Primary exploration of Ecological Field of annual weed patch

摘要

The concept of Wu’s Ecological Field (EF) for individual was extended to weed patch (colony) in this article. Using the CA simulation tool (Wang et al, 2003), the relationship between EF of a small weed patch with only one cell and its density (state) as well as the one between EF of weed in a patch with an initial state (vi, i=3, 6, 12) and its size were simulated. The simulation results showed that (1) the larger initial state value (higher density) of a cell is, the more intensive its EF is; (2) the bigger patch size with the same initial state is, the more intensive its EF is. This implies that in agricultural practice, it is more difficult to control weed patch with higher EF, or it needs larger controlling force (or more herbicide) to control weed patch with higher density or larger size. At the same time, the results answered, in EFT, the question: “why is annual weed distribution often in patch?”.