林业科学Issue(7)：1-8,8.DOI:10.11707/j.1001-7488.20150701
湖南会同3个林龄杉木人工林土壤碳、氮、磷化学计量特征
Stoichiometry Characterization of Soil C,N,and P of Chinese Fir Plantations at Three Different Ages in Huitong,Hunan Province,China
摘要
Abstract
[Objective]Soil organic C,total N ,and total P were measured in Chinese fir plantations at 3 different ages (7-,17-,and 25-year-old) and changes of these elements along soil profile were also investigated in these plantations,in order to provide a scientific basis for sustainable management of Chinese fir plantations. [Method]The study was conducted at the National Key Field Observation Station of Central South University of Forestry and Technology,located in Huitong,Hunan Province of China. Three plantations at different ages were selected within the station and three plots in size of 20 m × 20 m were set up for each of the three plantations. Based on the principle of‘random’,‘equal’and‘pooled’,soil samples were collected from 0 -20,20 -40,and 40 -60 cm depths,respectively,at three sampling points with a triangle shape within each plot. Soil organic C,total N and total P were analyzed. C∶N,C∶P,N∶P and C∶N∶P ratios were estimated. [Result]The contents of soil organic C,total N ,and total P ranged 12. 14 -19. 52, 1. 43 -1. 89,and 0. 32 -0. 40 g·kg -1 in the studied plantations,respectively. The contents of soil organic C and total N decreased with the increase of soil depths in 7-,17-and 25-year-old stands. Total P contents did not significantly differ among soil depths in the studied stands. Soil C∶ N of the 3 plantations was respectively 11. 73,8. 70,and 8. 52, displaying a declining trend with aging. . In addition,soil C∶ N ratio was significantly higher in 7-year-old plantations ( P<0 . 05 ) and significantly lower in 17-and 25-year-old plantations ( P <0 . 05 ) when compared to the control plots (9. 52) (plots with slash burning but before afforestation). Soil C∶P ratios were 57. 42,36. 27 ,and 40. 54 in the studied plantations and 55. 70 in the control,which were all lower than the national mean (61). Soil C∶P ratios were significantly higher in 7-year-old plantations and the control plots than in 17-and 25-year old plantations. Soil N∶P ratios were 4. 87, 4. 18 and 4. 76 in the studied plantations and no significant differences from each other. But soil N∶P ratios were lower in the studied plantations compared to the national mean (5. 2),and significantly lower when compared to the control (5. 85) (P<0. 05). Soil C∶N∶P ratios were 56∶5∶1,36∶4∶1,41∶5∶1 in the three plantations and 55∶6∶1 in the control, all were lower than the national mean (60∶5∶1).[Conclusion]Soil C,N ,and P contents were gradually restored with the aging of plantations. Our study suggested that N was relatively adequate,but P was relatively lack in the studied sites. It was likely that net mineralization of soil microbial biomass P occurred in order to maintain a relative equilibrium of P in soils under low soil C∶P ratio condition. Soil C∶N,N∶P ,and C∶P ratios were in a relative steady state along soil profile in the plantations. Soil C∶N and C∶P ratios were mainly affected by soil total C in the study area. As a consequence,to regulate soil organic C content is a critical target in sustainable management of Chinese fir plantations.关键词
杉木人工林/土壤/碳/氮/磷/生态化学计量/林分年龄Key words
Chinese fir plantation/soil/carbon/nitrogen/phosphorus/stoichiometry/plantation age分类
农业科技引用本文复制引用
曹娟,闫文德,项文化,谌小勇,雷丕锋..湖南会同3个林龄杉木人工林土壤碳、氮、磷化学计量特征[J].林业科学,2015,(7):1-8,8.基金项目
国家林业公益性行业科研专项(201404316) （201404316）
湖南省自然科学基金创新群体项目(湘基金委字［2013］7号) （湘基金委字［2013］7号）
城市森林生态湖南省重点实验室运行项目 （）
湖南省优势重点学科项目 （）
湖南省“百人计划”项目(0842) （0842）
中南林业科技大学研究生科技创新基金项目(CX2014A04) （CX2014A04）
国家林业局软科学研究项目(2013－R09) （2013－R09）
中南林业科技大学青年科学基金项目“杉木林健康经营技术研究”。 （）
