據一項於12 月 8 日發表在Science Advances雜誌上的研究的合著者、土壤生態學家Matthew Bowker表示，中國長城的土壤表麵覆蓋著一層由微小無根植物和微生物組成的“活皮”，即生物結皮，這是該遺產地持久力的來源。
According to a study published in Science Advances on Dec. 8th, soil ecologist Matthew Bowker, one of the study's co-authors, states that the soil surface of the Great Wall has a "living skin," meaning tiny plants without roots and microorganisms covering the soil. This is also known as a biological crust that preserves the long-standing cultural heritage.
