caa a22 4500 605517088 CHVBK 20210128100717.0 cr unu---uuuuu 210128e20150301xx s 000 0 eng 10.1007/s10533-014-0064-1 doi (NATIONALLICENCE)springer-10.1007/s10533-014-0064-1 Seasonal changes in soil organic matter after a decade of nutrient addition in a lowland tropical forest [Elektronische Daten] [Benjamin Turner, Joseph Yavitt, Kyle Harms, Milton Garcia, S. Wright] Soil organic matter is an important pool of carbon and nutrients in tropical forests. The majority of this pool is assumed to be relatively stable and to turn over slowly over decades to centuries, although changes in nutrient status can influence soil organic matter on shorter timescales. We measured carbon, nitrogen, and phosphorus concentrations in soil organic matter and leaf litter over an annual cycle in a long-term nutrient addition experiment in lowland tropical rain forest in the Republic of Panama. Total soil carbon was not affected by a decade of factorial combinations of nitrogen, phosphorus, or potassium. Nitrogen addition increased leaf litter nitrogen concentration by 7% but did not affect total soil nitrogen. Phosphorus addition doubled the leaf litter phosphorus concentration and increased soil organic phosphorus by 50%. Surprisingly, concentrations of carbon, nitrogen, and phosphorus in soil organic matter declined markedly during the four-month dry season, and then recovered rapidly during the following wet season. Between the end of the wet season and the late dry season, total soil carbon declined by 16%, total nitrogen by 9%, and organic phosphorus by between 19% in control plots and 25% in phosphorus addition plots. The decline in carbon and nitrogen was too great to be explained by changes in litter fall, bulk density, or the soil microbial biomass. However, a major proportion of the dry-season decline in soil organic phosphorus was explained by a corresponding decline in the soil microbial biomass. These results have important implications for our understanding of the stability and turnover of organic matter in tropical forest soils, because they demonstrate that a considerable fraction of the soil organic matter is seasonally transient, despite the overall pool being relatively insensitive to long-term changes in nutrient status. US Government, 2015 Carbon nationallicence Gigante Peninsula nationallicence Nitrogen nationallicence Panama nationallicence Phosphorus nationallicence Soil microbial biomass nationallicence Turner Benjamin Smithsonian Tropical Research Institute, Balboa, Apartado 0843-03092, Ancon, Republic of Panama aut Yavitt Joseph Department of Natural Resources, Cornell University, 14853, Ithaca, NY, USA aut Harms Kyle Department of Biological Sciences, Louisiana State University, 70803, Baton Rouge, LA, USA aut Garcia Milton Smithsonian Tropical Research Institute, Balboa, Apartado 0843-03092, Ancon, Republic of Panama aut Wright S. Smithsonian Tropical Research Institute, Balboa, Apartado 0843-03092, Ancon, Republic of Panama aut Biogeochemistry Springer International Publishing 123/1-2(2015-03-01), 221-235 0168-2563 123:1-2<221 2015 123 10533 https://doi.org/10.1007/s10533-014-0064-1 text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s10533-014-0064-1 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Turner Benjamin Smithsonian Tropical Research Institute, Balboa, Apartado 0843-03092, Ancon, Republic of Panama aut NATIONALLICENCE 700 1- Yavitt Joseph Department of Natural Resources, Cornell University, 14853, Ithaca, NY, USA aut NATIONALLICENCE 700 1- Harms Kyle Department of Biological Sciences, Louisiana State University, 70803, Baton Rouge, LA, USA aut NATIONALLICENCE 700 1- Garcia Milton Smithsonian Tropical Research Institute, Balboa, Apartado 0843-03092, Ancon, Republic of Panama aut NATIONALLICENCE 700 1- Wright S. Smithsonian Tropical Research Institute, Balboa, Apartado 0843-03092, Ancon, Republic of Panama aut NATIONALLICENCE 773 0- Biogeochemistry Springer International Publishing 123/1-2(2015-03-01), 221-235 0168-2563 123:1-2<221 2015 123 10533