The Research On The Ecological Field Behavior Of Ulmus Pumila Individual

Interactions between organisms or organisms and environment are the basic problems of ecology. Ecological field theory (EFT) is a basic theory of physical ecology derived from the thought of field theory concepts in physics. EFT studies interactions among neighboring plants located at a distance from each other using modes of deductive thought and relative strict quantitative, synthetic and intuitionistic model. Establishing reasonable ecological field model is the key problem of EFT. This research made further elucidation to the concepts of some ecological field characteristic parameters, and gave the method of deducing lower limit of plant ecological adaptation and distinguishing the positive field source, negative field source and zero field source. Author improved models of ecological field intensity and ecological potential and the influence domain of field source. This paper established the subsection model of ecological potential by accepting the computing method of electric potential in electrostatic field, and then gave the computing method on ecological potential field gradient. It expounded the materiality of plant ecological field and establishes some models about the materiality. In order to reveal the interaction relationship between Ulmus pumila and Securinega suffraticosa and between two U. pumila individuals, this research made study on the ecological field behavior of U. pumila individual by using ecological field theory and the improved models, such as ecological field intensity, influence domain of ecological field, lower limit of plant ecological adaptation, field source, ecological potential and ecological potential gradient. This paper measured mainly effecting plant growing parameter: net photosynthetic rate, photosynthesis available radiation, soil water content and soil total nitrogen. The results of U. pumila and S. suffraticosa' interaction were summarized as following: within the ecological field domain of U. pumila individual, 1) the ecological field intensity was the maximum at the root of U. pumila, then reduced gradually as the distance to the field source increasing; 2) the influence domain of U. pumila individual reached the maximum value in the surface soil, and declined as the soil depth increased. It reached the minimum value in the forth soil layer (30-40cm), then increased lightly again despite the deeper soil; 3) the lower limit of plant ecological adaptation was r_3olwer=0.0241, x_lower = 1.93m; 4) U. pumila was a positive field source; 5) the result of the first model of ecological potential was that the ecological potential was the minimum at the root of U. pumila, and became bigger as the distance to the field source increasing, then decreased at last; the result of the second model of ecological potential was less than zero near the U. pumila, as the distance increasing to field source ecological potential became positive and then negative again; 6) the ecological potential gradient was greater near the U. pumila than the other ecological field region, then decreased as the distance increasing to the field source. The problem of the interaction between two U. pumila individuals each other was complicated, the results indicated: 1) if there was an overlap region, the maximum of ecological field intensity in the whole ecological field region was decided by the size of overlap region. If the distance of two U. pumila individuals was shorter than 4m ( l ≤ 4m), the strongest interaction and competition relationship existed. The maximum of ecological field intensity didn't appear at the field source but other point in the field region. If 4m < l<8m, there existed interactions and competition relationship between two U. pumila individuals, and the maximum of ecological field intensity appeared at the field source; 2) if there was no overlap region, l ≥ 8m, the maximum of ecological field intensity appeared at the field source, and there was no interaction between two U. pumila individuals. This research considered that the ecological field behavior of U. pumila individu...