A preliminary account of aerial plant biomass in fynbos communities of the Mediterranean-type climate zone of the Cape Province

• Main Author: F. J. Kruger
• Format: Article
• Language: English
• Published: South African National Biodiversity Institut 1977-11-01
• Series: Bothalia: African Biodiversity & Conservation
• Online Access: https://abcjournal.org/index.php/abc/article/view/1421
• ISSN: 0006-8241; 2311-9284

Aerial plant biomass has been sampled by harvesting on several sites in fynbos communities of the south­western Cape Province. Biomass in stands of about two years old ranged from about 2 200 kg per ha to about 7 500 kg per ha. Mature stands comprised about 11 000 to 15 000 kg per ha in heaths and 15 000 to 26 000 kg per ha in sclerophyllous scrub. The data indicate a maximum annual growth rate of 1 000 to 4 000 kg per ha early in the development of a stand, but growth rates appear to decline rapidly as communities age. Young stands are dominated by hemicryptophytes, which comprise about 2 000 to  6  000 kg per ha, or about 60 to 75 per cent of the biomass in stands of about four years old. Shrubs become prominent later, but the hemicryptophytes persist. The data indicate that the biomass, growth rates and the shape of the growth curves of fynbos communities are on the whole similar to those of analogous vegetation in other zones of mediterranean type climate. However, there are important structural differences in that analogues of the northern hemisphere (garrigue, chaparral) do not have a significant component of persistent hemicrytophytes. Although Australian heath communities do have this feature, the hemicryptophytes are not as prominent as in fynbos.