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421.
422.
Sigua Gilbert C. Holtkamp Mike L. Linton John M. Coleman Samuel W. 《Journal of Soils and Sediments》2003,3(2):93-99
Background The continued need to dredge lakes, rivers, and canals in Florida, both for maintenance and environmental improvement, will
produce millions of cubic meters of dredged materials. Productive disposal options of lake-dredged materials (LDM) may provide
substantial and intangible benefits that will enhance the environment, community, and society.
Objective The objective of this study was to assess lake-dredged materials from Lake Panasoffkee as soil amendment for early establishment
of bahiagrass (BG,Paspalum notatum Flügge) in subtropical beef cattle pasture at Sumter County, Florida. Results and Discussion. This study encompassed two
phases: Phase 1 comprised of five small observation plots (0.3 x 0.3 m); Phase 2 consisted of five larger test plots (30.5
x 30.5 m). Each of the plots in Phase 1 and Phase 2 had a different ratio LDM to natural soil (NS): Plot 1 (0% LDM + 100%
NS); Plot 2 (25% LDM + 75% NS); Plot 3 (50% LDM + 50% NS); Plot 4 (75% LDM + 25% NS); and Plot 5 (100% LDM + 0% NS). Each
plot was seeded with BG and early growth and yield establishment were monitored for 16 weeks.
Conclusion Results disclosed significantly taller (p ≤ 0.001) plants and higher biomass production (p ≤ 0.001) of BG from plots amended
with 75% LDM than those of BG planted on plots with 0% LDM. Results suggest that LDM can serve as source of lime and fertilizer
to establish BG beef pasture fields. Sediments with high CaCO3 improved the physical and chemical conditions of subtropical beef pastures. Lake-dredged materials could be removed from
the spoil containment areas, trucked to other locations, and incorporated into existing fields for agricultural uses. There
is still much to be learned, but it is certain that Lake Panasoffkee sediments should be regarded as a resource, with no observed
harmful ecological effects.
Recommendation and Outlook The agricultural or livestock industry could utilize these LDM to produce forages. LDM should be regarded as a beneficial
resource, as a part of the ecological system. This study has been continued for several years to explore and assess the long
term efficacy of LDM on productivity and quality of BG beyond its early establishment stage.
Joint contribution of the USDA-ARS and the Florida Agricultural Experiment Station, Journal Series No, R-09253. 相似文献
423.
Chris?M.?TheobaldEmail author Mike?Talbot Fabian?Nabugoomu 《Journal of Agricultural, Biological & Environmental Statistics》2002,7(3):403-419
The inclusion of covariates in models for analyzing variety × environmental data sets allows the estimation of variety yields for specific locations within a region as well as for the region as a whole. Here we explore a Bayesian approach to the estimation of such effects and to the choice of variety using a possibly incomplete variety × location × year data set that includes location × year covariates. This approach allows expert knowledge of the crop and uncertainty about local circumstances to be incorporated in the analysis. It is implemented using Markov chain Monte Carlo simulation. An example is used to illustrate the approach and investigate its robustness. 相似文献
424.
International experience of Policy Councils on food and nutrition has developed over recent decades but they have not received the attention that is due to them. The 1992 International Conference on Nutrition recommended that governments create Food Policy Councils but few have been created. There has been more experience in local and sub-national policy councils, particularly in North America. Developing country experience of attempting to improve food policy integration stems from the 1970s. The UK's House of Commons' (Parliamentary) Health Committee, in its 2004 report on obesity, reviewed current policy determinants of the rise in obesity, concluding that national food and health policy lacked coherence, integration and effectiveness. To address this vacuum, it proposed the creation of a new 'Council of Nutrition and Physical Activity to improve co-ordination and inject independent thinking into strategy'. The case for creating such a Council in the UK is reviewed, as are possible organisational options, functions and remit. A Council could be created under the forthcoming Public Health Act. The purpose of the new Council would be to provide independent advice and strategic advice as well as monitor the linkages between policies on food, nutrition and physical activity, noting their environmental implications. 相似文献
425.
An experiment was conducted to test the hypothesis that the requirement for Ca expressed as a ratio between standardized total tract digestible (STTD) Ca and STTD P obtained in short-term experiments may be applied to pigs fed diets without or with microbial phytase from 11 to 130 kg. In a 5-phase program, 160 pigs (body weight: 11.2 ± 1.8 kg) were randomly allotted to 32 pens and 4 corn–soybean meal-based diets in a 2 × 2 factorial design with 2 diet formulation principles (total Ca or STTD Ca), and 2 phytase inclusion levels (0 or 500 units/kg of feed) assuming phytase released 0.11% STTD P and 0.16% total Ca. The STTD Ca:STTD P ratios were 1.40:1, 1.35:1, 1.25:1, 1.18:1, and 1.10:1 for phases 1 to 5, and STTD P was at the requirement. Weights of pigs and feed left in feeders were recorded at the end of each phase. At the conclusion of phase 1 (day 24), 1 pig per pen was euthanized and a blood sample and the right femur were collected. At the end of phases 2 to 5, a blood sample was collected from the same pig in each pen. At the conclusion of the experiment (day 126), the right femur of 1 pig per pen was collected and carcass characteristics from this pig were measured. No interactions were observed between diet formulation principle and phytase inclusion for growth performance in any phase and no differences among treatments were observed for overall growth performance. Plasma Ca and P and bone ash at the end of phase 1 were also not influenced by dietary treatments. However, on day 126, pigs fed nonphytase diets formulated based on total Ca had greater bone ash than pigs fed STTD Ca-based diets, but if phytase was used, no differences were observed between the 2 formulation principles (interaction P < 0.05). At the end of phases 2 and 3, pigs fed diets without phytase had greater (P < 0.05) plasma P than pigs fed diets with phytase, but no differences were observed at the end of phases 4 and 5. A negative quadratic effect (P < 0.05) of phase (2 to 5) on the concentration of plasma Ca was observed, whereas plasma P increased (quadratic; P < 0.05) from phases 2 to 5. However, there was no interaction or effect of diet formulation principle or phytase inclusion on any carcass characteristics measured. In conclusion, STTD Ca to STTD P ratios can be used in diet formulation for growing-finishing pigs without affecting growth performance or carcass characteristics and phytase inclusion ameliorates bone resorption caused by low dietary Ca and P. 相似文献
426.
Caroline A. Sullivan David Bourke Micheline Sheehy Skeffington John A. Finn Stuart Green Stephen Kelly Mike J. Gormally 《Biological conservation》2011,(3):1089-1099
A significant policy objective is the need for protection of biodiversity not just within designated Natura 2000 sites, but also in areas that occur outside of these sites. However there is a lack of information on existing semi-natural habitat cover on EU farms, making it difficult to assess whether targets for halting the loss of agricultural biodiversity are being met. To achieve these targets, reliable yet easy-to-use methods are needed for accurately identifying priority areas for conservation actions and monitoring biodiversity on a large spatial scale.Remote sensing, farmland statistics and species data have been used in some EU countries to create maps to estimate the extent of semi-natural habitat cover but these are acknowledged as being too broad scale. In this study, we examined a method of fine-scale prediction of the spatial coverage of semi-natural habitats in lowland farms. A generalized additive model (GAM) was used to investigate the relationships between landscape and farm management variables and the lowland farmland habitat biodiversity on 32 farms outside of conservation designations, in a region of western Ireland. Semi-natural habitat cover on lowland farms could be predicted with a model using stocking density, soil diversity and river and stream length. It is proposed that this model could be used to predict the coverage of semi-natural habitats on farms in other regions of Ireland with similar land-use and landscape. A similar modelling approach could be adapted for application in other regions of Ireland and across Europe with different landscapes to predict semi-natural habitat coverage. 相似文献
427.
Smith MR Penner MH Bennett SE Bakalinsky AT 《Journal of agricultural and food chemistry》2011,59(13):6871-6876
A standard method for assaying protein in red wine is currently lacking. The method described here is based on protein precipitation followed by dye binding quantification. Improvements over existing approaches include minimal sample processing prior to protein precipitation with cold trichloroacetic acid/acetone and quantification based on absorbance relative to a commercially available standard representative of proteins likely to be found in wine, the yeast mannoprotein invertase. The precipitation method shortened preparation time relative to currently published methods and the mannoprotein standard yielded values comparable to those obtained by micro-Kjeldahl analysis. The assay was used to measure protein in 48 Pinot noir wines from 6 to 32 years old. The protein content of these wines was found to range from 50 to 102 mg/L with a mean value of 70 mg/L. The availability of a simple and relatively rapid procedure for assaying protein provides a practical tool to quantify a wine component that has been overlooked in routine analyses of red wines. 相似文献
428.
429.
Whelen JC Houston DM White C Favrin MG 《The Canadian veterinary journal. La revue veterinaire canadienne》2011,52(12):1353-1355
This report describes light and scanning electron microscopic appearance of an ovum from the giant kidney worm, Dioctophyme renale found in the nidus and stone layer of a struvite calculus. The stone had been surgically removed from the bladder of a 4-year-old spayed female mixed breed dog from northern Ontario. 相似文献
430.
Shannon E. Pratt-Phillips Sue Stuska Heather L. Beveridge Mike Yoder 《Journal of Equine Veterinary Science》2011,31(11):640-644
This preliminary study describes the nutritional profiles of the horses of Shackleford Banks, NC. Nutrient composition of plants was analyzed during the four seasons over 2 years. Microhistological examination of the feces was used to determine the contribution of the various plant types to the horse’s diet. Together, this information provided an estimate of the nutrient profile for these horses. There were significant differences in nutrient content between the main plant types analyzed, as well as differences between the seasons for several nutrients (such as crude protein [CP] and acid detergent fiber [ADF]). Grasses were the primary plant type found in the feces of the horses, although forbs were also found, particularly in the winter and spring. It is likely that plant availability and palatability affect selection because plant nutrient content did not have a significant relationship with consumption. The yearly diet had an average of 6.6% ± 1.4% CP, 0.5% ± 0.1% calcium, 0.1% ± 0.03% phosphorus, 8.3 ± 2.25 ppm copper, 23.2 ± 4.70 ppm zinc, and 1.9 ± 0.07 Mcal/kg digestive energy (DE). Thus, even at an intake of 3% of body weight, these horses are likely deficient in phosphorus, zinc, and copper several times throughout the year. Future studies should include expanded plant sampling, habitat information, additional fecal samples, and body condition scores of the horses. 相似文献