Intraspecific regulation of populations of the clonal herb, Cyperus esculentus.
Abstract
The influence of competition on ramet populations of C. esculentus was studied experimentally at a site near Harare, Zimbabwe. A range of ramet densities was achieved by planting on to 10 000 tubers/m2. Ramet growth was most prolific from Oct. to Apr. the main rainy season, with ramets dying off during May and June as soils dried. Production of new ramets and tubers was density-dependent. Ramet production responded to competition in a compensatory manner but tuber production was mainly restricted at high densities. Ramet mortality was more affected by climatic conditions than by competition. Biomass peaked within a few months of growth. This was shown by the slope of approx. -1 of the log10/log10 regression of biomass production per planted ramet on planted ramet density. The relationship between log10 wt and log10 density for several populations of living ramets approached and briefly followed the -3/2 self-thinning line until dry and cooler weather increased ramet deaths.