Characteristics of dissolved organic matter in forest soils: influence of different plant covering

To investigate the influence of different plant covering on dissolved organic matter (DOM) in forest soils, the DOM characteristics of soil sample in P. massoniana plantation forest and mixed conifer-broadleaf forest of P. massoniana and C. carlesii were researched by using chemical and spectroscopic methods, including total organic carbon (TOC), total nitrogen (TN), C/N ratios, dissolved organic carbon (DOC) and dissolved organic nitrogen (DON), together with aromaticity index (AIX) and humification index (HIX). Results showed that TOC, TN and C/N ratios were much higher in soils of PC than P, together with the level of DOC and DON, and the spectroscopic characteristics of DOM including AIX and HIX. It's suggested that different plant covering in forest have great influences on soil DOM characteristics. DOM concentrations in mixed forest of P. massoniana and C. carlesii were much higher than pure conifer forest of C. carlesii. Thus, mixed conifer-broadleaf forest was more suitable choice for ecological restoration and reconstruction in southeast China.