Home Itens selecionados Provedores de dados OAI Créditos Sobre Ajuda

			Busca avançada
	Provedor de dados 73 (4) Autor Boeckx,Pascal (4) Cleemput,Oswald van (2) Godoy,Roberto (2) Oyarzún,Carlos (2) Paulino,Leandro (1) Peters,Jan (1) Samson,Roeland (1) Verhoest,Niko (1) Vervaet,Hilde (1) Wieme,Vanessa (1) Mais... Palavra-chave Acidification (1) Atmospheric deposition (1) Central and southern Chile (1) Cycling (1) Decision support systems (1) Drinking water (1) Ecohydrology (1) Emission (1) Eutrophication (1) Forest soil (1) Greenhouse effect (1) Hydrology (1) Mineral N (1) Modelling (1) Nitric oxide (1) Nitrogen (1) Nitrogen loss (1) Nitrous oxide (1) Organic N (1) Ozone (1) Mais... Tipo do documento Journal article (4) Ano 2005 (3) 2003 (1) País Chile (4) Idioma Inglês (4)		Ordenar por:  Relevância Autor Título Ano Registros recuperados: 4 Primeira ... 1 ... Última ALTERATION OF NITROGEN CYCLING BY AGRICULTURAL ACTIVITIES, AND ITS ENVIRONMENTAL AND HEALTH CONSEQUENCES 73 Cleemput,Oswald van; Boeckx,Pascal. The food demands of the increasing world population puts pressure on land use and N availability. In this paper an overview is given of the different N cycling processes affected by agricultural activities. Of the amount of N added to the soil, about half is removed from the field as harvested crop, while the remainder of the N is incorporated into soil organic matter or is lost to other parts of the environment. During the last decades there has been much research on environmental consequences of agricultural activities, mainly on emission of gaseous N compounds (NH3, NO, N2O and N2), but also on N leaching, runoff and erosion. Study of the factors controlling loss of N is complex because of their multiplicity and mutual interactions. More recently... Tipo: Journal article Palavras-chave: Acidification; Drinking water; Eutrophication; Greenhouse effect; Nitrogen loss; Ozone. Ano: 2005 URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-66432005000200005 ATMOSPHERIC N DEPOSITION IN CENTRAL AND SOUTHERN CHILE: AN OVERVIEW 73 Godoy,Roberto; Paulino,Leandro; Oyarzún,Carlos; Boeckx,Pascal. Temperate forests in Chile are not yet affected by elevated nitrogen (N) deposition. However, anthropogenic activities such as transport, industry and agriculture have been increasing in central and southern Chile. These activities can substantially alter the atmospheric N load and subsequently N deposition. Nitrogen deposition data for central and southern Chile are scares and scattered. In order to assess trends of N deposition a good knowledge of past and current N depositions is however essential. This study presents an overview of the existing N deposition data in Chile. In central Chile, dry deposition has been estimated at 0.8 kg NO3--N ha-1 yr-1 and 1.0 kg NH4+-N ha-1 yr-1, giving a total of 1.8 kg N ha-1 yr-1 and wet deposition was 0.4 kg NO3--N... Tipo: Journal article Palavras-chave: Atmospheric deposition; Central and southern Chile; Mineral N; Organic N. Ano: 2003 URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-66432003000100008 NO AND N2O FLUXES FROM A BELGIAN FOREST AFFECTED BY ELEVATED NITROGEN DEPOSITION 73 Boeckx,Pascal; Vervaet,Hilde; Cleemput,Oswald van. Nitrous oxide (N2O) and nitric oxide (NO) are important atmospheric trace gases, and soils (including forest soils) are a substantial source of both gases. In forests subjected to elevated N deposition these emissions are considered as indirect emissions from agricultural N sources (mainly NH3) or combustion (e.g. NOx from traffic). However, knowledge about N2O and NO exchange between forests and the atmosphere is scarce. The aim of this study was to determine N2O and NO emission rates from a deciduous forest in Belgium, receiving a high N-deposition (ca. 40 kg N ha-1 yr-1). In April 2000, the NO emission from the forested location was 17.3 (± 1.2) and 17.05 (± 0.7) ng NO-N m-2 s-1, respectively, for the soil including the organic layer and the mineral... Tipo: Journal article Palavras-chave: Emission; Forest soil; Nitrogen; Cycling; Nitric oxide; Nitrous oxide. Ano: 2005 URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-66432005000200003 POSSIBILITIES FOR ECOHYDROLOGICAL MONITORING IN NATURAL AND MANAGED ECOSYSTEMS IN SOUTHERN CHILE 73 Peters,Jan; Wieme,Vanessa; Boeckx,Pascal; Samson,Roeland; Godoy,Roberto; Oyarzún,Carlos; Verhoest,Niko. Ecohydrology investigates how hydrological processes affect plant growth and vice versa. As these mutual interactions are important in many ecosystems, ecohydrology has wide applicability. An important aspect of ecohydrological research is the assessment and prediction of the occurrence of plant species or vegetation types in relation to hydrological or hydrogeochemical habitat conditions. Several models have been developed (e.g. DEMNAT, ICHORS, ITORS, ITORS-VL). All of these models are data driven. Consequently a monitoring network has to be installed, possibly in addition to existing databases. These networks are ecosystem specific but the most widely monitored variables are: water table depth, electric conductivity of groundwater, soil moisture content... Tipo: Journal article Palavras-chave: Ecohydrology; Modelling; Vegetation; Hydrology; Decision support systems. Ano: 2005 URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-66432005000200007 Registros recuperados: 4 Primeira ... 1 ... Última

Empresa Brasileira de Pesquisa Agropecuária - Embrapa Todos os direitos reservados, conforme Lei n° 9.610 Política de Privacidade Área restrita		Embrapa Parque Estação Biológica - PqEB s/n° Brasília, DF - Brasil - CEP 70770-901 Fone: (61) 3448-4433 - Fax: (61) 3448-4890 / 3448-4891 SAC: https://www.embrapa.br/fale-conosco