(Solved): These skills will help you to understand various concepts and techniques in biogeochemistry. If you ...

These skills will help you to understand various concepts and techniques in biogeochemistry. If you have trouble with the assignment, look at the supplemental videos on Canvas. Show your work where relevant. To show your work, you may upload a picture or scan or type out your responses. 12 pts total, due Friday, Aug 26, 2022 at \( 1: 10 \mathrm{pm} \) 1. Conversions ( \( 1 \mathrm{pt} \) ea; 3 pts total) a. Convert: \( 4 \mathrm{mg} / \mathrm{L} \mathrm{O}_{2} \) to \( \mathrm{mM} \) b. Convert: \( 260 \mathrm{mg} \mathrm{C} / \mathrm{m}^{2} \) soil to \( \mathrm{kg} \mathrm{C} \) Chectare c. Convert: \( 5 \mathrm{Tg} \mathrm{N} / 150,000 \mathrm{~km}^{2} \) to \( \mathrm{g} \) N/hectare 2. Balancing reactions ( \( 1 \mathrm{pt} \mathrm{ea} ; 3 \) pts total) a. Balance: \( \mathrm{N}_{2}+\mathrm{H}_{2} \mathrm{O} \rightarrow \mathrm{NH}_{3}+\mathrm{O}_{2} \) b. Balance: \( \mathrm{SO}_{3}{ }^{2-} \rightarrow \mathrm{S}^{-2}+\mathrm{SO}_{4}^{-2} \) c. Balance: \( \mathrm{CH}_{3} \mathrm{COO}^{-}+\mathrm{SO}_{4}^{-2} \rightarrow \mathrm{HCO}_{3}^{-}+\mathrm{HS}^{-} \) 3. Size and Scale (1 pt ea; 2 pts total) a. What is the volume of a lake (assume half-sphere) with a diameter \( =40 \mathrm{~m} \) ? b. What is the volume of soil in a plot 3-m square to a depth of 1-m? 4. Putting pieces together ( \( 1 \mathrm{pt} \mathrm{ea} ; 2 \) total): a. Lake Michigan has \( 4,920 \mathrm{~km}^{3} \) of water with \( 0.25 \mathrm{mg} / \mathrm{L} \mathrm{NO}_{3}-\mathrm{N} \). How many \( \mathrm{kg} \) of \( \mathrm{NO}_{3}-\mathrm{N} \) are in the lake? b. Beaches along Puget Sound occasionally have \( E \). coli contamination high enough to pose a risk to human health. A beach advisory is issued if \( E \). coli contamination exceeds 104 cells/100 \( \mathrm{mL}_{\mathrm{a}} \) Assuming people stay within \( 50 \mathrm{~m} \) of the shore, and there are \( 2 \mathrm{~km} \) of beach with an average depth of \( 2.5 \mathrm{~m} \) of water, how many \( E \). coli are potentially present before the beach is closed? 5. Using Web of Science ( \( 1 \mathrm{pt} \) each, 2 pts total). Access Web of Science through the WSU Libraries web site. You will have to log in with your WSU netID and password. a. What is the most cited paper that comes up when you search "Nitrogen biogeochemistry"? b. Which is the most recently published paper that cites the following reference? Vitousek \& Howarth 1991. Nitrogen limitation on land an in the sea-How can it occur? Biogeochemistry 13:2 p. \( 87-115 \).