首页|木麻黄细根形态和化学计量特征对P添加的塑性响应

木麻黄细根形态和化学计量特征对P添加的塑性响应

扫码查看
原文链接
  • 万方数据
  • 维普
探究不同发育阶段木麻黄防护林细根形态和化学计量特征对磷(P)添加的塑性响应规律,为滨海沙地土壤低磷限制下进行木麻黄不同发育阶段有针对性的施肥抚育提供科学依据.以福建省平潭岛木麻黄幼龄林(5 a)、中龄林(12 a)和成熟林(25 a)为研究对象,以内生长土芯法开展P添加试验,细根在内生长芯生长一年后,采用功能划分法对细根形态性状和化学计量特征进行测定.结果表明:(1)P添加显著提高木麻黄细根根长和根表面积,其中,总根长和总表面积总体提高7.79倍、8.69倍,比根长和比表面积总体提升15.1％、19.5％;(2)不同根系功能类群间,细根形态对P添加的塑性响应具有较显著差异,形态塑性以吸收根为主,且吸收根对P养分资源的响应更为敏感,P添加使吸收根P含量总体提高56.0％,C/P和N/P总体降低18.7％和38.7％,组织密度总体降低31.4％;(3)对于土壤P养分资源的变化,不同林龄木麻黄采取不同的塑性响应策略,P添加后,幼龄林主要通过吸收根化学计量特征变异,改变自身生理性状获取P元素,中龄林细根形态和化学计量特征无显著变异,成熟林主要通过改变吸收根形态,扩大根系吸收面积获取P元素.外源P添加可以协调木麻黄细根形态与化学计量特征的内部关系,而不同林龄木麻黄细根在获取P资源时会选择性投资.故在木麻黄施肥抚育时,应根据不同林龄采取针对性的抚育方案.
Plasticity Response of Fine Root Morphology and Stoichiometric Characteristics of Casuarina equisetifolia to Phosphorus Addition
The plasticity response of fine root morphology and stoichiometric characteristics to phosphorus(P)addition in Casuarina equisetifolia forests at different development stages was investigated,providing a scientific basis for targeted fertilization and nurturing of C.equisetifolia at different development stages under the limitation of low phosphorus in coastal sandy soil.The C.equisetifolia plantations at young(5 a),middle-aged(12 a)and mature(25 a)stages were selected as the research objects in Pingtan Island,Fujian Province,and the phosphorus addition experiment was carried out by using the inner growth method.After the fine roots growing in the inner growth cores for a year,the fine root morphological characters and stoichiometric characteristics were measured by the functional division method.The results showed that:1)adding phosphorus significantqly increased the root length and surface area,the total root length and total surface area increased by 7.79 times and 8.69 times,respectively,the specific root length and specific surface area increased by 15.1％and 19.5％,respectively;2)among different root functional groups,the plastic response of fine root morphology to P addition was significantly different.The morphological plasticity was dominated by absorbing roots,and the response of absorbing roots to P nutrient resources was more sensitive.P addition increased the P content in absorbing roots by 56.0％,decreased the C/P and N/P by 18.7％and 38.7％,and decreased the tissue density by 31.4％;3)for the change of soil P nutrient resources,different forest ages of C.equisetifolia adopted different plastic response strategies.After P addition,the young forest mainly obtained P element by changing its own physiological characteristics through the variation of stoichiometric characteristics of absorbing roots.The fine root morphology and stoichiometric characteristics of the middle-aged forest had no significant variation.The mature forest mainly obtained P element by changing the absorbing root morphology and expanding the root absorption area.The present study demonstrates that the addition of exogenous P can coordinate the internal relationship between the fine root morphology and stoichiometric characteristics of C.equisetifolia.Moreover,our results show that the fine roots of C.equisetifolia at different ages selectively invest in acquiring P resources.Thus,to effectively fertilize and nurture C.equisetifolia,targeted tending schemes should be adopted according to the forest's age.

phosphorus additionforest ageabsorptive fine roottransport fine rootfine root morphologyfine root stoichiometryCasuarina equisetifolia

聂森

展开 >

福建省林业科学研究院,福州 350012

P添加 林龄 吸收根 运输根 细根形态 细根化学计量学 木麻黄

福建省省属公益类科研院所基本科研专项中央引导地方科技发展专项福建省林业科技项目

2021R10100072021L3017ZMGG-0704

2024

中国农学通报
中国农学会

中国农学通报

CSTPCD
影响因子：0.891
ISSN：1000-6850
年,卷(期)：2024.40(2)
  • 1
  • 17