Detrital Input and Removal Treatments (DIRT) from the Andrews Experimental Forest, 1999-2011: soil solution chemistry

<section><para>The DIRT plots on the HJ Andrews Experimental forest follow a controlled sampling design implemented across the DIRT network; specifically, inputs of detritus both above and belowground are manipulated through regular removals and redistribution. The data contained herein express the nutrient (specifically C and N in various forms) concentrations and enzyme activities associated with these treatments during re-measurements in 1999 (and for the enzymes, 2006 and 2010). C and N concentrations in soil, efflux, and soil moisture are measured from bulk samples, respiration chambers, and lysimetry, respectively, and assessed at Oregon State University. Data collection and analyses of these data are ongoing, and often compared with data from other DIRT sites, specifically Boussin forest in Hungary and Harvard Forest in MA. HJ Andrews represents a mixed, old-growth coniferous forest with PSME and TSHE overstory. Measured parameters include DOC (mg/L), SOC (mg C / g soil), CO2 efflux (ml / m2) , and enzyme activity (m mol / g h).</para></section>