退化红壤重建森林初期细根特征及其作用机理研究  

Fine-root character and its action mechanism of forest at its initial reestablished stage on degraded red soil.

作　　者：刘苑秋[1] 罗良兴[2] 刘亮英[1] 杨家林 夏晓兰[1] 

机构地区：[1]江西农业大学林学院,南昌330045 [2]江西省泰和县林业局,泰和343700 [3]南昌市林业局,南昌330000

出　　处：《应用生态学报》2005年第9期1735-1739,共5页Chinese Journal of Applied Ecology

基　　金：国家自然科学基金项目(30371150);江西省自然科学基金资助项目(0230037).

摘　　要：以江西泰和严重退化红壤上不同模式重建的森林第10年森林生态系统为对象,分析了细根分布特征及其与土壤性状相关性.结果表明,各重建森林模式的土壤细根主要分布在0～20 cm土层,占0～40cm土层的73.39%～87.41%;不同重建森林模式细根的养分贮量有较明显差异,中等栽植密度晚松纯林细根的全N、全P和全K贮量远远高于其它林地,细根中全N、全P、全K、Ca、Mg贮量分别达84.47、5.55、38.42、17和10.76kg·hm-2;土壤有机质、全N、有效N、有效K、pH值与细根现存量相关显著(P＜0.05),细根对物理性状的影响主要体现在毛管孔隙度和总孔隙度上;植物细根显著提高了＞5 mm土壤水稳性团聚体及＞0.25 mm水稳性团聚体含量,从而增加了土壤结构的稳定性;土壤细根与土壤细菌和微生物总数相关性显著.This paper studied the fine-root character and its action mechanism of forest reestablished by different models for 10 years on a seriously degraded red soil, and analyzed their correlation with soil property. The results showed that fine-roots mostly distributed in 0--20 cm soil layer, accounted for 73.39 % --87.41% of those in 0- 40 cm soil layer. There were notable differences in nutrient storage of fine-roots under different reestablishment models. The fine- roots of medium density pure Pinus serotina forest had a much higher storage of total nitrogen, phosphorus and potassium, with the content of total nitrogen, phosphorus, potassium, calcium and magnesium being 84.47, 5.55, 38.42, 17.00 and 10.76 kg·hm^- 2, respectively. Soil organic matter, total nitrogen, available nitrogen, available potassium and pH had significant correlations with fine-root biomass （P 〈 0.05）. The effects of fine-roots on soil physical properties mainly reflected on soil capillary porosity and total porosity. Fine-roots obviously increased the contents of 〉0.25 mm and 〉 5 mm soil waterstable aggregates, and improved soil structurestability. The correlations between fine-roots and soil bacteria and microbial quantities were significant.

关 键 词：退化红壤 重建森林 细根 作用机理 

分 类 号：S718.55[农业科学—林学]