A Throughfall Collection Method Using Mixed Bed Ion Exchange Resin Columns

Abstract

Measurement of ionic deposition in throughfall is a widely used method for measuring deposition inputs to the forest floor. Many studies have been published, providing a large database of throughfall deposition inputs to forests. However, throughfall collection and analysis is labor intensive and expensive because of the large number of replicate collectors needed and because sample collection and chemical analyses are required on a stochastic precipitation event-based schedule. Therefore we developed and tested a throughfall collector system using a mixed bed ion exchange resin column. We anticipate that this method will typically require only one to three samplings per year. With this method, bulk deposition and bulk throughfall are collected by a funnel or snow tube and ions are retained as the solution percolates through the resin column. Ions retained by the resin are then extracted in the same column with 2N KCl and analyzed for nitrate and ammonium. Deposition values in throughfall from conventional throughfall solution collectors and colocated ion exchange samplers were not significantly different during consecutive 3- and 4-month exposure periods at a high (Camp Paivika; >35 kg N ha-1 year-1) and a low deposition (Barton Flats; 5–9 kg N ha-1 year-1) site in the San Bernardino Mountains in southern California. N deposition in throughfall under mature pine trees at Camp Paivika after 7 months of exposure was extremely high (87 and 92 kg ha-1 based on the two collector types) compared to Barton Flats (11 and 13 kg ha-1). A large proportion of the N deposited in throughfall at Camp Paivika occurred as fog drip, demonstrating the importance of fog deposition as an input source of N at this site. By comparison, bulk deposition rates in open areas were 5.1 and 5.4 kg ha-1 at Camp Paivika based on the two collector types, and 1.9 and 3.0 kg ha-1 at Barton Flats.

Correcting for background nitrate contamination in KCl-extracted samples during isotopic analysis of oxygen and nitrogen by the denitrifier method

“…[12,13] Pseudomonas aureofaciens was initially used in seawater to study nitrogen cycling in marine ecosystems, [14,15] suggesting that high salt concentrations should not affect the method. Standard reagent grade KCl has a label purity of 99-100.5% KCl.…”

Atmospheric Wet, Dry and Bulk Deposition of Inorganic Nitrogen in the Rio de Janeiro State

“…29 Fenn e colaboradores propuseram modificações no coletor de deposição total pela substituição do frasco coletor por coluna de plástico contendo mistura de resinas de troca iônica (Amberlite IRN 150) para a determinação específica de nitrogênio inorgânico (NH 4 + e NO 3 -). 30 Essa técnica apresenta as seguintes vantagens em relação ao coletor convencional: a) menor frequência de coleta por permitir maior período de exposição; b) maior estabilidade química da espécie de interesse durante a amostragem. 30 …”

“…30 Essa técnica apresenta as seguintes vantagens em relação ao coletor convencional: a) menor frequência de coleta por permitir maior período de exposição; b) maior estabilidade química da espécie de interesse durante a amostragem. 30 …”

Atmospheric Nitrogen Deposition Associated with the Eutrophication of Taihu Lake

“…Many literature studies have shown that the concentration of N deposition in water N loads has increased [8][9][10], and the ecological effects of atmospheric N deposition have received a great deal of attention in recent years [11,12]. Many methods have been employed to collect N deposition, including ion-exchange resin, micrometeorological integral total N input, and minusing methods [13][14][15][16]. Due to the rapid population growth, industrialization, vehicle ownership, and fossil fuel combustion, the NO x emissions in China have shown a marked increase of 2.8 times from 1980 to 2003 [17,18].…”