humus

小説を続けて読んだので今度はノンフィクションを読むことにしました。昆虫学者（entomologist）の書いた本で、タイトルはThe Creation。元キリスト教徒の著者が牧師に貴重な地球の生物を一緒に守りことをお願いをする形式で書かれていますが、もちろん牧師だけではなく人類全ての人に訴えている内容です。昆虫学者だけに取り上げている生物は小さな生物が多いようだ。
A suburban woodlot is obviously no longer a wilderness for mammals, birds, and trees. But it might be a "microwilderness" for small organisms. Many kinds of insects, mites, and other arthropods, mostly under ten millimeters in size, range freely there, their local domains untroubled by human hands, feet, or tools. Luckily, microwildernesses are not a trivial part of wild Nature. Quite the opposite: each cubic meter of soil and humus within it is a world swarming with hundreds of thousands of such creatures, representing hundreds of pecies.
"soil and humus" の "humus" は初めて目にする単語なので辞書を引きます。
・Collins Dictionary: a dark brown or black colloidal mass of partially decomposed organic matter in the soil. It improves the fertility and water retention of the soil and is therefore important for plant growth.: The ideal soil for parsley is rich in humus, deeply dug and friable to facilitate root penetration and development.
・Macmillan Dictionary: partially decomposed organic matter; the organic component of soil
区民農園を借りて野菜作りをしているので腐葉土の重要性は良く知っています。