Addressing controversies in the xylem embolism resistance–vessel diameter relationship

编号 040038503

推送时间 20230306

研究领域 森林培育 

年份 2022 

类型 期刊 

语种 英语

标题 Addressing controversies in the xylem embolism resistance–vessel diameter relationship

来源期刊 New Phytologist

期 第385期

发表时间 20230112

关键词 angiosperm xylem;  data aggregation;  embolism resistance;  functional
traits;  hydraulic conductivity;  pit membrane;  vessel diameter.; 

摘要 Although xylem embolism is a key process during drought-induced tree mortality, its relationship to wood anatomy remains debated. While the functional link between bordered pits and embolism resistance is known, there is no direct, mechanistic explanation for the traditional assumption that wider vessels are more vulnerable than narrow ones.
We used data from 20 temperate broad-leaved tree species to study the inter- and intraspecific relationship of water potential at 50% loss of conductivity (P50) with hydraulically weighted vessel diameter (Dh) and tested its link to pit membrane thickness (TPM) and specific conductivity (Ks) on species level.
Embolism-resistant species had thick pit membranes and narrow vessels. While Dh was weakly associated with TPM, the P50–Dh relationship remained highly significant after accounting for TPM. The interspecific pattern between P50 and Dh was mirrored by a link between P50 and Ks, but there was no evidence for an intraspecific relationship.
Our results provide robust evidence for an interspecific P50–Dh relationship across our species. As a potential cause for the inconsistencies in published P50–Dh relationships, our analysis suggests differences in the range of trait values covered, and the level of data aggregation (species, tree or sample level) studied.

服务人员 孙小满

服务院士 尹伟伦

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