caa a22 4500 606219900 CHVBK 20210128101120.0 cr unu---uuuuu 210128e20150901xx s 000 0 eng 10.1007/s11104-015-2517-2 doi (NATIONALLICENCE)springer-10.1007/s11104-015-2517-2 Differential responses of needle and branch order-based root decay to nitrogen addition: dominant effects of acid-unhydrolyzable residue and microbial enzymes [Elektronische Daten] [Liang Kou, Weiwei Chen, Xinyu Zhang, Wenlong Gao, Hao Yang, Dandan Li, Shenggong Li] Background and aims: Both chemical differences between foliage and different orders of fine roots and their contrasting decomposing microenvironments may affect their decomposition. However, little is known about how foliage and branch order-based root decomposition responds to increased N availability and the response mechanisms behind. Methods: The effects of different doses of N addition on the decomposition of needles and order-based roots of Pinus elliottii (slash pine) were monitored using the litterbag method for 524days in a subtropical slash pine plantation in south China. The acid-unhydrolyzable residue (AUR) concentration and microbial extracellular enzymatic activities (EEA) in decomposing needles and roots were also determined. Results: Our results indicate that the responses of needle and order-based root decomposition were N-dose-specific. The decomposition of both needles and lower-order roots was inhibited under the high N dose rate. The retarded decomposition of lower-order roots could be explained more by the increased binding of AUR to inorganic N ions, while the retarded decomposition of needles could be explained more by the reduced microbial EEA. Further, in contrast to lower-order roots, N addition had no effect on the decomposition of higher-order roots. Conclusions: We conclude that the decomposition of foliage and fine roots may fail to mirror each other at ambient conditions or in response to N deposition due to their contrasting decomposition microenvironments and tissue chemistry. Given the differential effects of N addition on order-based roots, our findings highlight the need to consider the tissue chemistry heterogeneity within branching fine root systems when predicting the responses of root decomposition to N loading. Springer International Publishing Switzerland, 2015 Decomposition nationallicence Fine root nationallicence Foliage nationallicence Microorganism nationallicence Nitrogen deposition nationallicence Kou Liang Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, 100101, Beijing, China aut Chen Weiwei Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, 100101, Beijing, China aut Zhang Xinyu Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, 100101, Beijing, China aut Gao Wenlong Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, 100101, Beijing, China aut Yang Hao Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, 100101, Beijing, China aut Li Dandan Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, 100101, Beijing, China aut Li Shenggong Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, 100101, Beijing, China aut Plant and Soil Springer International Publishing 394/1-2(2015-09-01), 315-327 0032-079X 394:1-2<315 2015 394 11104 https://doi.org/10.1007/s11104-015-2517-2 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/s11104-015-2517-2 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Kou Liang Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, 100101, Beijing, China aut NATIONALLICENCE 700 1- Chen Weiwei Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, 100101, Beijing, China aut NATIONALLICENCE 700 1- Zhang Xinyu Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, 100101, Beijing, China aut NATIONALLICENCE 700 1- Gao Wenlong Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, 100101, Beijing, China aut NATIONALLICENCE 700 1- Yang Hao Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, 100101, Beijing, China aut NATIONALLICENCE 700 1- Li Dandan Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, 100101, Beijing, China aut NATIONALLICENCE 700 1- Li Shenggong Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, 100101, Beijing, China aut NATIONALLICENCE 773 0- Plant and Soil Springer International Publishing 394/1-2(2015-09-01), 315-327 0032-079X 394:1-2<315 2015 394 11104