A class of nonlinear two species competition singularly perturbed initial-boundary-value problems in a reaction-diffusion system in biomathematics was studies using the modern method of differential equation.

This paper also deals with the design principle,value evaluation,standard system,utilization of withered tree landscape species competition and contrariety between protection and utilization.

The results showed that at the equilibrium, the coexistence condition of population competition is migratory ability and competition ability take on exponential negative correlation, the outcome of competition makes the superior and inferior sequence changed, the exclusion and coexistence of species competition was affected by migratory ability and competition ability, the metapopulations which are excluded in local patches can exist in regional scale, that is escaping coexistence.

(4)The competitive and dispersal ability have a profound effect on the competing elimination and coexistence of species, the condition of species competition and coexistence is the competitive ability have a nonlinear minus correlation with dispersal power.

The results in this paper also show: the factors which affect population pattern are two aspects, one is biological characteristics of species, the other is intra and inter species competition caused by environmental conditions;

Using the adjacent interference model, this paper studied the inner and intra species competition intensity of main species in mountain forestry community of western Henan Province and the competition interference state of species and individual in the community.

2.) The natural distribution and occurrence of Isoetes sinensis plants in Mainland China are closely correlated with its habitat characteristics including water physical and chemistry characteristics, species competition and water level.

Based on field survey, the structure and distribution patterns of Rhododendron delavayi population are studied in the paper, the results show that the distribution pattern of Rhododendron delavayi populations is mainly aggregated pattern, but as ages increasing ,the intensive interspecies and between species competition make the individuals decrease and the distribution pattern become the random one .

Niche overlap among species causes species competition and exclusion among species,and niche separation among species causes species harmo nic coexistence.

In this paper, the nonautonomous three species competition system are considered, where all the parameters are time-dependent and asymptotically approach periodic function, respectively. Sufficient conditions are determined that global attractivity of a periodic solution.

In this paper, We investigate two species competition system with diffusion and time delay and functional response and impulsive effect By using the method coincidence degree theorem, Sufficient conditions are obtained for the existence of positive periodic solutions Moreover, some known results improved and generalized.

Second, previously separated populations come in contact and may adapt to mitigate inter-species competition.

Aggressive species competition by Typha latifolia in wetland systems on marl-derived soils may threaten the unique vegetation in these areas.

Since changes in nutrient availability as a result of management measures affect the outcomes of heathland succession and species competition, studies on this issue are important from both a nature conservation and management point of view.

Inter-species competition for applied nutrients may be managed by weed control in cultivated communities.

Significant intra-species competition appeared to occur between G.

Competition in ecological system can be simulated by certain math-physical models. The existence of limit cycles in the models shows the region of ecological equivalence. Therefore, searching the limit cycles and the limit cycle behaviors exhibited by the models is very important.According to limit cycle theorem with Rosenzweig-Mac Arthur equation on two species competition system, a computational method was used to select initial values. The results of numerical computations demonstrate the existence...

Competition in ecological system can be simulated by certain math-physical models. The existence of limit cycles in the models shows the region of ecological equivalence. Therefore, searching the limit cycles and the limit cycle behaviors exhibited by the models is very important.According to limit cycle theorem with Rosenzweig-Mac Arthur equation on two species competition system, a computational method was used to select initial values. The results of numerical computations demonstrate the existence of a limit cycle near initial point, which offers a possible explanation for certain regular population oscillations of the predator-prey system : The peak density of the predator and prey are Xmax = Y (1) max = 9l.4031, Y (2) max =77.3508, respectively; and the trough density of the predator and prey are Xmin = Y (1) min = 4.75×10-4, Y(2 )min = 1.7828, respectively. The period of oscillation =4.70

The relationships among the growth rate per unit area of leaves,transform ratio of photosynthesis products,photosynthesis ability of leaves and leaf density were fully analyised,and the model of in terspecific competition of plants for light was proposed in this paper.In the model the outcomes of two-,three-,and n-species competition was discussed.Based on the ability tolerating shading of plants and their relative height in community,the pattern partitioning light resource space in plant communities has...

The relationships among the growth rate per unit area of leaves,transform ratio of photosynthesis products,photosynthesis ability of leaves and leaf density were fully analyised,and the model of in terspecific competition of plants for light was proposed in this paper.In the model the outcomes of two-,three-,and n-species competition was discussed.Based on the ability tolerating shading of plants and their relative height in community,the pattern partitioning light resource space in plant communities has been recognized.

本文通过对单位叶面积生长率、光合产物转换、叶面光合能力和叶密度之间函数关系的分析,建立了植物种间光竞争的模型。在此基础上讨论了二个种、三个种及至 n 个种为光资源竞争的结局;根据各植物种由生活型决定的最大生长高度和耐遮荫能力这二个生态学特性,确立了植物群落中光资源空间划分的模式。

The red tide event of 11￣28, May in 1987 was caused by Eucampia zoodiacus, a coastal eurythermic phytoplanktou. Results from the field monitoring indicated that during the red tide occurrence the optimal temperature and salinity for the multiplication of the red tide organism were 20￣25℃ and 26￣28. During the red tide event cell densities in two peak values both reached 3 000×103ind. /din3. Organism number in horizonal distribution increased from the harbour mouth to the inner harbour. Average number of the...

The red tide event of 11￣28, May in 1987 was caused by Eucampia zoodiacus, a coastal eurythermic phytoplanktou. Results from the field monitoring indicated that during the red tide occurrence the optimal temperature and salinity for the multiplication of the red tide organism were 20￣25℃ and 26￣28. During the red tide event cell densities in two peak values both reached 3 000×103ind. /din3. Organism number in horizonal distribution increased from the harbour mouth to the inner harbour. Average number of the organism at the monitoring stations in the inner harbour was 2 930×103 md. /dm3 which was 3. 7 and 61 times higher than that at the two control monitoring stations. The organism number in vertical distribution apparently showed stepwise, day and night changes. Daily change of the phytoplankton number with spring and ebb tides exhibited a negative relativity.Major reasons for this red tide event included species competition of red tide organisms, sudden increment in water temperature in short time, sharp decrement in salinity by rainfall, water eutrophication, high contents of stimulating materials such as Fe and Mn, poor water exchange condition and stable synoptic condition, etc.High content of dissolved oxygen and high pH value was resulted from the photosythesis of a great quantity of the red tide organisms.