Decomposition and nutrient release from radiata pine (Pinus radiata) coarse woody debris
Decomposition and nutrient release from radiata pine (Pinus radiata) coarse woody debris
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DOI：
10.1016/s0378-1127(03)00332-3
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发表时间：
2004-01-23
影响因子：
3.7
通讯作者：
Mahieu, N
中科院分区：
文献类型：
--
作者：
Ganjegunte, GK;Condron, LM;Mahieu, N
研究了新西兰辐射松种植园林间伐迹地分解和养分释放动态。本研究探讨了粗木质残体（CWD）组件（原木，原木树皮，和侧枝）的分解起源于1和13年前之间的林分间伐。组分密度的变化用于估计衰变率。化学分析和C-13核磁共振（NMR）光谱进行了调查分解和化学组成之间的关系。原木的分解速率最快，其次是原木树皮，这反过来又分解速度比侧枝材料。13年后，原木，原木树皮和侧枝失去了59%，55%和24%的初始质量，分别。单指数模型分析表明，总间伐迹地（原木、原木树皮和侧枝之和）的半衰期为13.25年。近似分析表明，原木的分解速度较快，主要是由于较高的碳水化合物浓度，而较高浓度的多酚和木质素的原木树皮的分解速度较慢负责。侧枝分解速度缓慢是由于不利的小气候（即使在分解9年后，大多数侧枝也不与土壤接触）以及木质素和多酚浓度较高。碳-13核磁共振分析表明，在分解过程中的O-烷基和缩醛C，这代表碳水化合物，减少，而N-烷基，芳香族和酚C，这代表单宁和酸不溶性化合物，包括木质素，增加在所有稀斜线组件的相对比例。净释放的营养物质（N，P，K，Ca和Mg）发生在间伐迹地分解过程中，与早期的研究相反，虽然大多数营养物质的浓度随时间的推移而增加。养分释放归因于间伐物质的性质，特别是树皮物质的高比例。虽然有一个净释放，C和大部分养分的释放速率从间伐迹地是缓慢的，使其成为一个重要的C库和长期的营养源。(C)2003 Elsevier B. V.保留所有权利。
The dynamics of decomposition of thinning slash and nutrient release were studied in a radiata pine (Pinus radiata D Don) plantation forest in New Zealand. This study examined decomposition of coarse woody debris (CWD) components (log-wood, log-bark, and side branches) originating from stands thinned between 1 and 13 years previously. Changes in component density were used to estimate the decay rates. Both chemical analyses and C-13 nuclear magnetic resonance (NMR) spectroscopy were conducted to investigate relationships between decomposition and chemical composition. The rate of decomposition was the fastest for log-wood followed by log-bark, which in turn decomposed faster than side-branch material. After 13 years, log-wood, log-bark and side branches lost 59, 55 and 24% of their initial mass, respectively. Single exponential model analysis indicated that the half-life of total thinning slash (sum of log-wood, log-bark and side branches) was 13.25 years. Proximate analyses showed that the faster rate of decomposition of log-wood was mainly due to greater carbohydrate concentration, while greater concentrations of polyphenol and lignin were responsible for the slower decomposition rate of log-bark. The slow rate of decomposition of side branches was due to unfavorable micro-climate (most of the side branches were not in contact with soil even after 9 years of decomposition) as well as greater lignin and polyphenol concentrations. Carbon-13 NMR analysis revealed that during decomposition the relative proportions of O-alkyl and acetal C, which represent carbohydrates, decreased while N-alkyl, aromatic, and phenolic C, which represent tannins and acid insoluble compounds including lignin, increased in all thinning slash components. Net release of nutrients (N, P, K, Ca and Mg) occurred during thinning slash decomposition, in contrast to earlier studies, although the concentrations of most nutrients increased with time. Nutrient release was attributed to the nature of the thinning slash materials and the high proportion of bark material in particular. Although there was a net release, the rate of release of C and the majority of nutrients from thinning slash was slow making it an important C sink and long-term source of nutrients. (C) 2003 Elsevier B.V. All rights reserved.