https://www.socictopen.socict.org/files/original/a7892203a407c3809881bfd1fb4901ec.pdf 90e91d04d1a8695f3ec76ef61163d52c Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Title A name given to the resource Agricultura sostenible Description An account of the resource Dominio científico: Agricultura sostenible Text A resource consisting primarily of words for reading. Examples include books, letters, dissertations, poems, newspapers, articles, archives of mailing lists. Note that facsimiles or images of texts are still of the genre Text. Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Title A name given to the resource Relações entre uso do solo, relevo e fertilidade do solo em escala de microbacia Relationships among land use, relief and soil fertility at watershed scale Creator An entity primarily responsible for making the resource Antonio C. dos Santos, Ignacio H. Salcedo, Sandra R. da S. Galvão Description An account of the resource A produtividade em sistemas agrícolas de subsistência depende do nível de fertilidade natural do solo. Em condições de relevo forte ondulado, espera-se que a fertilidade do solo se modifique não apenas pelo tipo de uso mas, também, devido à sua posição no relevo. Para avaliar essas modificações, 260 amostras simples de solo (0-20 cm) da microbacia Vaca Brava, PB, representando combinações de três usos do solo, cinco posições no relevo e cinco classes texturais, foram analisadas quanto aos teores de P disponível, bases e acidez trocáveis. Ca e Mg compreenderam 75-80% dos cátions trocáveis, K e Na, de 10 a 15%, e H+Al, 10%; o valor de pH médio foi 5,5, enquanto P Mehlich-1 foi, em média, 3,8 mg kg-1 solo. Apesar dos efeitos significativos (p < 0,05) de uso, relevo e textura nos teores de alguns nutrientes, de forma geral a bacia pareceu relativamente uniforme. A principal diferença entre os usos decorreu da adição de esterco em áreas de roçado e capineira localizadas, preferencialmente, em áreas de pedimento e várzea. Ao redor de 80% das amostras apresentaram teores baixos de P enquanto 70% mostraram teores médios de K; entretanto, utilizando-se o índice K/(Ca+Mg)0,5 conclui-se que a quase totalidade das amostras se apresentou deficiente em K.Productivity in subsistence agricultural systems relies on natural soil fertility levels. Under strongly undulated relief conditions, it is expected that soil fertility will be determined not only by land use, but also by the position in the landscape. To study these relationships 260 single soil samples (0-20 cm) from the Vaca Brava watershed, Paraiba, representing combinations of three land uses, five positions in the landscape and five textures were analyzed for extractable P, exchangeable bases and soil acidity. Ca and Mg comprised 75-80% of exchangeable cations, K and Na between 10 and 15% and H+Al 10%. The average pH was 5.5, while extractable P (Mehlich-1) averaged 3.8 mg kg-1 soil. Although land use, relief and texture exerted significant effects (p < 0.05) upon certain nutrient concentrations, in a broad sense the watershed appeared relatively uniform. The main effect of land use resulted from the use of animal manure in areas of subsistence agriculture and fodder, which were preferentially located at the base of stopes and low lands positions. Approximately 80% of the samples were low in extractable P, while 70% had medium levels of extractable K. However, when available K was estimated by the K/(Ca+Mg)0,5 ratio, most samples were classified as low. Date A point or period of time associated with an event in the lifecycle of the resource 2008 Subject The topic of the resource Phosphorus, Potassium, agricultura de subsistencia, capineiras, fodder, fósforo, pastagens, pasture, potássio, subsistence agriculture Identifier An unambiguous reference to the resource within a given context 10.1590/S1415-43662008000500003 Source A related resource from which the described resource is derived Revista Brasileira de Engenharia Agrícola e Ambiental - Agriambi Publisher An entity responsible for making the resource available Universidade Federal de Campina Grande Coverage The spatial or temporal topic of the resource, the spatial applicability of the resource, or the jurisdiction under which the resource is relevant Agriculture (General) Relation A related resource <a href="http://www.scielo.br/scielo.php?script=sci_arttext&amp;pid=S1415-43662008000500003" target="_blank" rel="noreferrer noopener">http://www.scielo.br/scielo.php?script=sci_arttext&amp;pid=S1415-43662008000500003</a>