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Study On Soil Physicochemical Environment And Growth Model Of Ginseng

Posted on:2008-06-07Degree:DoctorType:Dissertation
Country:ChinaCandidate:L M ChenFull Text:PDF
GTID:1103360212997847Subject:Agricultural mechanization project
Abstract/Summary:PDF Full Text Request
Following development of the special resources, digital technique study on production of ginseng by installations is important and practical to make use of the resources, raise the ginseng yield, lower the production cost and improve the ecosystem environment. Decision analysis, probability of statistics and mathematical simulation were used for abstract description of various environment factors and its interactions and mutual check of ginseng growth. The model database system of ginseng, such as crop growth model, fertilization model were perfected and established. The model database system of ginseng is important to integrate intelligent decision-making system .In order to develop the physics and the chemistry environmental characteristics of ginseng bed soil ,fractal dimension characteristics and fertility characteristic were systematically analyzed, turned the method of description to the fertility fixed amount of ginseng soil, fertilization model , fertilization effect model and growth model of ginseng were established in this work , which is projects supported by Science Foundation of Jilin Province"Research on development of the special resources——the digital technique research of ginseng and American ginseng installation production"( Grant No.20040207-1) and the Doctoral Program Foundation of State Education Ministry of China.The results obtained in this work have provided a new date and models for integration intelligent decision system of ginseng.By studying physicochemical environment of ginseng bed soil, the influence between fertility characteristic and ginseng yield, quality were found. The study was to sum up soil condition for the ginseng's high produce and superior quality, to provide the theories reference for realizing our ginseng superior quality high product, to provide science basis for sustainable development of ginseng industry. Study showed that the particle composition of ginseng bed soil was regarded the physics sand particle (>0.01 mm) as principal particle, about having 50% to 65%, soil texture belongs to sandy soil. The percentage of dry glomerate particle, wet glomerate particle, water stable aggregate, micro-aggregates in the ginseng bed soil were measured and computed. Rupture structure ratio of the ginseng bed soil was calculated. The Dark-brown soil rupture structure ratio (average for 40.93%) of the old bed soil that three years living was higher than new bed soil (average for 32.98%)7.96%, the result because of the depletion of organic matter and the leaching loss of eutrophic caused macroaggregate to be defeated and dispersed during planting ginseng, so as to make the structure form of the old bed soil lowered obviously then new bed soil. This was the main reason which physical form of the old bed soil get overall worsen.The total porosity of the bed soil was 56.92% to 73.52% generally, which can satisfy the request of pore space in the ginseng cultivation process. Index of the ginseng growth to pore space far high in general farm crop. The experiment showed that the pore space of the old bed soil became bad, especially the air pore space (non- capillary pore). The bulk density of soil in 0.85 g/cm3 and soil water content 30% or so were fitted to ginseng growth. The water retention property of ginseng bed soil is another important condition to guarantee the growth with high produce ,study showed that water-holding capacity of the bed soil express obviously difference below 30 kpa moisture suction within the scope of 0~80 kpa moisture suction .But above the 30 kpa, especially above the 60 kpa, then the difference was very tiny. And usually water-holding capacity in a first floor was higher then in surface layer. The Albic Soil is the ginseng bed soil, the organic matter, cation exchange capacity and quick-acting nitrogen, phosphorus, potassium were measured, the experiment showed that distribute of regulation was similar . The results showed that we should pay attention to the improvement of 0-20cm layer soil fertility, that should notice the improvement of the 20-40cm layer soil fertility, thus lower the disadvantageous factor to the restrict of the ginseng yield. The pH-value of the first floor soil had a trend of acidulation, which should notice, increase use of organic fertilizer, in order to prevent acidulation from influencing the yield and the quality of ginseng.Fractal dimensions of particle surface were 2.890-2.963 in Radix Ginseng Albic Soil. Decide numerical of fractal dimensions of particle surface first is to clay content, is a content of silt the next in order, the sand grain via affecting the former two content of how much indirectly influence numerical of fractal dimensions of particle surface. Statistic analysis indicated that fractal dimensions were in very significant positive correlation with the contents of bulk density, porosity and confined water(moisture suction >60 kpa), and in highly significant negative correlation with >0.25㎜ aggregate. Fractal dimensions were in the partial correlation with the contents of bulk density and content of organic matter (reply the related coefficient as R=0.7829*). The bulk density of soil in highly significant negative correlation with the organic matter content ( R=0.666*), the results showed that bulk density of soil lowered obviously along with the soil increment of the organic matter content. Study showed that fractal dimensions can reflect the fertility level of the soil physics goodly, and can be one index of measure the ginseng fertility of Radix Ginseng Albic Soil.By studying the only factor analysis of affecting the fertility of soil, it was known that in the process of the improvement of the ginseng soil fertility, not only to guarantee the full supply of the soil nutrient, but also notice the improvement of the soil structure, to make the center modulator of this soil adequately exert the function which regulated fertility development, guaranteeing the ginseng growth and attaining the superior quality, high cultivation purpose that produce. Through the experiment, the accuracy of analysis method of the integrated evaluation of soil fertility numerical value factor was verified, the scientific research method was provided for the nutrient diagnosis of the soil and the ginseng. From the contribution analysis of index sign of single-item soil fertility, the organic matter and the nutrient contents of the marking soil fertility carbon condition, which are quick-acting nitrogen, phosphorus got a goal the percentage higher. This also explained that the soil structure had the decisive function in deciding the soil productivity, because it affected the water, air and heat regime in the field heavily. The size, quantity and stabilities of the soil water stable aggregate, deciding the size of the soil pore and the stability of the structures, was an important index of the permeability, the corrosion-resistant and soil fertility that affected the soil. By means of affecting form of soil nutrient, its availability and the soil microorganism activities, the soil PH value can affect the plant to the absorption of the nutrient.By field plot test and statistic analysis, with the method of rotation experimental design, regression model of ginseng fertilizer efficiency was established. Main effect and unifactorial effect analysis of were carried on affecting four factors of the ginseng yield, the effect diagram of the factor and yield was got. As a result express that in nitrogen, phosphorus, potassium, compound micronutrient fertilizer, the increasing production efficiency in order was nitrogen fertilizer > potassium fertilizer> compound micronutrient fertilizer > potassium fertilizer. Three kinds of fertilizer was used alone, the excessive dosage made the production drop in crop yield and can't acquire the anticipant result. So not as to reflect the efficiency of the diminishing returns that applied more fertilizer, which elucidated that applying fertilizer excessive would cause the total biological yield of ginseng to descend. To assure some two factors of nitrogen, phosphorus , potassium, compound micronutrient fertilizer in 0 levels, it would get the sub- model of the other 2 factors and yield respectively, to put the -2~+2 level in each models of equation 5-3,it would get the interaction effect of the four factors. Further drawing response curved surface with the yield numerical value. According to the theory of the diverse function pole, the calculation responded to the four factors'level when reaching the maximum of the ginseng yield in the response curved surface. Then continue to use the method of declining dimension with mathematical model of yield, which was to put the single factor experiment the regression sub- model to derive the number to get its marginal production model, which was used to draw the four factors'marginal production curve. It could be known the relation between the fertilizer dosage and yield from the curve.The yield function of ginseng fertilization on trial was nonlinear function, which obtain the optimizing solution through statistics analysis. The highest yield could be acquired under the condition of this experiment ymax=895.55 g/m2, the optimum scheme of fertilization was x1=0.14(amount to urea 26.75 g/m2); X2=0.20(amount to superphosphate fertilizer 55.00 g/m2); X3=0.19(amount to potassium sulphate 43.80 g/m2); X4=0.18(amount to compound micronutrient fertilizer 8.18 g/m2). Based on the fertilizer profit model, the optimum scheme of fertilization was obtained when profit reached net-return maximization: x1=0.408(amount to urea 26.74 g/m2); X2=0.200(amount to superphosphate fertilizer 55.00 g/m2); X3=0.184(amount to potassium sulphate 43.69 g/m2); X4=0.347(amount to compound micronutrient fertilizer 8.8 g/m2). The optimum fertilization scheme of highest yield is quite near to net-return maximization, so the highest yield application rate could be as the dose rate recommendation. It elucidated the phenomenon that increased production but not to increase harvest for the improvement of ginseng application, didn't exit. Therefore when carrying on metrology fertilizer, the highest yield dose rate could be adopt.The yearly accumulation variety regulation of ginseng's backlog matched S-form natural growth curve, which was close by the variety regulation of namely with the logistic increase curve. The accumulation variety regulation of ginseng's backlog, at whole living long-term variety regulations to all present three stages clearly. In the first year and the second years, the weight increased slowly. In the third years and the fourth years, the increment of the root weight was to become rapid growth, and it began rapid growth at the growth anaphase of the fourth years. In the fifth years and the sixth years, the increment of the root weight turn was slow. And in the fifth years, the growth speed is the fastest. The best model that fitted to ginseng growth is y = 1 +e47.64 .4719+11.558t ,which was got by adopting F value of regression equation and correlation coefficient R, making use of the experiment data to snap four kinds of equation of s-form natural growth curve . The equation reflected exactly the relation between the ginseng root weight and growth time limit, which also reflected the yearly variation regulation of ginseng's root weight accumulation exactly.
Keywords/Search Tags:Ginseng, Bed soil, Physicochemical environment, Fractal dimensions Integrated evaluation, fertilizer model, Logistic model, Growth regulation
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