ecotone
n.— «The Skagit Valley is hailed as a unique ecotone, an area of 1,000 year-old forests where two climatic zones overlap. As a result, plant and animal hybrids are common, all of which would be wiped out by the flooding.» —“Seattle suggests deal with B.C. over flooding of Skagit Valley” by Ian Mulgrew Globe and Mail (Toronto, Can.) Feb. 16, 1982. (source: Double-Tongued Dictionary)
Further reading
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