1775 Carbon (C) and nitrogen (N) play an important role in the restoration of ecosystem functions of reclaimed mine soils (RMSs). Postreclamation land use in RMSs affects soil C and N pools and fluxes. We compared the effects of 28-yr-old postreclamation land uses (forest, hay, and pasture) on selected chemical properties of soil, and C and N pools in reference to undisturbed forest and moderately disturbed agricultural land use in southeastern Ohio. e electrical conductivity was higher in RMSs under hay than that in pasture and forest land uses. e RMSs under pasture, hay, and forest had moderately acidic, neutral to slightly alkaline, and slightly alkaline pH, respectively. In the 0- to 5-cm soil depth, soil organic C (SOC) was higher in RMSs under pasture by 99% and under hay by 52% over that under forest. Similarly, total nitrogen (TN) was higher in RMSs under pasture by 98% and under hay by 43% over that under forest. Aggregate-associated SOC concentration in the 0- to 5-cm depth decreased in the order of RMSs under hay > RMSs under pasture > RMSs under forest. e SOC pools in the 0- to 30-cm depth decreased in the order of RMSs under hay = RMSs under pasture > RMSs under forest = undisturbed forest = agriculture land use. Nitrogen pools followed a similar trend. Hay land use has a better potential for improving soil quality in RMSs by enhancing chemical properties and SOC and TN pools than forest or pasture land uses. Soil Carbon and Nitrogen in 28-Year-Old Land Uses in Reclaimed Coal Mine Soils of Ohio Raj K. Shrestha* and Rattan Lal The Ohio State University R esearch on soil quality assessment has been primarily focused on agricultural and forest soils. ere is a strong need to monitor changes in the soil quality of reclaimed mine soils (RMSs). Mining causes drastic disturbances in soil properties. Restoration of soil quality and ecosystem function of RMSs depends on the reclamation methods and re-establishment of vegetation, which can enhance and sustain plant growth (Shrestha and Lal, 2006). Successful establishment of a vegetative cover on RMSs depends on understanding the chemical and physical properties of disturbed soils. e RMSs are pedogenically young soils, and their properties are strongly influenced by the parent material, mining procedure, reclamation method, and postreclamation land uses. Some adverse physicochemical properties of RMSs may inhibit soil-forming processes and adversely affect plant growth. ese soils usually contain low concentrations of soil organic carbon (SOC), nitrogen (N), and phosphorus (P); high bulk density (BD) and rock fragments; unfavorable soil pH; poor structure; low po- rosity and water-holding capacity; and low biomass productivity (Indorante et al., 1981; Boerner et al., 1998; Hearing et al., 2000; Burger, 2004). Growth-limiting acidity in the surface-mined soils is caused by deposition of low-base-content overburden consisting primarily of sandstone or shale parent material and sulfur-bearing (FeS 2 ) overburden layers (Mays et al., 2000). Acidic conditions limit root growth and establishment of plants. Applying fertil- izers and using lime to raise soil pH above 5.5 can enhance plant growth. A yearly rate of 140 to 170 kg ha −1 actual N, split applied, can provide economical yield increases with tall grasses for ade- quate plant growth and ecosystem function in RMSs (Underwood et al., 2006). Plant-available P may also be low in mine soils due to high P fixation capacity of the spoil (Roberts et al., 1988). Disturbance during mining results in loss of SOC and N pools. us, reclamation of mined soils is associated with an increase in SOC and N concentrations and improvement in soil fertility. Factors that affect SOC and N concentrations and pools include biomass inputs, roots, mycorrhizal fungi, degree of physical distur- bances, introduction of plants and animal species, atmospheric de- position of materials, and effects on soil decomposers and primary producers (Pouyat and McDonnell, 1991; Carreiro et al., 1999). ere are about 3.2 Mha of RMSs in the USA and 0.04 Mha in Ohio, which have the potential of sequestering C in the terrestrial ecosystem by as much as 8.19 Tg yr −1 under forest land use (Shrestha et al., 2007; OSM, 2003). Predominant postreclamation land uses in Abbreviations: BD, bulk density; EC, electrical conductivity; RMS, reclaimed mine soil; SIC, soil inorganic carbon; SOC, soil organic carbon; TC, total carbon; TN, total nitrogen. School of Environment and Natural Resources, The Ohio State Univ., 2021 Coffey Road, Columbus, Ohio 43210. Copyright © 2007 by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America. All rights reserved. No part of this periodical may be reproduced or transmitted in any form or by any means, electronic or mechanical, including pho- tocopying, recording, or any information storage and retrieval system, without permission in writing from the publisher. Published in J. Environ. Qual. 36:1775–1783 (2007). doi:10.2134/jeq2007.0071 Received 7 Feb. 2007. *Corresponding author (Shrestha.10@osu.edu). © ASA, CSSA, SSSA 677 S. Segoe Rd., Madison, WI 53711 USA TECHNICAL REPORTS: ECOSYSTEM RESTORATION