People
| Post Doctoral Fellow | René van Hout |
| Graduate Student | Weihong Zhu |
| Undergraduate Student | Brent Golden |
| Project Supervisors | Prof. Joseph Katz |
| Design and Technical Support | Yury Ronzhes Stephen King |
Outline
In the Bio-Complexity project, advanced instrumentation required to understand and predict the emission and transport of “Primary Biological Aerosol Particles” (PBAP) into the atmosphere is developed and tested both in the laboratory and in the field. The ability to measure biological aerosols over a range of scales is essential for understanding their impact on the environment. PBAPs include pollen, viruses, bacteria, fungal spores, and allergens from animals, which affect the health of humans, animals and plants. For example, knowledge on the dispersal of disease-producing fungal spores is necessary to establish management strategies to protect agricultural crops.
The transport of pollen has always been of interest due to the decreasing probability of cross-fertilization and consequent decreasing genetic diversity between vegetation patches in fragmented landscapes. More recently, the news media has focused on the lack of knowledge about the transport distance of genetically altered pollen, which can contaminate natural populations. To understand the processes involved in transporting pollen (or any PBAP), it is crucial to develop the instrumentation along with the computational modeling framework that can be used to predict the emission and transport of these particles under different atmospheric conditions. In this study we will focus on pollen due, in part, to the pressing societal needs to understand pollen transport, and also because it offers the advantage that pollen from different plants differ morphologically allowing its source to be identified and its pathways identified. The instrumentation and associated modeling techniques could be applied in the future to any biological aerosols.
We will integrate information on the movement of pollen across multiple scales of time and space spanning the motion of pollen (microns), its release from the plant anther (centimeters), its entrainment into the atmospheric boundary layer (meters), up to its dispersion across field scales (kilometers). At the pollen scale, small wind tunnel studies, microscopic techniques and Direct Numerical Simulation (DNS) to quantify the dynamics of pollen motion are used. At the anther and plant scales,particle tracking using high-speed digital photography, particle image velocimetry (PIV) and holography, along with DNS and high resolution Large Eddy Simulation (LES) are employed. In the field a combination of the instrumentation developed in the laboratory (PIV, holography) and micrometeorological instrumentation, pollen collectors, and LIDAR (light detection and ranging) are applied at sites around the Chesapeake Bay. The field experiments will be used to understand the transport of the pollen grains and test and refine LES models for pollen transport at field scales.
The combined experimental and computational framework and the novel deployment of the proposed ensemble of instruments will lead to better predictions and basic understanding of the transport and fate of biological aerosols in the turbulent atmosphere.
Experimental Setups
Field Experiment 2003
Particle Couette Facility
Windtunnel Setup
Pollen Density: Digital Holography
Publications
Zhu, W., van Hout, R., Katz, J., (2007) PIV measurements in the atmospheric boundary layer within and above a mature corn canopy. Part B: Quadrant-Hole analysis. Journal of the Atmospheric Sciences.
van Hout, R., Zhu, W., Luznik, L., Katz, J., Kleissl, J., Parlange, M., (2007) PIV measurements in the atmospheric boundary layer within and above a mature corn canopy. Part A: Statistics and small scale isotropy. Journal of the Atmospheric Sciences.
van Hout, R., Katz, J., (2004) A method for measuring the density of irregularly shaped biological aerosols such as pollen. Journal of Aerosol Science. 35(11) 1369-1384.
van Hout, R., Smith, J., Chamecki, M., Higgins, C., Katz, J., Parlange, M., Brush, G., (2005) The circadian rhythm of corn ( Zea mays L. ) pollen dispersal into the atmosphere and its relation with local meteorological conditions. Biocomplexity in the environment Awardees 2005 Meeting, March 20-23, Washington DC, USA.
van Hout, Zhu, W., Katz, J., (2005) Experimental study at increasing scales of the characteristics of corn ( Zea Mays L. ) pollen dispersal into the atmosphere. Biocomplexity in the environment Awardees 2005 Meeting, March 20-23, Washington DC, USA.
van Hout, R., Zhu, W., Luznik, L., Katz, J., (2004) PIV measurements of atmospheric turbulence above and within a corn canopy. Presented at the APS Division of Fluid Dynamics 57th Annual Meeting , 21-23 November, Seattle, WA, USA.
Yue, W., Parlange, M. B., Meneveau, C., Zhu, W., Van Hout, R., & Katz, M. J. (2004). Numerical investigation of turbulence structures within and above acorn canopy using large eddy simulation. AMS meeting, 16th Symposium on Boundary Layers and Turbulence (pp. 483). [9.7] 9-13 August, Portland, ME, USA.
Zhu, W., Luznik, L., van Hout, R., Katz, J., (2004) PIV measurements of atmospheric turbulence above and within a corn canopy. AMS meeting, 16th Symposium on Boundary Layers and Turbulence, 9-13 August, Portland, ME, USA.
van Hout, R., Katz, J., (2003) A method for measuring the density of irregularly shaped particles such as pollen. AGU 2003 Fall meeting, 8-12 December, Moscone Center West, San Francisco.
Zhu, W., Luznik, L., van Hout, R., Katz, J., (2003) PIV measurements of atmospheric turbulence and pollen dispersal above a corn canopy. AGU 2003 Fall meeting, 8-12 December, Moscone Center West, San Francisco.