Abstract The photosynthesis and productivity of Lemna gibba were studied with a view to its use in Controlled Ecological Life Support Systems (CELSS). Photosynthesis of L. gibba floating on the nutrient solution could be driven by light coming from either above or below. Light from below was about 75% as effective as from above when the stand was sparse, but much less so with dense stands. High rates of photosynthesis (ca. 800 ηmol CO2-g dry weight (DW)−1 s−1) were measured at 750 μmol m−2 s−1 PPF and 1500 μmol mol−1 CO2. This was attained at densities up to 660 g fresh weight (FW) · m−2 with young cultures. After a few days growth under these conditions, and at higher densities, the rate of photosynthesis dropped to less than 25% of the initial value. This drop was only partly alleviated by thinning the stand or by introducing a short dark period at high temperature (26°C). Despite the drop in the rate of photosynthesis, maximum yields were obtained in batch cultures grown under continuous light, constant temperature and high [CO2]. Plant protein content was less than reported for field grown Lemna. When the plants were harvested daily, maintaining a stand density of 600 g FW m−2, yields of 18 g DW · m−2 d−1 were obtained. The total dry weight of L. gibba included 40% soluble material (sugars and amino acids), 15% protein, 5% starch, 5% ash and 35% cellulose and other polymers. We conclude that a CELSS system could be designed around stacked, alternate layers of transparent Lemna trays and lamps. This would allow for 7 tiers per meter height. Based on present data from single layers, the yield of such a system is calculated to be 135 g DW· m−3 d−1 of a 100% edible, protein-rich food.


    Access

    Check access

    Check availability in my library

    Order at Subito €


    Export, share and cite



    Title :

    Carbon balance and productivity of Lemna gibba, a candidate plant for CELSS


    Contributors:
    Gale, J. (author) / Smernoff, D.T. (author) / Macler, B.A. (author) / MacElroy, R.D. (author)

    Published in:

    Publication date :

    1989-01-01


    Size :

    10 pages




    Type of media :

    Article (Journal)


    Type of material :

    Electronic Resource


    Language :

    English



    Carbon balance and productivity of Lemna gibba, a candidate plant for CELSS

    Gale, J. / Smernoff, D. T. / Macler, B. A. et al. | NTRS | 1989


    Nostoc sphaeroides Kützing, an excellent candidate producer for CELSS

    Hao, Zongjie / Li, Dunhai / Li, Yanhui et al. | Elsevier | 2011




    CELSS engineering parameters

    Drysdale, Alan / Sager, John / Wheeler, Ray et al. | NTRS | 1993