TY - JOUR

T1 - Fast accrual of C and N in soil organic matter fractions following post-mining reclamation across the USA

AU - Angst, Gerrit

AU - Mueller, Carsten W.

AU - Angst, Šárka

AU - Pivokonský, Martin

AU - Franklin, Jennifer

AU - Stahl, Peter D.

AU - Frouz, Jan

PY - 2018

Y1 - 2018

N2 - Reclamation of post-mining sites commonly results in rapid accrual of carbon (C) and nitrogen (N) contents due to increasing plant inputs over time. However, little information is available on the distribution of C and N contents with respect to differently stabilized soil organic matter (SOM) fractions during succession or as a result of different reclamation practice. Hence, it remains widely unknown how stable or labile these newly formed C and N pools are. Gaining a deeper understanding of the state of these pools may provide important implications for reclamation practices with respect to C sequestration. We thus investigated C, N, and plant-derived compounds in bulk soil and SOM fractions during succession in post-mining chronosequences (reclaimed with overburden or salvaged topsoil) located along a northwest to southeast transect across the USA. Our results indicate that current reclamation practices perform well with respect to rapid recovery of soil aggregates and the partitioning of C and N to different SOM fractions, these measures being similar to those of natural climax vegetation sites already 2–5 years after reclamation. A general applicability of our results to other post-mining sites with similar reclamation practices may be inferred from the fact that the observed patterns were consistent along the investigated transect, covering different climates and vegetation across the USA. However, regarding SOM stability, the use of salvaged topsoil may be beneficial as compared to that of overburden material because C and N in the fraction regarded as most stable was by 26 and 35% lower at sites restored with overburden as compared to those restored with salvaged topsoil. Plant-derived compounds appeared to be mainly related to bio-available particulate organic matter and particulate organic matter partly stabilized within aggregates, challenging the long-term persistence of plant input C in post-mining soils.

AB - Reclamation of post-mining sites commonly results in rapid accrual of carbon (C) and nitrogen (N) contents due to increasing plant inputs over time. However, little information is available on the distribution of C and N contents with respect to differently stabilized soil organic matter (SOM) fractions during succession or as a result of different reclamation practice. Hence, it remains widely unknown how stable or labile these newly formed C and N pools are. Gaining a deeper understanding of the state of these pools may provide important implications for reclamation practices with respect to C sequestration. We thus investigated C, N, and plant-derived compounds in bulk soil and SOM fractions during succession in post-mining chronosequences (reclaimed with overburden or salvaged topsoil) located along a northwest to southeast transect across the USA. Our results indicate that current reclamation practices perform well with respect to rapid recovery of soil aggregates and the partitioning of C and N to different SOM fractions, these measures being similar to those of natural climax vegetation sites already 2–5 years after reclamation. A general applicability of our results to other post-mining sites with similar reclamation practices may be inferred from the fact that the observed patterns were consistent along the investigated transect, covering different climates and vegetation across the USA. However, regarding SOM stability, the use of salvaged topsoil may be beneficial as compared to that of overburden material because C and N in the fraction regarded as most stable was by 26 and 35% lower at sites restored with overburden as compared to those restored with salvaged topsoil. Plant-derived compounds appeared to be mainly related to bio-available particulate organic matter and particulate organic matter partly stabilized within aggregates, challenging the long-term persistence of plant input C in post-mining soils.

KW - Carbon sequestration

KW - Chronosequence

KW - Overburden

KW - Plant-derived lipids

KW - Stockpiled topsoil

KW - Succession

U2 - 10.1016/j.jenvman.2017.12.050

DO - 10.1016/j.jenvman.2017.12.050

M3 - Journal article

C2 - 29294447

AN - SCOPUS:85039800854

VL - 209

SP - 216

EP - 226

JO - Journal of Environmental Management

JF - Journal of Environmental Management

SN - 0301-4797

ER -