<?xml version="1.0" encoding="UTF-8"?><xml><records><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Jung, K.</style></author><author><style face="normal" font="default" size="100%">Chang, S. X.</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Four years of simulated N and S depositions did not cause N saturation in a mixedwood boreal forest ecosystem in the oil sands region in northern Alberta Canada</style></title></titles><keywords><keyword><style  face="normal" font="default" size="100%">field</style></keyword><keyword><style  face="normal" font="default" size="100%">microbiology</style></keyword><keyword><style  face="normal" font="default" size="100%">nitrogen</style></keyword><keyword><style  face="normal" font="default" size="100%">NOx</style></keyword><keyword><style  face="normal" font="default" size="100%">soil properties</style></keyword><keyword><style  face="normal" font="default" size="100%">sulphur and SO2</style></keyword><keyword><style  face="normal" font="default" size="100%">trees</style></keyword><keyword><style  face="normal" font="default" size="100%">UofA</style></keyword><keyword><style  face="normal" font="default" size="100%">vegetation characteristics</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2012</style></year></dates><urls><web-urls><url><style face="normal" font="default" size="100%">https://www.researchgate.net/publication/257197867</style></url></web-urls></urls><publisher><style face="normal" font="default" size="100%">Forest Ecology and Management </style></publisher><volume><style face="normal" font="default" size="100%">280 </style></volume><pages><style face="normal" font="default" size="100%">8 pages </style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">We conducted a simulated nitrogen (N) and sulfur (S) deposition experiment in the Athabasca oil sands region (AOSR) where NOx and SO2 have been emitted from oil sands mining/extracting and upgrading activities and then deposited to the surrounding ecosystems for decades. To evaluate changes in tree growth rates, N pool sizes, and nutrient losses by S and N deposition, the following four treatments were applied: control (CK), N addition (+N, 30 kg N ha−1 yr−1), S addition (+S, 30 kg S ha−1 yr−1), and +NS additions (+NS, 30 kg N and 30 kg S ha−1), from 2006 through 2009. Nitrogen addition increased (p &lt; 0.05) tree growth in the +N and +NS treatments, indicating N-limitation in the studied forest, while none of the treatments affected understory growth or soil microbial biomass. The treatments affected inorganic N concentrations in the soil only immediately following N addition. Minimal amounts of NO3- were leached below 45 cm (considered to be below the main rooting zone) of the soil profile in any of the treatments. Decreases in exchangeable Ca2+ and Mg2+ by N and S additions were likely due to increased tree uptake following increased tree growth in the former and increased leaching with sulfate in the latter. Although the lack of significant N leaching indicates that the risk of N saturation was low after 4 yr of elevated N deposition, reduction of exchangeable base cations implies that nutrient imbalance remains a concern in AOSR in the long term. 

</style></abstract><custom2><style face="normal" font="default" size="100%">Athabasca Oil Sands Region (AOSR)</style></custom2><custom3><style face="normal" font="default" size="100%">http://www.worldcat.org/oclc/5901820637</style></custom3><custom4><style face="normal" font="default" size="100%">OSEMB</style></custom4></record></records></xml>