摘要
本研究在大兴安岭北部典型泥炭地开展长期原位氮磷添加试验,研究氮(6 g N·m^(-2)·a^(-1))、磷(2 g P·m^(-2)·a^(-1))添加4、6和8年后物种优势度、群落多样性和地上部生物量,分析养分有效性增加对植物群落结构的影响。结果表明:磷添加对落叶灌木、常绿灌木、莎草、禾草、杂类草、苔藓和地衣优势度没有显著影响;而氮添加显著提高了落叶灌木和禾草重要值及优势度,降低了苔藓和地衣重要值及优势度,而且影响幅度随着试验年限增加而增加。氮和磷添加均降低了物种丰富度、多样性和均匀度,其中氮添加引起的物种多样性降低主要由常绿灌木、苔藓和地衣消失引起,而磷添加引起的物种多样性降低则主要由杂类草、苔藓消失引起。磷添加没有改变植物地上部生物量,但氮添加导致常绿灌木、苔藓和地衣的地上部生物量降低,并引起落叶灌木和禾草地上部生物量增加。氮和磷添加对植物地上部生物量产生显著的交互作用,氮添加和氮磷同时添加处理地上部生物量比对照分别显著高87%和128%。研究表明,养分富集能促进植物生长,但引起物种多样性降低,而且影响强度随时间延长而增大。
To analyze the impacts of increased nutrient availability on plant community structure,we conducted a long-term field N and P addition experiment in a typical peatland in the north of Greater Khingan Mountain and investigated species dominance,community diversity,and aboveground biomass after four,six,and eight years of N(6 g N·m^(-2)·a^(-1))and P(2 g P·m^(-2)·a^(-1))addition.The results showed that P addition did not affect the dominances of deciduous shrub,evergreen shrub,sedge,grass,forb,moss,and lichen.However,N addition significantly increased the importance values and dominances of deciduous shrub and grass but reduced the importance values and dominances of moss and lichen.The magnitude of N addition effects increased with elevating experimental duration.Both N and P addition decreased species richness,diversity,and evenness.The N addition-induced decline in species diversity primarily resulted from the disappearance of evergreen shrub,moss,and lichen,whereas decreased species diversity under P addition were mainly caused by the loss of forb and moss.Phosphorus addition did not affect aboveground biomass of plants,while N addition significantly reduced aboveground biomass of evergreen shrub,moss,and lichen and increased that of deciduous shrub and grass.Nitrogen and P addition produced a significant interaction on aboveground plant biomass in this community.Nitrogen addition and combined N and P addition treatments had 87%and 128%greater aboveground plant biomass than the control,respectively.These results suggested that nutrient enrichment could promote plant growth but induce reductions in species diversity,and such effect would be amplified by increasing experimental duration.
作者
曾真
于乐琳
张新厚
毛瑢
ZENG Zhen;YU Lelin;ZHANG Xinhou;MAO Rong(Key Laboratory of National Forestry and Grassland Administration on Forest Ecosystem Protection and Restoration of Poyang Lake Watershed,College of Forestry,Jiangxi Agricultural University,Nanchang 330045,China;CAS Key Laboratory of Wetland Ecology and Environment,Institute of Northeast Geography and Agroecology,Chinese Academy of Sciences,Changchun 130102,China;Matoushan Observation and Research Station of Forest Ecosystem,Fuzhou 335300,Jiangxi,China)
出处
《应用生态学报》
北大核心
2025年第8期2353-2360,共8页
Chinese Journal of Applied Ecology
基金
国家自然科学基金项目(42371051)资助。
关键词
北方泥炭地
氮沉降
养分富集
物种多样性
植物生物量
boreal peatland
nitrogen deposition
nutrient enrichment
species diversity
plant biomass
