macroalgae

Survival and propagation of macrophyte species in the rocky intertidal zone is one of the wonders of physical ecology.  That plants have adapted to survive and thrive in such a harsh environment indicates the benefits of the ability to biomechanically evolve.  Survival under such conditions requires success at a number of stages including fertilization, arrival of the dispersive stage at the substrate (settlement), initial dynamical attachment and long-term stronger attachment.  These processes are little-understood for macroalgal species, particularly the arrival stage that leads to settlement of propagules.  Sebastien Delaux has just completed his PhD on this topic - extending Gerris gfs.sourceforge.net
to represent finite volume moving particles.

Taylor, David, Sebastien Delaux, Craig Stevens, Roger Nokes, and David Schiel 2008  Settlement rates of macroalgal algal propagules: Cross-species comparisons of settlement in a turbulent environment Limnol. Oceanogr. 55: 66-76.


aquaculture



New Zealand's dominant coastal aquaculture is shellfish     (with a growing focus on fin-fish production). Aquaculture of shellfish species is expanding in many countries.  Limitations on, and competition for, inshore water space is making offshore shellfish developments more attractive.  There are many hydrodynamic issues relating to the design and mechanics of shellfish longline structures in relation to the offshore marine environment.  Two main facets are explored:

(i) the effect of the flow (waves and currents) on the farm.
(ii) the reverse perspective of the impact of the farm on the flow.

Because these systems are relatively new, we examine similar systems both natural (kelp beds) and man-made (floating breakwaters, fish farms).  Techniques for measuring both the local oceanography and the structural response are listed along with new approaches to measuring important properties.  A number of future applied research topics are identified as being key to advancing the industry, including issues like mooring design, vertical drag coefficients, wave-current interaction, stratification and influence on fauna.
 

Delaux S; Stevens CL; Popinet S (2010) High-resolution computational fluid dynamics modelling of suspended shellfish structures. Environmental Fluid Mechanics  dx.doi.org/10.1007/s10652-010-9183-y