摘要
调整叶性状和生长速率是植物适应环境变化的主要生存策略.为探究不同氮磷添加下植物生长与叶性状及土壤养分的关系,并验证生长速率假说对不同氮磷添加下刨花楠生长的适用性,以利用1年生苗木营造的刨花楠(Machilus pauhoi)人工幼林为研究对象,在造林后第2年,开展不同比例氮磷养分添加试验,测定其地径、株高、叶片形态、碳氮磷养分及土壤养分等指标,分析氮磷添加对刨花楠生物量相对生长速率与叶性状及土壤养分关系的影响.结果显示:在氮添加量为N 100 kg hm^(-2)a^(-1)时,随氮磷比降低,刨花楠叶片形态指数、比叶面积、叶片氮含量及叶片磷含量均呈先增后减的趋势,而叶片C:N、叶干物质含量、叶片相对含水率则呈相反变化;合理添加氮磷可促进刨花楠生长,N:P=10:1(NP2)处理显著促进刨花楠地径增大,该处理下生物量相对生长速率也稍高于其他处理.氮磷添加改变了刨花楠生物量相对生长速率与叶性状及土壤养分的关系,回归结果表明,未施肥、N:P=12:1(NP3)、N:P=15:1(NP4)时,刨花楠生长速率与叶片N:P呈线性相关;但当N:P=8:1(NP1)时则转换为二次曲线相关.通过回归预测模型确定,当N:P=8:1、N:P=10:1时,刨花楠相对生长速率主要受叶片形态指数影响,而其他施肥处理(NP3、NP4)则主要受土壤总磷控制.本研究表明,影响植物生物量相对生长速率的主要因素不仅包括叶片氮磷含量及N:P,土壤养分及叶片表型性状也是重要影响因素;结果可为刨花楠人工幼林养分管理及高效经营等提供理论依据.
Adjusting leaf traits and growth rates are the major survival strategies of plants to adapt to environmental changes.This study aimed to investigate the relationship between plant growth,and leaf traits-soil nutrients under different rates of nitrogen(N)and phosphorus(P)additions and verify the adaptability of the growth rate hypothesis of Machilus pauhoi under different nutrient additions.We used a young plantation of M.pauhoi cread from 1-year-old seedlings.In the second year after planting,we analyzed the effects of different rates of N and P nutrient additions in the relative growth rate of plantain biomass with respect to leaf traits and soil nutrients.We measured ground diameter,plant height,leaf morphology,and carbon(C),N,and P nutrients in both plant and soil.The results indicated that,with an addition of 100 kg hm^(-2)a^(-1)of N,morphological index,specific area,N concentration,and P concentration of the M.pauhoi leaf showed significant trends of increase and decrease with the decrease in N and P addition ratio,while the trends in C:N,dry matter content,and relative water content in leaf were contrasting.We observed that the N:P=10:1(NP2)treatment significantly increased the ground diameter of plantain,and the relative growth rate of biomass was slightly higher in this treatment than that in the other treatments.Addition of N and P altered the relative growth rate of M.pauhoi biomass with respect to leaf traits and soil nutrients.Regression analysis showed that the growth rate of plantain was linearly correlated with leaf N:P when no fertilizer was applied,as well as at N:P=12:1(NP3)and N:P=15:1(NP4),and converted to a quadratic curve when N:P=8:1(NP1).The regression prediction model revealed that the relative growth rate of M.pauhoi was mostly influenced by the leaf morphological index when N:P=8:1 and N:P=10:1,while the other fertilization treatments were majorly controlled by soil total P concentration.The results suggest that,in addition to leaf N,P,N:P ratio,and soil nutrients,leaf phenotypic traits are the dominant factors that need to be considered during evaluation of the growth rate hypothesis.These results can provide a theoretical basis for nutrient management and efficient management of young plantation forests.
作者
林秋燕
钟全林
李宝银
徐朝斌
程栋梁
余华
邹宇星
张志浩
LIN Qiuyan;ZHONG Quanlin;LI Baoyin;XU Chaobin;CHENG Dongliang;YU Hua;ZOU Yuxing;ZHANG Zhihao(College of Geographical Sciences,Fujian Normal University,Fuzhou 350007,China;State Key Laboratory Breeding Base of Humid Subtropical Mountain Ecology,Fuzhou 350007,China;Fujian Province Key Laboratory of Plant Ecophysiology,Fujian Normal University,Fuzhou 350007,China;College of Geography and Oceanography,Minjiang University,Fuzhou 350108,China)
出处
《应用与环境生物学报》
CAS
CSCD
北大核心
2023年第5期1068-1076,共9页
Chinese Journal of Applied and Environmental Biology
基金
国家自然科学基金项目(31971643,32071555)
中央财政推广项目(JXTG[2022]09)
福建省科技厅高校产学合作项目(2023N5006)
福建省林业局项目(2020TG21,2021FKJ29,2022FKJ24)资助
关键词
氮磷比
叶性状
相对生长速率
土壤养分
人工幼林
刨花楠
nitrogen and phosphorus ratio
leaf trait
relative growth rate
soil nutrient
young plantation forest
Machilus pauhoi
