Premium
Effects of nutrient additions on ecosystem carbon cycle in a Puerto Rican tropical wet forest
Author(s) -
LI YIQING,
XU MING,
ZOU XIAOMING
Publication year - 2006
Publication title -
global change biology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 4.146
H-Index - 255
eISSN - 1365-2486
pISSN - 1354-1013
DOI - 10.1111/j.1365-2486.2005.01096.x
Subject(s) - plant litter , litter , environmental science , nutrient , biomass (ecology) , agronomy , soil carbon , ecosystem , human fertilization , soil water , tropics , carbon sequestration , carbon cycle , soil organic matter , ecology , biology , carbon dioxide , soil science
Wet tropical forests play a critical role in global ecosystem carbon (C) cycle, but C allocation and the response of different C pools to nutrient addition in these forests remain poorly understood. We measured soil organic carbon (SOC), litterfall, root biomass, microbial biomass and soil physical and chemical properties in a wet tropical forest from May 1996 to July 1997 following a 7‐year continuous fertilization. We found that although there was no significant difference in total SOC in the top 0–10 cm of the soils between the fertilization plots (5.42±0.18 kg m −2 ) and the control plots (5.27±0.22 kg m −2 ), the proportion of the heavy‐fraction organic C in the total SOC was significantly higher in the fertilized plots (59%) than in the control plots (46%) ( P <0.05). The annual decomposition rate of fertilized leaf litter was 13% higher than that of the control leaf litter. We also found that fertilization significantly increased microbial biomass (fungi+bacteria) with 952±48 mg kg −1 soil in the fertilized plots and 755±37 mg kg −1 soil in the control plots. Our results suggest that fertilization in tropical forests may enhance long‐term C sequestration in the soils of tropical wet forests.