+ Site Statistics
+ Search Articles
+ PDF Full Text Service
How our service works
Request PDF Full Text
+ Follow Us
Follow on Facebook
Follow on Twitter
Follow on LinkedIn
+ Subscribe to Site Feeds
Most Shared
PDF Full Text
+ Translate
+ Recently Requested

Photosynthesis-nitrogen relations in Amazonian tree species : II. Variation in nitrogen vis-a-vis specific leaf area influences mass- and area-based expressions



Photosynthesis-nitrogen relations in Amazonian tree species : II. Variation in nitrogen vis-a-vis specific leaf area influences mass- and area-based expressions



Oecologia 97(1): 73-81



The relationships between leaf nitrogen (N), specific leaf area (SLA) (an inverse index of leaf "thickness" or "density"), and photosynthetic capacity (Amax) were studied in 23 Amazonian tree species to characterize scaling in these properties among natural populations of leaves of different ages and light microenvironments, and to examine how variation within species in N and SLA can influence the expression of the Amax-to-N relationship on mass versus area bases. The slope of the Amax-N relationship, change in A per change in N (μmol CO2 gN-1 s-1), was consistently greater, by as much as 300%, when both measures were expressed on mass rather than area bases. The x-intercept of this relationship (N-compensation point) was generally positive on a mass but not an area basis. In this paper we address the causes and implications of such differences. Significant linear relationships (p<0.05) between mass-based leaf N (Nmass) and SLA were observed in 12 species and all 23 regressions had positive slopes. In 13 species, mass-based Amax (Amass) was positively related (p<0.05) with SLA. These patterns reflect the concurrent decline in Nmass and SLA with increasing leaf age. Significant (p<0.05) relationships between area-based leaf N (Narea) and SLA were observed in 18 species. In this case, all relationships had negative slopes. Taken collectively, and consistent in all species, as SLA decreased (leaves become "thicker") across increasing leaf age and light gradients, Nmass also decreased, but proportionally more slowly, such that Narea increased. Due to the linear dependence of Amass on Nmass and a negative 4-intercept, "thicker" leaves (low SLA) therefore tend, on average, to have lower Nmass and Amass but higher Narea than "thinner" leaves. This tendency towards decreasing Amass with increasing Narea, resulting in a lower slope of the Amax-N relationship on an area than mass basis in 16 of 17 species where both were significant. For the sole species exception (higher area than mass-based slope) variation in Narea was related to variation in Nmass and not in SLA, and thus, these data are also consistent with this explanation. The relations between N, SLA and Amax explain how the rate of change in Amax per change in N can vary three-fold depending on whether a mass or area mode of expression is used.

Please choose payment method:






(PDF emailed within 0-6 h: $19.90)

Accession: 060092263

Download citation: RISBibTeXText

PMID: 28313591

DOI: 10.1007/bf00317910


Related references

Photosynthesis-Nitrogen Relations in Amazonian Tree Species. Ii. Variation in Nitrogen Vis-a-Vis Specific Leaf Area Influences Mass- and Area-Based Expressions. Oecologia 97(1): 73-81, 1994

Photosynthesis-nitrogen relations in Amazonian tree species: II. Variation in nitrogen vis-a-vis specific leaf area influences mass- and area-based expression. Oecologia 97(1): 73-81, 1994

Leaf structure (specific leaf area) modulates photosynthesis-nitrogen relations: evidence from within and across species and functional groups. Functional Ecology 12(6): 948-958, 1998

Leaf Structure (Specific Leaf Area) Modulates Photosynthesis-Nitrogen Relations: Evidence from within and Across Species and Functional Groups. Functional Ecology 12(6): 948-958, 1998

Spatial and temporal variations in leaf area index, specific leaf area and leaf nitrogen of two co-occurring savanna tree species. Tree physiology 24(2): 205-216, 2004

Reconciling the apparent difference between mass- and area-based expressions of the photosynthesis-nitrogen relationship. Oecologia 118(2): 144-150, 1999

Reconciling the Apparent Difference between Mass- and Area-Based Expressions of the Photosynthesis-Nitrogen Relationship. Oecologia 118(2): 144-150, 1999

Distribution of leaf mass per unit area and leaf nitrogen concentration determine partitioning of leaf nitrogen within tree canopies. Tree Physiology 20(4): 271-276, 2000

Distribution of leaf mass per unit area and leaf nitrogen concentration determine partitioning of leaf nitrogen within tree canopies. Tree Physiology 20(4): 271-276, 2000

Photosynthesis-nitrogen relations in Amazonian tree species : I. Patterns among species and communities. Oecologia 97(1): 62-72, 1994

Photosynthesis-nitrogen relations in Amazonian tree species: I. Patterns among species and communities. Oecologia 97(1): 62-72, 1994

Photosynthesis and leaf nitrogen in five Amazonian tree species during early secondary succession. Ecology (Washington D C) 77(2): 581-594, 1996

Acclimation of leaf respiration to temperature is rapid and related to specific leaf area, soluble sugars and leaf nitrogen across three temperate deciduous tree species. Functional Ecology 19(4): 640-647, 2005

Acclimation of Leaf Respiration to Temperature Is Rapid and Related to Specific Leaf Area, Soluble Sugars and Leaf Nitrogen across Three Temperate Deciduous Tree Species. Functional Ecology 19(4): 640-647, 2005

Plastic changes of leaf mass per area and leaf nitrogen content in response to canopy openings in saplings of eight deciduous broad-leaved tree species. Ecological Research 20(1): 17-23, 2005