A tension zone is a transitional zone between two distinctive zones, the zones may be influenced by climatic factors,[1][2] and geological variation.[3] creating a floristic tension zone.[4] A marine tension zone may be affected by variables such as depth, climate or salinity.[5] In a tension zone there is the increased probability of hybridization between species of the separate zones and thus the tension zone may also be a hybrid zone.[6]
Historically tension zones were entirely natural in origin, however human activity has altered the tension zones in a variety of areas all over the world.[7]