Sampling procedure for the foliar analysis of deciduous trees

Abstract

Sampling can be the source of the greatest errors in the overall results of foliar analysis. This paper reviews the variability in heavy metal concentrations in tree crowns, which is a feature that should be known and understood when designing a suitable leaf sampling procedure. The leaf sampling procedures applied in 75 articles were examined. Most of the environmental studies used a closely related form of the UN/ECE-EC leaf sampling procedure, which was developed for the long-term monitoring of forest condition. Studies with objectives outside the UN/ECE-EC field of application should utilize a sampling procedure that is in accordance with the objectives of the study and based on the observed variation in pilot and similar studies. The inherent sources of heavy metal variability inside the stand, i.e. the crown class, stand management, site properties, crown dimensions, infections, seasons, etc. were discussed, but the underlying causes of this variability are rarely understood. The inherent variability in tree crowns is the reason for using leaf sampling as a tool in pollution studies. The objectives of a pollution study determine which sources of variability are utilized by the researcher.

Effects of living crown reduction on needle element status of Scots pine

“…Considerable effort has been put in finding better solutions that would increase the diagnostic value of the foliar analysis of the trees (e.g. Braekke et al 1998, Helmisaari 1998, Rautio 2000, Brockley 2001, Luyssaert et al 2002. Scientific value and objective interpretation are important key questions in maintaining and improving the usability of foliar analysis in different fields of environmental monitoring.…”

“…On the whole, there is clearly insufficient information on this phenomenon and its causal effects, particularly when interpreting the results of foliar analyses or nutritional recovery abilities of severely defoliated Scots pine stands. As foliar element analysis is a widely used tool to describe, indicate and predict the growth, nutritional, environmental and health status (Luyssaert et al 2002) of trees, including crown condition and defoliation monitoring (Lindgren et al 2000, Merilä et al 2007), I considered it important to investigate the possible interactions between rapid living crown reduction and the foliar element status of the trees.…”

Diagnostic leaf to evaluate the nutritional status of Jatropha

“…The greater sensitivity of the index leaf collected in the top third of the canopy may be related to the fact that in perennial plants, much of the metabolically active leaves are located in this part of the canopy (Luyssaert et al, 2002). Thus, it is permissible to indicate this sampling pattern as index leaf for diagnosing the nutritional status of adult plants of Jatropha.…”

“…Younger plants have less shading of leaves, both in the basal and in the distal part of the branch, due to lower development of the tree canopy and, therefore, to less competition for light. According to Luyssaert et al (2002), exposure to light may affect the leaf contents, due to differences in the translocation of nutrients and carbohydrates among the leaves and the transpiration rate. Therefore, the pattern of spatial distribution between the leaves more exposed to light and shaded leaves may result in differences in the accumulation of nutrients in different parts of the plant canopy.…”

Foliar Nutrient Composition of 19 Tree Species Grown on a Phytocapped Landfill Site

“…Trees store most nutrients in the leaves [8]. Similarly, trees take up heavy metals and store them in the leaves and branches [9][10][11] to protect themselves from insects and fungi [12]. Nutrients that are taken up by trees are eventually distributed to the environment via litter fall [13][14][15].…”