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61.
Summary Topsoils (0–75 mm) from four soil types with different sulphate retention capacities were collected from stock camp and non-camp (main grazing area) sites of grazed pastures in New Zealand which had been annually fertilized with superphosphate for more than 15 years. These soils were analysed for different S fractions and incubated at 30°C for 10 weeks using an open incubation technique in order to assess the extent of S mineralization and the release of soluble soil organic S from camp and non-camp soils during incubation. The soils were preleached with 0.01 M KCl, followed by 0.04 M Ca(H2PO4)2 before being incubated. Pre-incubation leachates and weekly 0.01 M KCl leachates were analysed for mineralized S (i.e., hydriodic acid-reducible S) and total S. Soluble organic S was estimated as the difference between these two S fractions. Results obtained show higher cumulative amounts of all three S fractions in leachates over a 10-week incubation period in camp than in non-camp soils, suggesting that higher mineralization occurred in camp soils. Cumulative amounts of mineralized S from camp and non-camp soils showed a linear relationship with duration of incubation (R
20.985***), while the cumulative release of soluble organic S followed a quadratic relationship (R
20.975***). A significant proportion (14.6%–40.8%) of total S release in KCl leachates was soluble organic S, indcating that organic S should be taken into account when assessing S mineralization. Mineralized S and soluble organic S were best correlated with 0.01 M CaCl2-extractable soil inorganic S (R
2=0.767***) and 0.04 M Ca(H2PO4)2-extractable soil inorganic S(R
2=0.823***), respectively. Soil sulphate retention capacity was found to influence amounts of mineralized S and soluble organic S, and thus periodic leaching with KCl to remove mineralized S from soils may not adequately reflect the extent of soil S mineralization in high sulphate-retentive soils. In low (<10%) sulphateretentive soils, increasing the superphosphate applications from 188 to 376 kg ha–1 year–1 increased S mineralization but not amounts of C-bonded and hydriodic acid-reducible soil S fractions. 相似文献
62.
Hoang Thi Thanh Thuy Nguyen Nhu Ha Vy Tu Thi Cam Loan 《Water, air, and soil pollution》2007,182(1-4):73-81
The aquatic system of Hochiminh City comprises two main rivers: the Sai Gon and Nha Be rivers. Five canals discharge into these two rivers: NhieuLoc-ThiNghe, TauHu-BenNghe, TanHoa-LoGom, ThamLuong-BenCat and Doi-Te. The rivers and these canals collect effluent water from domestic and industrial sources. Most of these flows are not treated or at most are only primarily treated. A total of 33 sediment cores were taken from these rivers and canals. Chemical composition of these aquatic sediments has very high concentrations of several “urban” metals such as Cd, Cr, Cu and Zn. Most of the samples have exceeded the US EPA’s toxicity reference values for Cu, Zn and Cr (82, 82 and 70%, respectively). The highest concentrations of these metals appear to be associated with the uncontrolled and untreated industrial runoff to the discharge canals. These concentrations in fluvial sediment are relatively low, which indicates the dilution process of the contaminants. This finding indicates that the anthropogenic inputs play an important role in the elevation of heavy metals in the aquatic system and organic matter seems to exert a strong geochemical control on the amount of heavy metals. The Pearson correlation coefficients calculated for Cd, Cr, Cu and Zn, are 0.89; 0.72; 0.93 and 0.87, respectively. 相似文献
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67.
Hernot DC Biourge VC Martin LJ Dumon HJ Nguyen PG 《Journal of animal physiology and animal nutrition》2005,89(3-6):189-193
Fed the same diet, large and giant-breed dogs have higher faecal moisture and increased frequency of soft stools than small ones. This could be the result of physiological differences, such as a different gastrointestinal transit time. In this study, we have correlated mean total transit time (MTT) with body size and faecal consistency in dogs varying in body size. Fifty dogs from 13 different breeds were used, from a Dachshund to a Great Dane. The MTT was determined using coloured plastic beads [Cummings and Wiggins, Gut, Vol. 17 (1976), p. 219], and faecal consistency was scored daily during the study. We confirmed the strong correlation between height at the shoulder (body size) and faecal score (r = 0.76; p < 0.0001). The MTT increased with body size, from 22 h for a Miniature Poodle to 59 h for a Giant Schnauzer. We found significant positive correlations (p < 0.0001) between MTT and body size as well as faecal scores (r = 0.71 and 0.70 respectively). In the present study, we observed an effect of body size on MTT. In our 50 healthy dogs a longer MTT was related to a poorer faecal quality. Previous studies reported no relationship between body size and the upper gastrointestinal transit time in healthy dogs. So, we hypothesized that body size would mainly affect colonic transit time and that a longer colonic residence time would be related to a poorer faecal quality by promoting fermentation activity. 相似文献
68.
Vialard-Goudou A. Darrieussecq J. Lau Nguyen Thi 《Plant foods for human nutrition (Dordrecht, Netherlands)》1958,3(1):426-431
Résumé Les recherches sur la teneur en vitamines du groupe B (thiamine, riboflavine, nicotinamide) faites sur 135 végétaux alimentaires du Sud Vietnam, montrent que les plantes riches en thiamine sont rares; ce sont surtout les graines et quelques rares feuilles(Sesbania grandiflora
Pers. 0,365 mg% de partie comestible) et fruit (pulpe deTamarindus indica L. 0,374 mg %:Durio Zibethinus
Murr. 0,300 mg %).Les bonnes sources de riboflavine sont aussi rares mais ce sont essentiellement les légumes à feuilles vertes dont spécialementIpomoea aquatica
Forsk. 0,500 mg % et un champignonVolvaria esculenta
Massee 0,350 mg %.Enfin la nicotinamide se trouve en quantité importante dans les plantes alimentaires étudiées et sa répartition est assez variée. Les teneurs les plus élevées se trouvent dans les graines comme:Arachis hypogea L. 12 mg %,Citrullus vulgaris
Schrad. 8,450 mg %Sesamum indicum L. 5,970 mg %.
Summary The vitamins of the B group (thiamine, riboflavine, nicotin amide) were analysed in 135 edible plants from South-Vietnam. The plants rich in thiamine are rare; some seeds, rarer leaves(Sesbania grandiflora Pers. 0.365 mg % of the edible part) and fruits (pulp ofTamarus Indica L. 0.374 mg %,Durio Zibethinus Murr 0.3 mg %) were found.The rich sources of riboflavine are equally rare; into the group belong especially green leaves, in particularIpomoea aquatica Forsk, 0.5 mg % and a fungus,Volvaria esculenta Massee 0.35 mg %.Nicotinamide is found in greater quantities in the analysed plants, the allotment being rather great. The greatest amounts have been found in the seeds:Arachis hypogea L. 12 mg %,Citrullus vulgaris Schrad 8.45 mg %Sesamum Indicum L. 5.97 mg %.
Zusammenfassung Die Vitamine der B-Gruppe (Thiamin, Riboflavin, Nicotinsäureamid) wurden in 135 essbaren Pflanzen aus Süd-Vietnam bestimmt. Thiamin-reiche Pflanzen sind selten: manche Samen, seltener manche Blätter,(Sesbania grandiflora Pers. 0,365 mg % des essbaren Teiles) und Früchte (Fleisch vonTamarindus indica L. 0,374 mg %,Durio Zibethinus Murr 0,3 mg %).Gute Quellen an Riboflavin sind ebenso selten. Solche sind besonders grüne Blätter, namentlich vonIpomoea aquatica Forsk, 0,5 mg %, und ein Pilz,Volvaria esculenta Massee 0,35 mg %.Nicotinsäureamid findet sich in wechselnden Mengen in den untersuchten Pflanzen. Die höchsten Gehalte sind in Samen zu finden:Arachis hypogea L. 12 mg %,Citrullus vulgaris Schrad. 8,45 mg %,Sesamum indicum L. 5,97 mg %.相似文献
69.
We investigated whether the addition of either spinach or sweet-potato leaves to the diet of growing pigs, kept in small holdings in Central Vietnam, would improve growth performance. A control diet was formulated and mixed with each of the vegetables to a final concentration of 15% of the total dietary dry matter. The diets were fed to the pigs from 70 to 100 days of age on six different smallholder farms in Central Vietnam. There were three animals per treatment group per farm and biopsies of adipose tissue were analysed for their contents of alpha-linolenic, eicosapentaenoic and docosahexaenoic acids. The diets without and with vegetables contained on average 0.14 and 0.32 g alpha-linolenic acid per MJ metabolizable energy. The relative percentage of alpha-linolenic acid in adipose tissue was raised by the intake of the vegetables. Eicosapentaenoic acid was not detectable in adipose tissue and the level of docosahexaenoic acid was unchanged. There was a significant stimulatory impact of the intake of either spinach or sweet-potato leaves on growth performance of the growing pigs. It is suggested that an adipose tissue content of alpha-linolenic acid less than 1% of total fatty acids does not allow maximum growth in growing pigs. 相似文献
70.
Prevalence of Salmonella spp. in pigs, chickens and ducks in the Mekong Delta, Vietnam 总被引:1,自引:0,他引:1
Tran TP Ly TL Nguyen TT Akiba M Ogasawara N Shinoda D Okatani TA Hayashidani H 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2004,66(8):1011-1014
In order to determine the prevalence of Salmonella spp. in domestic animals in 6 provinces of the Mekong Delta, Vietnam, 1,098 fecal or intestinal content samples from pigs, chickens, and ducks were examined in the period from July to October, 2000. Salmonella spp. were isolated from 78 (7.1%) of the total samples, which included 23 (5.2%) of 439 pigs, 24 (7.9%) of 302 chickens, and 31 (8.7%) of 357 ducks. From those samples, 80 Salmonella strains were isolated and 25 serovars were identified. The predominant serovars were S. Javiana, S. Derby, and S. Weltevreden. S. Javiana and S. Weltevreden were detected together in pigs, chickens, and ducks. These results indicate that the serovars of Salmonella are widely distributed in domestic animals in the Mekong Delta, Vietnam. 相似文献