干旱区生态环境知识资源中心(Arid): 桂西北喀斯特区原生林与次生林凋落叶降解和养分释放

Arid

	桂西北喀斯特区原生林与次生林凋落叶降解和养分释放
其他题名	Litter decomposition and nutrient release in typical secondary and primary forests in karst region,Northwest of Guangxi
	曾昭霞 1; 王克林 1; 曾馥平 1; 宋同清 1; 刘孝利 2; 宋希娟 1
来源期刊	生态学报
ISSN	1000-0933
出版年	2012
卷号	32 期号:9 页码:2720-2728
中文摘要	凋落叶降解及养分释放研究对喀斯特生态脆弱区森林生态系统的恢复与重建具有重要指导意义。选取桂西北喀斯特区3种原生林与3种次生林进行比较,研究其凋落叶降解与降解过程中的营养元素释放规律以及降解速率的影响因子。结果表明,原生林凋落叶的降解速率略大于次生林。C、N、K元素在前180d释放速率较快,随后趋于稳定。次生林凋落叶总P含量在降解初始阶段呈净积累,随后净释放,而原生林的凋落叶在降解360d后仍呈现P素净积累。相关分析表明,凋落叶降解速率与凋落叶初始总N、木质素含量及木质素:N比值呈负相关,与C∶N比呈正相关。综合比较发现,次生林圆叶乌桕(Sapiumrotundifolium Hemsl)凋落叶的降解速率与养分释放速率较快,是喀斯特退化土地及植被恢复过程中潜在的优势种和建群种。
英文摘要	Karst ecosystem has been shown to be extremely vulnerable under severe water and soil erosion due to improper land uses and human activities.The karst area of Southwestern China covers a land of 550000 km2 but 105000 km2 of that is suffering from serious rocky desertification.Recently,national and provincial afforestation programs have been developed to protect and/or restore the degraded karst lands.Litter decomposition is the major pathway to provide organic and inorganic elements for the nutrient cycling processes and control nutrient return to the forest ecosystem.So,leaf litter decomposition and nutrient release characteristics play an important and leading role in the forest ecosystem restoration and reconstruction in the fragile karst region.In view of litter fall as the important component of forest ecosystem and the shortage study about karst area in southwest China,confronting the restoration programs.Litter bag decomposition experiments were set up at six sites to compare the litter decomposition differentiation under different karst forest ecosystems from Dec.2008 until Nov.2009.In this study,three typical primary forest communities(Dye-tree(Platycarya longipes Wu),Eurycorymbus(Eurycorymbus cavaleriei Hand.,Wing-hackberry(Pteroceltis tatarinowii Maxim)) and three typical secondary forest ones(Round-leaved Tallow-tree(Sapium rotundifolium Hemsl),Chinese Alangium(Alangium chinense(Lour.)Harms),Negundo Chaste-tree(Vitex negundo Linn)) were chosen to elucidate the decomposition characteristics of leaf litter,release pattern of nutrient elements over the course of leaf litter decomposition,decomposition rate and related impact factors in Karst areas of northwest Guangxi of China.The result showed that the decay rates of leaf litter at primary forests were slightly faster than that of secondary forest.Release rates of carbon(C),nitrogen(N) and Potassium(K) were generally higher within initial 180 days and then tended to become stable.The content of total phosphorus(TP) in leaf litter in secondary forest communities displayed a status of net accumulation at the initial stage of decomposition,and subsequently turned to be replaced by a net release.However,the TP content of leaf litter in primary forest communities was remained in net accumulation status till 360 days after litter presence.Correlation analysis showed that decomposition rate of leaf litter was negatively correlated with total initial N content,lignin content and lignin to nitrogen ratio in leaf litter,whereas was positively correlated with leaf C/ N ratio.Comprehensive and comparative analysis suggested that leaf litter decomposition rate and nutrient element release rate within the round-leaved tallow tree(Sapium rotundifolium Hemsl) community were totally greater in secondary forests than those of primary forest communities.With regard to species choices for the re-establishment of nutrient cycling in disturbed forest ecosystems,species with high nutrient recycling capacity(e.g.species with fast litter decomposition rate) may be favored.In this study,it can be argued that the tallow tree could act as a potential constructive and dominant species in the restoration of degraded Karst land and vegetation.So our study results can provide some support and refer for national and provincial afforestation programs in Karst areas of northwest Guangxi of China.
中文关键词	喀斯特 ; 原生林 ; 次生林 ; 凋落叶降解 ; 养分释放
英文关键词	karst primary forest secondary forest leaf litter decomposition nutrient release
语种	中文
国家	中国
收录类别	CSCD
WOS类目	FORESTRY
WOS研究方向	Forestry
CSCD记录号	CSCD:4539562
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/228447
作者单位	1.中国科学院亚热带农业生态研究所, 中国科学院亚热带农业生态过程重点实验室, 长沙, 湖南 410125, 中国; 2.湖南农业大学资源环境学院, 长沙, 湖南 410128, 中国
推荐引用方式 GB/T 7714	曾昭霞,王克林,曾馥平,等. 桂西北喀斯特区原生林与次生林凋落叶降解和养分释放[J],2012,32(9):2720-2728.
APA	曾昭霞,王克林,曾馥平,宋同清,刘孝利,&宋希娟.(2012).桂西北喀斯特区原生林与次生林凋落叶降解和养分释放.生态学报,32(9),2720-2728.
MLA	曾昭霞,et al."桂西北喀斯特区原生林与次生林凋落叶降解和养分释放".生态学报 32.9(2012):2720-2728.