A synthesis of long-term research by the Florida Coastal Everglades LTER Program

This paper synthesizes research conducted during the first 5–6 years of the Florida Coastal Everglades Long-Term Ecological Research Program (FCE LTER). My objectives are to review our research to date, and to present a new central theme and conceptual approach for future research. Our research has focused on understanding how dissolved organic matter (DOM) from upstream oligotrophic marshes interacted with a marine source of the limiting nutrient, phosphorus (P), to control productivity in the oligohaline estuarine ecotone. We have been working along freshwater to marine transects in two drainage basins located in Everglades National Park (ENP). The Shark River Slough transect (SRS) has a direct connection to the Gulf of Mexico, providing this estuarine ecotone with a source of marine P. The oligohaline ecotone along our southern Everglades transect (TS/Ph), however, is separated from this marine P source by the Florida Bay estuary. We originally hypothesized an ecosystem productivity peak in the SRS ecotone, driven by the interaction of marine P and Everglades DOM, but no such productivity peak in the TS/Ph ecotone because of this lack of marine P. Our research to date has tended to show the opposite pattern, however, with many ecosystem components showing enhanced productivity in the TS/Ph ecotone, but not in the SRS ecotone. Water column P concentrations followed a similar pattern, with unexpectedly high P in the TS/Ph ecotone during the dry season. Our organic geochemical research has shown that Everglades DOM is more refractory than originally hypothesized. We have also begun to understand the importance of detrital organic matter production and transport to ecotone dynamics and as the base of aquatic food webs. Our future research will build on this substantial body of knowledge about these oligotrophic estuaries. We will direct our efforts more strongly on biophysical dynamics in the oligohaline ecotone regions. Specifically, we will be focusing on inputs to these regions from four primary water sources: freshwater Everglades runoff, net precipitation, marine inputs, and groundwater. We are hypothesizing that dry season groundwater inputs of P will be particularly important to TS/Ph ecotone dynamics because of longer water residence times in this area. Our organic geochemical, biogeochemical, and ecosystem energetics work will focus more strongly on the importance of detrital organics and will take advantage of a key Everglades Restoration project, scheduled for 2008 or 2009, that will increase freshwater inputs to our SRS transect only. Finally, we will also begin to investigate the human dimensions of restoration, and of a growing population in south Florida that will become increasingly dependent on the Everglades for critical ecosystem services (including fresh water) even as its growth presents challenges to Everglades sustainability.

An Examination of the Validity of English Language Achievement Test Scores in a LEP Student Population

Approximately 1,700 limited English proficient (LEP) and recently exited LEP students in grades 4 and 10 were tested using both an English and a comparable Spanish language achievement test. Many LEP and former LEP students performed better in math taking the test in Spanish compared to taking it in English.

The influence of neighbourhood formality status and socio-economic position on self-rated health among adult men and women: a multilevel, cross sectional, population study from Aleppo, Syria

Background There is substantial evidence from high income countries that neighbourhoods have an influence on health independent of individual characteristics. However, neighbourhood characteristics are rarely taken into account in the analysis of urban health studies from developing countries. Informal urban neighbourhoods are home to about half of the population in Aleppo, the second largest city in Syria (population>2.5 million). This study aimed to examine the influence of neighbourhood socioeconomic status (SES) and formality status on self-rated health (SRH) of adult men and women residing in formal and informal urban neighbourhoods in Aleppo. Methods The study used data from 2038 survey respondents to the Aleppo Household Survey, 2004 (age 18–65 years, 54.8% women, response rate 86%). Respondents were nested in 45 neighbourhoods. Five individual-level SES measures, namely education, employment, car ownership, item ownership and household density, were aggregated to the level of neighbourhood. Multilevel regression models were used to investigate associations. Results We did not find evidence of important SRH variation between neighbourhoods. Neighbourhood average of household item ownership was associated with a greater likelihood of reporting excellent SRH in women; odds ratio (OR) for an increase of one item on average was 2.3 (95% CI 1.3-4.4 (versus poor SRH)) and 1.7 (95% CI 1.1-2.5 (versus normal SRH)), adjusted for individual characteristics and neighbourhood formality. After controlling for individual and neighbourhood SES measures, women living in informal neighbourhoods were less likely to report poor SRH than women living in formal neighbourhoods (OR= 0.4; 95% CI (0.2- 0.8) (versus poor SRH) and OR=0.5; 95%; CI (0.3-0.9) (versus normal SRH). Conclusions Findings support evidence from high income countries that certain characteristic of neighbourhoods affect men and women in different ways. Further research from similar urban settings in developing countries is needed to understand the mechanisms by which informal neighbourhoods influence women’s health.

Research Note: Biometric Technology Applications and Trends in Hotels

The purpose of this study is to investigate the biometrics technologies adopted by hotels and the perception of hotel managers toward biometric technology applications. A descriptive, cross sectional survey was developed based on extensive review of literature and expert opinions. The population for this survey was property level executive managers in the U.S. hotels. Members of American Hotel and Lodging Association (AHLA) were selected as the target population for this study. The most frequent use of biometric technology is by hotel employees in the form of fingerprint scanning. Cost still seems to be one of the major barriers to adoption of biometric technology applications. The findings of this study showed that there definitely is a future in using biometric technology applications in hotels in the future, however, according to hoteliers; neither guests nor hoteliers are ready for it fully.

Population viability analyses of Chamaecrista keyensis (Leguminosae: Caesalpinioideae), a narrowly endemic herb of the lower Florida Keys: Effects of seasonal timing of fires and the urban -wildland interface

This research first evaluated the effects of urban wildland interface on reproductive biology of the Big Pine Partridge Pea, Chamaecrista keyensis, an understory herb that is endemic to Big Pine Key, Florida. I found that C. keyensis was self-compatible, but depended on bees for seed set. Furthermore, individuals of C. keyensis in urban habitats suffered higher seed predation and therefore set fewer seeds than forest interior plants. ^ I then focused on the effects of fire at different times of the year, summer (wet) and winter (dry), on the population dynamics and population viability of C. keyensis. I found that C. keyensis population recovered faster after winter burns and early summer burns (May–June) than after late summer burns (July–September) due to better survival and seedling recruitment following former fires. Fire intensity had positive effects on reproduction of C. keyensis. In contrast, no significant fire intensity effects were found on survival, growth, and seedling recruitment. This indicated that better survival and seedling recruitment following winter and early summer burns (compared with late summer burns) were due to the reproductive phenology of the plant in relation to fires rather than differences in fire intensity. Deterministic population modeling showed that time since fire significantly affected the finite population growth rates (λ). Particularly, recently burned plots had the largest λ. In addition, effects of timing of fires on λ were most pronounced the year of burn, but not the subsequent years. The elasticity analyses suggested that maximizing survival is an effective way to minimize the reduction in finite population growth rate the year of burn. Early summer fires or dry-season fires may achieve this objective. Finally, stochastic simulations indicated that the C. keyensis population had lower extinction risk and population decline probability if burned in the winter than in the late summer. A fire frequency of approximately 7 years would create the lowest extinction probability for C. keyensis. A fire management regime including a wide range of burning seasons may be essential for the continued existence of C. keyensis and other endemic species of pine rockland on Big Pine Key. ^

A relationship between the Florida Comprehensive Assessment Test 2.0 mathematics scores and racial and ethnic concentration when considering socio-economic status, ESOL student population, and school climate

From the moment children are born, they begin a lifetime journey of learning about themselves and their surroundings. With the establishment of the No Child Left Behind Act of 2001, it mandates that all children receive a high-quality education in a positive school climate. Regardless of the school the child attends or the neighborhood in which the child lives, proper and quality education and resources must be provided and made available in order for the child to be academically successful. The purpose of this ex post facto study was to investigate the relationship between the FCAT 2.0 mathematics scores of public middle school students in Miami-Dade County, Florida and the concentrations of a school's racial and ethnic make-up (Whites, Blacks, and Hispanics), English for Speakers of other Languages (ESOL) population, socio-economic status (SES), and school climate. The research question of this study was: Is there a significant relationship between the FCAT 2.0 Mathematics scores and racial and ethnic concentration of public middle school students in Miami-Dade County when controlling SES, ESOL student population, and school climate for the 2010-2011 school year? The instruments used to collect the data were the FCAT 2.0 and Miami-Dade County Public Schools (M-DCPS) School Climate Survey. The study found that Economically Disadvantaged (SES) students socio-economic status had the strongest correlation with the FCAT 2.0 mathematics scores (r = -.830). The next strongest correlation was with the number of students who agreed that their school climate was positive and helped them learn (r = .741) and the third strongest correlation was a school percentage of White students (r = .668). The study concluded that the FCAT 2.0 mathematics scores of M-DCPS middle school students have a significant relationship with socio-economic status, school climate, and racial concentration.

Evaluating Effects of Everglades Restoration on American Crocodile Populations in South Florida Using a Spatially-Explicit, Stage-Based Population Model

The distribution and abundance of the American crocodile (Crocodylus acutus) in the Florida Everglades is dependent on the timing, amount, and location of freshwater flow. One of the goals of the Comprehensive Everglades Restoration Plan (CERP) is to restore historic freshwater flows to American crocodile habitat throughout the Everglades. To predict the impacts on the crocodile population from planned restoration activities, we created a stage-based spatially explicit crocodile population model that incorporated regional hydrology models and American crocodile research and monitoring data. Growth and survival were influenced by salinity, water depth, and density-dependent interactions. A stage-structured spatial model was used with discrete spatial convolution to direct crocodiles toward attractive sources where conditions were favorable. The model predicted that CERP would have both positive and negative impacts on American crocodile growth, survival, and distribution. Overall, crocodile populations across south Florida were predicted to decrease approximately 3 % with the implementation of CERP compared to future conditions without restoration, but local increases up to 30 % occurred in the Joe Bay area near Taylor Slough, and local decreases up to 30 % occurred in the vicinity of Buttonwood Canal due to changes in salinity and freshwater flows.

The Roles of Large Top Predators in Coastal Ecosystems: New Insights from Long Term Ecological Research

During recent human history, human activities such as overhunting and habitat destruction have severely impacted many large top predator populations around the world. Studies from a variety of ecosystems show that loss or diminishment of top predator populations can have serious consequences for population and community dynamics and ecosystem stability. However, there are relatively few studies of the roles of large top predators in coastal ecosystems, so that we do not yet completely understand what could happen to coastal areas if large top predators are extirpated or significantly reduced in number. This lack of knowledge is surprising given that coastal areas around the globe are highly valued and densely populated by humans, and thus coastal large top predator populations frequently come into conflict with coastal human populations. This paper reviews what is known about the ecological roles of large top predators in coastal systems and presents a synthesis of recent work from three coastal eastern US Long Term Ecological Research (LTER) sites where long-term studies reveal what appear to be common themes relating to the roles of large top predators in coastal systems. We discuss three specific themes: (1) large top predators acting as mobile links between disparate habitats, (2) large top predators potentially affecting nutrient and biogeochemical dynamics through localized behaviors, and (3) individual specialization of large top predator behaviors. We also discuss how research within the LTER network has led to enhanced understanding of the ecological roles of coastal large top predators. Highlighting this work is intended to encourage further investigation of the roles of large top predators across diverse coastal aquatic habitats and to better inform researchers and ecosystem managers about the importance of large top predators for coastal ecosystem health and stability.

Obesity, cardiovascular disease risk factors and weight loss in a population of adult Mexican Americans

The study of obesity has evolved into one of the most important public health issues in the United States (U.S.), particularly in Hispanic populations. Mexican Americans, the largest Hispanic ethnic subgroup in the U.S., have been significantly impacted by obesity and related cardiovascular diseases. Mexican Americans living in the Lower Rio Grande Valley (the Valley) in the Texas-Mexico border are one of the most disadvantaged and hard-to-reach minority groups. Demographic factors, socioeconomic status, acculturation, and physical activity behavior have been found to be important predictors of health, although research findings are mixed when establishing predictors of obesity in this population. Furthermore, while obesity has long been linked to cardiovascular disease (CVD) risk factors such as hypertension, type 2 diabetes, and dyslipidemia; information on the relationships between obesity and these CVD risk factors have been mostly from non-minority population groups. Overall, research has been mixed in establishing the association between obesity and related CVD risk factors in this population calling attention to the need for further research. Nevertheless, identifying predictors of success for weight loss in this population will be important if health disparities are to be addressed. The overall objective of the findings presented in this dissertation was to attain a more informed profile of obesity and CVD risk factors in this population. In particular, we examined predictors of obesity, measures of obesity and association with cardiovascular disease risk factors in a sample of 975 Mexican Americans participating in a health promotion program in the Valley region. Findings suggest acculturation factors to be one of the most important predictors of obesity in this population. Results also point to the need of identifying other possible risk factors for predicting CVD risk. Finally, initial body mass index is an important predictor of weight loss in this population group. Thus, indicating that this population is not only amenable to change, but that improvements in weight loss are feasible. This finding strengthens the relevance of prevention programs such as Beyond Sabor for Mexican populations at risk, in particular, food bank recipients.

Tree Islands in Everglades Landscapes: Current Status, Historical Changes, and Hydrologic Impacts on Population Dynamics and Moisture Relations, First Annual Report

In 2005 we initiated a project designed to better understand tree island structure and function in the Everglades and the wetlands bordering it. Focus was on the raised portions at the upstream end of the islands, where tropical hardwood species adapted to well-drained conditions usually are the most prominent component of the vegetation. The study design is hierarchical, with four levels; in general, a large number of sites is to be surveyed once for a limited set of parameters, and increasingly small sets of islands are to be sampled more intensively, more frequently, and for more aspects of ecosystem function. During the first year of the 3-year study, we completed surveys of 41 Level 1 (i.e., the least intensive level) islands, and established permanent plots in two and three islands of Levels 2 and 4 intensity, respectively. Tree species richness and structural complexity was highest in Shark Slough “hammocks”, while islands in Northeast Shark Slough and Water Conservation Area 3B, which receive heavy human use, were simpler, more park-like communities. Initial monitoring of soil moisture in Level 4 hammocks indicated considerable local variation, presumably associated with antecedent rainfall and current water levels in the adjacent marsh. Tree islands throughout the study area were impacted significantly by Hurricanes Katrina and Wilma in 2005, but appear to be recovering rapidly. As the project continues to include more islands and repeated measurements, we expect to develop a better grasp of tree island dynamics across the Everglades ecosystem, especially with respect to moisture relations and water levels in the adjacent marsh. The detailed progress report which follows is also available online at http://www.fiu.edu/~serp1/projects/treeislands/tree_islands_2005_annual_report.pd

Monitoring of Tree Island Conditions in the Southern Everglades: The Effects of Hurricanes and Hydrology on the Status and Population Dynamics of Sixteen Tropical Hardwood Hammock Tree Islands

In 2005 we began a multi-year intensive monitoring and assessment study of tropical hardwood hammocks within two distinct hydrologic regions in Everglades National Park, under funding from the CERP Monitoring and Assessment Program. In serving as an Annual Report for 2010, this document, reports in detail on the population dynamics and status of tropical hardwood hammocks in Shark Slough and adjacent marl prairies during a 4-year period between 2005 and 2009. 2005-09 was a period that saw a marked drawdown in marsh water levels (July 2006 - July 2008), and an active hurricane season in 2005 with two hurricanes, Hurricane Katrina and Wilma, making landfall over south Florida. Thus much of our focus here is on the responses of these forests to annual variation in marsh water level, and on recovery from disturbance. Most of the data are from 16 rectangular permanent plots of 225-625 m2 , with all trees mapped and tagged, and bi-annual sampling of the tree, sapling, shrub, and herb layer in a nested design. At each visit, canopy photos were taken and later analyzed for determination of interannual variation in leaf area index and canopy openness. Three of the plots were sampled at 2-month intervals, in order to gain a better idea of seasonal dynamics in litterfall and litter turnover. Changes in canopy structure were monitored through a vertical line intercept method.

The response to an ESL population boom in the Beaufort County, South Carolina school system: A case study

The purpose of this case study was to examine the why the English language learners (ELLs) in the Beaufort County, South Carolina school system have been so successful. This school system has recently experienced a boom in its ESL student population, and this population has performed very well on standardized tests. This study used critical theory as its theoretical framework and examined why the students have been successful rather than marginalized in Beaufort County schools. This phenomenon was investigated using semi-structured interviews with the ESOL Coordinator for Beaufort County, 4 ESL-lead teachers, and 6 mainstream teachers.^ Data were collected using semi-structured interviews with Sarah Owen, the Beaufort County ESOL, Gifted and Talented, and World Languages coordinator. Based on the results of her interview, 4 themes emerged that were used for the semi-structured interviews with ESOL and mainstream teachers. The interviews centered on the themes of ESL policy, ESL leadership, and teacher training. The ESL and mainstream teacher interviews also revealed several subthemes that included teacher attitude, why Beaufort County has been successful with the ELLs, and the teachers' recommendations for other schools systems trying to successfully accommodate a large ESL student population in mainstream classrooms. ^ The findings from the teachers' interviews revealed that additional training for the teachers without ESL experience helped them become comfortable instructing ELLs. This training should be conducted by the ESOL teachers for those without ESOL certification or endorsement. As the teachers had more training, they had better attitudes about teaching ESOL students in their classes. Finally, those who utilized the additional ESOL training and ESOL accommodations saw better student achievement in their classes.^ Based on the finding of this study, the researcher proposed a model for other school systems to follow in order to replicate the success of Beaufort County's ELLs. The implications of this study focus on other schools systems and why ELLs are not obtaining the same level of success as those in Beaufort County's schools. Finally, recommendations for further research are provided.^

A study to identify the nutritional problems in the elementary school population in the Republic of Venezuela

The purpose of this research is to identify and evaluate the nutritional problems that exist in the student population at the elementary school level in the Republic of Venezuela and to develop a system that will make it possible to deliver a more adequate diet to this population, with a greater fulfillment of their nutritional needs.

Obesity, Cardiovascular Risk Factors, and Weight Loss in a Population of Adult Mexican Americans

The study of obesity has evolved into one of the most important public health issues in the United States (U.S.), particularly in Hispanic populations. Mexican Americans, the largest Hispanic ethnic subgroup in the U.S., have been significantly impacted by obesity and related cardiovascular diseases. Mexican Americans living in the Lower Rio Grande Valley (the Valley) in the Texas-Mexico border are one of the most disadvantaged and hard-to-reach minority groups. Demographic factors, socioeconomic status, acculturation, and physical activity behavior have been found to be important predictors of health, although research findings are mixed when establishing predictors of obesity in this population. Furthermore, while obesity has long been linked to cardiovascular disease (CVD) risk factors such as hypertension, type 2 diabetes, and dyslipidemia; information on the relationships between obesity and these CVD risk factors have been mostly from non-minority population groups. Overall, research has been mixed in establishing the association between obesity and related CVD risk factors in this population calling attention to the need for further research. Nevertheless, identifying predictors of success for weight loss in this population will be important if health disparities are to be addressed. The overall objective of the findings presented in this dissertation was to attain a more informed profile of obesity and CVD risk factors in this population. In particular, we examined predictors of obesity, measures of obesity and association with cardiovascular disease risk factors in a sample of 975 Mexican Americans participating in a health promotion program in the Valley region. Findings suggest acculturation factors to be one of the most important predictors of obesity in this population. Results also point to the need of identifying other possible risk factors for predicting CVD risk. Finally, initial body mass index is an important predictor of weight loss in this population group. Thus, indicating that this population is not only amenable to change, but that improvements in weight loss are feasible. This finding strengthens the relevance of prevention programs such as Beyond Sabor for Mexican populations at risk, in particular, food bank recipients.

The Response to an ESL Population Boom in the Beaufort County, South Carolina School System: A Case Study

The purpose of this case study was to examine the why the English language learners (ELLs) in the Beaufort County, South Carolina school system have been so successful. This school system has recently experienced a boom in its ESL student population, and this population has performed very well on standardized tests. This study used critical theory as its theoretical framework and examined why the students have been successful rather than marginalized in Beaufort County schools. This phenomenon was investigated using semi-structured interviews with the ESOL Coordinator for Beaufort County, 4 ESL-lead teachers, and 6 mainstream teachers. Data were collected using semi-structured interviews with Sarah Owen, the Beaufort County ESOL, Gifted and Talented, and World Languages coordinator. Based on the results of her interview, 4 themes emerged that were used for the semi-structured interviews with ESOL and mainstream teachers. The interviews centered on the themes of ESL policy, ESL leadership, and teacher training. The ESL and mainstream teacher interviews also revealed several subthemes that included teacher attitude, why Beaufort County has been successful with the ELLs, and the teachers’ recommendations for other schools systems trying to successfully accommodate a large ESL student population in mainstream classrooms. The findings from the teachers’ interviews revealed that additional training for the teachers without ESL experience helped them become comfortable instructing ELLs. This training should be conducted by the ESOL teachers for those without ESOL certification or endorsement. As the teachers had more training, they had better attitudes about teaching ESOL students in their classes. Finally, those who utilized the additional ESOL training and ESOL accommodations saw better student achievement in their classes. Based on the finding of this study, the researcher proposed a model for other school systems to follow in order to replicate the success of Beaufort County’s ELLs. The implications of this study focus on other schools systems and why ELLs are not obtaining the same level of success as those in Beaufort County’s schools. Finally, recommendations for further research are provided.