Mokany2003
Data contributor: Karel Mokany
Email: Karel.Mokany@csiro.au
Address:
- CSIRO Land and Water Flagship, Black Mountain Laboratories, Clunies Ross Street, Black Mountain ACT 2601, Australia
Citation: Mokany K, McMurtrie RE, Atwell BJ and Keith H (2003). 'Interaction between sapwood and foliage area in alpine ash (Eucalyptus delegatensis) trees of different heights.' Tree Physiology, 23(14), pp. 949-958.
DOI: 10.1093/treephys/23.14.949
Abstract: In native stands of Eucalyptus delegatensis R. T. Baker, sapwood area (As) to foliage area (Af) ratios ({As:Af)} decreased as tree height increased, contradicting the common interpretation of the Pipe Model Theory as well as the generally observed trend of increasing {As:Af} ratios with tree height. To clarify this relationship, we estimated sapwood hydraulic conductivity theoretically based on measurements of sapwood vessel diameters and Poiseuille's law for fluid flow through pipes. Despite the observed decrease in {As:Af} ratios with tree height, leaf specific conductivity increased with total tree height, largely as a result of an increase in the specific conductivity of sapwood. This observation supports the proposition that the stem's ability to supply foliage with water must increase as trees grow taller, to compensate for the increased hydraulic path length. The results presented here highlight the importance of measuring sapwood hydraulic conductivity in analyses of sapwood-foliage interactions, and suggest that measurements of sapwood hydraulic conductivity may help to resolve conflicting observations of how {As:Af} ratios change as trees grow taller.
The dataset includes records for 24 individuals from 1 species belonging to 1 family(ies), presenting 1 functional type(s), growing in 1 condition(s) within 1 major type(s) of habitat, with data included for the following variables:
| Variable | Label | Units | N | Min | Median | Max |
|---|---|---|---|---|---|---|
| latitude | Latitude | deg | 24 | -36 | -36 | -36 |
| longitude | Longitude | deg | 24 | 148 | 148 | 148 |
| age | Age | yr | 24 | 4 | 20 | 54 |
| a.lf | Leaf area | m2 | 24 | 0.3 | 29 | 722 |
| a.ssba | Sapwood area at base | m2 | 24 | 0.000078 | 0.0077 | 0.08 |
| a.shba | Heartwood area at base | m2 | 24 | 0 | 0.006 | 0.28 |
| a.stba | Stem area at base | m2 | 18 | 0.0008 | 0.036 | 0.52 |
| h.t | Height | m | 24 | 2.3 | 15 | 41 |
| h.c | Height to crown base | m | 24 | 0.8 | 6.3 | 23 |
| d.ba | Basal diameter | m | 18 | 0.032 | 0.21 | 0.81 |
| c.d | Crown depth | m | 24 | 1.3 | 8.3 | 23 |
| m.lf | Leaf mass | kg | 24 | 0.037 | 4.6 | 117 |
And locally within the country:
The sites sampled are:
| Location | Longitude | Latitude | Vegetation |
|---|---|---|---|
| Bago and Maragle State Forests, NSW, Australia | 148.5 | -35.7 | Temperate forest |
The growing conditions of sampled plants was:
| Location | growingCondition |
|---|---|
| Bago and Maragle State Forests, NSW, Australia | field wild |
| Species | Family | Pft |
|---|---|---|
| Eucalyptus delegatensis | Myrtaceae | evergreen angiosperm |
Sampling strategy: We destructively sampled 13 suppressed trees (growing under a canopy of taller dominant trees) with heights ranging from 2.3 to 35.1 m, plus eleven dominant trees (forming the canopy of a stand with direct access to sunlight) with heights ranging from 2.6 to 41.3 m. Each sample tree was felled and a range of measurements undertaken.
Leaf area: The basal diameters of all primary branches on each tree were measured, and foliage mass for each tree estimated using an existing allometric relationship between branch diameter and foliage mass. Once the foliage dry mass for each branch on each tree had been estimated by applying the existing allometric relationship, the estimated foliage dry masses were totalled for each tree. Specific leaf area was determined for three groups of leaves; namely, adult, juvenile and intermediate morphologies; in each group, the area of 100 fresh leaves was measured with a Model 3100 area meter (Li-Cor, Lincoln, NE), and leaf dry mass determined. Whole-tree foliage area was then determined by multiplying the total foliage mass for each tree by the relevant specific leaf area value for the leaves on that tree (e.g., the juvenile SLA value for trees composed of juvenile leaves).
Stem cross sectional area: Two stem disks (about 4 cm thick) were taken from each tree, one at the base of the stem (BH = basal height about 40 cm above ground level) and the other at the BLC. After sanding each disk with coarse and then fine sandpaper, sapwood was clearly distinguishable from heartwood by its lighter color. The area of sapwood for each stem disk was traced onto tracing paper. The tracing was cut out, sprayed with paint, and its area measured with a Li-Cor Model 3100 area meter.
Height: Each sample tree was felled and its overall height and the height to the base of the live crown (BLC) measured.
Biomass: The basal diameters of all primary branches on each tree were measured, and foliage mass for each tree estimated using an existing allometric relationship between branch diameter and foliage mass. Once the foliage dry mass for each branch on each tree had been estimated by applying the existing allometric relationship, the estimated foliage dry masses were totalled for each tree. Leaves were dried at 80degC for 7 days for measurement of dry mass.
Traits: Specific leaf area was determined for three groups of leaves:, adult, juvenile and intermediate morphologies. In each group, the area of 100 fresh leaves was measured with a Model 3100 area meter (Li-Cor, Lincoln, NE).
Year collected: 2000
This is how the study Mokany2003 fits in the entire dataset (grey). each colour represents a species. A legend of species names with colours is included at the end for reports with 1 < n < 20 species.
