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Full-Text Articles in Physical Sciences and Mathematics

Forage Allowance And Cow Genotype, Tools To Increase Animal Production In Native Pastures, Pablo Soca, Mariana Carriquiry, Martín Do Carmo Dec 2019

Forage Allowance And Cow Genotype, Tools To Increase Animal Production In Native Pastures, Pablo Soca, Mariana Carriquiry, Martín Do Carmo

IGC Proceedings (1997-2023)

In eight plots (four per block) the effects of two FA per two cow genotypes were tested from August 2007 to March 2010, on a Campos grassland (major species were Axonopus affinis, Oxalis sp., Cyperus sp., Cynodon dactylon, Eryngium nudicaule, Gaudinia fragilis, Chevreulia sarmentosa, Stipa setigera, Paspalum notatum and Coelorhachis selloana) in Uruguay (32º 20` S, 54º 26` W). Forage allowance varied seasonally, in HIGH (5, 3, 4 and 4 kg DM/kg LW) and LOW (3, 3, 2 and 2 kg DM/kg LW) during autumn, winter, spring and summer; respectively. Continuous stocking method was …


Legumes, Livestock And Livelihoods In The Australian Mixed Farming System, E. C. Wolfe Nov 2019

Legumes, Livestock And Livelihoods In The Australian Mixed Farming System, E. C. Wolfe

IGC Proceedings (1997-2023)

This Howard Oration describes the pathway that I have taken towards my specialisation in ‘big picture’ agriculture. A simple protocol is presented for the analysis of agricultural systems by using descriptive or quantitative indicators of five system properties: productivity, sustainability, profitability, social wellbeing and political acceptability. These properties are further illustrated by considering four important issues in the Australian sheep-wheat belt, a distinctive world food production system. The issues are the supply of and demand for legume nitrogen for crops, reconciling agricultural and natural resource objectives, the low profitability of farms in relation to production and marketing risks, and the …


Effects Of Pressure Drop Funnels Model Of Different Shapes On Cbm Well Productivity, Hu Haiyang, Jin Jun, Zhao Lingyun, Chen Jie, Gu Jiaoyang Jun 2019

Effects Of Pressure Drop Funnels Model Of Different Shapes On Cbm Well Productivity, Hu Haiyang, Jin Jun, Zhao Lingyun, Chen Jie, Gu Jiaoyang

Coal Geology & Exploration

In order to study the effect of pressure drop funnel shapes on CBM well productivity, the change law of pressure and the shape of pressure drop funnel in different drainage stages of CBM wells were discussed, the mathematical models of pressure drop funnel were established, the concept of "desorption coefficient" and "effective desorption coefficient" for coal reservoir were proposed to quantitative study desorption effect of the coal reservoir. Taking a CBM well in the west of Guizhou as an example, the research results show that the logarithmic function model of pressure distribution of radial flow is difficult to accurately reflect …


Iron Fertilization With Enhanced Phytoplankton Productivity Under Minimal Sulfur Compounds And Grazing Control Analysis In Hnlc Region, Tai-Jin Kim, G. H. Hong, D. G. Kim Kim, Mark Baskaran Jan 2019

Iron Fertilization With Enhanced Phytoplankton Productivity Under Minimal Sulfur Compounds And Grazing Control Analysis In Hnlc Region, Tai-Jin Kim, G. H. Hong, D. G. Kim Kim, Mark Baskaran

Environmental Science and Geology Faculty Research Publications

The present study investigated quantitatively the significance of HNLC (high-nutrient low-chlorophyll) regions and its grazing control with the im- proved iron fertilization for climate change. The limitation of iron (Fe) for phytoplankton growth in HNLC regions was confirmed by sulfur compounds (S) such as volcanic ash and hydrogen sulfide (H2S) in batch cultures, whose chemical sediment of Fe3S4 showed 4.06 wt%. The technologies developed for iron fertilization since 1993 till now were not practical to provide sufficient amounts of bioavailable iron due to sedimentary iron sulfides induced by undersea volcanic sulfur compounds. The proposed technology for iron fertilization was improved …


Method And Application Of Diagnosis Of Low Productivity Damage Of Cbm Wells, Feng Qing Jan 2019

Method And Application Of Diagnosis Of Low Productivity Damage Of Cbm Wells, Feng Qing

Coal Geology & Exploration

Coal reservoirs differ from conventional reservoirs, are easily damaged and the damage factors are complex. Massive papers focus on CBM damage mechanism, but fewer studies on pollution types and stimulating measures. This paper studied various factors influencing CBM and water production in a block of Qinshui basin from angle of geology, engineering and drainage, and established the typical production curve model to determine reservoir judgement method of damage types of low production wells, layer and well selection standards for reservoir with big yield-increasing potential to carry out second reconstruction. The results proved that factors influencing CBM wells productivity such as …