Leaf Litter Decomposition and Nutrient Dynamics in Four Southern Forested Floodplain Communities

Decomposition of site-specific litter mixtures was monitored for 100 wk in four Roodplaht communities: (i) a mixed oak community along the Cache River in central Arkansas, (ii) s sweetgum (Liquidambar styracijlua L.)-cherrybark oak (Quercus falcata var. pagodaefolia ELI.) community along Iatt Creek in central Louisiana, (iii) a sweetgum-swamp tupelo [Nyssa sylvatica var. biflora (Walt.) Sarg.] community, and (iv) a laurel oak (Quercus laurifolia Michx.) commnnityalong the Coosawhatchie River in southeastern South Carolina. Soil temperature, hydroperiod, and litter quality (C:N, C:P, N:P, fignin: N) were used to interpret differences in the rates of mass loss and nutrient dynamics. After 100 wk, litter mixtures retained 33, 18, 8, and 5% of original mass on the Cache, Coosawhatchie (laurel oak community), Coosawhatchie (sweetgum-swamp tupelo community), and Iatt floodplains, respectively, and these differences appeared related to hydroperiod. Decay rates were comparable to rates reportedin similar floodplain environments. Net mineralization of both N and P was observed after 100 wk, but both elements accumulated in litter mixtures periodically. Differences in hydroperiod were observed among the four floodplain communities and decomposition of and nutrient mineralization from litter among them appeared to be inversely related to the number and duration of flood events. Litterbags containing leaf litter of a single-species (i.e., cherrybark oak) were also monitored on three of the four sites to compare decay rates and nutrient dynamics with the litter mixtures. On the Cache River floodplain, slower decay of poorer quality cherrybark oak litter suggested that titter quality drove decomposition under similar edaphic conditions

Beliefs about AIDS in five Latin and Anglo-American populations: The role of the biomedical model

This paper focuses on variability in beliefs about AIDS among Latin Americans, as compared with middle class Americans. Four geographically dispersed groups of Latin Americans were chosen for study as well as a middle class, largely Anglo-American population. Coherent sets of beliefs were found at each site, and despite tremendous variability among the five populations, beliefs were remarkably similar across sites. The biomedical model is widely shared, and the critical variable in the extent to which it is understood is community prevalence of AIDS

Beliefs about AIDS in five Latin and Anglo-American populations: The role of the biomedical model

This paper focuses on variability in beliefs about AIDS among Latin Americans, as compared with middle class Americans. Four geographically dispersed groups of Latin Americans were chosen for study as well as a middle class, largely Anglo-American population. Coherent sets of beliefs were found at each site, and despite tremendous variability among the five populations, beliefs were remarkably similar across sites. The biomedical model is widely shared, and the critical variable in the extent to which it is understood is community prevalence of AIDS