premise: a plant is a kind of organism sent2: organisms are a part of an environment sent3: if a living thing requires something then that something has a positive impact on that living thing sent4: harming something has a negative impact on / effect on that something sent5: an environment is a kind of ecosystem sent6: a plant / living thing requires nutrients to grow sent7: a living thing is an organism sent8: fallen trees are a kind of dead organism sent9: removing dead organisms from an ecosystem causes available nutrients to be removed from that ecosystem.
hypothesis: removing fallen trees harms an ecosystem by removing available nutrients