caa a22 4500 605517762 CHVBK 20210128100721.0 cr unu---uuuuu 210128e20150901xx s 000 0 eng 10.1007/s10533-015-0121-4 doi (NATIONALLICENCE)springer-10.1007/s10533-015-0121-4 Soil organic matter regulates molybdenum storage and mobility in forests [Elektronische Daten] [Jade Marks, Steven Perakis, Elizabeth King, Julie Pett-Ridge] The trace element molybdenum (Mo) is essential to a suite of nitrogen (N) cycling processes in ecosystems, but there is limited information on its distribution within soils and relationship to plant and bedrock pools. We examined soil, bedrock, and plant Mo variation across 24 forests spanning wide soil pH gradients on both basaltic and sedimentary lithologies in the Oregon Coast Range. We found that the oxidizable organic fraction of surface mineral soil accounted for an average of 33% of bulk soil Mo across all sites, followed by 1.4% associated with reducible Fe, Al, and Mn-oxides, and 1.4% in exchangeable ion form. Exchangeable Mo was greatest at low pH, and its positive correlation with soil carbon (C) suggests organic matter as the source of readily exchangeable Mo. Molybdenum accumulation integrated over soil profiles to 1m depth (τMoNb) increased with soil C, indicating that soil organic matter regulates long-term Mo retention and loss from soil. Foliar Mo concentrations displayed no relationship with bulk soil Mo, and were not correlated with organic horizon Mo or soil extractable Mo, suggesting active plant regulation of Mo uptake and/or poor fidelity of extractable pools to bioavailability. We estimate from precipitation sampling that atmospheric deposition supplies, on average, over 10 times more Mo annually than does litterfall to soil. In contrast, bedrock lithology had negligible effects on foliar and soil Mo concentrations and on Mo distribution among soil fractions. We conclude that atmospheric inputs may be a significant source of Mo to forest ecosystems, and that strong Mo retention by soil organic matter limits ecosystem Mo loss via dissolution and leaching pathways. Springer International Publishing Switzerland, 2015 Soil organic matter nationallicence Molybdenum nationallicence Oregon coast range nationallicence Nitrogen fixation nationallicence Marks Jade Department. Crop & Soil Science, Oregon State University, 97331, Corvallis, OR, USA aut Perakis Steven US Geological Survey, Forest and Range Ecosystem Science Center, 3200 SW Jefferson Way, 97331, Corvallis, OR, USA aut King Elizabeth College of Earth, Ocean, and Atmospheric Sciences, Oregon State University, 97331, Corvallis, OR, USA aut Pett-Ridge Julie Department. Crop & Soil Science, Oregon State University, 97331, Corvallis, OR, USA aut Biogeochemistry Springer International Publishing 125/2(2015-09-01), 167-183 0168-2563 125:2<167 2015 125 10533 https://doi.org/10.1007/s10533-015-0121-4 text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s10533-015-0121-4 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Marks Jade Department. Crop & Soil Science, Oregon State University, 97331, Corvallis, OR, USA aut NATIONALLICENCE 700 1- Perakis Steven US Geological Survey, Forest and Range Ecosystem Science Center, 3200 SW Jefferson Way, 97331, Corvallis, OR, USA aut NATIONALLICENCE 700 1- King Elizabeth College of Earth, Ocean, and Atmospheric Sciences, Oregon State University, 97331, Corvallis, OR, USA aut NATIONALLICENCE 700 1- Pett-Ridge Julie Department. Crop & Soil Science, Oregon State University, 97331, Corvallis, OR, USA aut NATIONALLICENCE 773 0- Biogeochemistry Springer International Publishing 125/2(2015-09-01), 167-183 0168-2563 125:2<167 2015 125 10533