Effects of landscape gradients on wetland vegetation communities: information for large-scale restoration

Projects of the scope of the restoration of the Florida Everglades require substantial information regarding ecological mechanisms, and these are often poorly understood. We provide critical base knowledge for Everglades restoration by characterizing the existing vegetation communities of an Everglades remnant, describing how present and historic hydrology affect wetland vegetation community composition, and documenting change from communities described in previous studies. Vegetation biomass samples were collected along transects across Water Conservation Area 3A South (3AS)

Research objectives to support the South Florida Ecosystem Restoration initiative-Water Conservation Areas, Lake Okeechobee, and the East/West waterways

The South Florida Ecosystem encompasses an area of approximately 28,000 km2 comprising at least 11 major physiographic provinces, including the Kissimmee River Valley, Lake Okeechobee, the Immokalee Rise, the Big Cypress, the Everglades, Florida Bay, the Atlantic Coastal Ridge, Biscayne Bay, the Florida Keys, the Florida Reef Tract, and nearshore coastal waters. South Florida is a heterogeneous system of wetlands, uplands, coastal areas, and marine areas, dominated by the watersheds of the Kissimmee River, Lake Okeechobee, and the Everglades. Prior to drainage, wetlands dominated the ecosystem, covering most of central and southern Florida. The landscapes included swamp forests; sawgrass plains; mosaics of sawgrass, tree islands, and ponds; marl-forming prairies dominated by periphyton; wet prairies dominated by Eleocharis and Nymphaea; freshwater marshes; saltwater marshes; cypress strands; and a vast lake-river system draining into Lake Okeechobee. Elevated areas that did not flood supported pine flatwoods, pine rocklands, scrub, tropical hardwood hammocks, and xeric hammocks dominated by oaks. The natural seascapes of South Florida consisted of riverine and fringe mangrove forests; beaches and dunes; seagrass beds; intertidal flats; mud banks; hardbottom communities; coral reefs; and open, inshore shallows. All these habitats were interconnected on an extremely low topographic gradient (2.8 cm/km) with elevations ranging from about 6 m at Lake Okeechobee to below sea level at Florida Bay. The Science SUb-Group (1993) described the defining characteristics of the South Florida Ecosystem and the problems that resulted from hydrologic alterations and other anthropogenic changes. Restoration objectives were proposed for each sub-regionand the region as a whole. The overall goal of the restoration effort is to restore a sustainable South Florida Ecosystem that preserves the valued properties of South Florida's natural systems and supports productive agriculture-, fishery-, and tourist. based economies and a high quality of urban life. Sustainability means high natural productivity, human and ecosystem health, and resiliency to climatic extremes and catastrophic events. It also means accommodation of needs of human systems-flood control, irrigation, and drinking water supply. SCOPE This section addresses the entire ecosystem, cutting across the artificial boundaries of designated subregions, as well as geopolitical and geomorphological boundaries, to present the broader issues of deVeloping an interagency and interdisciplinary ecosystem-based science program to support South Florida restoration. Here we discuss the general premise and the general approach, with brief discussions on monitoring, modeling, and special studies. The latter two topics are covered in greater detail in other sections. (PDF contains 119 pages

Convex Dynamics and Applications

This paper proves a theorem about bounding orbits of a time dependent dynamical system. The maps that are involved are examples in convex dynamics, by which we mean the dynamics of piecewise isometries where the pieces are convex. The theorem came to the attention of the authors in connection with the problem of digital halftoning. \textit{Digital halftoning} is a family of printing technologies for getting full color images from only a few different colors deposited at dots all of the same size. The simplest version consist in obtaining grey scale images from only black and white dots. A corollary of the theorem is that for \textit{error diffusion}, one of the methods of digital halftoning, averages of colors of the printed dots converge to averages of the colors taken from the same dots of the actual images. Digital printing is a special case of a much wider class of scheduling problems to which the theorem applies. Convex dynamics has roots in classical areas of mathematics such as symbolic dynamics, Diophantine approximation, and the theory of uniform distributions.Comment: LaTex with 9 PostScript figure

Spatial and Temporal Changes in Tree Islands of the Arthur R. Marshall Loxahatchee National Wildlife Refuge in Response to Altered Hydrologies

Loxahatchee can be grouped into three zones according to the patterns of change of tree islands observed from 1950 to 1991. 1 ) the edge of the refuge adjacent to the canals, 2) the eastern interior of the refuge, and 3) the western interior of the refuge. The general trend is for tree islands Along the edge of the refuge to have decreased in size, number, and percent cover, while those on the interior increased in size, nunber, and percent cover. Results from this study illustrate the importance of flow magnitude as well as hydroperiod and depth in stucturing patterns of tree islands within this peat wetland. Restoration of historic hydroperiods and depths without historic flow patterns may not be sufficient to restore or maintain the historic pattern and function of the system. (60 pages

Phase behavior and application studies of cellulose nano-crystals synthesized by acetic acid

Cellulose is the most abundant source of biomass in the world. Nano-cellulose possesses the extraordinary mechanical properties of high Young\u27s modulus and great tensile strength found in natural cellulose fiber. However, during drying, abundant hydrogen bonding can agglomerate the nano-cellulose, hindering its mechanical properties. Thus it is important to ensure that the nano-cellulose is utterly deagglomerated in order to improve its applicability. We used various sonication and centrifugation techniques to successfully deagglomerate the cellulose. To better understand the phase behavior of the cellulose nanocrystals, various concentrations of CNC-AA were left to sit in glass vials, while the phase behavior was optically observed over time. After several weeks, there was no discernable phase separation, yet liquid crystalline behavior was noticed in certain concentrations utilizing polarized light microscopy. In order to then use the stable CNC-AA suspensions as films (for eventual application in MEMS devices) a spin-coating procedure onto silicon wafers was optimized. Using AFM and interferometry, the structure and thickness of the CNC-AA films were observed

Remember, Reclaim, Restore: A Post-Pandemic Pedagogy of Indigenous Love in Early Childhood Education

This article discusses Early Childhood education, it’s settler colonial roots, the harm it has caused for Indigenous children and people and the possibilities for a better Indigenous Early Childhood education pre and post COVID-19. Reclaiming the education of our Indigenous children in Early childhood through the centering of Indigenous languages, cultures, knowledge systems, etc. is paramount to a loving and just pathway forward for Indigenous children. For all of us

The Cape San Blas Ecological Study

Eglin AFB on Cape San Blas consists of approximately 250 acres located about 180 miles east of the main Eglin reservation. This area lies on the S1. Joseph peninsula, part of a dynamic barrier island chain that extends across the northern Gulf of Mexico. Due to the natural forces that formed Cape San Blas and those that maintain this area, St. Joseph Peninsula has experienced severe land form change over time (see GIS land form change maps). These changes allow for fluctuations in habitat types along Cape San Blas (see GIS land cover change maps)that influence the floral and faunal species using this area. The dynamic environment along Cape San Blasincludes flatwoods, interdunal swale, rosemary scrub, and beachfront. These habitats support a wide array of species, including several threatened and endangered species such as the loggerhead sea turtle (Caretta caretta), PipingPlover (Charadnus melodus), Least Tern (Sterna antillarum), and Bald Eagle (Haliaeetus leucocephalus). Proper management of these species and their habitats require knowledge of their abundance and distribution, and the effects disturbances have on their survival. In addition to threatened and endangered flora and fauna, Cape San Blas also supports tourists and recreationists. Although Gulf County is sparsely populated, with approximately 13,000 inhabitants throughout 578 square miles, summer tourism and heavy recreational use of beaches for fishing, crabbing, and shelling place continued and increasing pressure on the natural resources of these areas (Rupert 1991). Gulf County is also one of the few remaining counties in Florida that permits vehicular traffic on its beaches, including Cape San Blas. In addition to recreational use of these habitats;EAFB also uses the area for military missions. Air Force property on Cape San Blas is primarily used for radar tracking of flying missions over the Gulf of Mexico, although in recent years it has been used for missile launchings and other various military activities. To allow continued military and public use of Air Force property while also protecting the unique flora and fauna of the area,EAFB proposed a characterization of the resources found along Cape San Blas. A complete inventory of the physical features of the area included investigating topography, soil chemistry, hydrology, archeology, and the dynamics of land mass and land cover change over time. Various thematic layers within a geographic information system (GIS) were used to spatially portray georeferenced data. Large scale changes over time were assessed using stereo aerial photography. Vegetation transects, soil samples, elevation transects, an archeological survey, freshwater wells, and a tidal monitor were used to investigate the remaining features. (247 page document

The Cooler Koozie, optimizing thermal insulation for beverage consumption

Our work aims to develop a new koozie with insulating properties that improve upon the current available commercial options. The hot climate of South Carolina, especially during football season, can heat a consumer\u27s beverage to an unenjoyable temperature in a very short period of time. To recreate these hot conditions in a lab setting, our team designed a hot air circulation box with a temperature controller. Our baseline for improvement was established by testing plain cola cans without koozies, cans with basic foam koozies, and cans with more expensive, name brand koozies. Based on these results, we set out to design a new koozie that would outperform those on the current market. Our design focuses on separating the can from the environment by maximizing captured air space between the two. Air is exploited in our design due to its low thermal conductivity, or ability to reduce heat transfer. The material of construction for our koozie is thin wall, flexible PVC tubing wound around in a spiral manner, and then glued together. We are also investigating different diameter tubing to determine the effect differing amounts air space. These results show that our new design has improved insulating properties compared to commercially available koozies while also being aesthetically pleasing

Reconstruction of eye movements during blinks

In eye movement research in reading, the amount of data plays a crucial role for the validation of results. A methodological problem for the analysis of the eye movement in reading are blinks, when readers close their eyes. Blinking rate increases with increasing reading time, resulting in high data losses, especially for older adults or reading impaired subjects. We present a method, based on the symbolic sequence dynamics of the eye movements, that reconstructs the horizontal position of the eyes while the reader blinks. The method makes use of an observed fact that the movements of the eyes before closing or after opening contain information about the eyes movements during blinks. Test results indicate that our reconstruction method is superior to methods that use simpler interpolation approaches. In addition, analyses of the reconstructed data show no significant deviation from the usual behavior observed in readers