Root biomass, root distribution and the fine-root growth dynamics of Quercus coccifera L. in the garrigue of southern France

✍ Scribed by Kummerow, Jochen ;Kummerow, Margarete ;Trabaud, Louis

• Publisher: Springer-Verlag
• Year: 1990
• Tongue: English
• Weight: 586 KB
• Volume: 87
• Category: Article
• ISSN: 1573-5052
• DOI: 10.1007/bf00045653

✦ Synopsis

Quercus coccifera L., the characteristic scrub oak of the garrigue, covers more than 100,000 ha in southem France alone. Precipitation in this area averages 900 mm/year and summer rains are not rare. A total belowground biomass of 7.2 kg/m 2, including rhizomes and lignotubers, was harvested. Roots were concentrated in the uppermost 50 cm of the soil. It was hypothesized that low winter temperatures inhibit active fine-root growth. This hypothesis was tested by means of fine-root extractions of soil samples from 0-50 cm depth from November 1987 to June 1988. Although the fine-root analysis could not be extended into late summer and fall, the data supported the hypothesis. Ratios of live/dead fine roots reached their minimum at 0.2-0.3 from December to April. They increased to 1.0-1.2 during late spring and early summer. Initiation of fine-root growth in early April was synchronous with bud break. Starch contents of roots, rhizomes, and lignotubers fluctuated from 4.3 ~o in January to 8.3 ~o in April. The starch stored in belowground organs of Q. coccifera in a closed canopy stand amounted to about 500 g/m 2 in April. This amount declined to 400 g with bud burst and fine-root growth initiation.