Water use and water-use efficiency of coppice and seedling Eucalyptus globulus Labill.: a comparison of stand-scale water balance components

• Published in: Plant and soil 2012-01, Vol.350 (1-2), p.221-235
• Main Authors: Drake, Paul L., Mendham, Daniel S., White, Don A., Ogden, Gary N., Dell, Bernard
• Format: Article
• Language: English
• Subjects: Age; Agricultural and forest climatology and meteorology. Irrigation. Drainage; Agricultural and forest meteorology; Agronomy. Soil science and plant productions; Animal, plant and microbial ecology; Australia; Biological and medical sciences; Biomass; Biomedical and Life Sciences; Botanical research; Comparative studies; Coppicing; Ecology; Environmental aspects; Eucalyptus; Eucalyptus globulus; Evaporation; Forest canopy; Fundamental and applied biological sciences. Psychology; General agronomy. Plant production; Interception; Life Sciences; Plant Physiology; Plant Sciences; Plant-water relationships; Plantations; Rain; Regular Article; Rotation; SAP protein; Seasonal variations; Seedlings; Seeds; Soil; Soil science; Soil Science & Conservation; Soil-plant relationships. Soil fertility; Soil-plant relationships. Soil fertility. Fertilization. Amendments; Stemflow; Sulfur dioxide; Surface areas; Transpiration; Water; Water availability; Water balance; Water balance (Hydrology); Water balance and requirements. Evapotranspiration; Water use
• ISSN: 0032-079X; 1573-5036
• DOI: 10.1007/s11104-011-0897-5

Aims Growers of Eucalyptus globulus Labill. plantations can establish second and later rotations from coppice or by replanting with seedlings. At most locations where E. globulus is grown commercially, water availability is a major driver for productivity. Thus growers must consider which reestablishment technique will maximize productivity whilst sustaining site resources for subsequent rotations. In this study we aimed to compare the stand-scale water balance components of young coppice and seedling E. globulus. Methods A second rotation E. globulus coppice and seedling trial was monitored for two successive seasonal cycles. Coppice and seedling plots were instrumented with sap flow- and meteorological-sensors so that stand-scale water balance components could be estimated on a daily time step. Results Stand-scale transpiration rate (E) and rate of interception (E1) were larger in coppice compared to seedlings, but the rate of soil evaporation (ES) was lower. At approximately 2 years of age each coppice stump was reduced to a single dominant stem, a standard management practice for E. globulus growers, which reduced stem biomass by approximately 70% and caused E to fall to a value approximating that in seedlings. The cumulative transpiration of coppice was 425 mm greater than seedlings up to 34 months of age. Without the coppice reduction (down to one stem/stump), we estimate that the difference would have been much greater. The water-use efficiency of stem production (WUEstem) was greater in young coppice compared to seedlings but this benefit is likely to be offset by the loss of biomass (and thus transpired water) during coppice stem reduction. Conclusion Under the conditions of this study, which included reducing coppice to a single stem, reestablishment with seedling E. globulus resulted in a higher water-use efficiency of stem biomass production compared to coppice of a similar age.