摘要
以北京地区3年生侧柏幼树为研究对象,采用温室内盆栽试验,设置5个不同土壤含水量水平,采用15N同位素自然丰度法研究不同水分条件下侧柏幼苗的生理活动、生物量分配及氮素吸收和分配情况。结果表明:(1)在水分胁迫下,侧柏单株净光合速率、呼吸速率、蒸腾速率均表现为最低值,随着干旱胁迫解除,含水量增加到正常值,各指标分别增加为原来的4.86,3.74,7.29倍,叶片含水量和叶面积分别增加了24.37%,23.69%;之后当土壤含水量超过正常值时,随着土壤水分含量的进一步增加,各指标略有下降。(2)在水分胁迫下,生物量分配和氮素分配受到抑制。随着含水量增加,生物量分配表现为地上部分>地下部分;氮素分配率表现为根>叶>茎,随着土壤含水量增加根和叶的氮素分配向茎转移。(3)侧柏幼苗在土壤含水量达到70%~80%的田间持水量时,其生长发育表现为最佳状态。
In this study,the 3-year young lateral cyperusorientalis in Beijing area was selected as the object of study.A greenhouse potted experiment was used to set five different soil water content levels,and 15N isotope natural abundance method was used to study the physiological activities,biomass allocation and nitrogen absorption and distribution of lateral cyperusorientalis seedlings under different water conditions.Results showed that:(1)Under water stress(D1),the individual net photosynthetic rate,transpiration rate and respiratory rate,were low,and increased by 4.86 times,3.74 times,7.29 times after relieving drought stress.The leaf water content and leaf area increased by 24.37%and 23.69%,respectively.After that,when the soil water content exceeded the normal value,with the further increase of soil water content,all indexes decreased slightly.(2)Under water stress,biomass distribution and nitrogen distribution were inhibited.With the increase of water content,biomass distribution was shown as the aboveground part>underground part.The nitrogen distribution rate was shown as follows:root>leaf>stem.The nitrogen in root and leaf were transferred to the stem with the increase of soil water content.(3)When the soil water content reached the 70%to 80%of field water capacity,the growth and development of platycladusorientalis seedlings showed the best.
作者
王鑫
余新晓
贾国栋
邱云霄
史佳美
孜尔蝶
WANG Xin;YU Xinxiao;JIA Guodong;QIU Yunxiao;SHI Jiamei;ZI Erdie(Key Laboratory of Soil & Water Conservation and Desertification Combating of Ministry of Education Beijing Forestry University,Beijing 100083)
出处
《水土保持学报》
CSCD
北大核心
2020年第3期311-317,共7页
Journal of Soil and Water Conservation
基金
国家自然科学基金项目(41430747,41877152)
林果业生态环境功能提升协同创新中心项目(PXM2018_014207_000024)。
关键词
侧柏
水分胁迫
同位素
生理活动
氮素分配
Platycladus orientalis
water stress
isotopes
physiological activity
nitrogen distribution
