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A Diagnostic Framework For Reengineering Soil: Potential Strategies To Manage Combinations Of Soil Constraints For Sands And Texture Contrast Soils, Gaus Azam, Stephen Davies

Natural resources published reports

This report is an output of project DAW1902-003RTX ‘Reengineering soils to improve the access of crop root systems to water and nutrients stored in the subsoil’, supported by a co-investment between the Department of Primary Industries and Regional Development (DPIRD) and the Grains Research and Development Corporation (GRDC).

Key messages:

• Existing soil amelioration options can generate substantial yield responses. However, further yield gain is possible with further improvement in soil amelioration strategies.

• Mapping of soil constraints and potential yield gaps using the water use efficiency achieved from a pilot reengineering experiment has identified a significant yield gap attributed …

Cascading Effects Of Cover Crops On The Subsequent Cash Crop Defense Against The Polyphagous Herbivore Fall Armyworm (Spodoptera Frugiperda), Adegboyega Fajemisin, Alexis Racelis, Rupesh R. Kariyat

School of Earth, Environmental, & Marine Sciences Faculty Publications

Simple Summary

Although studies have started to show that the effects of cover crops can translate into the cash cropping season, there is little information on the cascading effects of cover crops on the subsequent cash crop defenses, especially against polyphagous herbivores. To bridge this information gap, we conducted a field and laboratory study to investigate the cascading effects of different cover crop species on the subsequent cash crop defense against the polyphagous herbivore fall armyworm (Spodoptera frugiperda) across three fields in the Lower Rio Grande Valley in south Texas. Our field and laboratory results revealed that cover crop treatments …

Evaluation Of Polyacrylamide (Pam) Effects On Irrigation Efficiency, Soil Conservation, And Water Quality In Midsouth Cotton Production, Brittany D. Barnes

Student Theses and Dissertations

The polymer, polyacrylamide (PAM), is a high molecular weight, chemical anionic polymer that is prescribed and used for irrigation improvement in row crops primarily in the United States. A field research study was conducted in 2014, 2015 and 2016 in Northeast Arkansas to evaluate how addition of PAM in furrow irrigation affected soil erosion, water infiltration, movement of nutrients and sediments, and crop yields in cotton (Gossypium hirsutum). Overall results from the study were mixed. Sediment loss was similar among treatments. Irrigation advancement rates were not significantly different. No differences in crop yield were observed associated with PAM. Differences in …

Wayne E. Sabbe Arkansas Soil Fertility Studies 2022, Nathan A. Slaton, Mike Daniels

Arkansas Agricultural Experiment Station Research Series

Rapid technological changes in crop management and production require that the research efforts be presented in an expeditious manner. The contributions of soil fertility and fertilizers are major production factors in all Arkansas crops. The studies described within will allow producers to compare their practices with the university’s research efforts. Additionally, soil-test data and fertilizer sales are presented to allow comparisons among years, crops, and other areas within Arkansas.

Water Resources, Agriculture And Pasture: Implications Of Growing Demand And Increasing Scarcity, M. W. Rosegrant, R. A. Valmonte-Santos, S. A. Cline, C. Ringler, W. Li

IGC Proceedings (1977-2023)

1. Water availability for irrigation is threatened in many regions by rapidly increasing demand for nonagricultural water uses in industry, households, and the environment. The scarcity of irrigation water will not only impact crop production, but also meat production, as much of the pasture used to feed livestock is irrigated.
2. Grassland is caught between two countervailing forces: a requirement for increasing meat demand that boosts the need for additional pasture to support livestock production, and rapidly increasing water scarcity that makes pasture irrigation uneconomical.
3. The most effective means of dealing with water scarcity is likely to be conserving water in existing …

Grasses As Biofactories: Scoping Out The Opportunities, Nick Roberts, K. Richardson, G. Bryan, Christine R. Voisey, W. Mcnabb, T. Conner, M. Christey, R. Johnson

IGC Proceedings (1977-2023)

1. Plant biopharming is set to dominate commercial recombinant protein expression for specific proteins.
2. The choice of plant species depends on a multitude of factors and is determined on a case- by-case basis.
3. As a leaf based expression system grasses would have to compete predominantly with tobacco and alfalfa.
4. The grass-endophyte symbiosis offers a number of unique possibilities for biopharming.

Adoption Of Tropical Legume Technology Around The World: Analysis Of Success, H. M. Shelton, Steven Franzel, M. Peters

IGC Proceedings (1977-2023)

1. Examples of successful adoption of forage legumes are reported from all continents, where they delivered profitability and often provided multipurpose benefits to farmers.
2. Factors vital to successful adoption were: meeting the needs of farmers; building relevant partnerships; understanding the socio-economic context and skills of farmers; participatory involvement with rural communities; and long-term involvement of champions.
3. Organisation of seed supply, achieving scale-up and forming partnerships to implement adoption are key features.
4. Legumes remain an important but under-exploited resource for tropical farming systems. The alternative to legumes will be greater and more costly use of N-fertilisers and purchased protein concentrates.
5. The R&D …

Evolution Of Integrated Crop-Livestock Production Systems, Martin H. Entz, William D. Bellotti, J. M. Powell, S. V. Angadi, W. Chen, K. H. Ominski, B. Boelt

IGC Proceedings (1977-2023)

1. Many factors contribute to changes in the crop-livestock systems, but no logical end-point in the evolution process exists.
2. While benefits of integrated crop-livestock systems over specialised crop and livestock systems are well documented, there has been a move to specialised crop and livestock production.
3. Sustainability issues (manure nutrient concentration, soil quality maintenance, salinity, herbicide resistance, economic instability) have created a renewed interest in integrated crop-livestock systems.
4. Farmer adaptability is as an important link in the evolution between ‘states of integration’.

Overcoming Seasonality Of Production: Opportunities Offered By Forage Conservation Technologies, P. O'Kiely, A. G. Kaiser

IGC Proceedings (1977-2023)

1. Seasonality of forage supply is a key contributor to the seasonality of meat and milk production.
2. Conserving forages as silage or hay can help reduce the seasonality of feed supply.
3. Forage conservation technologies make this contribution mainly through increases in the yield or quality of suitable crops, through an improved efficiency of the conservation process or by allowing a reduction in costs.
4. Future research needs differ considerably among regions of the world.

Strategies To Mitigate Seasonality Of Production In Grassland-Based Systems, Claudio Porqueddu, S. Maltoni, J. G. Mcivor

IGC Proceedings (1977-2023)

1. Fertilisation use and manipulation can cost-effectively alter species composition, increase seasonal herbage production and improve herbage quality.
2. Choice of suitable grassland species, varieties and mixtures offers opportunity to mitigate limitations of seasonal grassland production.
3. Special purpose fodder crops, cereals, shrubs and trees offer alternative or supplementary feed sources.
4. Manipulation of stocking rates, grazing systems, transhumance and pasture management at various times of the season are significant advantageous options.
5. Integration of different strategies is essential to mitigate seasonality in systems of animal production that must be inherently more sustainable over a longer time frame.

Interactions Between Foraging Behaviour Of Herbivores And Grassland Resources In The Eastern Eurasian Steppes, Deli Wang, Guodong Han, Yuguang Bai

IGC Proceedings (1977-2023)

1. In rangeland areas such as the eastern Eurasian steppes (Mongolia and China), foraging behaviour is influenced by plant or vegetation properties with high heterogeneity.
2. Until recently foraging theory has not accounted for the foraging process or ingestive behaviour. Existing theories on foraging behaviour need to evolve and begin to coalesce, and combine with observations or manipulative experiments.
3. Plant and patch properties such as diversity and height influence animal foraging behaviour (related to foraging process or diet selection) in heterogeneous steppes.
4. Stocking rate is the most important management factor for grazing or vegetation management, and determining the optimal stocking rate in …

Foraging Behaviour And Herbage Intake In The Favourable Tropics/Sub-Tropics, S. C. Da Silva, Paulo C. De F. Carvalho

IGC Proceedings (1977-2023)

1. Herbage intake by animals grazing tropical/sub-tropical pastures is directly related to bite mass, as it is for those grazing temperate pastures.
2. Where these swards have low proportions of stem and dead material (controlled swards), herbage intake follows a similar pattern to that of temperate pasture species, but leaf characteristics, such as lamina length play an important role and influence the short-term rate of intake.
3. Sward structural characteristics and behavioural factors are relatively more important than nutritional factors in terms of herbage intake regulation. The feeding value of the herbage produced is potentially adequate to sustain high levels of beef cattle …

Regenerative Agriculture - A Literature Review On The Practices And Mechanisms Used To Improve Soil Health, Ravjit Khangura, David Ferris, Cameron Wagg, Jamie Bowyer

Natural Resources Research Articles

Conventional farming practices can lead to soil degradation and a decline in productivity. Regenerative agriculture (RA) is purported by advocates as a solution to these issues that focuses on soil health and carbon sequestration. The fundamental principles of RA are to keep the soil covered, minimise soil disturbance, preserve living roots in the soil year round, increase species diversity, integrate livestock, and limit or eliminate the use of synthetic compounds (such as herbicides and fertilisers). The overall objectives are to rejuvenate the soil and land and provide environmental, economic, and social benefits to the wider community. Despite the purported benefits …

Improving The Quality Of Products From Grassland, Nigel D. Scollan, R. J. Dewhurst, A. P. Moloney, J. J. Murphy

IGC Proceedings (1977-2023)

1. Consumers are increasingly aware of the links between diet and health, and place increasing emphasis on nutritional quality as a component of product quality.
2. Meat and milk products are rich sources of nutrients such as omega-3 (n-3) fatty acids and conjugated linoleic acid, which offer health benefits to consumers.
3. Green plants are the primary source of n-3 fatty acids in the food chain.
4. Grassland production systems have the potential to enhance the content of beneficial fatty acids, improve stability (from higher antioxidant content) and alter sensory attributes of meat and milk.
5. Grassland offers considerable scope to help …

Grass And Forage Improvement: Temperate Forages, Chris J. Pollock, M. T. Abberton, M. O. Humphreys

IGC Proceedings (1977-2023)

1. Plant breeding has contributed significantly to the development of effective grassland production systems.
2. New technologies offer enhanced precision in breeding and access to wider genetic variation.
3. The requirement for more sustainable production systems will require genetic improvements in complex traits where the use of new technology will be vital.

Rising Demand For Meat And Milk In Developing Countries: Implications For Grasslands-Based Livestock Production2, C. L. Delgado

IGC Proceedings (1977-2023)

1. Meat and milk consumption in developing countries has grown three times as fast as in developed countries over the past 30 years.
2. By 2020, developing countries will consume 72 million metric tons (mmt) more meat and 152 mmt more milk compared to 2002/3, dwarfing developed-country increases of 9 mmt for meat and 18 mmt for milk.
3. Ruminant livestock will account for 27% of the increase in global meat consumption between 2003 and 2020, up from 23% over the previous two decades.
4. The inflation-adjusted prices of livestock and feed grains are expected to fall only marginally by 2020, compared to precipitous …

Grassland In Ireland And The Uk, Myles Rath, S. Peel

IGC Proceedings (1977-2023)

1. Grassland is the dominant land use option in Ireland and the UK, and is characterised by a long growing season.
2. Dynamic, interactive systems of grassland management have been developed which combine high grass dry matter intakes with good sward quality. In the better grassland areas milk yields in excess of 7000 kg/cow are attainable with low levels of concentrate supplementation. In the times to come, measures to protect the environment will constrain stocking rates, and fertiliser and manure use on intensive grassland enterprises.
3. A high proportion of beef and sheep farms participate in voluntary, EU-funded agri- environmental schemes that promote …

How Herbivores Optimise Diet Quality And Intake In Heterogeneous Pastures, And The Consequences For Vegetation Dynamics, R. Baumont, Cécile Ginane, F. Garcia, P. Carrère

IGC Proceedings (1977-2023)

Understanding the interplay between foraging behaviour and vegetation dynamics in heterogeneous pasture is an essential requirement for evaluating the value of the resource for large herbivores and for managing that resource. The orientation of selective grazing behaviour between intake and diet quality depends on the spatial and temporal scales considered. In the short-term scale of a grazing sequence, there is evidence that large herbivores tend to optimise the intake rate of digestible materials by adaptation of their biting behaviour and by patch choice. On a day-to-day scale, there is evidence that large herbivores tend to prioritise the quality of the …

Challenges And Opportunities For Sustainable Rangeland Pastoral Systems In The Edwards Plateau Of Texas, J. W. Walker, J. L. Johnson, C. A. Taylor Jr.

IGC Proceedings (1977-2023)

This paper focuses on pastoral systems in an area of west-central Texas known as the Edwards Plateau. These rangelands have a combination of grass, forb and browse species and are used primarily for combinations of grazing by cattle, sheep, goats and wildlife. A major ecological challenge is woody plant encroachment. Stocking rate is the major factor affecting sustainability and historically this area was heavily grazed. Today the stocking rate is half or less of its historical peak. Species of livestock has shifted from predominantly small ruminant to cattle. About 70 % of pastoralists use some sort of rotational grazing system. …

Diversity And Variation In Nutritive Value Of Plants Growing On 2 Saline Sites In Southwestern Australia, H. C. Norman, R. A. Dynes, D. G. Masters

IGC Proceedings (1977-2023)

In south-western Australia 10% or 1.8 million ha of the farmed area is affected by dryland salinity and a further 6 million ha are at risk of salinity (NLWRA, 2001). Animal production from saltbush (Atriplex spp.)-based pasture systems represents the most likely large-scale opportunity for productive use of saline land in the short to medium term. Feeding saltbush-based pastures as a maintenance feed during the prolonged autumn feed gap typical in Mediterranean-type climates maximises their economic value. The aim of this study was to explore the diversity and nutritive value of plants that typically persist in saltbush-based saltland pastures.

The Long Road To Developing Native Herbaceous Summer Forage Legume Ecotypes, J. P. Muir, T. J. Butler, W. R. Ocumpaugh

IGC Proceedings (1977-2023)

Only a handful of well-adapted herbaceous summer forage legumes are currently marketed for drier regions of North America and even fewer are true natives. There is a growing demand for native germplasm in the region as a new generation of landowner attempts to return grasslands to a semblance of their original species and diversity. The objective of this paper is to describe preliminary research results of a grasslands team collecting, studying and promulgating native leguminous germplasm in Texas.

Selecting Grassland Species For Saline Environments, M. E. Rogers, A. D. Craig, T. D. Colmer, R. Munns, S. J. Hughes, P. M. Evans, P. G. H. Nichols, R. Snowball, D. Henry, J. Deretic, B. Dear, M. Ewing

IGC Proceedings (1977-2023)

In Australia, around 5.7 million hectares of agricultural land are currently affected by dryland salinity or at risk from shallow water tables and this figure is expected to increase over the next 50 years (LWRA, 2001). Most improved grassland species cannot tolerate the combined effects of salt and waterlogging and, therefore, the productivity of sown grasslands in salt-affected areas is low. However, there is potential to overcome the lack of suitably adapted fodder species by introducing new, salt and waterlogging-tolerant species and by diversifying the gene pool of proven species. Potential species include exotic, naturalised and native Australian grass, legumes, …

Grazing Animal Production Systems And Grazing Land Characteristics In A Semi-Arid Region Of Greece, I. Hadjigeorgiou, G. Economou, D. Lolis, N. Moustakas, G. Zervas

IGC Proceedings (1977-2023)

Rough grazing in Greece cover about 40% of the total land area, is publicly owned and managed extensively (Hadjigeorgiou et al., 2002). The Prefecture of Larisa is in the centre of Greece, and has 212,000 ha of rough grazing land, with a variable topography ranging from sea level up to 3,000 m a.s.l. This area is utilized by a total population of 135,000 LU (mainly sheep, goats and some suckler cows), which consumes annually an appreciable fraction of their total nutrient requirements from rough grazing.

The Productivity Of Coastal Meadows In Finland, R. Nevalainen, S. Jaakola, A. Huuskonen, J. Kiljala, E. Joki-Tokola

IGC Proceedings (1977-2023)

The coastal meadows of Finland have gained a new interest as a summer pasture for cattle. These habitats have great historical, aesthetic and biological value (Pessa & Anttila, 2000). Typical features of the coastal meadows are the varying vegetation zones and wet, sometimes waterlogged, soils. The meadows are important nesting and feeding habitats for many water birds. When grazing ceases, reeds, trees and shrubs take over and the area loses its openness. Lately the amount of grasslands and pastures has drastically declined all over Europe. In Finland, the area of semi-natural biotopes has decreased to 1% of what it had …

Grass And Forage Plant Improvement In The Tropics And Sub-Tropics, Liana Jank, C. B. Do Valle, Rosangela M. S. Resende

IGC Proceedings (1977-2023)

1. The majority of tropical and subtropical forage grass genera and/or species have not yet been collected, or need further collection to be representative of their natural distribution.
2. New biotechnological techniques will only result in the release of superior forage cultivars if supported by strong breeding programs.
3. More funding and investment in the formation of strong public research teams in forage conservation and improvement are needed to guarantee the sustainability of tropical and subtropical pasture-based livestock systems in the future.
4. The creation of a permanent international working group on tropical and subtropical forages is essential to assist the International Plant Genetic …

Role Of Social Determinants Of Health In Differential Respiratory Exposure And Health Outcomes Among Children, Jagadeesh Puvvula, Jill A. Poole, Yeongjin Gwon, Eleanor G. Rogan, Jesse E. Bell

Daugherty Water for Food Global Institute: Faculty Publications

Background Attributes defining the Social Determinants of Health (SDoH) are associated with disproportionate exposures to environmental hazards and differential health outcomes among communities. The dynamics between SDoH, disproportionate environmental exposures, and differential health outcomes are often specific to micro-geographic areas.

Methods This study focused on children less than 20 years of age who lived in Douglas County, Nebraska, during 2016–2019. To assess the role of SDoH in differential exposures, we evaluated the association between SDoH metrics and criteria pollutant concentrations and the association between SDoH and pediatric asthma exacerbations to quantify the role of SDoH in differential pediatric asthma outcomes. …

Sheep Ingestive Behavior And Tannin Selection In Pampa Grassland And Feedlot, Marina Terra Braga

Green Canyon Environmental Research Area, Logan Utah

The Pampa grassland biome has high plant biodiversity, some with significant secondary compound concentrations such as tannins. Tannin inclusion in ruminant diets may improve meat quality and productivity. However, voluntary intake of this phenolic compound can be a challenge. This dissertation includes three studies within this context. The first study documented whether sheep consume tannin-rich Desmodium incanum (DI), the most common Pampa herbaceous legume species. The second study evaluated how forage tannin and protein concentration influenced sheep feedlot feed selection and the diet affects performance parameters. The third study evaluated sheep feeding behavior in a Pampa native pasture, and how …

Determining Mating Type And Species Of A Natural Isolate Of Dictyostelium Using Molecular Techniques And Sexual Crosses, S.N. Baviskar, C. Catron, H. Jenkins, M. Smith

Journal of the Arkansas Academy of Science

Cellular slime molds, Dictyostelium, are bactivorous, soil-dwelling amoebae. When food is available, cells reproduce asexually by binary fission. Under certain environmental conditions, such as darkness and humidity, Dictyostelium reproduces sexually. The sexual cycle is uniquely social and has unusual features. First, sexual reproduction in most eukaryotes usually involves fusion of two gametes. But, in Dictyostelium, triparental inheritance is observed (Bloomfield et al. 2019), in which gamete fusion involves more than two gametes. Second, most eukaryotic species have two sexes or mating types, but Dictyostelium species are known to have more than two mating types. Even though Dictyostelium species show variations …

Keynote Address And Meeting Program, Academy Editors

Journal of the Arkansas Academy of Science

No abstract provided.

Pithonellid Calcitarch Record In The Middle? Cenomanian Derdere-A Member, Se Turkey: Palaeoenvironmental Changes And Stratigraphic Significance, Oğuz Mülayi̇m, İsmai̇l Ömer Yilmaz, Bruno Ferré

Turkish Journal of Earth Sciences

Pithonellid calcitarchs are studied in the organic-rich limestones of the Derdere-A Member from the middle? Cenomanian deposits of SE Turkey for the first time. Little is known about the distribution of pithonellid calcitarchs in the Cretaceous strata of Turkey. Three morphogroups of pithonellid calcitarchs are distinguished: they are represented by Pithonella sphaerica (Kaufmann, 1865) and P. ovalis (Kaufmann, 1865), both dominating the pithonellid assemblages, and by Bonetocardiella conoidea (Bonet, 1956), this latter being less abundant. Compared to the relative abundance of Upper Cretaceous pithonellid calcitarchs in the study area, the diversity is extremely low. The significant increase in abundance of …