A new type of spiral wave caused by the pitchfork bifurcation of a limit cycle is reported, which may exist in ecosystems containing two (or more) species that are not symbiotic. The dynamical behavior of the spiral wave is explained by a superposition principle of disturbance intensity vectors in oscillatory media. This type of spiral wave is characterized by a slow-moving line-defect that passes through the spiral center. The line-defect disturbs the local phase waves, whose disturbance can be superposed with the disturbance coming from the spiral core. This superposition principle of disturbance intensity vectors provides a new theory and method for studying the pattern formation in oscillation media. On the one hand, our findings shed light on the dynamics of the pattern formation; on the other, we predict a type of spiral wave which has not been found in nature or laboratories to date, and provide directions and guidances for ecological researches about ecosystems containing two (or more) species that are not symbiotic.

据报道，由极限循环的干草叉分叉引起的新型螺旋波可能存在于包含两个（或多个）非共生物种的生态系统中。螺旋波的动力学行为由振荡介质中干扰强度矢量的叠加原理解释。这种螺旋波的特征是穿过螺旋中心的缓慢移动的线缺陷。线缺陷会干扰局部相波，这些相波的干扰可以与来自螺旋铁心的干扰相叠加。扰动强度矢量的这种叠加原理为研究振动介质中的波型形成提供了新的理论和方法。一方面，我们的发现揭示了图案形成的动力学。在另一，