The goal of this project was to provide information to the County of Hawaii and to the state for the intelligent management of the marine and coastal resources of West Hawaii, particularly the South Kohala and North Kona areas. This was accomplished through compilation of inventories of biological, hydrological, and some oceanographic data for four selected sites, Puako, Waiulua, 'Anaeho'amalu, and Kiholo bays.
Submarine groundwater discharge (SGD) is a spatially pervasive phenomenon that adds freshwater, nutrients, dissolved metals, bacteria, and other constituents to the coastal ocean. This dissertation investigated SGD-related inputs of nutrients and fecal indicator bacteria (Escherichia coli and Enterococcus sp.) to coastal waters in two Hawaiian locations, the north shore of Kaua'i and the Kona coast of Hawai'i. Concentrations of caffeine, which has been used previously as a wastewater tracer, were measured in groundwater and surface water on the north shore of Kaua'i. Both study areas have relatively light levels of urban and agricultural development, and maintaining good water quality is essential for their tourism-based economies, coral reefs, fisheries, and traditional way of life. Radium (Ra), an element with naturally elevated concentrations in coastal groundwater, was used as an SGD tracer and a mass-balance approach was used to quantify SGD. On the north shore of Kaua'i, agriculture was associated with higher nitrate + nitrite concentrations in the fresh SGD component, while phosphate and silica appeared to be controlled by geological differences in aquifer substrate. High ammonium concentrations in the fresh SGD component at one site may have been caused by a leaky cesspool. In Kona, no relation between urban development or agriculture and groundwater nutrient concentrations was observed, but bare lava rock was associated with higher nitrate + nitrite and silica concentrations in fresh SGD. Sites closer to golf courses also had higher nitrate + nitrite concentrations. Conservative estimates of total SGD on the north shore of Kaua'i ranged from 1.3 to 7.8 L per meter per minute, or up to 10% of Hanalei River discharge, and SGD contributed significant nitrate + nitrite inputs to Hanalei Bay. Estimates of SGD in Kona ranged from 5 to 1200 L per meter per minute, with between 10 and 100% of the brackish SGD comprised by the fresh SGD component. SGD-related water and nutrient fluxes on the Kona Coast -- where no rivers and streams are present -- were large compared to those reported for other sites worldwide. Caffeine concentrations in environmental waters on the north shore of Kaua'i ranged from 0-88 ng/L, on the low end of what has been reported for other locations. Metribuzin, an herbicide, was also detected at concentrations from 4-11 ng/L in five groundwater and surface water samples. A sensitivity analysis of Ra-based methods of estimating water ages and coastal mixing rates revealed that water ages shorter than 3 d cannot be estimated with confidence using Ra-based methods, even if the only uncertainty considered is analytical error. In conclusion, this dissertation provides new data about SGD and related inputs of nutrients and bacteria to Hawaiian coastal waters, suggests that even low levels of development may influence nutrient concentrations in coastal groundwater, presents the first caffeine concentrations measured in environmental water samples collected in a tropical setting, and explores the limits of applicability of Ra-based methods of estimating water ages and coastal mixing rates, providing guidance for researchers conducting Ra-based SGD studies in the future.
Why is groundwater the predominant drinking water source in Hawaii? Why are groundwater sources susceptible to pesticide contamination? How long does it take for water in the mountains to journey by land and underground passages to reach the coast? Answers to questions such as these are essential to understanding the principles of hydrology—the science of the movement, distribution, and quality of water—in Hawaii. Due to the humid tropical climate, surrounding ocean, volcanic earth, and high mountains, many hydrologic processes in the Islands are profoundly different from those of large continents and other climatic zones. Management of water, land, and environment must be informed by appropriate analyses, or communities and ecosystems face great uncertainty and may be at risk. The protection of groundwater, coastal waters, and streams from pollution and the management of flood hazards are also significant. This volume presents applications of hydrology to these critical issues. The authors begin by outlining fundamental hydrologic theories and the current general knowledge then expand into a formal discussion specific to Hawaii and the distinctive elements and their interrelations under natural and human-influenced conditions. They include chapters on rainfall and climate, evaporation, groundwater, and surface runoff. Details on the quantification of hydrologic processes are available to those with more technical knowledge, but general readers with an interest in the topic—one of singular importance for the Hawaiian Islands—will find much in the volume that is timely and accessible.
The study of estuaries and coasts has seen enormous growth in recent years, since changes in these areas have a large effect on the food chain, as well as on the physics and chemistry of the ocean. As the coasts and river banks around the world become more densely populated, the pressure on these ecosystems intensifies, putting a new focus on environmental, socio-economic and policy issues. Written by a team of international expert scientists, under the guidance of Chief Editors Eric Wolanski and Donald McClusky, the Treatise on Estuarine and Coastal Science, Ten Volume Set examines topics in depth, and aims to provide a comprehensive scientific resource for all professionals and students in the area of estuarine and coastal science Most up-to-date reference for system-based coastal and estuarine science and management, from the inland watershed to the ocean shelf Chief editors have assembled a world-class team of volume editors and contributing authors Approach focuses on the physical, biological, chemistry, ecosystem, human, ecological and economics processes, to show how to best use multidisciplinary science to ensure earth's sustainability Provides a comprehensive scientific resource for all professionals and students in the area of estuarine and coastal science Features up-to-date chapters covering a full range of topics
This book is a product of the joint JGOFS (Joint Global Ocean Flux Study)/LOICZ (Land–Ocean Interactions in the Coastal Zone) Continental Margins Task Team which was established to facilitate continental margins research in the two projects. It contains signi cant information on the physical, biogeochemical, and ecosystems of continental margins nationally and regionally and provides a very valuable synthesis of this information and the physical, biogeochemical and ecosystem processes which occur on continental margins. The publication of this book is timely as it provides a very strong foundation for the development of the joint IMBER (Integrated Marine Biogeochemistry and Ecosystems Research)/LOICZ Science Plan and Implemen- tion Strategy for biogeochemical and ecosystems research in the continental margins and the impacts of global change on these systems. This initiative will move forward integrated biogeochemical and ecosystems research in the continental margins. We thank all the contributors to this volume and especially Kon-Kee Liu who has dedicated a great deal of time to ensuring a high-quality book is published. IMBER Scienti c Steering Committee Julie Hall LOICZ Scienti c Steering Committee Jozef Pacyna v 1 Preface In general, interfaces between the Earth’s larger material reservoirs (i. e. , the land, atmosphere, ocean, and sediments) are important in the control of the biogeoche- cal dynamics and cycling of the major bio-essential elements, including carbon (C), nitrogen (N), phosphorus (P), sulfur (S), and silicon (Si), found in organic matter and the inorganic skeletons, shells, and tests of benthic and marine organisms.
