Ecosystems involve highly non-linear interactions between species and their environments over wide ranges of scales. These interactions give rise to population number densities that are highly intermittent in both space and time. The simplest hypothesis about the variability of individual density fields is that they are scale invariant in space-time. For some cases, such as plankton, this has been demonstrated empirically. In addition, at a fixed space-time location there is a well-established information theory approach for treating the density statistics for different species. In this "species space", there are already two scaling biodiversity models: the (mono) fractal model and the lognormal model. / The simplest treatment combining real and species space scaling is obtained by considering an anisotropic multifractal cascade in a (5-D) species-space-time space. With the help of a unique data base involving nearly three hundred different species densities, each over a spatial range of approximately 40, 0.5m x 0.5m samples from six underwater sites in the Saint Lawrence Estuary, this simple "superscaling" model is tested. It is shown that the scaling of all species densities is compatible with a "bilinear" multifractal model, where an "elliptical dimension" parameter characterises the anisotropy of species-real space. This information is then used to numerically simulate the spatial variability of joint species densities, and it is discussed how this framework can be used to define scale invariant measures of biodiversity.

Thesis (Ph.D.)--The University of Toledo, 2006. / (UnM)AAI3218587. Adviser: Daryl L. Moorhead. Source: Dissertation Abstracts International, Volume: 67-05, Section: B, page: 2328.

Thesis (Ph.D.)--Lehigh University, 2007. / Adviser: Frank Pazzaglia.

Thesis (Ph.D.)--The University of Alabama at Birmingham, 2006. / (UMI)AAI3227075. Adviser: James B. McClintock. Source: Dissertation Abstracts International, Volume: 67-07, Section: B, page: 3554.

Thesis (Ph.D.)--Boston University, 2007. / (UMI)AAI3259864. Source: Dissertation Abstracts International, Volume: 68-04, Section: B, page: 2036. Adviser: Jelle Atema.

Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 2007. / Source: Dissertation Abstracts International, Volume: 68-07, Section: B, page: 4231. Adviser: James W. Dalling. Includes bibliographical references (leaves 103-116) Available on microfilm from Pro Quest Information and Learning.

Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 2008. / Source: Dissertation Abstracts International, Volume: 69-05, Section: B, page: 2881. Adviser: Anton G. Endress. Includes bibliographical references. Available on microfilm from Pro Quest Information and Learning.

Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 2008. / Source: Dissertation Abstracts International, Volume: 69-05, Section: B, page: 2736. Adviser: Andrew Suarez. Includes bibliographical references (leaves 83-99) Available on microfilm from Pro Quest Information and Learning.

Thèse (M.Sc.)--Université de Sherbrooke (Canada), 2008. / Titre de l'écran-titre (visionné le 1 février 2007). In ProQuest dissertations and theses. Publié aussi en version papier.

Thesis (Ph.D.)--Lehigh University, 2008. / Adviser: Murray Itzkowitz.