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Los estuarios económicamente importantes de Florida podrían verse fuertemente afectados por el aumento del nivel del mar y la alteración del flujo de los ríos, ambos causados por el cambio climático. La resultante mayor salinidad o salinidad del agua podría perjudicar plantas y animales, alterar el hábitat de peces y aves y reducir la capacidad de los estuarios para proporcionar servicios tan importantes como la producción de mariscos y la protección de las costas contra la erosión. Esta publicación contiene información para las partes interesadas, estudiantes, científicos y agencias ambientales interesadas en comprender cómo los cambios en la salinidad impactan los estuarios de Florida con estudios de casos específicos.

Florida’s economically important estuaries could be heavily impacted by sea-level rise and altered river flow, both caused by climate change. The resulting higher salinity, or saltiness of the water, could harm plants and animals, alter fish, and bird habitat, and reduce the capacity of estuaries to provide such important services as seafood production and the protection of shorelines from erosion. This publication contains information for stakeholders, students, scientists, and environmental agencies interested in understanding how changes in salinity impact Florida’s estuaries.

Measurement(s) temperature of water • temperature profile Technology Type(s) digital curation Factor Type(s) lake location • temporal interval Sample Characteristic - Environment lake • reservoir Sample Characteristic - Location global Machine-accessible metadata file describing the reported data: https://doi.org/10.6084/m9.figshare.14619009

Abstract Globally, lake surface water temperatures have warmed rapidly relative to air temperatures, but changes in deepwater temperatures and vertical thermal structure are still largely unknown. We have compiled the most comprehensive data set to date of long-term (1970–2009) summertime vertical temperature profiles in lakes across the world to examine trends and drivers of whole-lake vertical thermal structure. We found significant increases in surface water temperatures across lakes at an average rate of + 0.37 °C decade−1, comparable to changes reported previously for other lakes, and similarly consistent trends of increasing water column stability (+ 0.08 kg m−3 decade−1). In contrast, however, deepwater temperature trends showed little change on average (+ 0.06 °C decade−1), but had high variability across lakes, with trends in individual lakes ranging from − 0.68 °C decade−1 to + 0.65 °C decade−1. The variability in deepwater temperature trends was not explained by trends in either surface water temperatures or thermal stability within lakes, and only 8.4% was explained by lake thermal region or local lake characteristics in a random forest analysis. These findings suggest that external drivers beyond our tested lake characteristics are important in explaining long-term trends in thermal structure, such as local to regional climate patterns or additional external anthropogenic influences.

Históricamente, las agencias ambientales han buscado mejorar la calidad del agua de los lagos y ríos de agua dulce mediante el manejo de un solo nutriente. El fósforo era el nutriente principal de preocupación en los sistemas de agua dulce y el nitrógeno estaba regulado en los sistemas costeros y estuarios. Investigaciones recientes indican que debemos reducir tanto el fósforo como el nitrógeno para revertir los síntomas de eutrofización en todos los sistemas acuáticos. This new 5-page publication of the UF/IFAS Department of Soil and Water Sciences, written by H. Dail Laughinghouse IV, Ashley Smyth, Karl Havens, and Thomas Frazer, is a translation of SGEF190/SG118, "Rethinking the Role of Nitrogen and Phosphorus in the Eutrophication of Aquatic Ecosystems." https://edis.ifas.ufl.edu/sg191

Nitrogen and phosphorus are two nutrients that are essential for the growth and survival of plants and animals but are often present in short supply. Both nitrogen and phosphorus are applied regularly through fertilizer to increase the yield of crops needed to feed human populations and for residential and commercial landscaping purposes. This publication contains information for stakeholders, students, scientists, and environmental agencies interested in understanding how nitrogen and phosphorus affect water resources. Major revision by Ashley Smyth, H. Dail Laughinghouse IV, Karl Havens, and Thomas Frazer; 5 pp. https://edis.ifas.ufl.edu/sg118

Heavy rainfall with Hurricane Irma in 2017 and a rainy spring in 2018 set the stage for large-scale summer algal blooms in Lake Okeechobee and the St. Lucie and Caloosahatchee Rivers and Estuaries. Concerned residents and visitors flocked to social media. Authors Lisa Krimsky, Ed Phlips, and Karl Havens read their posts and tweets and now respond to concerns and questions about algal blooms in this 7-page fact sheet published by UF/IFAS Extension and the Florida Sea Grant College Program. http://edis.ifas.ufl.edu/sg159

This 7-page fact sheet written by Karl E. Havens and published by the Florida Sea Grant College Program, UF/IFAS Extension, provides a history of Lake Okeechobee regulation schedules and an overview of the risks, constraints, and trade-offs that the US Army Corps of Engineers must consider when deciding to release flood water from the lake. http://edis.ifas.ufl.edu/sg154

Microscopic algae in oceans and inland waters sometimes grow to excessive levels called “blooms.” Warmer water temperatures and increased nutrient levels exacerbate blooms, and when nutrients are high, temperature increases of just a few degrees cause exponential increases of algae and blooms. This 4-page fact sheet written by Karl Havens and published by the Florida Sea Grant College Program and UF/IFAS Extension explains why algal blooms can be harmful and provides advice for communities seeking to reduce nutrient levels in their lakes, streams, and other bodies of water. In a warmer future, harmful algal blooms will be much more challenging to control than they are today. http://edis.ifas.ufl.edu/sg153

Future climate change could result in higher temperatures and greater evaporative water loss in Florida. If these changes are not compensated for by more rainfall, the state’s largest water body, Lake Okeechobee, could experience prolonged periods of very low water levels and catastrophic loss of its ecosystem services, which are the benefits that people receive from ecosystems. This 7-page fact sheet provides background, optimal and actual water levels, projected changes in South Florida climate and their effects on water levels in Lake Okeechobee, their effects on ecosystem services, and possible remedies. Written by Karl Havens, and published by the UF Department of Sea Grant, June 2015.

Florida’s economically important estuaries could be heavily impacted by sea-level rise and altered river flow, both caused by climate change. The resulting higher salinity, or saltiness of the water, could harm plants and animals, alter fish and bird habitat, and reduce the capacity of estuaries to provide such important services as seafood production and the protection of shorelines from erosion. This 6-page fact sheet explains the importance of estuaries, salinity in estuaries, and provides examples of stress from extreme high salinity. Then it explores the projected change in climate that could affect salinity in estuaries, how plants and animals would be affected, mitigating effects, and other impacts of climate change on estuaries. Written by Karl Havens, and published by the UF Department of Sea Grant, June 2015. SGEF-218/SG138: Climate Change: Effects on Salinity in Florida's Estuaries and Responses of Oysters, Seagrass, and Other Animal and Plant Life (ufl.edu)

Climate change is expected to result in increased temperatures of nearshore ocean water, and this could lead to increased growth of harmful microorganisms. These include algae that form noxious or toxic blooms, including red tides, and bacteria and other pathogens. This situation could have negative consequences in regard to human health and also Florida’s ocean-related economy. This 6-page fact sheet discusses projected ocean temperatures, how harmful microorganisms living in the ocean might respond, and how this might affect people, and identifies actions that could be taken to reduce these impacts. Written by Karl Havens, and published by Florida Sea Grant, June 2015. SGEF216/SG136: Climate Change and the Occurrence of Harmful Microorganisms in Florida's Ocean and Coastal Waters (ufl.edu)

Florida’s thousands of lakes are shallower than most people realize, and some unique properties of shallow lakes make them challenging to restore if they have been degraded by nutrients or other pollutants. This 4-page fact sheet examines how water managers track nutrients as they cycle through Florida’s lakes. Written by Karl Havens, and published by the UF Department of Sea Grant, January 2013. http://edis.ifas.ufl.edu/sg128

Recent research suggests that climate change will reinforce the negative consequences of man-made eutrophication and make it more difficult to improve water quality in lakes and estuaries. This 3-page fact sheet was written by Karl Havens, and published by the UF Department of Sea Grant, September 2012. SGEF-189/SG127: Effects of Climate Change on the Eutrophication of Lakes and Estuaries (ufl.edu)

For many years, environmental agencies have sought to improve the water quality of lakes and estuaries by reducing inputs of phosphorus. New research indicates that we must reduce both phosphorus and nitrogen to reverse eutrophication symptoms. This 3-page fact sheet was written by Karl Havens and Thomas Frazer, and published by the UF Department of Sea Grant, June 2012. SGEF190/SG118: Rethinking the Role of Nitrogen and Phosphorus in the Eutrophication of Aquatic Ecosystems (ufl.edu)

SL316, a 9-page illustrated guide by Thomas Obreza, Mark Clark, Brian Boman, Tatiana Borisova, Matt Cohen, Michael Dukes, Tom Frazer, Ed Hanlon, Karl Havens, Chris Martinez, Kati Migliaccio, Sanjay Shukla, and Alan Wright, provides a basic, concise, and understandable description of the United States Environmental Protection Agency’s (EPA) proposed numeric nutrient criteria for Florida, the background events that led to its release, some pertinent scientific issues, and implications for the future. Published by the UF Department of Soil and Water Science, February 2010.

Diagnosing causal factors of change at the ecosystem level is challenging because multiple drivers often interact at various spatial and temporal scales. We employ an integrated natural and social science approach to assess potential mechanisms leading to the collapse of an estuarine social-ecological system, and recommend future paths to increased system resilience. Our case study is the collapse of the eastern oyster ( Crassostrea virginica ) fishery in Apalachicola Bay, Florida, USA, and the associated impacts on local resource dependent communities. The oyster fishery collapse is the most recent in a series of environmental stressors to this region, which have included hurricanes and tropical storms, drought, and the Deepwater Horizon oil spill. We found it likely that the oyster collapse was not related to contamination from the recent oil spill, but rather to factors affecting oyster recruitment and survival, which may have been mediated by both human, e.g., fishing-related habitat alteration, and environmental, e.g., increased natural mortality from predators and disease, factors. The relative impact of each of these factors is likely to increase in the future because of changing climate and increased demand for fishery, water, and petroleum resources. Successful restoration and persistence of a viable oyster fishery will depend on: (1) implementation of some minimal best management practices, e.g., extensive habitat restoration via shell addition, and some spatial closures to harvest, (2) improving environmental knowledge and promoting episodic learning through enhanced monitoring and experimental management, and (3) continued community engagement necessary to produce adaptable governance suitable to responding to future unexpected challenges.

Resource management decisions often are based on a combination of scientific and political factors. The interaction of science and politics is not always apparent, which makes the decision-making process appear arbitrary at times. In this paper, we present a case study involving Lake Okeechobee, a key environmental resource in South Florida, USA, to illustrate the role that science played in a high-profile, highly contentious natural resource management decision. At issue was whether or not to lower the water level of Lake Okeechobee. Although scientists believed that a managed recession (drawdown) of water level would benefit the lake ecosystem, risks were present because of possible future water shortages and potential environmental impacts to downstream ecosystems receiving large volumes of nutrient-rich fresh water. Stakeholders were polarized: the agriculture and utility industries favored higher water levels in the lake; recreation users and businesses in the estuaries wanted no or minimal discharge from the lake, regardless of water level; and recreation users and businesses around the lake wanted lower water levels to improve the fishery. Jurisdictional authority in the region allowed the Governing Board of the South Florida Water Management District to take emergency action, if so warranted. Based on information presented by staff scientists, an aggressive plan to release water was approved in April 2000 and releases began immediately. From a hydrological perspective, the managed recession was a success. Lake levels were lowered within the targeted time frame. In addition, water quality conditions improved throughout the lake following the releases, and submerged plants displayed a dramatic recovery. The short-term nature of the releases had no lasting negative impacts on downstream ecosystems. Severe drought conditions developed in the region during and following the recession, however. Severe water use restrictions were implemented for several months. There also were impacts to the local economy around the lake, which depends heavily on recreational fishing; use of boat launch areas was curtailed because of the low water levels in the lake. This case study provides an example of how science was used to justify a controversial decision. Although the environmental basis for the decision was validated, unexpected or unpredictable climatic results led to socioeconomic challenges that offset the environmental successes.

This study examined the relative contributions of bacterial and phytoplankton production to the pelagic carbon flow of Lake Okeechobee, a large and shallow subtropical lake. Due to the predominance of cyanobacteria in this lake, we hypothesized that bacterial carbon flow would be larger than phytoplankton carbon flow to grazers. Using epifluorescent and light microscopy and radiotracer techniques, we measured the carbon biomass of planktonic functional groups and carbon flow between these groups. The functional groups that we used in this study included: picophytoplankton, autotrophic nanoflagellates (ANAN), microphytoplankton, bacteria, heterotrophic nanoflagellates (HNAN), ciliates, microzooplankton (rotifers and copepod nauplii) and macrozooplankton (cladocerans, copepodites and adult copepods). Microphytoplankton dominated the carbon biomass of all plankton, whereas the calanoid copepod, Diaptomus, dominated the carbon biomass of the grazers. Phytoplankton carbon flow often was higher than bacterial carbon flow to grazers; however, bacterial carbon constituted a large percentage of the total carbon flow to grazers (33.7 22.4%). Bacterial carbon provided roughly one quarter of the carbon flow to macrozooplankton (27.1 25.4%), whereas it provided half of the carbon flow to microzooplankton (57.4 20.3%) and to protozoans (47.2 25.8%). These results suggest that microbial pathways play an important role in the energetics of subtropical lake plankton communities. Although microbial loop pathways are important in many systems, direct bacterial carbon flow to macrozooplankton also may be important in copepod- and cyanobacteria-dominated lakes. [ABSTRACT FROM AUTHOR]