Historic primary producer communities linked to water quality and hydrologic changes in the northern Everglades

The northern Everglades Water Conservation Areas have experienced recent ecological shifts in primary producer community structure involving marl periphyton mats and dense Typha-dominated macrophyte stands. Multiple investigations have identified phosphorus (P) as a driver of primary producer community structure, but effects of water impoundment beginning in the 1950s and changes in water hardness [e.g., (CaCO3)] have also been identified as a concern. In an effort to understand pre-1950, primary producer community structure and identify community shifts since 1950, we measured pigment proxies on three sediment cores collected in Water Conservation Area-2A (WCA-2A) along a phosphorus enrichment gradient. Photosynthetic pigments, sediment total phosphorus content (TP), organic matter, total organic carbon and nitrogen were used to infer historic primary producer communities and changes in water quality and hydrology regulating those communities. Excess 210Pb was used to establish historic dates for the sediment cores. Results indicate the northern area of WCA-2A increased marl deposition and increased algal abundance ca. 1920. This increase in (presumably) calcareous periphyton before intensive agriculture and impoundment suggest canal-derived calcium inputs and to some extent early drainage effects played a role in initiating this community shift. The northern area community then shifted to Typha dominance around 1965. The areas to the south in WCA-2A experienced increased marl deposition and algal abundance around or just prior to 1950s impoundment, the precise timing limited by core age resolution. Continued increases in algal abundance were evident after 1950, coinciding with impoundment and deepening of canals draining into WCA-2A, both likely increasing water mineral and nutrient concentrations. The intermediate site developed a Typha-dominated community ca. 1995 while the southern-most core site WCA-2A has yet to develop Typha dominance. Numerous studies link sediment TP >650 mg P/kg to marsh habitat degradation into Typha-dominance. The northern and intermediate cores where Typha is currently support this previous research by showing a distinct shift in the sediment record to Typha dominance corresponding to sediment TP between 600 and 700 mg P/kg. These temporal and spatial differences are consistent with modern evidence showing water-column gradients in mineral inputs (including Ca, carbonates, and phosphorus) altering primary producer community structure in WCA-2A, but also suggest hydroperiod has an effect on the mechanisms regulating periphyton development and Typha dominance.

The early development and pilot -testing of a case management intervention with victims of stalking: An evaluation study

This study evaluated the early development and pilot-testing of Project IMPACT, a case management intervention for victims of stalking. The Design and Development framework (Rothman & Thomas, 1994) was used as a guide for program development and evaluation. Nine research questions examined the processes and outcomes associated with program implementation. ^ The sample included all 36 clients who participated in Project IMPACT between February of 2000 and June of 2001, as well as the victim advocates who provided them with services. Quantitative and qualitative data were drawn from client case files, participant observation field notes and interview transcriptions. Quantitative data were entered into three databases where: (1) clients were the units of analysis (n = 36), (2) services were the units of analysis (n = 1146), and (3) goals were the units of analysis (n = 149). These data were analyzed using descriptive statistics, Pearson's Chi-square, Spearman's Rho, Phi, Cramer's V, Wilcoxon's Matched Pairs Signed-Ranked Test and McNemar's Test Statistic. Qualitative data were reduced via open, axial and selective coding methods. Grounded theory and case study frameworks were utilized to analyze these data. ^ Results showed that most clients noted an improved sense of well-being and safety, although residual symptoms of trauma remained for numerous individuals. Stalkers appeared to respond to criminal and civil justice-based interventions by reducing violent and threatening behaviors; however, covert behaviors continued. The study produced findings that provided preliminary support for the use of several intervention components including support services, psycho-education, safety planning, and boundary spanning. The psycho-education and safety planning in particular seemed to help clients cognitively reframe their perceptions of the stalking experience and gain a sense of increased safety and well-being. A 65% level of satisfactory goal achievement was observed overall, although goals involving justice-based organizations were associated with lower achievement. High service usage was related to low-income clients and those lacking in social support. Numerous inconsistencies in program implementation were found to be associated with the skills and experiences of victim advocates. Thus, recommendations were made to further refine, develop and evaluate the intervention. ^