Short answers, pulled from the story.
British ecologist Arthur Tansley introduced the term ecosystem in a paper published in 1935. He asked his colleague Arthur Roy Clapham to create the new phrase to describe how organisms interact with their physical environment.
Primary succession occurs after major volcanic eruptions leave behind soils lacking plants animals or organic matter. Secondary succession happens following less severe disturbances like forest fires which allow for faster recovery of the system.
Decomposition releases nutrients back to the soil for reuse by plants and microbes while returning carbon dioxide to the atmosphere. Freeze-thaw cycles break apart protective layers on leaves and animal bodies to expose new surfaces for microbial colonization.
The assessment identified four major categories including provisioning regulating cultural and supporting services. Human activity has significantly reduced both resilience and biocapacity over the last fifty years.
The study began in 1963 to examine White Mountains in New Hampshire as a single watershed. Researchers documented depletion of soil cations especially calcium and discovered acid rain in North America in 1972.