Download or read book Spatial Dynamics in the Growth and Spread of Halimeda and Dictyota in Florida Reefs a Simulation Modeling Approach written by Aletta Tiangco Yįguez and published by . This book was released on 2007 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Macroalgae are an important part of the coral reef ecosystem that has largely been overlooked. However, in the past few decades their abundances have increased and this has been attributed to combinations of coral mortality opening up space in the reef, decreased grazing and increased nutrient load in reefs. This dissertation illustrates a novel means of investigating the effect of various growth and disturbance factors on the dynamics of macroalgae at three different levels (individual, population and 3-species community). Macroalgae are modular and clonal organisms that have differing morphologies depending on the environment to which they are exposed. These traits were exploited in order to understand the factors that were acting on the dominant and common macroalgae in the Florida Reef Tract: Halimeda tuna, Halimeda opuntia and Dictyota sp. The agent-based model SPREAD (SPatially-explicit REef Algae Dynamics) was developed to incorporate the key morphogenetic characteristics of clonality and morphological plasticity. It revolves around the iteration of macroalgal module production in response to light, temperature, nutrients, and space availability, while fragmentation is the source for mortality or new individuals. These processes build the individual algae then the population. The model was parameterized through laboratory experiments, existing literature and databases and results were compared to independently collected field data from four study sites in the Florida Keys. SPREAD was run using a large range of light, temperature, nutrient and disturbance (fragmentation without survival) levels and yielded six morphological types for Halimeda tuna, and two each for Halimeda opuntia and Dictyota sp. The model morphological types that matched those measured in two inshore patch reefs (Cheeca Patch and Coral Gardens) and two offshore spur and groove reefs (Little Grecian and French Reef), were formed in conditions that were similar to the environmental (light, nutrient and disturbance) conditions in the field sites. There were also differences between species in the important factors that influenced their morphologies, wherein H. opuntia and Dictyota were more affected by disturbance than growth factors, while H. tuna morphology was affected by both. Allowing for fragmentation with survival in the model resulted in significantly higher population abundances (percent cover and density). The highest abundances were achieved under high fragment survival probabilities and a high disturbance level (but not large fragment sizes). Incorporating fragmentation with survival and simulating the variations in light, nutrients and disturbance between the inshore patch reefs and offshore spur and groove reefs in SPREAD led to comparable abundances of Halimeda in the virtual reef sites. Adding competition for space and light and epiphytism by Dictyota on the two Halimeda species suggests that it can regulate the populations of the three macroalgae. However, comparing model abundances to the field, competition may not be a strong regulating force for H. tuna in all the sites and H. opuntia in the patch reefs. H. opuntia in the offshore reefs is possibly competitively regulated. Although SPREAD was not able to capture the patterns in the population abundance of Dictyota, this points to the potential importance of other morphometrics not captured by the model, a variation in growth curves between reef habitats, or the differential contribution of sexual reproduction.
Download or read book An Integrated Empirical and Modeling Approach to Evaluate Determinants of Community Structure and Alternate Stable States Dynamics on Tropical Reefs written by Ranjan Muthukrishnan and published by . This book was released on 2013 with total page 115 pages. Available in PDF, EPUB and Kindle. Book excerpt: Coral reefs have seen precipitous declines across the globe that are generally associated with transitions to reefs dominated by algae. Understanding the causes and dynamics of these transitions is of critical importance for the implementation of effective management strategies to protect reefs that remain healthy and to recover degraded reefs. To address these issues I evaluated the potential resilience of coral reefs at Isla Contadora, Panamá in the Easter Tropical Pacific (ETP), to different anthropogenic stresses with an integrated approach using empirical and modeling methods. Direct community response to stressors was investigated with experimental manipulations of herbivore abundance, nutrient supply and sediment loading. These experiments showed that any of the three stressors could push reefs toward algal dominance but that the effects of particular stressors were variable and highly dependent on the environmental context in which they were applied. In addition, I identified that herbivory rates and nutrient availability, two critical controls of community structure, vary in response to the local abundance of coral and algae. Because both processes are stronger in the community state they support they act as positive feedbacks pushing reefs toward divergent community states and producing patchy spatial patterning. Using these empirical results I developed a spatially explicit simulation model that incorporated and tested if the environmental conditions measured in the ETP supported alternative stable states (ASS). ASS theory is a dominant conceptual framework for understanding processes that support resilience of ecological communities in the face of anthropogenic disturbance, and, by combining empirical and modeling methods, I propose a rapid and non-destructive method to evaluate ASS in fragile habitats. Using the model I demonstrated that the presence of positive feedback are essential for ASS and the strength of those feedbacks is the critical factor that separates systems with phase shifts and ASS. With data from Isla Contadora I was also able to identify the particular conditions under which ETP reefs should display ASS and demonstrated that the reefs at Isla Contadora exist within that range suggesting they exist as ASS.
Download or read book Report on the Florida Reefs written by Louis Agassiz and published by . This book was released on 1882 with total page 586 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Islands in the Sand written by Daniel A. McCarthy and published by Springer Nature. This book was released on 2020-10-22 with total page 480 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nearshore hardbottom reefs of Florida’s east coast are used by over 1100 species of fishes, invertebrates, algae, and sea turtles. These rocky reefs support reproduction, settlement, and habitat use, and are energy sources and sinks. They are also buried by beach renourishment projects in which artificial reefs are used for mitigation. This comprehensive book is for research scientists and agency personnel, yet accessible to interested laypersons including beachfront residents and water-users. An unprecedented collection of research information and often stunning color photographs are assembled including over 1250 technical citations and 127 figures. These shallow reefs are part of a mosaic of coastal shelf habitats including estuarine seagrasses and mangroves, and offshore coral reefs. These hardbottom habitats are federally designated as Essential Fish Habitats - Habitats of Particular Concern and are important feeding areas for federally-protected sea turtles. Organismal and assemblage responses to natural and man-made disturbances, including climate change, are examined in the context of new research and management opportunities for east Florida’s islands in the sand.
Download or read book Towards an Ecosystem Approach for Non target Reef Fishes Habitat Uses and Population Dynamics of South Florida Parrotfishes perciformes Scaridae written by Helena Molina-Ureą and published by . This book was released on 2006 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The goal of this research was to develop statistically robust ecosystem-based approaches, while optimizing data acquisition on relatively unexploited fish species in South Florida reefs, i.e., parrotfishes, Family Scaridae, in Biscayne Bay (with seasonal roller frame beam trawl surveys, 1996-2000) and Florida Keys (with annual Reef Fish Visual Censuses, 1997-2001), by following these steps: (I) analysis of information gaps for the stocks, including systematics, biogeography, population dynamics, reproductive ecology, trophodynamics, habitat use, and fisheries dynamics of Western Atlantic parrotfishes; (II) determination of primary research objectives from prioritization in Step I; (III) determination of essential fish habitats, ontogenetic shifts, migrations, and reef-seagrass habitat, from integration of stratified sampling design for fisheries-independent surveys, habitat selection theory-based analyses, and length-based analyses; (IV) estimation of population dynamics and fisheries-specific parameters encompassing life history demographics from empirical data or comparisons to theoretical expectations adapted to local conditions; (V) simulation modeling of a realistic range of fishing scenarios and demographic characteristics to evaluate the efficacy of potential traditional fisheries and spatial management strategies; and (VI) application of sampling optimization procedures and fisheries ecology approaches. Four scarid species had an estimated combined abundance of ca. 36.8 x 106 individuals in the Florida Keys. Connectivity among seagrass beds, coral reefs and deep waters had three major patterns: seagrass dwellers, reef dwellers, with inshore-to-offshore ontogenetic, and a seagrass-reef connection, using Biscayne Bay as an important recruitment ground. Marine protected areas of the Florida Keys National Marine Sanctuary did not show effects on abundance, size composition or spatial distribution of any parrotfish studied. Simulations suggested relatively short longevities (5-10 years), moderate body growth curvature, high instantaneous natural mortality rates (0.3-0.6 y super minus one), and low annual survival rates (27-54%). Simulated estimates of fishing mortalities ranged from 0.3 to 0.6 y super minus one, indicating low levels of exploitation, but low Spawning Potential Ratios (SPR = 23.5-26%). Proposed potential exploitation based on a legal minimum size equal to their size at first maturity and fishing rates equal or below to their natural mortality should secure SPR values at 45-48%.
Download or read book Publications of the Florida Marine Research Institute written by Florida Marine Research Institute and published by . This book was released on 1995 with total page 138 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Oceanic Abstracts with Indexes written by and published by . This book was released on 1980 with total page 660 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Publications of the Florida Marine Research Institute written by Florida Marine Research Institute and published by . This book was released on 1993 with total page 118 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book South Florida Carbonate Sediments written by Robert N. Ginsburg and published by . This book was released on 1972 with total page 90 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Spatial Modeling Approach to Pelagic Ecosystems written by Ivan Tristan Show and published by . This book was released on 1977 with total page 270 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Development of Movement Models to Assess the Spatial Dynamics of Marine Fish Populations written by Robert Humston and published by . This book was released on 2001 with total page 510 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book On the Origin Growth Substructure and Chronology of the Florida Reef written by Edward Bissell Hunt and published by . This book was released on 1863 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Parametric Non parametric and Statistical Modeling of Stony Coral Reef Data written by Armando Hoare and published by . This book was released on 2008 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: ABSTRACT: Like coral reefs worldwide, the Florida Reef Tract has dramatically declined within the past two decades. Monitoring of 40 sites throughout the Florida Keys National Marine Sanctuary has undertaken a multiple-parameter approach to assess spatial and temporal changes in the status of the ecosystem. The objectives of the present study consist of the following: In chapter one, we review past coral reef studies; emphasis is placed on recent studies on the stony corals of reefs in the lower Florida Keys. We also review the economic impact of coral reefs on the state of Florida. In chapter two, we identify the underlying probability distribution function of the stony coral cover proportions and we obtain better estimates of the statistical properties of stony coral cover proportions. Furthermore, we improve present procedures in constructing confidence intervals of the true median and mean for the underlying probability distribution. In chapter three, we investigate the applicability of the normal probability distribution assumption made on the pseudovalues obtained from the jackknife procedure for the Shannon-Wiener diversity index used in previous studies. We investigate a new and more effective approach to estimating the Shannon-Wiener and Simpson's diversity index. In chapter four, we develop the best possible estimate of the probability distribution function of the jackknifing pseudovalues, obtained from the jackknife procedure for the Shannon-Wiener diversity index used in previous studies, using the xi nonparametric kernel density estimate method. This nonparametric procedure gives very effective estimates of the statistical measures for the jackknifing pseudovalues. Lastly, the present study develops a predictive statistical model for stony coral cover. In addition to identifying the attributable variables that influence the stony coral cover data of the lower Florida Keys, we investigate the possible interactions present. The final form of the developed statistical model gives good estimates of the stony coral cover given some information of the attributable variables. Our nonparametric and parametric approach to analyzing coral reef data provides a sound basis for developing efficient ecosystem models that estimate future trends in coral reef diversity. This will give the scientists and managers another tool to help monitor and maintain a healthy ecosystem.
Download or read book Why Does the World Stay Green written by TCR White and published by CSIRO PUBLISHING. This book was released on 2005-10-03 with total page 129 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nearly every form of life has the capacity to multiply and increase at a really astonishing rate. Think of plagues of locusts or mice. Clearly, for the vast majority of animals this does not happen, otherwise they would swamp the world and destroy all the plants. So why doesn’t it happen, and why does the world stay green? The concept explored in this book contends that animals are not controlled through predation but because plants have outwitted them, they cannot obtain enough of the food they must have to reproduce and grow. Why Does the World Stay Green? explains, in simple terms, how this comes about in nature and describes some of the many fascinating ways in which animals have evolved to cope with this usually chronic shortage of an essential resource. It is fascinating and easy-reading for anyone interested in natural history. The author, TCR White, has acted as a strong influence for the last 40 years on the ecological community, presenting confronting and at times controversial theories on the limiting role that nitrogen plays in the evolution of life. Why Does the World Stay Green? reveals this fascinating and important ecological theory.
Download or read book Coral Reefs of the Eastern Tropical Pacific written by Peter W. Glynn and published by Springer. This book was released on 2016-08-12 with total page 666 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book documents and examines the state of health of coral reefs in the eastern tropical Pacific region. It touches on the occurrence of coral reefs in the waters of surrounding countries, and it explores their biogeography, biodiversity and condition relative to the El Niño southern oscillation and human impacts. Additionally contained within is a field that presents information on many of the species presented in the preceding chapters.
Download or read book Algal Chemical Ecology written by Charles D. Amsler and published by Springer Science & Business Media. This book was released on 2007-11-03 with total page 322 pages. Available in PDF, EPUB and Kindle. Book excerpt: Yet another Springer world-beater, this is the first ever book devoted to the chemical ecology of algae. It covers both marine and freshwater habitats and all types of algae, from seaweeds to phytoplankton. While the book emphasizes the ecological rather than chemical aspects of the field, it does include a unique introductory chapter that serves as a primer on algal natural products chemistry.
Download or read book Coral Reefs An Ecosystem in Transition written by Zvy Dubinsky and published by Springer Science & Business Media. This book was released on 2010-12-02 with total page 541 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book covers in one volume materials scattered in hundreds of research articles, in most cases focusing on specialized aspects of coral biology. In addition to the latest developments in coral evolution and physiology, it presents chapters devoted to novel frontiers in coral reef research. These include the molecular biology of corals and their symbiotic algae, remote sensing of reef systems, ecology of coral disease spread, effects of various scenarios of global climate change, ocean acidification effects of increasing CO2 levels on coral calcification, and damaged coral reef remediation. Beyond extensive coverage of the above aspects, key issues regarding the coral organism and the reef ecosystem such as calcification, reproduction, modeling, algae, reef invertebrates, competition and fish are re-evaluated in the light of new research and emerging insights. In all chapters novel theories as well as challenges to established paradigms are introduced, evaluated and discussed. This volume is indispensible for all those involved in coral reef management and conservation.
