Digital Commons Network^™

Productivity And Composition Of Two Improved Native Pastures Under Different Grazing Managements In Uruguay, D. F. Risso, E. J. Berretta, G. Carracelas

IGC Proceedings (1977-2023)

Two improved native pastures were established by phosphoric (P) fertilisation and oversowing of: white clover (Trifolium repens) mixed with birdsfoot trefoil (Lotus corniculatus) (TbL) and annual lotus (Lotus subbiflorus) (Rin). Such pastures were evaluated during 5 years with steers at two stocking rates (High and Low) and two grazing managements (Rotational and Alternate). Presence of legumes was high and botanical changes were favourable in both pastures that evidenced good persistence. Daily liveweight gains of steers and total animal production were high in both pastures, but significantly (P≤ 0.05) higher in TbL. No significant differences …

Back To The Roots - Do Traditional Maasai Management Strategies Work Towards Resilience Against Unpredictable Rainfall And Grazing Pressure In Northern Tanzania?, S. A. Baumgartner, A. C. Treydte

IGC Proceedings (1977-2023)

Despite the importance for people´s livelihoods, many semi-arid African savannas are prone to heavy degradation due to overutilization by people, livestock and increased climate variability. Rangeland management, such as transhumance and deferred grazing systems, practiced by the Maasai in northern Tanzania, can be useful in combating the negative consequences of overuse and increasing rainfall variability. But little is known on how different rangeland regimes, practiced by the Maasai, impacts the productivity of these rangelands.

We collected data on regrowth rates under different rangeland management regimes (rainy season grazing land, dry season grazing land, and seasonal exclosures), different harvest rates (month, …

Digestibility Estimates Based On A Grass Growth Model Are Distributed Via Internet To Finnish Farmers, Marketta Rinne, J. Nousiainen, I. Mattila, H. Nikander, P. Huhtanen

IGC Proceedings (1977-2023)

Optimising the harvesting time of grass in primary growth is difficult under Finnish climatic conditions, because the digestibility of grass decreases on average by 0.5 percentage units daily. We constructed a model based on cumulative temperature and geographical location which estimates the digestibility of grass. This model is used to produce estimates utilising real time weather information. The estimates are presented as a map, which is revised daily. Farmers have free access to the maps via Internet.

Reducing Tillage Affects Long-Term Yields But Not Grain Quality Of Maize, Soybeans, Oats, And Wheat Produced In Three Contrasting Farming Systems, Kirsten Ann Pearsons, Emmanuel Chiwo Omondi, Brad J. Heins, Gladis Zinati, Andrew Smith, Yichao Rui

Agricultural and Environmental Sciences Faculty Research

Reducing tillage has been widely promoted to reduce soil erosion, maintain soil health, and sustain long-term food production. The effects of reducing tillage on crop nutritional quality in organic and conventional systems, however, has not been widely explored. One possible driver of crop nutritional quality might be the changing soil nitrogen (N) availability associated with reduced tillage in various management systems. To test how reducing tillage affects crop nutritional quality under contrasting conventional and organic farming systems with varied N inputs, we measured nutritional quality (protein, fat, starch, ash, net energy, total digestible nutrients, and concentrations of Ca, K, Mg, …

Remote Sensing Application To Grassland Monitoring, Z. B. Nan

IGC Proceedings (1977-2023)

Application of remote sensing to the management of grassland resources, the role this plays in developing sustainable grassland farming systems and opportunities for further development are outlined. Use of remote sensing technologies in grassland monitoring has a history of more than 30 years. Both fine- and coarse-grained remote sensing techniques are used to monitor and study grasslands. Fine-grained techniques are used to study landscape scale processes through the use of sensors providing spatial resolution of a few meters, whereas coarse-grained techniques are used to study catchment scale areas, and even entire biomes, using satellite-based sensors with a spatial resolution of …

Modelling Grassland Ecosystems, J. H. M. Thornley

IGC Proceedings (1977-2023)

In this contribution a view of the promise and difficulties of modelling grassland is given. This is largely centred around work with a grassland ecosystem simulator known as the Hurley Pasture Model.

A brief introduction sets forth possible reasons for building a large ecosystem model, and stresses the importance of modelling objectives. It is suggested that a model is de rigeur for any research programme which aims to take a firm grasp of the complex responses of grassland. Mechanistic models are required to provide the understanding needed for intelligent and flexible management of grassland, whatever the prevailing environmental or economic …

Grassland Management And Animal Product Quality, G. W. Sheath, J. B. Coulon, Q. A. Young

IGC Proceedings (1977-2023)

The expectations of consumers ultimately determine the specification of product quality; and grassland systems produce a wide range of animal-based products. Therefore, to provide focus, this paper deals only with food products that are destined for markets that exhibit strong discretionary choice. Quality expectations of consumers have traditionally been based on product attributes such as taste, freshness, nutritional value and appearance, but customer expectations are expanding to encompass food safety, environmental care, animal welfare and biotechnologies.

Grassland forages and their management influence the intrinsic sensory properties of food. A dairy products case study is presented, indicating that pasture species and …

Priority Setting And Funding Of Agricultural Research, M. Petit

IGC Proceedings (1977-2023)

Agricultural research funding amounts and modalities have been profoundly transformed in recent years in many countries. For instance, competitive funding has become the norm rather than the exception in most countries and funding sources have been greatly diversified. In addition, in some major countries, the private sector has become a major actor In agricultural research, both as a funder of research and as a provider research results. This poses a major challenge to public research institutions, which remain the major agricultural research actors and employers of researchers in most countries. With these changes in funding, formal procedures for research priority-setting …

Contextual Factors In The Management Of Common Grazing Lands: Lessons From Mongolia And Northwestern China, R. Mearns

IGC Proceedings (1977-2023)

Seen in a global perspective, pastoral development is now increasingly motivated by social and environmental objectives rather than by production- or output-orientated objectives. Attention is shifting towards a broader concern with sustainability, both of grasslands, and of the livelihoods of those who rely on them (de Haan et al, 1997, Fratkin and Mearns forthcoming). Quite how these twin sustainability objectives may be achieved in particular contexts, however, is an empirical question. Drawing on examples from a diverse range of natural grassland-based livestock production systems under economic transition in Mongolia and northwestern China, this summary paper aims to show how an …

De-Intensification Of Grasslands: Understanding The Processes To Find The Balance, K. C. Hodgkinson

IGC Proceedings (1977-2023)

There is a growing trend in Australia and other developed countries for deintensification of animal production from grasslands and for grasslands to be used for purposes other than livestock grazing. These shifts are occurring for a variety of reasons including unsustainable land management practices, environmental pollution, loss of conservation value, poor commodity prices and declining rural infra-structure and communities. In Australia, the shifts are under way in agricultural grasslands, where sown pastures occur in a matrix of semi-natural woodlands, but less so in the other three major natural grasslands that forms the arid and semi-arid rangelands.

The conversion of natural …

De-Intensification Of Grasslands: Current State And Trends, Michael Duru, Bernard Hubert

IGC Proceedings (1977-2023)

De-intensified use of grasslands, and more generally of the livestock systems they support, has been triggered by a growing sensitivity of citizens to environmental quality (nitrogen) and quality of animal products, and by the warnings addressed to political authorities by scientists about the environmental consequences of economic imbalances (decreasing biodiversity, drop in soil fertility, greenhouse effect), and in particular of food overproduction in Europe.

From an ecological standpoint, grassland de-intensification must be envisaged whenever the techniques implemented disrupt resource sustainability. The grassland resource itself may be at risk when a rate of vegetation offtake by herbivores that is incompatible with …

Soil Resilience And Arbuscular Mycorrhizal Fungi: How Fungi Can Inform Climate Change Mitigation And Adaptation In Maya Milpa Management, Courtney Mathers

Electronic Theses and Dissertations

In Mexico’s state of Yucatán, climate change impacts like prolonged and less predictable dry season length are manifesting as threats to agricultural production and food security. Nearly two thirds of Yucatán’s population is indigenous, many of whom live in rural communities that rely on rainfed subsistence agriculture (INEGI 2015). Ensuring sufficient food production in the face of climate change relies on the quality of agricultural soils. With both mismanagement of agricultural soils and climate change posing as threats to food production in Mexico, soil management practices that increase a soil quality should be identified and promoted. The primary objective of …

Accuracy And Practical Considerations For Doubly Labeled Water Analysis In Nutrition Studies Using A Laser-Based Isotope Instrument (Off-Axis Integrated Cavity Output Spectroscopy), Linda M. Reynard, William W. Wong, Noreen Tuross

Geosciences Faculty Publications and Presentations

Background: Given the utility of the doubly labeled water (DLW) method for determination of energy expenditure, additional techniques for isotope analysis of the samples are welcome. Laser-based instruments are one such new analytical tool, but their accuracy and feasibility for DLW studies are grossly understudied.

Objectives: We assessed the accuracy of laser-based isotope ratio measurements as part of the DLW method for estimation of carbon dioxide production rate (rCO₂) and total energy expenditure (TEE), in between-group comparison study designs.

Methods: Urine samples from a previous study were analyzed with a laser-based instrument [off-axis integrated cavity output spectroscopy (OA-ICOS)]. …

Mineralogical And Geochemical Signatures Of Weathering On Carbonate Rocks And Dynamic Young Land Surfaces In Muğla Polje (Sw Turkey), Ceren Küçükuysal, Murat Gül, Tural Aghayev, Merve Gülcan

Turkish Journal of Earth Sciences

Red soils as the weathering products in Muğla Polje (SW Turkey) show different occurrences either on hard and permeable limestone (terra rossa (TRs)) or within the matrix of transported sediments (alluvium-derived soils (ALs), alluvium-derived soils specifically from clastics (ALsc), paleosol (Pls), and colluvium-derived soils (CLs)). The purpose of this study is to unlock the effect of weathering on hard carbonate rocks and dynamic young land surfaces (alluvium and colluvium) in Muğla Polje for the first time in terms of mineralogical and geochemical compositions. TRs, the soils of more stable environments are clayey while ALs and CLs as being the soils …

Response Of Soil Biochemical And Physical Properties To Long Term Prairie Cordgrass And Kura Clover Intercropping System, Vaishnavi Varikuti

Electronic Theses and Dissertations

Prairie cordgrass (Spartina pectinata) (PCG) is a warm-season perennial grass that can be used as a biofuel feedstock and can be grown on marginal lands. Previous studies on intercropping of a perennial legume i.e., kura clover (Trifolium ambiguum) (KC) with PCG can improve soil biochemical properties, increase biomass production, mitigate greenhouse gas (GHG) emissions while reducing the chemical fertilizer requirement. However, there is a lack of evidence about the effects of PCG production on soil biochemical and physical properties during the cropping season and at deeper soil depths in reference to support plant growth, environmental implications and enhance the soil …

Spatial Geochemical Changes In Central And East Texas Soils Over Time Resulting From Human Decomposition, Isabela Marisol Overturf

CMC Senior Theses

Human decomposition is studied to aid forensic investigations and better understand the impact of cemeteries on urban resources like soil and groundwater. The purpose of this study was to identify changes in soil geochemistry at and around a human grave to search for lateral nutrient movement and possibly identify new patterns in elemental concentrations that could be used in estimating post-mortem intervals (PMIs). At the Forensic Anthropology Research Facility (FARF) at Texas State San Marcos, soil samples were collected from a shallow grave over the course of 54 days to conduct analysis for organic matter content, texture, pH, and bulk …