13 isotope", "Amazonia", "EVOLUTION DES SOLS SOUS CULTURE", "STRUCTURE DU SOL", "soil carbon storage", "particle-size fractions", "Pasture", "cultivated oxisols", "ANALYSE ISOTOPIQUE", "SABLE", "eastern amazonia", "Deforestation", "[SDV.SA.SDS] Life Sciences [q-bio]/Agricultural sciences/Soil study", "Acrisol", "2. Zero hunger", "tropical soils Organic-matter dynamics", "Brasil", "size-fractions", "PATURAGE", "turnover", "Soil Carbon", "04 agricultural and veterinary sciences", "South America", "15. Life on land", "CARBONE ORGANIQUE", "STOCK ORGANIQUE", "ARGILE", "0401 agriculture", " forestry", " and fisheries", "DEFORESTATION", "texture"], "contacts": [{"organization": "Desjardins, T., Barros, E., Sarrazin, M., Girardin, C., Mariotti, A.,", "roles": ["creator"]}]}, "links": [{"href": "https://doi.org/10.1016/j.agee.2003.12.008"}, {"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.2003.12.008", "name": "item", "description": "10.1016/j.agee.2003.12.008", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.1016/j.agee.2003.12.008"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2004-07-01T00:00:00Z"}}, {"id": "10.1016/j.geoderma.2004.02.014", "type": "Feature", "geometry": null, "properties": {"updated": "2026-07-26T16:16:07Z", "type": "Journal Article", "created": "2004-04-10", "title": "Conversion Of Grassy Cerrado Into Riparian Forest And Its Impact On Soil Organic Matter Dynamics In An Oxisol From Southeast Brazil", "description": "Abstract   The purpose of this study was to evaluate possible changes in soil organic matter (SOM) dynamics after establishing riparian forests on soils previously under Brazilian savannah (\u201ccerrado\u201d). We selected a site with a homogeneous Typic Acric Red\u2013Yellow Latosol (Anionic Acrustox). Part of this site was maintained under native vegetation (grassy cerrado C 4 -dominated), and part was planted with riparian species (C 3 ) in 1992. Litter and soil samples were collected and analysed (total organic carbon, total nitrogen,  \u03b4  13 C isotopic analysis, and SOM density fractionation). Due to the predominance of grasses, carbon input was mainly below ground in cerrado. In such a soil, the decomposition process was more efficient, and much C and N were transferred to the heavy fraction. When forest was planted, there was a change from belowground to aboveground litter input (largely superficial), leading to higher C and N stocks in the light and lower stocks in the heavy fraction (resulting in lower stocks for bulk soil). The introduction of the C 3  vegetation decreased the soil  \u03b4  13 C signature. It has occurred particularly in the topsoil (0\u20135 cm) due to the deposition of C 3  litter on the soil surface. At the same time, the presence of cerrado-remaining C below 5 cm maintained higher  \u03b4  13 C values in this layer. During the 8 years after forest plantation, the input mode influenced both the  \u03b4  13 C distribution with depth, and the C replacement: between 0 and 2.5 cm, nearly 50% of cerrado-derived C was replaced by forest-derived C, while below 5 cm, replacement was around 20%. The relatively rapid C dynamics in this Oxisol (27% replacement in the top 20 cm after 8 years of forest plantation) shows that, under tropical conditions, significant changes may occur in a short period of time.", "keywords": ["delta-c-13", "decomposition", "c-13 natural-abundance", "particle-size fractions", "turnover", "0401 agriculture", " forestry", " and fisheries", "vegetation changes", "04 agricultural and veterinary sciences", "15. Life on land", "stable carbon isotope", "density fractions", "ratios", "nitrogen"], "contacts": [{"organization": "de Alcantara, F.A., Buurman, P., Furtini Neto, A.E., Curi, N., Roscoe, R.,", "roles": ["creator"]}]}, "links": [{"href": "https://doi.org/10.1016/j.geoderma.2004.02.014"}, {"rel": "related", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/Geoderma", "name": "related record", "description": "related record", "type": "application/json"}, {"rel": "self", "type": "application/geo+json", "title": "10.1016/j.geoderma.2004.02.014", "name": "item", "description": "10.1016/j.geoderma.2004.02.014", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.1016/j.geoderma.2004.02.014"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2004-12-01T00:00:00Z"}}, {"id": "10.1590/s0100-06832009000600009", "type": "Feature", "geometry": null, "properties": {"license": "Open Access", "updated": "2026-07-26T16:19:35Z", "type": "Journal Article", "created": "2010-02-11", "title": "Carbon Content In Amazonian Oxisols After Forest Conversion To Pasture", "description": "<p>Soil plays an important role in the C cycle, and substitution of tropical forest by cultivated land affects C dynamic and stock. This study was developed in an area of expansion of human settlement in the Eastern Amazon, in Itupiranga, State of Par\uffc3\uffa1, to evaluate the effects of native forest conversion to Brachiaria brizantha pasture on C contents of a dystrophic Oxisol. Soil samples were collected in areas of native forest (NF), of 8 to 10 year old secondary forest (SF), 1 to 2 year old SF (P1-2), 5 to 7 year old SF (P5-7), and of 10 to 12 year old SF (P10-12), and from under pastures, in the layers 0-2, 2-5 and 5-10 cm, to evaluate C levels and stocks and carry out separation of OM based on particle size. After deforestation, soil density increased to a depth of 5 cm, with greater increase in older pastures. Variation in C levels was greatest in the top soil layer; C contents increased with increasing pasture age. In the layers 2-5 and 5-10 cm, C content proved to be stable for the types of plant cover evaluated. Highest C concentrations were found in the silt fraction; however, C contents were highest in the clay fraction, independent of the plant cover. An increase in C associated with the sand fraction in the form of little decomposed organic residues was observed in pastures, confirming greater sensitivity of this fraction to change in soil use.</p>", "keywords": ["estoque de carbono no solo", "550", "floresta amaz\u00f4nica", "particle-size fractions", "tropical soil", "0401 agriculture", " forestry", " and fisheries", "Amazon rain forest", "fracionamento granulom\u00e9trico", "solo tropical", "04 agricultural and veterinary sciences", "15. Life on land", "630", "soil carbon stock"], "contacts": [{"organization": "Silva da, M. L., /Desjardins, Thierry, /Sarrazin, Max, Melo de, V. S., Martins, P. F. D., Santos, E. R., Carvalho de, C. J. R.,", "roles": ["creator"]}]}, "links": [{"href": "https://doi.org/10.1590/s0100-06832009000600009"}, {"rel": "related", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/Revista%20Brasileira%20de%20Ci%C3%AAncia%20do%20Solo", "name": "related record", "description": "related record", "type": "application/json"}, {"rel": "self", "type": "application/geo+json", "title": "10.1590/s0100-06832009000600009", "name": "item", "description": "10.1590/s0100-06832009000600009", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.1590/s0100-06832009000600009"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2009-12-01T00:00:00Z"}}], "links": [{"rel": "self", "type": "application/geo+json", "title": "This document as GeoJSON", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items?keywords=particle-size+fractions&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=particle-size+fractions&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=particle-size+fractions&", "hreflang": "en-US"}, {"rel": "last", "type": "application/geo+json", "title": "items (last)", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items?keywords=particle-size+fractions&offset=3", "hreflang": "en-US"}], "numberMatched": 3, "numberReturned": 3, "distributedFeatures": [], "timeStamp": "2026-07-26T21:01:57.882245Z"}