| On the basis of the review and the analysis for facilities industry, the position and the function of the facilities agricultural production for the development of the society in the future, and the special stratagem position of the facilities agricultural production for agricultural development in China are discussed in this thesis. A series experiments were carried out to examine four aspects of facilities agricultural ecosystem (the greenhouse), which are structure, performance, production and the growing model. The thesis suggested that there was of a practical importance for developing "moderate-scale greenhouse" in a period of next few year. For this reason, a new type greenhouse named unsymmetrical multi-span energy saving greenhouse (USMPESG) was designed, which was more suitable to the situation of Northern area in China. The performance and the related technology of this new type greenhouse were investigated during the year of 2000 to 2002. It was verified that the property of temperature and light in a greenhouse could be improved through the structure design. The structure and the function of a greenhouse were the consistent. Careful design and good design of a greenhouse could decrease construction cost and production cost effectively, and increase production efficiency in the meanwhile. The results of the thesis could be drawn as following:1. The frame of unsymmetrical multi-span energy saving greenhouse is that the greenhouse is seated on North and faced to South with east-west length, 3-5 spans with each span of 6-8 meters, and the total span is within 38 meters. The roof of transparent area was arch with unsymmetrical structure, and the light entering angle is calculated according to the formula a=23. 5+ (local latitude-40 ) × 0. 5 ± 1, but the minimal angle of the roof could not smaller than 22; the height of the posts are not equal between different rows for avoid shading between arches and the lowest post is 2.5 m high; North side is a brick wall for heat preservation. Surrounding of the greenhouse is designed with heat preservation structure. The heat preservation of the transparent roof is changed from outside into inside. The scale or whole area in this kind of greenhouse is 1600-3500 m2.2. The results of greenhouse performance could be concluded as following:(1) Increasing coming light using efficiency. In the main growing season (day length is longer than 10 h), the determination of the greenhouses property showed that light intensity in USMPESG (greenhouse 1) was close to solar greenhouse (Greenhouse 3), but increased 25.1% in average compared with normal multi-span greenhouse (greenhouse 2, namely east-west orientation andnorth-south length). This was mainly occurred in the morning. The highest light intensity was at noon about 12 o'clock, which might come up to 35,000-41,000 Lux in March. The variation of light intensity in the greenhouse was kept the same step as global radiation in outside. The highest light intensity in greenhouse 2, however, was occurred at 14 hour afternoon that was close to or a little bit higher than greenhouse 1. Higher light intensity in greenhouse 1 means that the new greenhouse type can have the effect of light use efficiency like solar greenhouse; and meanwhile the greenhouse can be used for modern commercial production due to its large scale area(2) There was no significant difference of light distribution in vertical and in horizontal direction in both greenhouse 1 and 2, especially at the height of 150cm (crop canopy) above ground level. This might be because of large room in these greenhouses and relative small back wall (north wall). However, there was a difference of light distribution in North-South direction in solar greenhouse (greenhouse 3), because of the shading of the back wall and the back roof that was opaque.(3) The variation of temperature had the same trends as radiation which indicated that the greenhouse is dependent on the solar energy so that structure design is very important. The night tem...
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