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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 …


Variation In C/P Ratios In Devonian-Mississippian Marine Shales: Testing The Productivity-Anoxia Feedback Model, Brian T. Scott Jan 2009

Variation In C/P Ratios In Devonian-Mississippian Marine Shales: Testing The Productivity-Anoxia Feedback Model, Brian T. Scott

University of Kentucky Master's Theses

Carbon/phosphorus ratios for late Devonian-early Mississippian marine black shales along a transect from the Illinois Basin, across the Cumberland Saddle, and into the Appalachian Basin were evaluated to assess the role of productivity in organic carbon accumulation. Phosphorus is a key limiting nutrient for biological productivity in marine environments and may be regenerated preferentially relative to organic carbon, the amount of regeneration possibly being related to bottom-water anoxia. A positive feed-back mechanism (more specifically, productivity-anoxia feedback or PAF) has been proposed between water-column anoxia, high benthic regeneration of phosphorus, and marine productivity. This regeneration of phosphorus under anoxic conditions and …


Effects Of Soil Erosion On Productivity, Wilbur Frye Jul 1980

Effects Of Soil Erosion On Productivity, Wilbur Frye

Soil Science News and Views

About 75 percent of Kentucky's agricultural land is sloping enough that potential erosion losses must be considered in its management. In addition to the effect of soil erosion on water pollution is the question of its effect on the productivity of the soil. This is a complex question due to the interactions of the many factors that affect crop growth. Furthermore, the same degree of erosion has a greater adverse effect on some soils than on others. The kind of erosion that has taken place or is taking place is a major factor in making land use decisions for crop …


Biological And Chemical Evaluation Of The Aquatic Environment Of Selected Undeveloped Kentucky Lake Embayments, Marshall Gordon, Morgan E. Sisk Dec 1976

Biological And Chemical Evaluation Of The Aquatic Environment Of Selected Undeveloped Kentucky Lake Embayments, Marshall Gordon, Morgan E. Sisk

KWRRI Research Reports

This report describes research involving biological and chemical analysis of two undeveloped embayments on Kentucky Lake, namely Anderson and Vickers Bays. Field and laboratory studies were made to assess current biotic standing crops, limnological conditions, levels of inorganic and organic pollutants in the embayments.