969 Soil Sci. Soc. Am. J. 74:969–978 Published online 17 Mar. 2010 doi:10.2136/sssaj2009.0152 SNRAS Publ. no. 2009-001. Received 22 Apr. 2009. *Corresponding author ([email protected]). © Soil Science Society of America, 5585 Guilford Rd., Madison WI 53711 USA All rights reserved. No part of this periodical may be reproduced or transmitted in any form or by any means, electronic or mechanica...

Wet tropical forests growing on highly weathered soil, depleted in rockderived nutrients, yet rich in nitrogen (N), may respond quite differently to anthropogenic N inputs than those growing on younger soils low in N. We evaluated the effects of firsttime and long-term N additions on the pattern and regulation of hydrologic N losses from wet tropical forests located at the extreme ends of a soi...

Biomass burning produces black carbon (BC), effectively transferring a fraction of the biomass C from an actively cycling pool to a passive C pool, which may be stored in the soil. Yet the timescales and mechanisms for incorporation of BC into the soil profile are not well understood. The High Park fire (HPF), which occurred in northwestern Colorado in the summer of 2012, provided an opportunit...

The soils of the central Oregon pumice plateau are relatively young and infertile, yet support an array of plant diversity and growth in the region’s pine forests. Whether these coarsetextured, pumice and ash soils are resilient to forest disturbance is not well understood. We present results from a long-term experiment that examined changes in soil quality in response to combinations of thinni...

The oxidation of atmospheric CH4 in upland soils is mostly mediated by uncultivated groups of microorganisms that have been identified solely by molecular markers, such as the sequence of the pmoA gene encoding the β-subunit of the particulate methane monooxygenase enzyme. The objective of this work was to compare the activity and diversity of methanotrophs in Amazonian Dark Earth soil (ADE, Ho...

Clearing tropical forests of the Amazon Basin for pasture alters rates of soil nitrogen cycling. Previous studies have shown that rates of soil net N mineralization and net nitri®cation are lower in established pastures than in forests. We compared soil inorganic N concentrations, rates of net and gross mineralization and net and gross nitri®cation in a chronosequence and an experimental slash-...

In acid forest soils nitrate (NO3 ) from anthropogenic nitrogen deposition is retained at levels beyond what can be explained by known biological mechanisms. A number of researchers have hypothesized that abiotic NO3 – incorporation into soil organic matter might be responsible for this phenomenon, however studies have been limited to a few temperate forest sites. The goal of this study was to ...

Soil and foliage samples were collected from 136 sample sites in forested areas of the Dhulikhel Watershed, Nepal. Analyses showed that the soils have small values for pH, base saturation, total nitrogen, carbon and available phosphorus. Sample sites were stratified on the basis of aspect and elevation, soil type, forest type and management and the strata were compared to determine the influenc...

Human population pressures upon land resources have increased the need to assess impacts of land use change on soil quality. In order to assess effects of land use changes on soil quality properties in a tropical forest ecosystem of Bangladesh, soil samples were collected from adjacent well-stocked Shorea robusta natural forest, land reforested with Acacia, grassland and cultivated land. Land u...

Theoretically, fire-tree cover feedbacks can maintain savanna and forest as alternative stable states. However, the global extent of fire-driven discontinuities in tree cover is unknown, especially accounting for seasonality and soils. We use tree cover, climate, fire, and soils data sets to show that tree cover is globally discontinuous. Climate influences tree cover globally but, at intermedi...