Physical limitations in meal preparation and consumption are associated with lower musculoskeletal nutrient (calcium, vitamin D, magnesium, and phosphorus) intakes in homebound older adults.

OBJECTIVES: Although homebound older adults are at increased risk for poor nutritional health and adverse nutrition-related outcomes, little attention has focused on the tasks involved in meal preparation and consumption and the influence of those tasks on dietary intake. METHODS: We examined the self-reported dietary intake from 3, 24-h dietary recalls and physical limitations in meal preparation and consumption (LMPC) activities from a randomly recruited sample of 345 homebound older men and women. Ordered logistic regression was used to examine the correlation of demographic characteristics and 6 activities with relative intakes of key musculoskeletal nutrients (calcium, vitamin D, magnesium, and phosphorus). RESULTS: At least 70% reported not meeting ⅔ recommended intakes for calcium and vitamin D; 12.5% failed to achieve ⅔ recommended intakes in at least three of the four nutrients. More than 12% of the sample reported it was very difficult or they were unable to perform at least 3 LMPC tasks. Regression results indicated that reporting the greatest LMPC increased the odds for lower intake of musculoskeletal nutrients. CONCLUSION: Independent of sociodemographic characteristics, self-reported difficulty in meal preparation and consumption was associated with lower dietary intakes of musculoskeletal nutrients. These results suggest the need to assess difficulty in meal preparation and consumption for the growing population of homebound older adults who participate in supplemental nutrition programs. This brief, 6-item measure may help identify older adults at risk of poor nutritional health and declining function.

Where, why, and to what extent have rangelands in the Karoo, South Africa, desertified.

We used simple questionnaire surveys to obtain rough categorical information on the status of semiarid and arid rangelands in the Karoo, South Africa. We sent questionnaires to extension officers of the Department of Agricultural Development, asking them to rank the condition of the rangeland in their extension districts (usually about 500 farms) on a three- or five-point scale. The questionnaire also sought information on the possible reasons for changes in the condition of the rangelands; vegetation types most at risk on mismanaged rangelands; and changes in the status of plants, birds, and mammals. Extension officers rated 35% of the semiarid rangelands in southwestern South Africa (the Karoo and southern Kalahari Desert) as being in poor condition. There was some congruency between the perceived condition of the agricultural extension district and the percentage that the stocking rate had decreased. Rangeland condition in more arid areas tends to be poor. Stocking rates have decreased disproportionately more in arid areas than in the more mesic areas of southwestern South Africa. Grasses were rated as the most threatened group of plants, and succulents the least threatened group. Overgrazing in the past was considered to be the most important cause of present-day rangeland condition, followed by present overstocking of rangelands. Antelope were considered more threatened by rangeland management than mammalian carnivores. Avian raptors and bustards, gamebirds, and tortoises were all perceived to be threatened by rangeland mismanagement.

South Africa's arid and semiarid rangelands: Why are they changing and can they be restored?

Since the mid-19th century settled livestock ranching has been the major form of land use in South Africa, occupying 68% of the land surface. Decreases in livestock densities and ranch numbers during the past century imply that carrying capacities for domestic herbivores are falling. Differences in carbon isotope signals with soil depth and abrupt shifts in dominant plant species across ranch boundaries reveal that southern African rangelands are changing. Case studies suggest ways to control altered grassland composition, bush encroachment in arid savanna, and dominance by toxic and halophytic shrubs in arid shrublands. But climatic and biological factors constrain rates of passive recovery, and guidelines for active restoration are poor and techniques costly. Moreover, conservation of remaining good rangeland is seldom enforced, and economic considerations usually outweight the land user's desire to sustain diversity and productivity.

An underground index of rangeland degradation: cicadas in arid southern Africa.

The prediction that density of long-lived, underground herbivores (Cicadidae) is a function of rangeland condition was examined in arid shrublands in the Karoo, South Africa. It was found that the density of adult cicadas was correlated with cover of deep-rooted, perennial plants. Differences in perennial plant cover were independent of soil type and rock cover. On degraded rangelands, where perennial plants had been replaced by ephemerals and short-lived plants, cicada densities were significantly depressed. We concluded that vegetation transformation by domestic livestock is likely to affect invertebrate populations and their vertebrate predators.

Evidence for rapid faunal changes on islands in a man-made lake : I. Ants.

Few studies of island biogeography have been made on islands in which the time of insularization is precisely known. We tested the effects of island formation on ant species diversity in a man-made lake in South Africa, to determine whether island effects are detectable after only 16 years of insularization. The number of ant species observed at trap-line censuses on islands was significantly correlated with island size (r=0.608; P<0.05) and ant species diversity was generally low compared with similar mainland habitats. Mean species number for all islands, including landbridge islands, was 5.5±3.3 species, and on mainland sites was 7.9±2.85 species. Island effects were more marked on islands <20 ha, which had a mean of 3.3±2.5 species per island. Species number on islands was inversely related to densities of the aggressive Anoplolepis custodiens and A. steingroeveri. These two species were only patchily distributed on mainlands, but these ants were nearly ubiquitous on small islands. Several lines of evidence suggest that this single species domination may be responsible for island effects. Island sites also differed in the number of ant species in different trophic groupings, tending to have fewer granivorous species than the mainland sites, but species in other diet groups were similar in both island and mainland habitats. We conclude that there have been marked changes in the ant faunas on islands smaller than 20 ha apparently due to changes in abundance of the dominant ant species. However, the causes of these changes are unknown.