Search results for "shoot age"

showing 3 items of 3 documents

Shoot age as a confounding factor on detecting the effect of human-induced disturbance on Posidonia oceanica growth performance

2007

Abstract The response of orthotropic rhizome elongation and primary production of Posidonia oceanica to anthropogenic perturbations and potential confounding effects of shoot age were assessed using a Linear Multilevel Model (LMM). This model examined the confounding effect of age by comparing the estimates of impact and variance components obtained by excluding and including Age as an explanatory variable. Age had a negative effect on rhizome elongation and primary production with an annual decrease of 0.6 mm y − 1 and 7 mg dw y − 1 respectively. According to the LMM when age effect was omitted, the differences between disturbed and control locations in rhizome elongation and primary produ…

PotamogetonaceaeAge effectbiologyConfoundingConfounding Lepidochronology Linear Mixed Models Posidonia oceanica Shoot ageAquatic Sciencebiology.organism_classificationConfounding effectRhizomeAnimal sciencePosidonia oceanicaBotanyShootVariance componentsEcology Evolution Behavior and SystematicsJournal of Experimental Marine Biology and Ecology
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Effect of different substrata on rhizome growth, leaf biometry and shoot density of Posidonia oceanica

2013

The effects of different substratum typologies on Posidonia oceanica growth and morphology were estimated in four Sicilian meadows using Generalized and Linear Mixed Models combined with retrodating and biometric analyses. Substratum exerted a multiple effect, resulting in different biometric features for P. oceanica shoots settled on rock from those growing on sand and matte. On rock, values for growth rate, leaf length and shoot surface were lower than those on other substrata, with 42%, 23% and 32% the highest degree of difference respectively. The present study may have interesting methodological consequences for the comprehensive understanding of the causative variables potentially aff…

Settore BIO/07 - EcologiaGeologic SedimentsAlismatalesbiologyGeneral MedicineBiomonitoring benthic ecology seagrass Posidonia oceanica substratum lepidochronology leaf biometry shoot age GLMM LMMAquatic ScienceOceanographybiology.organism_classificationModels BiologicalPollutionRhizomePlant LeavesSeagrassBenthic zonePosidonia oceanicaShootBotanyLinear ModelsSicilyRhizomeEnvironmental MonitoringMarine Environmental Research
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Modelling the relationship between sexual reproduction and rhizome growth in Posidonia oceanica (L.) Delile

2006

The relationship between flowering and growth performance of Posidonia oceanica (L.) Delile in meadows distributed along the south-eastern coast of Sicily (Italy) was investigated by means of a statistical model (generalized linear mixed model) combined with the lepidochronological analysis. Over a 28-year period, 67 floral stalk remains were observed. The highest flowering index was recorded in lepidochronological year 1998 (10.1%) and the Inflorescence Frequency per age showed a clear decrease corresponding to 15-year-old shoots. The sexual reproductive event had positive effects on rhizome elongation (cm year−1) and leaf production (no. leaves year−1) in the same flowering year, whilst n…

sexual reproductionEcologybiologyfungiStress inducedlepidochronologyPosidonia oceanicafood and beveragesAquatic Sciencebiology.organism_classificationshoot ageRhizomeSexual reproductionInflorescencegeneralized linear mixed modelPosidonia oceanicaShootBotanyEcology Evolution Behavior and SystematicsMarine Ecology
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