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Governors Slightly More Bound? A Critique of the Uniform Law Commission\u27s Model Public-Health Emergency Authority Act
No full textANALYSIS OF DYNAMIC AND FINAL SURFACE SUBSIDENCE MOVEMENTS OVER SUBCRITICAL PANELS IN THE EASTERN US
No full textSubsidence prediction is a critical field in mining engineering, focusing on anticipating ground movements caused by underground coal extraction. Accurately forecasting these movements is essential for protecting surface structures and infrastructure from damage. However, despite extensive research by mining professionals worldwide, reliable prediction remains challenging, especially in complex environments like subcritical mining areas and locations characterized by highly variable topography. These conditions introduce non-linear rock mechanics that often complicate the application of traditional predictive models. This thesis utilizes measured subsidence data related to the extraction of two adjacent longwall panels in a deep coal mine in the eastern US to develop site-specific best-fit models for subsidence prediction. The Surface Deformation Prediction System (SDPS) software package was used, which employs the influence function method. Analyses were conducted both for final and dynamic conditions. Prediction and measurement values are compared using the root mean square error and the relative root mean square error. The development of site-specific models was impacted by measured upsidence values due to the valley effect. In addition, subsidence movements over an already mined panel continue during mining of the neighboring panel due to the highly subcritical nature of the operation
Persistence of Roundleaf Cassia in Grazed Pastures - A Conceptual Model
Full text linkRoundleaf cassia (Cassia rotudifolla) cv. Wynn is a short-lived perennial that relies on seedling recruitment for long-term persistence. Its persistence is considered in terms of survival of plants from the initial sowing, seed set, seedling recruitment, run-down of reserves of soil seed, and survival of seedlings. The major factor controlling all these stages is soil moisture stress; grazing management \u27is less important. A conceptual model of Wynn persistence is presented and progress in mathematical modeiling is reported.
Grassland Opportunities in the Subtropical Region of South America
Full text linkNatural grasslands represent a significant proportion of southern South America, which, despite the increase in cropland, is being maintained. However, ignorance and misinformation about the potential of the natural grassland and its environment lead to poor economic results, with live-weight gains (LWG) of around 50-60 kg/ ha/year. Work on the soil-plant-animal relationship have shown that animal performance can be raised to 150-160 kg LWG/ha/year, using sound management practices. The improvement of natural grassland through lime, fertilisation and introduction of exotic species (sodseeding) can further increase production to 500-600 kg LWG/ha/ year. These results illustrate the great potential of natural grasslands in southern South America. The potential of the environment can be exploited more by incorporating new forage plants into the croplands, so increasing production to 1000-1500 kg LWG/ha/year. Development and adoption of this technology will benefit society but require greater investment in research than at present and the research which is conducted must emphasise environmental and economic aspects of production
Improving Hill Agriculture Systems in Nepal: A Case Study
Full text linkThe Kingdom of Nepal is characterised by complex, diverse smallholder farming systems in which crops, livestock and forest resources are all interlinked. Traditional feeding practices throughout the hills are coming under severe pressure due to the high density of livestock. Consequently, acute shortages of forage are e, experienced, especially during the dry winter season. A case study is presented In which the integration of forage management into the whole farming system is practised, User groups are improving community grazing lands by the introduction of more productive herbage and fodder tree species. Fodder is sold to livestock farmers, animal management is intensified and the increased supply of manure is used to fertilise high value crops. Constraints upon the development of fodder programmes are discussed. It is concluded that the case study discussed is a good example of how applied agricultural research and extension can achieve a practical response to a changing situation
Comparative Use of Digitaria decumbens and Cynodon nlemfuensis by Local Suckling Ewes in Martinque (FWI)
Full text linkPastures of Digitaria decumbens (Dd) and Cynodon nlemfuensis (Cn) were each grazed by 64 native suckling ewes ( 40 ewes/ha) in Martinique. Forage characteristics, ewe feeding behaviour and lamb growth were studied. The available herbage mass (kg DMJLW0-75/day) was lower for the Dd pastures than for the Cn pastures: 295 v. 355 for the leaves (P\u3c0.05) and 820 v, 1360 for the stems (P\u3c0.01), respectively. There was no difference in the diurnal activities (grazing, ruminating) between the ewes in the 2 groups. Number of bites/min was higher on Dd pasture than that for Cn: 31 v. 26 (P\u3c0.001), Preweaning daily weight gain (g/day) was higher for the Dd lambs group than for Cn: 170 v. 140 (P\u3c0.01). The lamb mortality rate(%) was respectively: 15 v. 27 (P\u3c0.05). Pasture management problems are discussed
Fattening Heifers on Nitrogen Fertilized and Irrigated Pastures: A Productive and Sustainable System for the Tropics?
Full text linkBeef production from nitrogen-fertilised and irrigated pastures was studied for 4,S years on vertisols, South Martinique (rainfall 1400 mm). Digitaria decumbens (pangola) pastures received 230��7S-ISO kg/ha/year N-P·K and were rotationally grazed (S days grazed, 30 days rested) all year round with a fixed stocking rate (6.6 heifers/ha). Mean live-weight gains were: 1121 kg/ha/year and 170 kg/head/ year. Pangola showed good persistence and cover at the end of the experiment exceeded 9S%, It is concluded that heifers fattening on nitrogen-fertilised pastures is a productive and stable system
Milk Yield of Cows with Different Genetic Potential on Grass and Grass-Legume Tropical Pastures
Full text linkA grazing experiment was carried out at CIAT\u27s Quilichao research station to assess the effect of legumes selected for acid soils on milk production of cows with different genetic potential. Pastures of Brahiaria dictyoneura cv. Llanero and Andropogen gayanus cv. Carimagua l, alone and in association with Centrosema acutifolium (CIAT 5568) and C. macrocarpum (CJAT 5713), were grazed by Holstein and Zebu crossbred cows using a Latin square crossover design. Fat corrected milk (FCM) yield of Holstein cows was 17 and 19% higher in the associations of B. dictyoneura and A. gayanus, respectively, than in the grass-only pastures. With the Zebu crosses PCM yield was 13% higher in the B. dictyoneura ra-legume pastures, but no response was observed in the A. gaya,ms-legume pastures. Milk composition was not affected by pasture treatment. Results suggest that grass-legume pastures selected for acid soils can significantly increase milk production, particularly when cows have medium genetic potential
Agronomic Evaluation of Centrosema Germplasm on Acid Utisol in the Humid Tropics of Peru. II. Centrosema tetragonolobum Schultze-Kraft & Williams
Full text linkThe agronomic potential of 11 accessions of Centrosema tetragonolobum was assessed In a small-plot clipping trial conducted near Pucallpa, Peru. These accessions were compared with 8 selected accessions of C. acutifolium, C, brasilianum and C. macrocarpum, and 3 accessions of the agronomically little-known C. brachypodum and C. capitatum. All C. tetragonolobum accessions were well adapted to an acid ultisol (pH 4.S, 80% Al saturation). Several of them produced dry matter and seed yields similar to those of promising lines of C. acutifolium and C. macrocarpum, The capacity to root at trailing stems was poor for C. tetragonolobum, C. brasillanum and C. brachypodum, but good for the other species. C. tetragonolobum accessions, with a few exceptions, were more tolerant of rhizoctonia foliar blight than the closely related C. brasilianum. Agronomic performance of accessions of C. bracl1ypodum and C. capltatum was moderate to poor