Heavy and light fraction organic matter across landscapes and soil profiles

Here we provide percent contribution of mineral associated (i.e., heavy fraction - HF) and relatively more labile (i.e., light fraction - LF) organic matter through soil profiles and along hillslope catena within sites in the Critical Zone Network (CZNet) Geomicrobiology cluster. Each sample is separated into a HF an a LF utilizing a 1.85 g cm-3 sodium polytungstate (3Na2WO4·9WO3·H2O or Na6 [H2W12O40]) solution. The resultant fractions are run for percent carbon (C) and nitrogen (N) and their associated stable isotopes (δ13C and δ15N) to offer novel insights in soil organic matter processes. Samples that were either too small for analytical analysis or below instrument detection limit are labeled with BDL.

本数据集提供了关键带观测网络（Critical Zone Network，CZNet）地质微生物学集群各研究点位内，贯穿土壤剖面并沿山坡坡链分布的矿物结合态有机质（即重组分，heavy fraction，HF）与相对更易降解的活性有机质（即轻组分，light fraction，LF）的百分占比。所有样品均采用1.85 g·cm⁻³的多钨酸钠（3Na₂WO₄·9WO₃·H₂O 或 Na₆[H₂W₁₂O₄₀]）溶液分离为重组分与轻组分。随后对所得组分测定碳（C）、氮（N）的百分含量及其对应的稳定同位素（δ¹³C与δ¹⁵N），以期为土壤有机质转化过程研究提供全新认知。因样品量不足无法开展分析测试，或目标物含量低于仪器检测限的样品，均标记为BDL。