Tikhomirov A A, Ushakova S A, Gribovskaya I A, Tirranen L S, Manukovsky N S, Zolotukhin I G, Karnachuk R A, Gros J B, Lasseur Ch
Institute of Biophysics RAS SB, Akademgorodok, Krasnoyarsk, Russia.
Adv Space Res. 2003;31(7):1775-80. doi: 10.1016/s0273-1177(03)80020-0.
To increase the degree of closure of biological life support systems of a new generation, we used vermicomposting to involve inedible phytomass in the intra-system mass exchange. The resulting product was a soil-like substrate, which was quite suitable for growing plants (Manukovsky et al. 1996, 1997). However, the soil like substrate can be regarded as a candidate for inclusion in a system only after a comprehensive examination of its physical, chemical, and other characteristics. An important criterion is the ability of the soil-like substrate to supply the necessary mineral elements to the photosynthesizing component under the chosen cultivation conditions. Thus, the purpose of this work was to study the feasibility of enhancing the production activity of wheat and radish crops by varying the intensity of photosynthetically active radiation, without decreasing the harvest index. The increase of light intensity from 920 to 1150 micromoles m-2 s-1 decreased the intensity of apparent photosynthesis of the wheat crops and slightly increased the apparent photosynthesis of the radish crops The maximum total and grain productivity (kg/m2) of the wheat crops was attained at the irradiance of 920 micromoles m-2 s-1. Light intensity of 1150 micromoles m-2 s-1 decreased the productivity of wheat plants and had no significant effect on the productivity of the radish crops (kg/m2) as compared to 920 micromoles m-2 s-1. The qualitative and quantitative composition of microflora of the watering solution and substrate was determined by the condition of plants, developmental phase and light intensity. By the end of wheat growth under 1150 micromoles m-2 s-1 the numbers of bacteria of the coliform family and phytopathogenic bacteria in the watering solution and substrate were an order of magnitude larger than under other illumination conditions. The obtained data suggest that the cultivation of plants in a life support system on soil-like substrate from composts has a number of advantages over the cultivation on neutral substrates, which require continual replenishment of the plant nutrient solution from the system's store to complement the macro- and micro-elements. Yet, a number of problems arise, including those related to the controlling of the production activity of the plants by the intensity of photosynthetically active radiation. It is essential to understand why the intensity of production processes is limited at higher irradiation levels and to overcome the factors responsible for this, so that the soil-like substrate could have an even better chance in the competition for the best plant cultivation technology to be used in biological life support systems.
为提高新一代生物生命支持系统的封闭程度，我们采用蚯蚓堆肥法，使不可食用的植物生物质参与系统内的物质交换。所得产物是一种类似土壤的基质，非常适合种植植物（马努科夫斯基等人，1996年，1997年）。然而，只有在对其物理、化学和其他特性进行全面检查之后，这种类似土壤的基质才能被视为纳入系统的候选物。一个重要标准是类似土壤的基质在所选种植条件下为光合组件提供必要矿质元素的能力。因此，这项工作的目的是研究在不降低收获指数的情况下，通过改变光合有效辐射强度来提高小麦和萝卜作物生产活性的可行性。光强从920微摩尔·米-2·秒-1增加到1150微摩尔·米-2·秒-1，降低了小麦作物的表观光合作用强度，略微增加了萝卜作物的表观光合作用强度。小麦作物的最大总产量和籽粒产量（千克/平方米）在920微摩尔·米-2·秒-1的辐照度下达到。与920微摩尔·米-2·秒-1相比，1150微摩尔·米-2·秒-1的光强降低了小麦植株的生产力，对萝卜作物的生产力（千克/平方米）没有显著影响。浇水溶液和基质中微生物群落的定性和定量组成取决于植物状况、发育阶段和光强。在1150微摩尔·米-2·秒-1光照下小麦生长结束时，浇水溶液和基质中大肠菌群细菌和植物病原菌的数量比其他光照条件下高出一个数量级。所得数据表明，在由堆肥制成的类似土壤的基质上的生命支持系统中种植植物，比在需要从系统储存中不断补充植物营养液以补充大量和微量元素的中性基质上种植具有许多优势。然而，也出现了一些问题，包括与通过光合有效辐射强度控制植物生产活性相关的问题。必须了解为什么在较高辐照水平下生产过程强度受到限制，并克服造成这种情况的因素，以便类似土壤的基质在竞争用于生物生命支持系统的最佳植物种植技术时能有更好的机会。
