Isaac Madsen

Isaac Madsen
  • PhD Student
  • Washington State University
  • Crop and Soil Sciences

Advisor: 

Bill Pan

Thesis or Dissertation Citation: 

Madsen, J. 2017. Nitrogen-plant-soil interactions at the root-rhizosphere, cropping system, and national scales. Washington State University PhD Dissertation.

Research Focus: 

Nitrogen loss from irrigated cropping systems

Research Abstract: 

The transport and transformation of N at all scales is of paramount importance to humans. Not only is N crucial for our survival, being a central building block in protein, but N can also be toxic when found in high concentrations in the wrong locations. This work focuses on the importance of the place of N at three distinct scales. 1.) At the seedling root system scale we examined the effects of the concentration of N on causing symptoms of root toxicity, and found increasing ammoniacal-N to increase the symptoms of toxicity to roots. 2.) At the field scale, cover cropping and reduced tillage where assessed for their potential to decrease soil NO3- leaching and increase of N exportation efficiency. 3.) At the national scale a research project database was used to assess the amount of research that has gone into the development of best management practices.

Biography: 

Isaac Madsen is originally from Portland, OR. Although not originally from an agricultural background he has a life long interest in agriculture, food systems, as well as basic plant and soil science. He is passionate about the rhizosphere and producing videos of roots growing.

Publications and Presentations: 

Pan, W., Madesn, I., Bolton, R., Graves, L., Sistrunk, T. 2016. Ammonia/ammonium toxicity root symptoms induced by inorganice and organic fertilizers and placement. Agronomy Journal. 108(6): 21875-2492.