A molecular and stable isotopic approach to investigate the importance of algal and detrital energy pathways in a freshwater marsh

The relative importance of algal and detrital energy pathways remains a central question in wetlands ecology. We used bulk stable isotope analysis and fatty acid composition to investigate the relative contributions of periphyton (algae) and floc (detritus) in a freshwater wetland with the goal of determining the inputs of these resource pools to lower trophic-level consumers. All animal samples revealed fatty acid markers indicative of both microbial (detrital) and algal origins, though the relative contributions varied among species. Vascular plant markers were in low abundance in most consumers. Detritivory is important for chironomids and amphipods, as demonstrated by the enhanced bacterial fatty acids present in both consumers, while algal resources, in the form of periphyton, likely support ephemeropteran larvae. Invertebrates such as amphipods and grass shrimp appear to be important resources for small omnivorous fish, while Poecilia latipinna appear to strongly use periphyton and Ephemeroptera larvae as food sources. Both P. latipinna and Lepomis spp. assimilated small amounts of vascular plant debris, possibly due to unintentional ingestion of floc while foraging for invertebrates and insect larvae. Physid snails, Haitia spp., were characterized by considerably different fatty acid compositions than other taxa examined, and likely play a unique role in Everglades’ food webs.

A preliminary analysis of the correlation of food-web characteristics with hydrology and nutrient gradients in the southern Everglades

We estimated trophic position and carbon source for three consumers (Florida gar, Lepisosteus platyrhincus; eastern mosquitofish, Gambusia holbrooki; and riverine grass shrimp, Palaemonetes paludosus) from 20 sites representing gradients of productivity and hydrological disturbance in the southern Florida Everglades, U.S.A. We characterized gross primary productivity at each site using light/dark bottle incubation and stem density of emergent vascular plants. We also documented nutrient availability as total phosphorus (TP) in floc and periphyton, and the density of small fishes. Hydrological disturbance was characterized as the time since a site was last dried and the average number of days per year the sites were inundated for the previous 10 years. Food-web attributes were estimated in both the wet and dry seasons by analysis of δ15N (trophic position) and δ13C (food-web carbon source) from 702 samples of aquatic consumers. An index of carbon source was derived from a two-member mixing model with Seminole ramshorn snails (Planorbella duryi) as a basal grazing consumer and scuds (amphipods Hyallela azteca) as a basal detritivore. Snails yielded carbon isotopic values similar to green algae and diatoms, while carbon values of scuds were similar to bulk periphyton and floc; carbon isotopic values of cyanobacteria were enriched in C13compared to all consumers examined. A carbon source similar to scuds dominated at all but one study site, and though the relative contribution of scud-like and snail-like carbon sources was variable, there was no evidence that these contributions were a function of abiotic factors or season. Gar consistently displayed the highest estimated trophic position of the consumers studied, with mosquitofish feeding at a slightly lower level, and grass shrimp feeding at the lowest level. Trophic position was not correlated with any nutrient or productivity parameter, but did increase for grass shrimp and mosquitofish as the time following droughts increased. Trophic position of Florida gar was positively correlated with emergent plant stem density.

Recruiting and developing technicians for hotel food service operations

The thesis which follows is a study of recruiting and developing skilled workers for Hotel Food Service Operations in the Miami area. The aim of the study is to bring to the attention of personnel management the role of recruiting and training in providing the skilled people needed for their operation in the short and long run as well. The study was done as a case study of the medium and large size hotels which have a minimum of 250 units each in the Miami area. However, the study has been generalized where it is possible, and when data permitted. The primary data was collected by the use of the questionnaire survey method composed of key questions about recruiting, training and sources of skilled people, turnover reasons, etc. Eight tables have been constructed, analyzed and interpreted. A personal opinion was mentioned in the interpretation of each table's data. It was found that personnel management should provide a better recruiting and developing procedures in order to attract more qualified people, particularly among the youngsters who are potential skilled workers for the future. It was concluded that the quality of work life, the benefits, and the opportunities for advancement in the food and beverage operations play a significant role in an employee's decision to stay with a particular job, and to acquire the necessary skills.

Sources of nutrition information for persons living in Trinidad and Tobago

Health consumers worldwide obtain nutrition information from various sources; however, the sources Trinidadians and Tobagonians accessed were unclear. This cross-sectional, descriptive study ascertained from which sources Trinidadians and Tobagonians obtained nutrition information. Participants (n = 845) were surveyed with questions regarding demographics and nutrition information sources. Nearly 100% agreed nutrition information was important. Persons 18-64 years old mainly accessed print media (p<0.01) and ≥ 65years old predominantly accessed the non-print media. Significantly more tertiary educated people, ≥ 35 years old, retrieved information from print media (p=0.001), health care professionals (p=0.001), food labels (p=0.006), and non-print media (p=0.03) when compared to those < 35 years with similar education. Tertiary educated people (67%), selected the Internet when compared to those with without tertiary education (33%) (p<0.001). Knowing the nutrition information sources accessed, dietitians will be able to provide consistent, accurate, age specific nutrition information and promote healthy eating among Trinidadians and Tobagonians.