TY - JOUR

T1 - Effects of land-use change on chemical composition of soil organic matter in tropical lowland Bolivia

AU - Abe, Susumu S.

AU - Mueller, Carsten W.

AU - Steffens, Markus

AU - Koelbl, Angelika

AU - Knicker, Heike

AU - Koege-Knabner, Ingrid

PY - 2009/8/24

Y1 - 2009/8/24

N2 - Land-use change affects not only the amount of soil organic matter (SOM) but also its composition. We performed cross-polarization magic angle spinning (CPMAS) 13C and 15N nuclear magnetic resonance (NMR) spectroscopy to investigate the chemical composition of bulk SOM in topsoils (0-15 cm) under different land use, namely native forest (NF), 27-year cropland with wheat/soybean rotation (CL) and 27-year rangelands with guineagrass (RG) and with bahiagrass (RB), in south-east Bolivia. The findings of this study showed only a subtle alteration of composition of bulk SOM despite the large changes in carbon (C) content. Nevertheless, NF and RB showed a slightly lower abundance of aromatic C but a higher proportion of alkyl C compared to CL and RG where the loss of organic matter was substantial. This suggests that relatively stable components dominated by aromatic structures had relatively enriched during SOM decomposition under agricultural practices. A slight disparity of SOM composition observed between RG and RB (less O-alkyl C but more aromatic C in RG than RB) suggests that grass species influenced SOM quality even under the same land use, namely the rangeland. On the other hand, organic N composition was less affected by land use or management practice than C forms. Journal Compilation

AB - Land-use change affects not only the amount of soil organic matter (SOM) but also its composition. We performed cross-polarization magic angle spinning (CPMAS) 13C and 15N nuclear magnetic resonance (NMR) spectroscopy to investigate the chemical composition of bulk SOM in topsoils (0-15 cm) under different land use, namely native forest (NF), 27-year cropland with wheat/soybean rotation (CL) and 27-year rangelands with guineagrass (RG) and with bahiagrass (RB), in south-east Bolivia. The findings of this study showed only a subtle alteration of composition of bulk SOM despite the large changes in carbon (C) content. Nevertheless, NF and RB showed a slightly lower abundance of aromatic C but a higher proportion of alkyl C compared to CL and RG where the loss of organic matter was substantial. This suggests that relatively stable components dominated by aromatic structures had relatively enriched during SOM decomposition under agricultural practices. A slight disparity of SOM composition observed between RG and RB (less O-alkyl C but more aromatic C in RG than RB) suggests that grass species influenced SOM quality even under the same land use, namely the rangeland. On the other hand, organic N composition was less affected by land use or management practice than C forms. Journal Compilation

KW - C and N nuclear magnetic resonance analysis

KW - Hydrofluoric acid pretreatment

KW - Land-use change

KW - Soil organic matter quality

UR - http://www.scopus.com/inward/record.url?scp=68949122887&partnerID=8YFLogxK

U2 - 10.1111/j.1744-697X.2009.00146.x

DO - 10.1111/j.1744-697X.2009.00146.x

M3 - Journal article

AN - SCOPUS:68949122887

VL - 55

SP - 104

EP - 109

JO - Grassland Science

JF - Grassland Science

SN - 1744-6961

IS - 2

ER -