(2) Scientists use eddy-covariance tower to measure Net Ecosystem Exchange (NEE), which is a measure of CO₂ fuxes between the ecosystem and its surro ounding environments. Does NEE equal to GPP or NPP or NEP? Why? (6 pt)

6.請說明準地轉系統中有關Rossby number，AspectratoCoriolis parameter的核心假設為何? (5分)

(a)請說明什麼是”再分析(reanalysis)資料"(8分)

(b)請從再分析資料的特性、雨量站觀測的特性、以及此類強降水事件的特性等不同面向 說明圖2上下兩個時間序列有差異的可能原因。(12分)

(1) Please define GPP. NPP, NEP respectively. (9 pt)

(3) View the latitudinal distribution of the global NPP below. A is global average, B is land average, and C is ocean average. Different lines indicate different seasons as explained in the figure captions. Please describe the latitudinal distribution patterns for NPP for land (5 pt) and ocean (5 pt) respectively. You may have noticed that for both land and ocean NPP. there is a local minimum around 20-30 degree N/S. Do they have similar or different reasons? Please explain. (10 pt)

(4) Now compare the latitudinal patterns of carbon storage on land in the following figure. The areas above 0 on the y axis is carbon storage above ground, and the areas below 0 on the y axis is carbon storage below ground (or soil organic carbon SOC for diflerent depths shown in the figure caption). Summarize the similarity and differences between the two (5 pt), explain what proce cesses drive the similarities and differences (5 pt). How would we predict future changes in carbon storage under the direct influence of CO2 rise and global warming (5 pt)?The latitudinal patterns of terrestrial carbon stocks, both aboveground living plant biomass (green) [data from Gibbs et al. (114)] and soil carbon stocks (brown) [data from Hengl et al. (18)].

(a) (6 pts) Above the ground and near the surface layer, aerobic(有 氧) respiration is a major process. Please write the overall reaction for aerobic respiration and calculate AE°(w) (using CH2Oas the reactant).

(b)(10 pts) Below the surface (anoxic(缺氧)conditions), other respiration processes, such as denitrification, sulfate reduction, and methanogenesis, might become significant. Please write the overall reaction for denitrification and sulfate reduction, and calculate AE°(w), respectively.

(c) (12 pts) Given your listed rcactions above (in a&b), please estimate their Gibbs free energy yield per clectron (in the unit of kcal per electron), using △G0 = - zF△E°(w) (z is the number of electrons, F is Faraday's constant 23.06 1 kcal/volt). Compare their Gibbs free energy, and explain how this would control the oxidation/reduction sequence in the sediments with the observed profile shown in Figure A. 

(d)Nitrification is the biological oxidation of ammonium to nitrite, followed by the oxidation of nitrite to nitrate under aerobic conditions.  (i) (4 pts) Please write the nitrification net reaction with a reactant of amnonium and the final product as nitrate.  (ii) (8 pts) If global net primary productivity on land is g C/yr, and the average C/N ratio of plant biomass is 100, what is the upper limit (i.e., maximum estimate) of oxygen used every year in microbial nitrification?