Coastal zone management--Florida

The coastal system provides habitat, storm protection, and economic value. In particular, Florida’s beaches are subject to chronic coastal erosion resulting from natural and anthropogenic influences. The most common mitigation response is the nature-based solution of beach nourishment. While this method is widely considered effective, quantifying changes from the dredge and placement on the physical environment is critical to ensure best management practices. The first step in addressing the need to identify gaps in knowledge relating to natural and human-induced changes to the continental shelf, a comprehensive literature review of the US East and Gulf coast continental shelves was conducted identifying needs for more expansive sand searches, a greater understanding of storm impacts on shelf morphodynamics, planning for long-term use of offshore sediment sources, and the impact of dredging on habitats. This study then evaluated the northern Palm Beach County beaches adjacent to the Jupiter Inlet over multiple years to understand the effects of natural and human influence on the morphology and sedimentology of the beach-nearshore environment. Beach sediment was coarser near the Inlet and finer downdrift (south). Seasonal changes in the nearshore from storms decreased the grain size and eroded beaches, whereas nourishment increased grain size and expanded beach width. Influences of physical characteristics of the beach-nearshore environment on the ecosystem were examined based on two important marine species: loggerhead sea turtles and blacktip sharks. No adverse impacts from restoration activities were found on loggerhead reproductive success. However, the active 2020 hurricane season resulted in lower reproductive success metrics. The blacktip shark migration coincides with the typical nourishment construction window. High turbidity in the nearshore was documented in association with multiple nourishment events during the two-year study. The blacktip sharks were quantified in the nearshore south of the nourishment; however, whether the turbidity was influencing the shark aggregates or habitat preference remains unknown. These results support numerous benefits of beach nourishment but suggest further research is needed to evaluate how project construction may impact nearshore fauna. The findings of this study are important for coastal managers who may consider reviewing best management practices of the beach-nearshore system.

Coastal landscape plays a vital role in reflecting various natural processes. Vegetation resource management improves the quality of life above the surface of the earth. Due to factors such as climatic change, urban development, and global warming, monitoring the coastal region as well as its vegetation has indeed become a challenge to mankind. The purpose of the study is to propose an effective low-cost methodology to monitor the 120- acre Jupiter Inlet Lighthouse Outstanding Natural Area (ONA) located in Jupiter, Florida (USA) using Unmanned Aerial Systems (UAS) Imagery deployed with RedEdge Micasense Multispectral sensor having five bands. Since, UAS provides high resolution imagery at lower altitudes, it has a lot of potential for variety of applications. This research aims to (1) Automate the extraction of shoreline and coastline through Modified Normalized Difference Index (MNDI), thereby comparing it with the manually digitized shoreline using transect-based analysis (2) Automate the volume change computation, as the area has been affected due to various natural and anthropogenic factors in the past few decades. (3) Perform shoreline change detection for the time period 1953 to 2021 (4) Develop an algorithm to differentiate ground and non-ground points along the shore region and generate Digital Terrain Model (DTM) (5) Land use and Land cover (LULC) mapping using different band combinations and compare its result using deep learning approach.

Multiple tracers, such as DO, ammonia, TN, TOC, E. coli, TC, and Enterococcus were
analyzed in order to identify and characterize trends in coastal water quality. This study
focused on three factors; wastewater disposal and treatment alternative; season; and
human population density. Samples were collected in representative sites of urban
Broward County and of rural Taylor County, FL, for pair-wise comparison. Sites
included areas connected to the public sewer network and served by on-site treatment and
disposal system (OSTDS). Sampling activities were conducted through seasonal low and
seasonal high water table elevation (SLWT and SHWT), and always on slack to outgoing
tide. Different statistical tests were performed, including: t-Tests, correlation analysis,
principal component analysis (PCA), and analysis of variance (ANOVA). Results
suggested that water quality is lower: in urban sites compared to rural sites; in OSTDS
sites compared to sewered areas; and SHWT compared to SLWT.

Few phosphorus (P) depleted coastal marine ecosystems have been examined for their capacity to hydrolyze phosphomonoesters (PMEs). The purpose of this study was to examine seasonal APA partitioning between water column fractions (phytoplankton, bacteria and freely dissolved) and benthic autotrophs in Florida Bay, a P limited shallow estuary using low fluorescent substrate (MUF-P) concentrations (≤2.0 μm). APA was higher at the western and northcentral (751 and 695 nmol L^-1 h^-1) sites and driven by cyanobacterial blooms, compared to the P limited northeastern (359 nmol L^-1 h^-1) site The free dissolved fraction (<0.2 μm) accounted for the most APA (~50%), followed by the phytoplankton (>1 μm; 30%) and bacteria fraction (<0.2-> 1.2 μm; 8%). Thaiassia testudinum leaves with their associated epiphytes contributed modestly to water column APA (14 and 20%), and only during non-bloom conditions. Rapid hydrolysis of PMEs (undetected in most samplings) in Florida Bay is probably driven by high concentration of organic substrates for microbial and cyanobacterial activity which results from the close association of the shallow water column with the underlying seagrass community and adjacent Everglades wetlands.

Evaluations of shore erosion and protection in Florida are constrained by time and space. This study characterizes about 95% of Florida's beaches based on the degree of urban development, direction and rates of shoreline change, presence of sensitive ecological communities, and distribution of sea defense works. The 22 coastal-county maps prepared for this study show that approximately 195 km (16%) of Florida's beaches are eroding and 283 km (23%) are protected by engineering works. About 72% of eroded beaches are geographically associated with inlets. Sand management at inlets is crucial to improve erosion mitigation in Florida. Suggestions designed to enhance mitigation of beach erosion are based on comparative analyses of potential environmental impacts, costs, and limitations of shore protection works. Alternative technologies that use combined techniques (i.e. bed fluidization/jet-pumps, beach nourishment/dewatering systems, or detached breakwaters) are more efficient, less expensive, and less environmentally hazardous than conventional methods.