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Dynamic soil processes on heathland due to changes in vegetation to oak and Sitka spruce / Knud Erik Nielsen in Forest Ecology and Management, vol. 114, n°1 (Année 1999)

Public [article]  inForest Ecology and Management > vol. 114, n°1 (Année 1999) . - pp. 107-116 Titre : Dynamic soil processes on heathland due to changes in vegetation to oak and Sitka spruce Type de document : texte imprimé Auteurs : Knud Erik Nielsen, Auteur ; Ulla LLadekarl, Auteur ; Per Nørnberg, Auteur Année de publication : 1999 Article en page(s) : pp. 107-116 Langues : Anglais (eng) Catégories : [Thèmes] Pédologie (sol) [Thèmes] Relation sol - végétation Mots-clés : changement de végétation  acidification du sol  forêt de chênes  épicéa de Sitka  lysimètre Résumé : "Soil and soil water chemistry under three different vegetation-types on a former heath area were investigated in Jutland, Denmark. An unmanaged heathland left undisturbed since the start of this century is now invaded by the oaks. Together with a small Sitka plantation (age 60 years), soil development due to vegetation changes was investigated. The typical heathland podzol soil had changed within decades under the oak trees towards an acid brown soil. The soil under the Sitka spruce had changed towards a more strongly podzolized soil compared to the former heath soil. Present processes occurring within the soil were investigated by analysis of soil solution chemistry. The leaching of inorganic ions and soluble organic matter had increased manifold under Sitka spruce. Nitrification increased markedly with soil depth probably due to effects of higher pH. The increase of nitrate with soil depth was followed by a similar increase in dissolved aluminium. The equivalence of the dissolved organic carbon varies under oak and heath between 6 and 10 m eqv g−1 TOC and under Sitka the equivalence of the dissolved carbon was between 10 and 15 m eqv g−1. No nitrate and only traces of ammonium were found in soil water from the upper 30 cm of the soil under heath. Soil nitrogen was almost exclusively (more than 90%) connected to the carbon cycle. Under Sitka spruce generally less than 20% of soil water nitrogen was coupled to the carbon cycle, i.e. most of the nitrogen in the soil water leaving the rooting zone under Sitka spruce was nitrate. In the oak forest, nitrate only appeared as traces in the soil water in the winter period and in the summer period in relatively higher amounts. Generally, between 80% and 90% of the nitrogen was coupled to the carbon cycle in the winter and in the summer only 50%." (source : auteurs) Type de publication : périodique Référence biblio : Nielsen K., LLadekarl U., Nørnberg P., 1999 - Dynamic soil processes on heathland due to changes in vegetation to oak and Sitka spruce. Forest Ecology and Management, 114 (1) : 107-116. ID PMB : 70406 DOI : 10.1016/S0378-1127(98)00385-5 Permalink : http://www.cbnbrest.fr/catalogue_en_ligne/index.php?lvl=notice_display&id=70406 [article]

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Effects on soils of an oak invasion of a Calluna heath, Denmark, I. Morphology and chemistry / Knud Erik Nielsen in Geoderma, vol. 41, n°1-2 (Année 1987)

Public [article]  inGeoderma > vol. 41, n°1-2 (Année 1987) . - pp. 79-95 Titre : Effects on soils of an oak invasion of a Calluna heath, Denmark, I. Morphology and chemistry Type de document : texte imprimé Auteurs : Knud Erik Nielsen, Auteur ; Kristian Dalsgaard, Auteur ; Per Nørnberg, Auteur Année de publication : 1987 Article en page(s) : pp. 79-95 Langues : Anglais (eng) Catégories : [habitats/milieux] 31 - Landes et fruticées [Espèces (in biblio)] Calluna [Thèmes] Relation sol - végétation Mots-clés : changement de végétation Résumé : "Where oak has been invading Hjerl Hede for the last century, four profiles were described and sampled for analyses in a trench extending into a Calluna stand from a pioneer oak about 70 years old. Three additional profiles were studied, one opposite to the oak, a second in another stand of Calluna and a third in an oak forest. Comparisons were then made of the morphology and chemistry of the profiles to identify early changes associated with the invasion. Principal differences attributed to the oak invasion were a marked reduction in the surface layer of organic matter and its conversion from mor to moder, a slight increase in pH of the uppermost horizons under the oak, slight changes in colours from black to brown in deeper horizons and the blurring of their boundaries. Amounts of iron extractable by pyrophosphate and tetraborate from the B horizons in the trench were smaller under the oak than under the Calluna." (source : auteurs) Type de publication : périodique Référence biblio : Nielsen K., Dalsgaard K., Nørnberg P., 1987 - Effects on soils of an oak invasion of a Calluna heath, Denmark, I. Morphology and chemistry. Geoderma, 41 : 79-95. ID PMB : 70409 Permalink : http://www.cbnbrest.fr/catalogue_en_ligne/index.php?lvl=notice_display&id=70409 [article]

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Effects on soils of an oak invasion of a Calluna heath, Denmark, II. Changes in organic matter and cellulose decomposition / Knud Erik Nielsen in Geoderma, vol. 41, n°1-2 (Année 1987)

Public [article]  inGeoderma > vol. 41, n°1-2 (Année 1987) . - pp. 97-106 Titre : Effects on soils of an oak invasion of a Calluna heath, Denmark, II. Changes in organic matter and cellulose decomposition Type de document : texte imprimé Auteurs : Knud Erik Nielsen, Auteur ; Kristian Dalsgaard, Auteur ; Per Nørnberg, Auteur Année de publication : 1987 Article en page(s) : pp. 97-106 Langues : Anglais (eng) Catégories : [ZG] Danemark [habitats/milieux] 31 - Landes et fruticées [Thèmes] Relation sol - végétation Mots-clés : changement de végétation Résumé : "The investigation had two parts. In the first, organic matter was extracted from samples of the O through Bh horizons of seven profiles and then split into humic and fulvic acids. Part of the fulvic acid was treated with polyvinyl-pyrrolidone. In the other part, strips of cotton cloth were placed into the soils for two months, removed and tested for tensile strength to measure their decomposition. The amounts of humic and fulvic acids were both greater under Calluna than under the oaks. Profile distribution was also sharply contrasted under Calluna, being very low in the O horizons and high in the B horizons. Distribution was virtually uniform under the oak. The adsorption of fulvic acids by polyvinyl-pyrrolidone and the decomposition of the cotton strips indicated greater biological activity under the oaks than in the heath. These several differences are attributed to the replacement of one type of vegetation by another." (source : auteurs) Type de publication : périodique Référence biblio : Nielsen K., Dalsgaard K., Nørnberg P., 1987 - Effects on soils of an oak invasion of a Calluna heath, Denmark, II. Changes in organic matter and cellulose decomposition. Geoderma, 41 : 97-106. ID PMB : 70408 Permalink : http://www.cbnbrest.fr/catalogue_en_ligne/index.php?lvl=notice_display&id=70408 [article]

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• Effects on soils of an oak invasion of a Calluna heath, Denmark, I. Morphology and chemistry / Knud Erik Nielsen in Geoderma, vol. 41, n°1-2 (Année 1987)

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