Theoretical point of view My ongoing ecological research focuses on the impact of an environmental gradient (distance from the water body) on plant growth and species richness in the Paul Lake Provincial Park region. The basic theoretical framework of this study. In Paul Lake Provincial Park, we have observed significant gradient changes in environmental factors such as soil humidity, light intensity, and soil nutrients with increasing distance from the water body. These changes had a significant effect on plant growth and species distribution. To gain a deeper understanding of these ecological processes, we designed a series of experimental and quadrat surveys to quantify plant community characteristics across different environmental gradients. The theoretical basis of this experiment is the ecological niche theory and the gradient analysis methods. The niche theory holds that each species has its specific niche in an ecosystem, its location in a multidimensional resource space, and the distribution and abundance of species are influenced by the degree their niche matches with environmental resources. Gradient analysis method reveals the regularity of species distribution and community structure by studying the continuous changes of environmental factors in space. Different ecological environments, or distance, will have an impact on plants, and different species will have different living environments, leading to differences in species richness.