Monitoring the fluvial palynomorph load in a lowland temperate catchment and its relationship to suspended sediment and discharge

Abstract

Despite it being a component of the seston we know very little about fluvial (waterborne) pollen and spore (palynomorph) transport. This paper presents the results of a monitoring programme conducted over two years and at a catchment scale in South West England. A hierarchical monitoring network was established with flood peak samples taken at 9 sub-catchments, intra-hydrograph samples taken in two sub-catchments and time-integrated sampling undertaken at one location. In addition sampling was undertaken of probable palynomorph sources such as channel bed and bank sediments, and the airborne pollen flux was monitored using modified Tauber traps. The results support previous research in illustrating how the vast majority of fluvial pollen and spores are transported during floods (91%) and that the main control on waterborne palynomorph assemblages is the catchment vegetation and its spatial distribution but with a long-distance (extra-catchment) component. However, strong seasonal effects are also shown, and the importance of distinctive sources such as the riparian input, bed re-suspension and overland flow into drains and tributaries is revealed. Fine sediment in river pools appears to act as a selective store of damaged cereal type pollen grains derived from arable fields. Although pollen does form part of composite particles the data presented here suggest that the majority of the pollen is transported as single grains. Fluvial palynomorph loading is strongly dependant upon discharge and so concentrations in laminated or varved sediments could be regarded as a proxy for flood magnitude.

Investigating the use of fallout and geogenic radionuclides as potential tracing properties to quantify the sources of suspended sediment in a mining catchment in New Caledonia, South Pacific

“…radioactive elements) (Koiter et al 2013). In recent years, these latter have diversified with the emergence of more alternative sediment fingerprinting techniques based on sediment color (Martínez-Carreras et al 2010;Legout et al 2013), pollen plant (Brown et al 2008) or more recently environmental DNA (Ficetola et al 2018;Evrard et al 2019). This diversity in the use of fingerprints has been achieved in conjunction with the improvement of mixing models (e.g.…”

Análisis E Interpretación De Registros Palinológicos De Sucesiones Aluviales De La Región Pampeana: Revisión E Implicancias Para La Reconstrucción De La Vegetación Y El Clima Durante El Pleistoceno Tardio - Holoceno

“…El polen transportado fluvialmente es una importante fuente de palinomorfos contenidos en los depósitos aluviales y los palinólogos han tenido diferentes opiniones sobre el polen aluvial. Por tal motivo, han examinado el polen suspendido en el agua en numerosos ríos y arroyos (e.g., Catto, 1985;Chmura y liu, 1990;Traverse, 1992;smirnov et al, 1996;Xu et al, 1996;Chmura et al, 1999;Brown et al, 2007Brown et al, , 2008 y el incluido en muestras de sedimento superficial (e.g., Grichuk, 1967;solomon et al, 1982;Fall, 1987;Xu et al, 1996;Moss et al, 2005;Rojo et al, 2012) Brown (1985), Catto (1985), Fall (1987) y Xu et al (1996) han argumentado que el transporte fluvial tiende a clasificar hidráulicamente a los granos de polen por tamaño, concentrando preferentemente a unos como componentes de la fracción arena y a otros con la fracción limo-arcilla. Estos hallazgos son consistentes en general con los modelos experimentales de transporte de polen en un canal artificial y, si bien el tamaño es el factor más importante en la clasificación, también están involucradas la forma y/o la densidad de los granos de polen (Brush y Brush, 1972;Holmes, 1990 (Xu et al, 1996).…”

Palinología Del Meso-Cenozoico en Argentina. Volumen en Homenaje a Mirta Elena Quattrocchio

“…El polen transportado fluvialmente es una importante fuente de palinomorfos contenidos en los depósitos aluviales y los palinólogos han tenido diferentes opiniones sobre el polen aluvial. Por tal motivo, han examinado el polen suspendido en el agua en numerosos ríos y arroyos (e.g., Catto, 1985;Chmura y liu, 1990;Traverse, 1992;smirnov et al, 1996;Xu et al, 1996;Chmura et al, 1999;Brown et al, 2007Brown et al, , 2008 y el incluido en muestras de sedimento superficial (e.g., Grichuk, 1967;solomon et al, 1982;Fall, 1987;Xu et al, 1996;Moss et al, 2005;Rojo et al, 2012) (Xu et al, 1996). Este control no ha sido contemplado, aun cuando la variabilidad facial es considerable en esas sucesiones .…”