Soil Science Commons^™

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 …

Land Use History And The Build-Up And Decline Of Species Richness In Scandinavian Semi-Natural Grasslands, O. Eriksson, S. A. O. Cousins, R. Lindborg

IGC Proceedings (1977-2023)

Scandinavian semi-natural grasslands have an exceptionally high small-scale species richness. In the past, these grasslands covered extensive areas but they have declined drastically during the last century. How species richness of semi-natural grasslands was built up during history, and how species respond to land use change, are discussed. The agricultural expansion from the late Iron Age was associated with increasing grassland extent and spatial predictability, resulting in accumulation of species at small spatial scales. Although few species directly depend on management, the specific composition of these grasslands is a product of haymaking and grazing. Grassland fragmentation initially has small effects …

Recreating Pastoralist Futures, T. J. P. Lynam

IGC Proceedings (1977-2023)

Research experience in southern Africa is used to reflect on key determinants of pastoral futures and how they might need to be addressed. The paper begins with a brief review of what we mean by marginality. A set of observations on key issues defining the option sets for pastoralism in the future is then presented. The first of these is that only a small number of structures or processes actually control the behaviour of social-ecological systems such as pastoralist systems. A second observation is that the future is so uncertain that there is a need to learn to design for …

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. …

Working Within Constraints: Managing African Savannas For Animal Production And Biodiversity, J. T. Du Toit

IGC Proceedings (1977-2023)

The mean density of livestock biomass on African rangelands now greatly exceeds that of indigenous large herbivores, although livestock cannot fully substitute for wildlife with respect to co-evolved ecosystem processes involving herbivory. The dominance of livestock in semi-arid rangelands is largely due to water provision, which uncouples livestock population dynamics from the rainfall-driven trajectories followed by indigenous ungulate species in wildlife areas. Ecological sustainability cannot be achieved with a few exotic species maintained at unprecedented biomass densities in savanna ecosystems, which are evolutionarily adapted for species-rich communities of ungulates of a wise range of sizes. Integrating wildlife and livestock in …

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.

Mortality Model For A Perennial Grass In Australian Semi-Arid Wooded Grasslands Grazed By Sheep, K. C. Hodgkinson, W. J. Muller

IGC Proceedings (1977-2023)

No abstract provided.

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 …

Dinitrogen Emissions Dominate Nitrogen Gas Emissions From Soils With Low Oxygen Availability In A Moist Tropical Forest, Maya Almaraz, Peter M. Groffman, Whendee L. Silver, Steven J. Hall, Yang Lin, Christine S. O'Connell, Stephen Porder

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Lowland tropical forest soils are relatively N rich and are the largest global source of N₂O (a powerful greenhouse gas) to the atmosphere. Despite the importance of tropical N cycling, there have been few direct measurements of N₂ (an inert gas that can serve as an alternate fate for N₂O) in tropical soils, limiting our ability to characterize N budgets, manage soils to reduce N₂O production, or predict the future role that N limitation to primary productivity will play in buffering against climate change. We collected soils from across macro- and micro-topographic gradients …

Organic Matter Content And Grain Size Analysis In Seagrass Sediments, Adriana Amrhein, Rip Hale

College of Sciences Posters

Anthropogenic stresses including increased water temperatures, decreased water quality, sea level rise, ocean acidification and sediment biogeochemical processes have caused a significant loss in seagrass meadow acreage. Seagrass meadows provide coastal protection from storms and recently have been emphasized for their importance in sequestering and storing “Blue Carbon” from the atmosphere and ocean. Seagrass meadows can trap this blue carbon in their sediment as organic carbon, and it can be stored for hundreds to thousands of years. Restoration efforts of seagrass meadows in the Virginia coast started in the 1990s and effects of increasing seagrass density can be observed in …

Cover Crop Composition In Long-Term No-Till Soils In Semi-Arid Environments Do Not Influence Soil Health Measurements After One Year, Hunter Bielenberg, Jason D. Clark, Debankur Sanyal, Johnathon Wolthuizen, David Karki, Amin Rahhal, Anthony Bly

Agronomy, Horticulture and Plant Science Faculty Publications

Evaluating the influence of grass or broadleaf cover crops on soil health measurements is common in the northern US Midwest. However, the comparison among different cover crop mixtures, including blends of both grass and broadleaf species is limited. In 2018–2020, cover crop experiments were conducted in South Dakota at 11 site-years. Cover crops were planted in the summer after small grains harvest as mixtures of dominantly grasses or broadleaves, a 50/50 grass/broadleaf mixture, and a no cover crop control. Soil and above-ground plant residue samples were collected in the fall before winter termination and in the spring before corn planting. …

A Participatory Drone Mapping And Critical Physical Geography Of Water Security For Irrigation In Northern Ghana, Dinko Hanaan Dinko

Electronic Theses and Dissertations

Dam discourse frequently incorrectly assumes that their emergence unilinearly translates to an expansion of economic opportunities while not considering how dams become sites for the reproduction of inequality and injustice. This dissertation investigates how the politics of irrigation water access are nested in a complex web of physical materialities of the 'natural' environment and power relations, with lived consequences on differentiated social identities in semiarid Ghana. The research draws on transdisciplinary perspectives from political ecology, embodiment, critical physical geography, and mixed methods, including interviews, focus group discussions, surveys, participatory drone mapping, and laboratory analysis of soil biochemical properties. The study …

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 …

Abiotic Stress Mitigation: A Case Study From 21 Trials Using A Natural Organic Matter Based Biostimulant Across Multiple Geographies, Rachel L. Sleighter, Terry Hanson, David Holden, Kristen M. Richards

Chemistry & Biochemistry Faculty Publications

Crop productivity and yields can be greatly diminished by abiotic stress events including drought, extreme temperatures, excess moisture, and saline irrigation water. Multiple stressors occurring simultaneously can further exacerbate the strain on plants. Various types of biostimulants have been shown to mitigate abiotic stress and here, the results of 21 trials on corn, wheat, soybean, and various high-value crops are discussed in the context of the abiotic stress that either occurred naturally or was experimentally induced. Treatments in these trials included stressed and non-stressed plants, as well as either an untreated control or grower standard fertilizer applications alone and in …

Implications Of Intraspecific Variation In Soil Microbes On Solidago Performance, Yazeed Alshammari

Masters Theses

This study explored the implications of intraspecific variation in soil microbes on the performance of Solidago altissima, a North American species that has become invasive across several continents. This research explored how different clones of Solidago altissima were associated with bacterial and fungal soil microbial communities, which influenced plant performance. In a common garden of 24 Solidago altissima clones, I analyzed the relationship between soil microbial communities, foliar chemistry, clone genetic relatedness, and plant performance. My methods included analysis of soil microbial communities (bacterial and fungal), genetic distances among clones to assess relatedness, and measures of plant performance (light …

Tracking Nitrogen Mineralization In The Presence Of Biochar Utilizing Complementary-Method Assays In East Central South Dakota, Andrew Calvin Engel

Electronic Theses and Dissertations

Understanding soil N transformations in agricultural systems of the Northern Great Plains is crucial for guiding effective soil and nutrient management of this vital cropland. While the use of biochar in agriculture has attracted great attention recently, little has been reported on the seasonal dynamics of soil nitrogen (N) transformation and its response to biochar application. A field experiment was conducted over 2 seasons, spring (6/3/19-6/24/19) and summer (7/26/19-8/16/19), using four treatments or control soil, urea (224 kg N/ha), biochar (46,250 kg/ha), and urea+biochar (224 kg N/ha and 46,250 kg/ha, respectively). The results for both seasons showed biochar had no …

Quantifying The Carbon Stored And Sequestered By The Trees On Pomona College’S Campus, Paola A. Giron-Carson

Scripps Senior Theses

We are experiencing a climate crisis that must be confronted with strategic mitigation. Pomona College contributes to the climate crisis through its emissions for which there is a baseline record. However there is no baseline record of the climate mitigation currently performed by the trees on Pomona’s campus through carbon storage. This study seeks to determine a current baseline quantity of carbon stored and sequestrated by Pomona’s trees as well as possible courses of climate mitigation for Pomona College to take. Initial information gathering was conducted through interviews with several stakeholders. This study was conducted using data collected prior to …

Using Soil And Forest Type To Map Bedrock In Nemo, South Dakota, Madison R. Isaac

Williams Honors College, Honors Research Projects

Bedrock mapping can be used to locate economic deposits, assess natural disaster (e.g., mass wasting) risk, and decipher the geologic history of a region. This study examines a site at Nemo, South Dakota to assess whether two contrasting types of bedrock produce different soil that result in different types of forest cover. Although bedrock varied, other soil forming factors were uniform. Within an approximately 1 km² area, quartzite and metagabbro bedrock, ponderosa pine and quaking aspen forests were mapped. The soil above the quartzite bedrock is thinner and sandier and is dominated by ponderosa pine (Pinus ponderosa). …

Soil And Compost Tea: A New Restoration Technique?, Carol E. Day

Master's Theses and Doctoral Dissertations

Historically, prairie restorations have lacked the plant diversity seen in remnant prairies. Most restoration practices focus on reestablishing the plant community but overlook the soil microbial community even though microbes are critical to habitat functioning. Developing techniques that increase soil microbes in prairie restorations is critical to ensuring diverse restored habitats. We compared how microbial communities differed between remnant and restored prairie sites. We also investigated if soil and compost teas could be used to reintroduce microbes to restored prairie soil and if the teas affected native plant establishment. We found significant differences in the levels of bacterial taxa between …

Estimating Evapotranspiration And Analyzing Soil Moisture And Heat Flux Parameters At Taneum Creek, Central Washington, Edward Vlasenko

All Master's Theses

In the past two decades, stream restoration work, primarily in the form of wood emplacement, has been undertaken in the Taneum Creek watershed, resulting in increased channel-floodplain connectivity. One of the goals of stream restoration was to boost dry season groundwater storage in the shallow floodplain aquifer. However, any gains in groundwater due to increased connectivity may be nullified by increased evapotranspiration (ET) losses because of denser floodplain vegetation. Within the floodplain aquifer budget, ET is a major flow of water out of the system and is not well quantified.

In order to quantify ET, a monitoring site was established …

Towards Sweetness Classification Of Orange Cultivars Using Short‑Wave Nir Spectroscopy, Ayesha Zeb, Waqar Shahid Qureshi, Abdul Ghafoor, Amanullah Malik, Muhammad Imran, Alina Mirza, Mohsin Islam Tiwana, Eisa Alanazi

Articles

The global orange industry constantly faces new technical challenges to meet consumer demands for quality fruits. Instead of traditional subjective fruit quality assessment methods, the interest in the horticulture industry has increased in objective, quantitative, and non-destructive assessment methods. Oranges have a thick peel which makes their non-destructive quality assessment challenging. This paper evaluates the potential of short-wave NIR spectroscopy and direct sweetness classification approach for Pakistani cultivars of orange, i.e., Red-Blood, Mosambi, and Succari. The correlation between quality indices, i.e., Brix, titratable acidity (TA), Brix: TA and BrimA (Brix minus acids), sensory assessment of the fruit, and short-wave NIR …