The importance of catchments to mine-pit lakes: Implications for closure

Despite the large body of riparian literature for rivers and lakes, there are few studies on the catchments of mine pit lakes. Therefore, the broad objective of this research was to determine if catchment characteristics were related to pit lake nutrient concentrations. We hypothesised that: (1) catchment characteristics would vary among pit lakes, (2) pit lake catchments would differ from co-occurring naturally-forested catchments, and (3) connecting a pit lake (Kepwari) to a naturally-forested catchment via a river flow-through would increase C accumulation in the lake. The research was conducted in pit lakes of the Collie lake district in Western Australia and examined catchment characteristics (soil nutrients, litter biomass, vegetation, and biomass), carbon and sedimentation rates in pelagic and benthic materials, and establishment of a simple nutrient budget for Lake Kepwari. Broadly, results indicated that catchment vegetation differed significantly among pit lakes (although parts were similar to co-occurring natural forest), with differences largely driven by catchment age. None of the pit lake catchments had true riparian species surrounding the pit lakes. The hypothesis that connecting a pit lake to a watercourse would increase carbon concentrations and sedimentation was not supported. Most (87%) of the water that entered the lake was from the river, and river outflow was slightly greater than river inflow. However, the lake acted like a nutrient sink, with more N, P, and TOC calculated in the inflows than the outflow. We found that it took 10–15 years of growth for actively rehabilitated pit lake catchments to approximate natural forest and 60 years for unrehabilitated pit lake catchments. Active rehabilitation that includes riparian-specific planting would likely lead to better outcomes for pit lake catchment vegetation. Connecting a pit lake to a river substantially increased catchment size and large amounts of river-derived carbon were deposited in the lake. However, carbon concentrations were relatively low compared to the size of the lake. Our results suggest that active intervention is required if stakeholders are unwilling to wait decades for the biological development of pit lakes

Minerals and trace elements in traditional foods of rural areas of Lhasa Prefecture, Tibet Autonomous Region (P.R. China)

Traditional foods play a major role in the diet of rural people living in the Tibet Autonomous Region of the People's Republic of China. Because these foods are mainly derived from local agriculture as well as artisanal production, their mineral composition may show significant discrepancies when compared with food composition data. This study aims at providing relevant data on the mineral composition of the main Tibetan foods. Sixteen different foodstuffs were sampled, including water, concentrated brewed black tea, chang, tsampa, wheat flour, dried cheese, dried yak meat, dried mutton, blood sausage, dried wild peaches, dried Chinese radish, and dried nettles. They were analyzed by inductively coupled plasma mass spectrometry (ICP-MS) for 19 minerals: Na, K, P, Ca, Mg, Fe, Zn, Mn, Cu, Ni, Se, Mo, Al, As, Cr, Co, Cd, Pb, and V. The validity of the results was ensured by the use of standard reference materials. A statistical comparison of the mean mineral contents of the analyzed foods against food composition data from the China Food Composition (CFC) table was carried out. It revealed significant discrepancies, emphasizing the importance of food analysis for nutritional assessment in Tibet autonomous region. To the best of our knowledge, the mineral compositions of some traditional Tibetan foods are here reported for the first time

INVESTIGATION OF SUSPECTED PERIPHERAL NEUROPATHY OUTBREAK IN DECHENTSEMO CENTRAL SCHOOL, THINLEYGANG, PUNAKHA

Background: A suspected peripheral neuropathy outbreak was reported from Dechentsemo Central School, Thinleygang, Punakha, following which the investigation team was immediately dispatched in the field. Objective: The aim of investigation was to ascertain the cause and risk factor for the outbreak in order to implement control measures. Methods: A case control study was devised for the investigation to study about the past exposure or deficiencies in order to find out the suspected cause and risk factors. A semi-quantitative food frequency questionnaire was administered to both cases and controls to collect information on the type of food they have consumed. The information garnered was analyzed using Chi-Square or Fischer Exact test for categorical variables and Man-Whitney U-test for quantitative variables. Results: All 17 cases were females with mean age of 13 years (SD 2.7 years). The average daily amount of thiamine intake was 0.6 mg/day for case and 0.8 mg/day for controls against the recommended daily allowance (RDA) of 1.2 mg/day. Case and control patients differed significantly with respect to fat intake (p-value = 0.02), more strongly with folate and iron intake (p-value < 0.01). Conclusion: The outbreak of peripheral neuropathy in Dechentsemo Central School appears to be linked to reduced dietary intake rich in vitamin B1 coupled with low intake of folate and iron in their diet

Minerals and Trace Elements Intakes and Food Consumption Patterns of Young Children Living in Rural Areas of Tibet Autonomous Region, P.R. China: A Cross-Sectional Survey

Background and objectives: Several studies revealed clinical signs of stunting and rickets among rural populations of Tibet Autonomous Region (T.A.R.), and especially amid children. Further, these populations are affected by a bone disease named Kashin-Beck disease (KBD). However, little is known about the dietary status of this population. This survey aimed to assess the usual intakes of young Tibetan children living in rural areas around Lhasa for energy, water, and ten minerals and trace elements (Na, K, Ca, P, Mg, Fe, Zn, Cu, Mn, and Se) involved in bone metabolism. Design: A cross-sectional survey was designed. Totally, 250 pre-school children aged 3–5 years living in rural areas were enrolled. The 24-h food recall method was used to collect the intakes for two days, during two different seasons (September 2012 and April 2013). Because Tibetan foods are mainly derived from local agriculture and artisanal production, a combination of food composition tables was compiled, including specific and local food composition data. Results: The Chinese dietary recommended intakes are not met for most of the elements investigated. Intake of sodium is much too high, while usual intakes are too low for K, Ca, Zn, Cu, and Se. Bioavailability of Ca, Fe, and Zn may be of concern due to the high phytic acid content in the diet. Conclusion: These nutrient imbalances may impact growth and bone metabolism of young Tibetan children. The advantages of the implementation of food diversification programs are discussed as well as the relevance of supplements distribution

La pertinence des données de composition des aliments pour les enquêtes nutritionnelles dans les régions rurales du Tibet: Étude pilote dans le cadre de la maladie de Kashin-Beck.

Kashin-Beck disease (KBD) is an endemic and chronic osteochondropathy. This disease principally occurs in the Tibet Autonomous Region and in several provinces of the People's Republic of China. The etiology of the disease remains obscure although environmental factors are assumed to be involved. Diet, in particular, differentiates the rural community, affected by KBD, from the other communities (nomads and city-dwellers), who remain unaffected. In anticipation of a nutrition survey, this study aimed to measure the mineral content (Ca, P, Mg, Fe, Zn, Mn, Cu, Ni, Se, Al, Sr, Mo, Cd, As, Pb, Hg, Cr, and Co) of eight Tibetan staple foods and to compare the results against two food composition tables (FCTs). Foods were sampled in twenty households selected from both an endemic and a non-endemic area of rural Tibet. Ten minerals involved in bone metabolism were measured using atomic and molecular spectrometric methods. Results revealed that a very limited number of food/constituent pairs showed a variation in mineral composition during a single year of testing for a given region. In addition, results showed significant differences in mineral content between the endemic and the non-endemic area, especially for wheat flour. Following our analysis of the mineral content of the Tibetan food samples, results were statistically compared with similar foods listed in two food composition tables: the USDA National Nutrient Database (USDA Food Search for Windows, Version 1.0, database version SR23), and the China Food Composition Table (book 1, 2nd edition). More than 50 to 60% of p-values < 0.05 were highlighted, suggesting the inappropriateness of using FCTs as a reference for nutrition surveys in rural Tibet, and emphasizing the need for analysis of traditional foods. Differences were found to be more or less marked depending on the element considered, and calcium content seemed to show the greatest difference. Although it is obviously too early for definite conclusions to be reached (insufficient number of samples by food and insufficient number of foods analyzed), it seems that the present pilot-study indicates significant discrepancies between measured and tabulated values of the mineral content of certain foods. A more complete survey would therefore seem mandatory.SCOPUS: ar.jinfo:eu-repo/semantics/publishe