Elements in autopsy liver tissue samples from Greenlandic inuit and Danes. V. Selenium measured by X-ray fluorescence spectrometry

The content of selenium in normal liver tissue samples from Greenlandic Inuit was measured and the results compared with those obtained in normal liver tissue samples from Danes. Normal liver tissue samples were obtained at autopsy from 50 Greenlandic Inuit (27 men, 23 women) with a median age of 61 years (range 23–83) and from 74 Danes (44 men, 30 women) with a median age of 60 years (range 15–87). Total liver selenium content was measured by X-ray fluorescence spectrometry. The content of selenium (median) was in Inuit 26.6 mol/kg dry liver (5–95 percentile: 15.2–49.4) and in Danes 17.7 mol/kg dry liver (5–95 percentile: < 3.8–36.5) (p < 0.0001). Liver selenium content displayed no significant gender difference, either in Inuit or Danes. In Inuit men, there was a negative correlation between liver selenium content and age (r_s = −0.39, p < 0.05), whereas Danish men displayed a positive correlation between liver selenium content and age (r_s = 0.37, p = 0.02). There was no correlation in Inuit or Danish women. In Inuit, the median hepatic selenium index (liver selenium content divided by age) was 0.48 and in Danes 0.33 (p = 0.001). There was an inverse correlation between hepatic selenium index and age both in Inuit (r_s = −0.77, p < 0.0001) and in Danes (r_s = −0.47, p < 0.0001). In conclusion, Inuit had a higher liver content of selenium and a higher hepatic selenium index compared with Danes. The more favourable selenium status is due to a higher nutritional selenium intake with fish and meat from sea mammals.     

Medicinal Plant Knowledge Among Lay People in Five Eastern Tibet Villages

Tibetans in five villages in the Mount Khawa Karpo area of the Menri (Meili Xueshan in Chinese) range, Northwest Yunnan, People’s Republic of China, were interviewed about their knowledge of a number of medicinal plants and their uses. There was large variation in people’s knowledge with significant differences among the villages and between men and women. Most of the reported knowledge focused on a small number of commercial plants and their uses. In comparison with Tibetan doctors, villagers generally knew fewer applications and focused on general health remedies. Many people collected medicinal plants for their own use as well as for sale, but also obtained medicinal plant remedies from markets and Tibetan doctors, and often used traditional Tibetan healthcare in conjunction with biomedical treatment.     

Diversity of palm uses in the western Amazon

We used palm knowledge to understand the interaction between people and the rainforests and the factors that influence this dynamic process. We interviewed 278 informants in 12 villages in the Pastaza and Madidi areas of the western Amazon basin. Together they used 38 different palm species for 38 different uses in six use-categories (food, construction, utensils, ritual, medicine, commercial). Euterpe precatoria, Iriartea deltoidea, and Oenocarpus bataua were best known and were mentioned as useful by 76–72% of the informants in the 12 villages. There was a great variation in number of uses and in how widespread the uses were and five of the 38 useful palms were mentioned by only one informant. Among the socioeconomic factors analyzed, the residence village influenced the informants’ knowledge of palms and their uses more than any other factor. Length of education, prosperity and for how long the informant had lived in the village were also positively correlated to how many palms and palm uses were known. Gender differences in informants’ knowledge of palm uses were not observed in our data. We suggest, that the high importance of forest products to the livelihood of the villagers, the great variation in the knowledge they possess, and the fact that the differences between villages is so great, are important elements to consider when developing management plans for the sustainable use of the rainforest resources in the western Amazon.     

Traditional knowledge ofDypsis Fibrosa (Arecaceae) in Eastern Madagascar

Dypsis fibrosa is widespread in eastern Madagascar and local people regard it as one of the most important palms due to its use as thatch. In an interview survey 12 different uses of this palm were reported. Most informants knew only one or two uses, but variance was large. How many uses people know and what they use different palm parts for is correlated to socioeconomic factors such as personal wealth and home village. Comparison of data obtained from interviews and observations showed that there is not always a strict correlation between ethnobotanical data elicited in surveys, actual extent of use, and importance accorded to different plant resources. Informants were generally aware of an human-caused decline inD. fibrosa abundance, but viewed it as inevitable and suggested to replaceD. fibrosa products by other materials. Although local people viewD. fibrosa as very important, motivation for its conservation and sustainable use seems to be low.     

Diversity and use of palms in Zahamena, eastern Madagascar

Madagascar's palm flora is very diverse (171 species) and has a high degree of endemism (97%). Palm products make an important contribution to the household economy of many rural families, especially in the palm-rich eastern escarpments. Many palms are, however, threatened by overexploitation and habitat destruction. We investigated which palm species were found and used in three villages on the eastern escarpments of Madagascar. The importance local people accorded to each species was compared to the number of its uses, number of people using it, and other aspects of its use. From this comparison it was concluded that even if important palms are used for more purposes than less important palms, they owe their importance to one or two of their main uses. We also investigated if there were any patterns in the distribution of informants' knowledge and whether such patterns could be related to socio-economic factors. There was a positive relationship between knowledge about palms and personal wealth and a negative relationship between distance to the forest and amount of knowledge. The latter can be a sign of an ongoing knowledge erosion. Sustainable use of native palms should be encouraged as it may contribute positively to village economy and knowledge preservation, and may provide incentives for preservation of remaining forest tracts.     

Influence of diversity and road access on palm extraction at landscape scale in SE Ecuador

The relationship between biodiversity and the activities of small-scale farmers remains poorly understood despite its importance for conservation. In tropical forest areas farmers often include extraction of forest products in their subsistence strategies, and it has been suggested that factors such as market access and diversity levels influence people’s use of forest products. To investigate these relationships, we studied the use of palms in five villages inhabited by colonists and indigenous Shuar in the lower montane forest in south-eastern Ecuador by means of interviews and line transects around the villages. We found that use of palms was not driven by the diversity of palms available in the forest surrounding each village. Instead, the most important factor seemed to be lack of market access so in villages furthest away from the nearest road people used more palm products for their subsistence life compared to villages closer to the road. Forests around more remote villages had higher utility levels when evaluated on the basis of the villagers’ use of palms, despite lower levels of palm diversity and richness in these forests. The lower diversity levels may reflect past human activity or ecological factors, or a combination of both. In either case, our results show that forests with higher diversity levels are not necessarily more valuable to local people compared to less diverse forests. Instead, socio-economic factors such as market access may be more important in shaping people’s relationship with the natural environment.     

Residue specific hydration of primary cell wall potato pectin identified by solid-state 13C single-pulse MAS and CP/MAS NMR spectroscopy

Hydration of rhamnogalacturonan-I (RG-I) derived from potato cell wall was analyzed by (13)C single-pulse (SP) magic-angle-spinning (MAS) and (13)C cross-polarization (CP) MAS nuclear magnetic resonance (NMR) and supported by (2)H SP/MAS NMR experiments. The study shows that the arabinan side chains hydrate more readily than the galactan side chains and suggests that the overall hydration properties can be controlled by modifying the ratio of these side chains. Enzymatic modification of native (NA) RG-I provided samples with reduced content of arabinan (sample DA), galactan (sample DG), or both side chains (sample DB). Results of these samples suggested that hydration properties were determined by the length and character of the side chains. NA and DA exhibited similar hydration characteristics, whereas DG and DB were difficult to hydrate because of the less hydrophilic properties of the rhamnose-galacturonic acid (Rha-GalA) backbone in RG-I. Potential food ingredient uses of RG-I by tailoring of its structure are discussed.     

A Temporal Dimension of Household Vulnerability in Three Rural Communities in Lijiang,China

We examine the dynamics of household vulnerability during the past 30 years within three different social-ecological upland systems in Lijiang, Yunnan. Interviews were conducted to construct coupled human-environmental timelines to facilitate the understanding of livelihood dynamics in the context of more general changes that constitute both constraints and opportunities. The results indicate that significant livelihood changes including specialization, diversification and migration have been primarily driven by socio-political influences. Overall vulnerability of households has decreased differently across villages. Nevertheless, climate change is a concern as households perceive increasing temperature, declining precipitation and unpredictable extreme events. In the future, households’ vulnerability might increase since important components of current livelihoods remain climate sensitive. Moreover, environmentally destructive practices such as illegal logging might reinforce the negative impacts of climate change and thus undermine sustainable adaptation.     

Traditional Knowledge,Use, and Management of <Emphasis Type="Italic">Aphandra natalia</Emphasis> (Arecaceae) in Amazonian Peru

Traditional Knowledge, Use, and Management of Aphandra natalia (Arecaceae) in Amazonian Peru. Along the Pastaza and Urituyacu rivers in Peru, 100 informants in four villages knew 17 different uses of the piassaba fiber palm, Aphandra natalia (Balslev and Henderson) Barfod. Human consumption of fruits, extraction of fibers for trade, and harvesting leaves for thatch were the most frequently reported uses. Twenty uses were documented previously in the literature, and eight are reported here for the first time. Knowledge concerning the use of A. natalia among villagers varied significantly with ethnicity, village, and gender, but not with education or age; Amerindian informants knew more than non-Amerindian informants, and men knew more than women. Old and young informants knew about the same numbers of uses, and those who had little formal school training knew as many as those who had attended school for a longer time. Although 44% of our informants knew about fiber extraction, trade involving Aphandra fibers was not of great economic importance in our study area. Because fiber extraction has been documented as the most important use in all previous studies of A. natalia, it was surprising to find that people in one of the studied villages did not use A. natalia for that purpose at all. In contrast to previous observations, the extraction of fibers involved the destructive felling of the palms. We recommend implementing non-destructive extraction techniques so that local communities could exploit the fiber resource in a sustainable way. Non-destructive extraction methods involve cutting leaves from standing palms instead of felling the entire tree and leaving a few leaves on each extracted palm. However, given the limited economic incentive to the extractor, market mechanisms may be the greatest barrier to implementing sustainable extraction techniques.