SciELO - Scientific Electronic Library Online

 
vol.35 issue1Quantification of biomass and energetic value of young natural regenerated stands of Quercus ilex under Mediterranean conditionsCombining taper and basic wood density equations for estimating stem biomass of the Populus x canadensis I - 488 variety author indexsubject indexarticles search
Home Pagealphabetic serial listing  

Services on Demand

Journal

Article

Indicators

Related links

  • On index processCited by Google
  • Have no similar articlesSimilars in SciELO
  • On index processSimilars in Google

Share


Bosque (Valdivia)

On-line version ISSN 0717-9200

Abstract

CUEVAS, Jaime G et al. Nutrient retention in a microcatchment with low levels of anthropogenic pollution. Bosque (Valdivia) [online]. 2014, vol.35, n.1, pp.75-88. ISSN 0717-9200.  http://dx.doi.org/10.4067/S0717-92002014000100008.

Streamside native forests filter nutrients and sediments from extra-riparian environments. Most related studies have been carried out in environments chronically polluted by nutrients, making it difficult to assess whether the detected patterns would hold in less polluted areas, such as Chile. However, there are no studies about Chilean natural streamside vegetation ability to filter nutrients and sediment. We hypothesized that southern Chilean streamside forests efficiently retain nutrients due to their, previously documented, tight nitrogen cycle especially in terms of fixation, mineralization and plant uptake, in addition to the high phosphorus adsorption by volcanic soils and high cation retention due to the expected higher cationic exchange capacity (CEC) in floodplains. We studied a fluvial terrace with grasslands covering the uplands, a forest on a slope, and a floodplain with native trees adjacent to a creek. We laid out nine parallel transects in the aforementioned environments and installed five wells in each transect. We extracted and analyzed groundwater three times a year, finding that the nitrate concentration decreased in the transect from the grassland to the floodplain forest. Ammonium, calcium, potassium, and electrical conductivity increased in the same transect, but these variables were always higher than those in the stream. Moreover, soil chemical determinations showed that ammonium, basic cations, aluminum, aluminum saturation and organic matter increased significantly in the floodplain soil compared to the grassland soil. The CEC was marginally different in the studied transects. We conclude that native forest ecosystems constitute effective filters for the studied nutrients, highlighting the associated soils role.

Keywords : cationic exchange capacity; groundwater; nitrogen cycle; phosphorus adsorption; riparian zones.

        · abstract in Spanish     · text in English     · English ( pdf )