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Each requirement is to be listed under a ”section” heading, as there will be a one-to-one correspondence between requirements, design, proposed imple- mentation and testing. Requirements should not discuss technical software issues, but rather focus on model capability. To the extent possible, require- ments should be relatively independent of each other, thus allowing a clean design solution, implementation and testing plan.

Algorithmic Formulations

Design solution: New modules are added for new developments

Date last modified: 8/28/2015
Contributors: Qing Zhu

For each requirement, there is a design solution that is intended to meet that requirement. Design solutions can include detailed technical discussions of PDEs, algorithms, solvers and similar, as well as technical discussion of performance issues. In general, this section should steer away from a detailed discussion of low-level software issues such as variable declarations, interfaces and sequencing.

• Two competition algorithms are implemented
• Soil microbes outcompete plants
  UPmic = min(Nav, UPmic)
  UPplant = min(max(Nav - UPmic,0), UPplant)
  UPmic and UPplant are microbial decomposer and plant nutrient uptake rate. Nav is soil available nutrient pool size
• Plant-microbe competition is scaled by their functional traits (e.g., biomass density) through ECA formulation
  UPmic = VMAXmic * [Emic]*[Nav]/(KMmic + [Nav] + [Emic] + [Eplant]*KMmic/KMplant)
  UPplant = VMAXplant * [Eplant]*[Nav]/(KMplant + [Nav] + [Eplant] + [Emic]*KMplant/KMmic)
  VMAX and KM are kinetics parameters, Emic and Eplant are nutrient carrier enzyme abundance for decomposing microbes and plants
  
  
• Leaf level physiology: how does N/P limitation on GPP occur
• VCMAX = f(leafN, leafP); JMAX = f(leafN, leafP)
• VCMAX and JMAX are maximum carboxylation and electron transport rate for photosynthesis. Their relationships with leaf level N/P concentration are derived form TRY database.
  
  
• N2 fixation = f(carbon cost of root nitrogen uptake, carbon cost of N2 fixation, plant phosphorus status)
• N2 fixation occur only when roots are not able to acquire enough nitrogen. N2 fixation rate could be limited plant phosphorus shortage.
  
  
• Phosphatase activity = f(nitrogen cost, plant nitrogen status, plant phosphorus status)
• Phosphatase activity is nitrogen expensive. It occur only when the benefit is larger than the cost. 
  
  

 

Design and Implementation

Implementation: Offline test with MATLAB codes plus online test within ACME

Date last modified: 8/28/2015
Contributors: Qing Zhu

 

This section should detail the plan for implementing the design solution for requirement XXX. In general, this section is software-centric with a focus on software implementation. Pseudo code is appropriate in this section. Links to actual source code are appropriate. Project management items, such as svn branches, timelines and staffing are also appropriate. How do we typeset pseudo code?

• Initial prototype of the N-COM model has been developed and tested in MATLAB.
• The N-COM model is being integrated in ACME

 

Planned Verification and Unit Testing 

Verification and Unit Testing: Benchmarking

Date last modified: 8/28/2015 

Contributors: Qing Zhu

Planned Validation Testing 

Validation Testing: Model validate with global dataset

Date last modified: 8/28/2015 

Contributors: Qing Zhu

Planned Performance Testing 

Performance Testing: short-description-of-testing-here

Date last modified:8/28/2015
Contributors: Qing Zhu