Silverstone S, Nelson M, Alling A, Allen J P
Laboratory Biosphere Division, Biosphere Foundation, Santa Fe, NM 87508, USA.
Adv Space Res. 2005;35(9):1544-51. doi: 10.1016/j.asr.2005.06.008.
During the years 2002 and 2003, three closed system experiments were carried out in the "Laboratory Biosphere" facility located in Santa Fe, New Mexico. The program involved experimentation of "Hoyt" Soy Beans, (experiment #1) USU Apogee Wheat (experiment #2) and TU-82-155 sweet potato (experiment #3) using a 5.37 m2 soil planting bed which was 30 cm deep. The soil texture, 40% clay, 31% sand and 28% silt (a clay loam), was collected from an organic farm in New Mexico to avoid chemical residues. Soil management practices involved minimal tillage, mulching, returning crop residues to the soil after each experiment and increasing soil biota by introducing worms, soil bacteria and mycorrhizae fungi. High soil pH of the original soil appeared to be a factor affecting the first two experiments. Hence, between experiments #2 and #3, the top 15 cm of the soil was amended using a mix of peat moss, green sand, humates and pumice to improve soil texture, lower soil pH and increase nutrient availability. This resulted in lowering the initial pH of 8.0-6.7 at the start of experiment #3. At the end of the experiment, the pH was 7.6. Soil nitrogen and phosphorus has been adequate, but some chlorosis was evident in the first two experiments. Aphid infestation was the only crop pest problem during the three experiments and was handled using an introduction of Hyppodamia convergens. Experimentation showed there were environmental differences even in this 1200 cubic foot ecological system facility, such as temperature and humidity gradients because of ventilation and airflow patterns which resulted in consequent variations in plant growth and yield. Additional humidifiers were added to counteract low humidity and helped optimize conditions for the sweet potato experiment. The experience and information gained from these experiments are being applied to the future design of the Mars On Earth(R) facility (Silverstone et al., Development and research program for a soil-based bioregenerative agriculture system to feed a four person crew at a Mars base, Advances in Space Research 31(1) (2003) 69-75; Allen and Alling, The design approach for Mars On Earth(R), a biospheric closed system testing facility for long-term space habitation, American Institute of Aeronautics and Astronautics Inc., IAC-02-IAA.8.2.02, 2002).
在2002年和2003年期间，在位于新墨西哥州圣达菲的“实验室生物圈”设施中进行了三项封闭系统实验。该项目涉及对 “霍伊特” 大豆（实验#1）、犹他州立大学远地点小麦（实验#2）和TU - 82 - 155红薯（实验#3）进行实验，使用的是一个5.37平方米、深30厘米的土壤种植床。土壤质地为40% 的黏土、31% 的沙子和28% 的粉砂（黏壤土），取自新墨西哥州的一个有机农场，以避免化学残留。土壤管理措施包括最小耕作、覆盖、每次实验后将作物残茬返还土壤以及通过引入蚯蚓、土壤细菌和菌根真菌来增加土壤生物群。原始土壤的高pH值似乎是影响前两项实验的一个因素。因此，在实验#2和#3之间，对表层15厘米的土壤进行了改良，使用了泥炭藓、绿砂、腐殖酸盐和浮石的混合物，以改善土壤质地、降低土壤pH值并提高养分有效性。这使得实验#3开始时的初始pH值从8.0降至6.7。实验结束时，pH值为7.6。土壤中的氮和磷一直充足，但在前两项实验中出现了一些黄化现象。蚜虫侵害是这三项实验中唯一的作物害虫问题，通过引入多异瓢虫来处理。实验表明，即使在这个1200立方英尺的生态系统设施中也存在环境差异，例如由于通风和气流模式导致的温度和湿度梯度，这进而导致了植物生长和产量的变化。添加了额外的加湿器来抵消低湿度，并有助于优化红薯实验的条件。从这些实验中获得的经验和信息正在应用于未来“地球火星”设施的设计（西尔弗斯通等人，用于为火星基地的四人机组人员提供食物的基于土壤的生物再生农业系统的开发和研究项目，《空间研究进展》31(1) (2003) 69 - 75；艾伦和阿林，“地球火星”的设计方法，一个用于长期太空居住的生物圈封闭系统测试设施，美国航空航天学会，IAC - 02 - IAA.8.2.02，2002）。
