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311.
Summary Seasonal growth dynamics of the root and shoot systems of dominant shrubs of the Chilean matorral were studied. In some species root and shoot activity were synchronous, while in others production of fine roots was observed prior to bud burst and shoot elongation. Biomass production of new roots was significantly higher in spring than in autumn. Maximum biomass of dead roots was concomitant with the maximum amounts of litter under the canopy. 相似文献
312.
Since the establishment of abalone farming, there has been an increase in the demand for Macrocystis as a food source. Therefore, the pressure on natural stock has also augmented and the sustainability of the actual harvesting
practices has been questioned. In this article, an attempt to farm Macrocystis pyrifera by zoospores in northern Chile is described; initially under laboratory conditions and subsequently by cultivation in the
sea. The experiments were executed during 1 year and two different cultivation methodologies were used: a direct and an indirect
method. A maximum frond length of 175 cm was reached and 22 kg m−1of rope was produced after 120 to 150 days of cultivation in the sea. The algae grew under both methodologies, and no differences
in algal length and biomass were detected between the two cultivation systems. However, the direct culture method can be recommended
for productive and practical reasons. 相似文献