Dye tracer and morphophysical properties to observe water flow in a Gleyic Luvisol

Abstract

The understanding of the preferential water flow and solute transport is important with regard to losses of nutrients and pesticides that affect the quality of the groundwater or surface water resources. Experiments using the brilliant blue dye tracer, a tension infiltrometer (TI) and a double square infiltrometer (DI) were carried out in the experimental field site located around 15 km southeast of the city of Rostock (North-Eastern Germany) on arable land in a Pleistocene lowland landscape where corn (Zea mays L.) and barley (Hordeum spp.) had been cultivated. One day after dye the infiltration, a pit was dug and vertical profiles were prepared in the TI and DI sites to assess the dye pathways in the subsoil of a Gleyic Luvisol. We wanted to examine if the mottled red and white (bleached) colour-pattern of the Gleyic Luvisol subsoil resulting from temporally stagnant water could be related to flow paths as visualized by dye tracing and if the soil colour could be related to other physical soil properties. Biogenic soil structures were the main transport routes conducting water and solutes into great depth in short time. These pathways had lower bulk density and less cone resistance than the adjacent red or white (bleached) areas of the Gleyic Luvisol subsoil. The red areas were involved in transport because their water contents increased after as compared to before infiltration. However, the measured physical soil properties did not differ between white and red areas. We assume that red areas participate in transport at least by imbibing water from the adjacent biogenic flow paths. Key words: soil water content, bulk density, cone resistance Fluxo de água em um Gleyic Luvisol usando traçador e sua relação com as propriedades físicas e morfológicas do solo RESUMO: O fluxo preferencial de água e o transporte de solutos relacionam-se com perdas de nutrientes e pesticidas e afetam a qualidade de águas subterrâneas. Foram realizados experimentos utilizando o traçador Brilhante Blue, um infiltrômetro de tensão (TI) e um infiltrômetro com "duplos quadrados" (DI) num campo experimental localizado a cerca de 15 km a sudeste da cidade de Rostock (nordeste da Alemanha) num solo onde cultiva-se milho (Zea mays L.) e cevada (Hordeum spp.). Um dia após a infiltração do traçador, perfis de solo foram escavados no local do TI e do DI para observar o fluxo da água deixado pelo do traçador no solo. O objetivo era verificar se os mosqueados vermelhos e partes esbranquiçadas cor-padrão do subsolo do Gleyic Luvisol, resultante da água estagnada temporariamente, poderia estar relacionada ao fluxo da água visualizados pelo traçador e se a cor do solo poderia estar relacionada a outras propriedades físicas do solo. A estrutura biogênica do solo foi a principal rota de transporte conduzindo água e solutos em profundidade e em menor tempo. Esses caminhos tiveram menor densidade do solo e menor resistência do que as áreas vermelhas e esbranquiçadas adjacentes do subsolo do Gleyic Luvisol. Áreas vermelhas foram relacionadas com...

Main water pathways in cultivated clayey calcisols in molassic hills in southwestern France: Toward spatialization of soil waterlogging

“…In soils with poor internal drainage and no topographic gradient, such as Luvisols, water infiltrates vertically until it encounters an impermeable layer, creating a perched water table and waterlogging. This phenomenon has been widely documented, particularly in the context of pipe drainage networks, in the Netherlands (Bouma, 1981; van Lanen et al., 1992), in the alluvial terraces of the Garonne River in southwestern France (Bernot, 1961; Bouzigues & Vinas, 1989; Bouzigues et al., 1998; Concaret, 1981; Favrot et al., 1992; Guiresse & Bourgeat, 1991; Michel & Tessier, 2003; Tessier et al., 1992; Zimmer et al., 1991) or in Germany (Salvador et al., 2011; Hartmann et al., 2012). Waterlogging also occurs downslope of watercourses due to rising groundwater levels, which can cause more or less permanent waterlogging depending on groundwater fluctuations (Legros, 2007).…”