| Digital technique study on Ginseng facilities production have theoretical significance and value on rational use of resources,increasing product yield and quality, and improving the ecological environment. It is supported by Science Foundation of Jilin Province"Research on development and utilization of the special resources——the digital technique research of Ginseng and Panax Quinquefoliu L. installation production"( Grant No.20040207-1). A Ginseng cultivation methods which uses agricultural facilities - greenhouse cultivation is established, which can meet the critical requirements of the production environment, and improve the quality of Ginseng. Ginseng can normally grow in no heating greenhouse in Northeast region because of the dormant characteristics, so this cultivation method save energy and reduce consumption.We Select shade tent and plastic greenhouse environment to compare studies on the growth respectively as experimental zone and reference areas, and concludes that the change of the small climate of experimental zone is conducive to the growth of Ginseng, the periods of seedling, flowering and fruiting was obviously sooner than the reference areas, but withered period extended. Therefore, the Ginseng which grows in experimental zone gets more solar energy than Ginseng grows in reference area to be about 40 days each year, and greenhouse Ginseng with 3 years old gets additional solar energy of 120 days than the Ginseng in reference area. We analyze the root weight and leaf length Ginseng for experimental zone and reference area, and the difference of the leaf length and root weight is notable because the double-tail t-test whose significant probability is less than 0.01. With stem height, leaf length, root weight as dependent variable and the environment temperature, humidity, soil temperature as variables, we analyze the table and get the relationship of values. From the crosstab diagonal table we conclude that for "the environment temperature and stem height and leaf length ","soil temperature and root weight" the frequency on the diagonal is greater than the expected value. From the chi-square test table we conclude that only " the environment temperature and stem height and leaf length "," soil temperature and root weight "can get across the Linear-by-Linear Association. Conclusion that we get the stem height, leaf length is closely related to environmental temperature, and the root weight is closely related to soil temperature in the Ginseng growth process, meanwhile, higher the temperature, the faster Ginseng growth in an appropriate extent. For example, about 20 days in Ginseng seedling, the daily average temperature of experimental zone is 7.4℃higher than that of reference area, the highest temperature reach up to 10.95℃; Soil temperature change was even more apparent, the daily average soil temperature of experimental zone is 9.2℃higher than that of the reference area, the highest temperature is 13.5℃. There are three changes stages: slow→fast→slow for the accumulation of Ginseng root weight in the whole growth period. Because of the different environmental conditions in two regions, Ginseng growing in the two zones are different, the amended model of root weight is a=1,c=46.791,b1=-5.988,b2=-1.558It is known that proper regulation to the environmental temperature and soil temperature of Ginseng growth, Ginseng stems,and leaves can grow fast and the root weight can increase, especially for three to four year Ginseng, and the growth period can be extended through the facilities cultivated , and the yield and quality of Ginseng products can be improved. The regulation of temperature in the greenhouse environment is practicable, therefore, the Ginseng cultivation transplanted to the greenhouse not only environmental factors can be adjusted so that the growth environment is better, buy also an alternative way is proved by which deforestation is avoided. The greenhouse micro-climate environment is a very complex system, which is restricted by a number of factors and conditions: material and energy transmission in greenhouse, the transmission of solar radiation and distribution , energy exchange in the crop growth process ,and soil heat conduction can affect the greenhouse environment. solar radiation is the main source in greenhouse, and which makes the indoor temperature change significantly depending on the weather conditions. At sunny weather, the temperature increases significantly, but at cloudy weather, the temperature increases little. Minimum temperature appeared after open grass tomakomai, the temperature rose rapidly in the morning, a maximum temperature appears at 13:00-14:00 in the afternoon. Because of the apparent effect of the heat preservation temperature of the greenhouse an night declines slow; Soil temperature has a cyclical day change and year change as air temperature, but the change amplitude of soil temperature is less than that of air temperature. The time of the highest temperature and lowest temperature is later than that of the ambient temperature.Under the same environmental conditions, the internal temperature of green- house soil bed without crops covered is high relatively, and temperature difference between top and bottom is larger. Because of the shelter effect of the Ginseng canopy, the soil bed heat was relatively less, and the amplitude of temperature rising is lower than that of bare soil.The influences of Ginseng canopy covering degree in greenhouse is fully considered, and the calculation method of Ginseng canopy covering degree is discussed , the vegetation covering model is obtained at last.The equation clearly shows the relationship between the covering degree and time of the different life Ginseng in the process from transplanting to withering. Using this mathematical model to calculate the canopy covering degree, only needs two tests. One is fulfilled after Ginseng transplanting, the other is used when the vegetation fully forms, and the initial and maximum values of vegetation coverage degree is gotten, so the vegetation coverage degree is directly calculated in the whole growth process of the crops.A soil temperature equation of semi-infinite periodic non-steady thermal conductivity is established by heat transfer theory, and then the temperature distribution formula is got through the boundary conditions. By the soil temperature wave equation, the general change rules of soil temperature can be drawn as follows: If soil depth arithmetic progression increases, the amplitude of soil temperature decreases geometrically. And the time when highest temperature and lowest temperature arisen lags the ambient temperature with the increase of the soil depth. Because of the boundary conditions change cyclically, temperatures of all points in soil change at the same cyclical rule, and the cyclical fluctuations takes place according to a certain amplitude with time and location after achieving the periodic balance when the process undergoing a sufficient period of time . To thermal conductivity equation that is with non-steady, no heat, and constant physical properties, a discrete solution method is adopted by inner nodes. We obtain the temperature of respective time layer—and the equation of boundary nodes— through the finite difference method according to the boundary conditions and the initial temperature distribution. The calculated value of temperature of each node is made by using chasing method to solve "three-diagonal matrix".The 2006 environment temperature in the greenhouse is measured, and the maximum temperature, minimum temperature, and the average temperature is recorded , the simulation model of average temperature is obtained at last. The air temperature in the greenhouse is a harmonic function which changes around the average temperature above. And the soil temperature is a harmonic function with the same cycle of air temperature, less amplitude, and lagging phase. We test and calculate 0cm to 20cm soil temperature, and know the difference between the measured values and simulated values is less than 2℃, which means that the conclusion from the soil mathematical model and the simulation results is correct.The Greenhouse temperature and heat transfer simulation model provide a theoretical basis for simulation environmental temperature and soil temperature change, and set up the foundation for the greenhouse microclimate control and greenhouse intelligent control. At the same time, Ginseng cultivated in the greenhouse and numerical model for Ginseng are built for further research. The results can be effectively used to guide the overall construction of the greenhouse and the greenhouse microclimate regulation. It is beneficial to greenhouse climate control, so high quality, high yield, and low energy consumption of Ginseng can be achieved. The complete system of shade tent, plastic canopy, under forest cultivation, and greenhouse cultivation for Ginseng growth is formed.
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