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A study was undertaken on a strip mine in Campbell County, Tennessee to determine what site characteristics permit vegetation establishment and growth on some spoils while preventing it on adjacent ones. Fifty plots were established and spoil samples, 300 each on vegetated and nonvegetated spoils, were taken at depths of 0-5 cm, 10-15 cm, and 25-30 cm to be analyzed for pH, Ca, Mg, K, P, Fe, Al, Mn, Zn, compaction, moisture content, surface temperature, and color. It was found that K, P, Mn, and Zn were in the deficiency range of most plants. The solubility of aluminum and iron increases with low pH, thus increasing the probability of their interactions with and decreased availability of other plant nutrients. Applications of dolomitic limestone to some plots increased pH and may have decreased the availability of some nutrients such as iron.

The growth, nutrient absorption, and internal moisture status of selected woody species in coal mine spoil in response to an induced infection by the ectomycorrhizal fungus Pisolithus tinctorius was studied. Nursery grown loblolly and Virginia pine seedlings infected with Pisolithus and control seedlings were outplanted on a coal mine spoil in Tennessee which had been previously hydroseeded with a mixture of herbaceous ground cover species. Granular fertilizer was applied by broadcasting to one-half of the seedlings of each ectomycorrhizal treatment at the rate of 112 kg/ha NPK. After three years, the survival and growth of loblolly pine infected with Pisolithus was superior to that of the control seedlings, and chemical analyses of foliar samples revealed that the seedlings with Pisolithus ectomycorrhizae had a higher foliar concentration of NO3 and a lower concentration of Zn than the control seedlings. The survival, growth, and nutrient absorption of Virginia pine was not significantly affected by the infection with Pisolithus after two years, but both loblolly and Virginia pine seedlings with Pisolithus ectomycorrhizae exhibited an enhanced ability to absorb water during periods of high moisture stress, as determined by the pressure chamber technique. Fertilization substantially reduced the survival of the seedlings of both species. Sweet birch and European alder were grown under high, intermediate, and low fertility regimes in sand culture containing a mycelial inoculum of Pisolithus tinctorius for five months and then transplanted to coal mine spoil containing an identical Pisolithus inoclum. Control seedlings of each species were similarly grown except that no inoculum was incorporated into the potting media. The nutrient treatments initiated in the sand culture were continued throughout the study. Examinations of the roots of the sweet birch seedlings revealed that high fertility significantly reduced the development of Pisolithus ectomycorrhizae, but Pisolithus formed abundant ectomycorrhizae on the roots of sweet birch grown under the intermediate and low fertility regimes and these seedlings were significantly larger than comparable control seedlings. Chemical analyses of foliar samples revealed that sweet birch seedlings with Pisolithus ectomycorrhizae had a significantly higher foliar concentration of total N and a lower concentration of Mg and Al than the control seedlings. No ectomycorrhizal fungi were found to have infected the roots of the European alder seedlings of any of the ectomycorrhizal-nutrient treatment combinations.

The objective of Evolutionary Computation is to solve practical problems (e.g.optimization, data mining) by simulating the mechanisms of natural evolution. This thesis addresses several topics related to adaptation and self-organization in evolving systems with the overall aims of improving the performance of Evolutionary Algorithms (EA), understanding its relation to natural evolution, and incorporating new mechanisms for mimicking complex biological systems. Part I of this thesis presents a new mechanism for allowing an EA to adapt its behavior in response to changes in the environment. Using the new approach, adaptation of EA behavior (i.e. control of EA design parameters) is driven by an analysis of population dynamics, as opposed to the more traditional use of fitness measurements. Comparisons with a number of adaptive control methods from the literature indicate substantial improvements in algorithm performance for a range of artificial and engineering design problems. Part II of this thesis involves a more thorough analysis of EA behavior based on the methods derived in Part 1. In particular, several properties of EA population dynamics are measured and compared with observations of evolutionary dynamics in nature. The results demonstrate that some large scale spatial and temporal features of EA dynamics are remarkably similar to their natural counterpart. Compatibility of EA with the Theory of Self-Organized Criticality is also discussed. Part III proposes fundamentally new directions in EA research which are inspired by the conclusions drawn in Part II. These changes involve new mechanisms which allow selforganization of the EA to occur in ways which extend beyond its common convergence in parameter space. In particular, network models for EA populations are developed where the network structure is dynamically coupled to EA population dynamics. Results indicate strong improvements in algorithm performance compared to cellular Genetic Algorithms and non-distributed EA designs. Furthermore, topological analysis indicates that the population network can spontaneously evolve to display similar characteristics to the interaction networks of complex biological systems.

Thesis (Ph. D.)--University of Texas at Austin, 2007. / Vita. Includes bibliographical references.

Thesis (Ph.D.)--Hong Kong University of Science and Technology, 2007. / Includes bibliographical references. Also available in electronic version.

Thesis (Ph. D.)--University of Michigan, 1981. / A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy (Botany) at the University of Michigan 1981.

Thesis (M.S.)--Bowling Green State University, 2008. / Document formatted into pages; contains ix, 72 p. : ill. Includes bibliographical references.

Thesis (Ph. D.)--University of Texas at Austin, 2004. / Supervisor: Risto Miikkulainen. Vita. Includes bibliographical references. Also available from UMI.