Earth Sciences Commons^™

Relation Of Residue Biomass After Defoliation To Regrowth Dry Matter, Wsc And Grain Yield Of Winter Wheat, Lihua Tian, Qingping Zhang, Yuanbuo Liu, Yuying Shen, Lindsay W. Bell, Jeremy P. M. Whish

IGC Proceedings (1977-2023)

The importance of defoliation height on final yield in dual-purpose wheat is inconsistent. In one study no difference in final wheat yield following a severe grazing at 2 cm compared to light grazing at 6 cm was found (Dann et al. 1983). In contrast, clipping at 3 cm above ground level significantly reduced grain yield compared to 7 cm (Arzadun et al. 2006). An explanation for these inconsistent results may be an underestimation of the value of the remaining biomass and its role in the regrowth process (Fulkerson and Donaghy 2001).

In this study, the percentage of residue biomass …

Biological Nitrification Inhibition (Bni) In Brachiaria Pastures: A Novel Strategy To Improve Eco-Efficiency Of Crop-Livestock Systems And To Mitigate Climate Change, Danilo E. Moreta, Jacobo Arango, Mauricio Sotelo, Daniel Vergara, Alvaro Rincón, Manabu Ishitani, Aracely Castro, John Miles, Michael Peters, Joe Tohme, Guntur V. Subbarao, Idupulapati M. Rao

IGC Proceedings (1977-2023)

Up to 70% of the nitrogen (N) fertilizers applied to agricultural systems are lost due to nitrification and denitrification. Nitrification is a microbiological process that generates nitrate (NO₃^-) and promotes the losses of N fertilizers by leaching and denitrification. Nitrification and denitrification are the only known biological processes that generate nitrous oxide (N₂O), a powerful greenhouse gas contributing to global warming. There is an urgent need to suppress nitrification process in soil to improve N-recovery and N use efficiency (NUE) of agricultural systems and to mitigate climate change (Subbarao et al. 2012). Certain Brachiaria …

Describing The Sward Structure Of Wheat And Annual Ryegrass Swards Grazed By Lambs In Southern Nsw, Shawn R. Mcgrath, James M. Virgona, Michael A. Friend

IGC Proceedings (1977-2023)

Dual-purpose wheats are now an established part of the feed base on many mixed-farms in southern NSW. However agronomic practices can vary and it is unknown whether row spacing will impact the availability of forage for grazing by sheep. Intake has been shown to be affected by a range of factors including tiller length, pasture height, sward density and pasture mass (Allden and Whittaker 1970; Black and Kenney 1984). This study sought to describe the differences in sward structure of grazed wheat swards at two different row spacings in terms of mean height, row height and bulk density and compare …

Tiller Size/Density Compensation In Temperate Climate Grasses Grown In Monoculture Or Intercropping Systems Under Rotational Grazing, Paulo G. Duchini, Gabriela C. Guzatti, Henrique M. N. Ribeiro-Filho, João G. R. Almeida, André F. Sbrissia

IGC Proceedings (1977-2023)

From the standpoint of tiller population dynamics, it is well known that the size and numbers of tillers in forage grasses are inversely related, where a greater tiller population density (TPD) is associated with smaller tillers and vice versa (Sbrissia et al. 2003; Hernandez-Garay et al. 1999; Matthew et al. 1995). This relationship has traditionally been made with the self-thinning power law described by Yoda et al. (1963), which considers the leaf area index (LAI) of the pasture constant when the slope of the relationship between numbers and size of tillers, on a logarithmic scale, is …

Under Pressure: Hydraulic Fracturing, Suzanne Miller

Augsburg Honors Review

Modern hydraulic fracturing, or "fracking," is a relatively new technique that has unlocked previously unviable sources of natural gas. It involves the rapid injection of large volumes of fluids into shale formations thousands of feet below the surface to force open fractures, creating pathways for the gas to flow into the well. The recent escalation in fracking operations has already made shale formations a major source of natural gas, but the fracking process could potentially lead to groundwater contamination. This paper explores concerns over the toxic narure of fracking chemicals, the leakage of produced water and natural gas into aquifers, …

Effect Of Fertilizer Level And Intercropping With Bambara Nut (Vigna Subterranea) On The Growth And Herbage Yield Of Maize, Kelechi A. Ike, Leonard C. Nwaigbo, Chioma P. Obasi, Jimoh A. Olanite, Ogechi M. Chilaka

IGC Proceedings (1977-2023)

The low fertility status of most tropical soils has hindered maize production as maize has a strong exhausting effect on the soil. It has been generally observed that maize fails to produce good grain in plots without adequate nutrients (Adediran and Banjoko 2003). Legumes generally are able to fix nitrogen to the soil which the companion crop could benefit from, but usually the nitrogen fixed occurs in insufficient quantities for marginally nitrogen sensitive crops such as maize and hence the required use of fertilizers. Inorganic fertilizers exert strong influences on plant growth, development and yield (Stefano et al. 2004). …

Italian Ryegrass Establishment By Self-Seeding In Integrated Crop-Livestock Systems: Effects Of Grazing Management, Armindo B. Neto, Jean V. Savian, Olivier J. F. Bonnet, Radael M. T. Schons, Paulo C. Vieira, Marcela Santana, José Augusto Q. Díaz, Paulo C. De F. Carvalho

IGC Proceedings (1977-2023)

Recent reports have indicated that integrated crop-livestock systems (ICLS) can enhance sustained crop and livestock production by efficiently using agricultural system resources (Liu et al. 2012). In the subtropical South American regions, soybean (Glycine max L. Merril) and maize (Zea Mays L.) crops are widely grown after Italian ryegrass (Lolium multiflorum Lam) pastures. In this system, the pasture may be established by self-seeding. Self-seedling reduces pasture production costs and extends the grazing period. The stoking method, and especially the grazing intensity, can greatly affect the quantity of seeds added to the soil by affecting the demography …

Development Of Barley Cultivars For Animal Forage In Korea, Ouk-Kyu Han, Tae-Il Park, Tae-Hwa Song, Dea-Wook Kim, Yu-Yong Lee, Ja-Hwan Ku, Jong-Jin Hwang, Chung-Guk Kim, Young-Up Kwon

IGC Proceedings (1977-2023)

In Korea, the domestic consumption of barley as a cereal crop has been decreasing since the 1980s. It has been considered that crop production in the winter-season rice fields could enhance the global competitiveness of domestic livestock industry by providing better quality fodder to livestock and enhancing field use rate. Therefore, the purpose of barley cultivation for cereal food production has been recently replaced by the production of the barley for forage use. Consequently, the area of barley cultivation for forage is markedly increasing in Korea. While any type of barley can be used as forage for feeding cattle, whole …

Animal Production Over Rice-Pasture Rotation System: Animal Performance, R. Cuadro, S. Luzardo, Fabio Montossi, A. Lavecchia

IGC Proceedings (1977-2023)

Fluctuations in commodity prices, determine the need to find strategies to stabilize production in farming systems. The rice - pastures rotation systems are a good example of this, where animal production takes place in the moments where rice is rotated with pastures (3 years rice and 2 years pastures). In this context, INIA has developed a technology adjusted to the east of the country, with the use of "summer tillage" to intensify livestock production through the incorporation of lambs fattening. These technologies, comercially validated with sheep-rice farming systems, can move the process of cattle backgrounding (males and females), but requires …

Mauvais Coulee Basin Hydrologic Data (Observation And Simulation), Diane F. Van Hoy, Taufique H. Mahmood, Paul E. Todhunter, Tyson L. Jeannotte

Datasets

The authors collected snow water equivalent (SWE) data and compiled a hydrologic model for the Mauvais Coulee Basin using Cold Region Hydrologic Platform. The datasets include observed SWE, observed streamflow, simulated SWE, simulated streamflow, simulated SWE maps (Feb 26, Jan 29, Jan 8 and Mar 26 of 2017), land use maps and hydrological representative unit maps (HRU) maps. This study detected a mechanism of hydrologic change to recent wetting using a cold region hydrologic model.

Risk And Cost Assessment Of Nitrate Contamination In Domestic Wells, Pongpun Juntakut, Erin M.K. Haacker, Daniel D. Snow, Chittaranjan Ray

Daugherty Water for Food Global Institute: Faculty Publications

This study combines empirical predictive and economics models to estimate the cost of remediation for domestic wells exceeding suggested treatment thresholds for nitrates. A multiple logistic regression model predicted the probability of well contamination by nitrate, and a life cycle costing methodology was used to estimate costs of nitrate contamination in groundwater in two areas of Nebraska. In south-central Nebraska, 37% of wells were estimated to be at risk of exceeding a threshold of 7.5 mg/L as N, and 17% were at risk of exceeding 10 mg/L as N, the legal limit for human consumption in the United States. In …

Mammoth Onyx Cave - Relating To (Sc 3504), Manuscripts & Folklife Archives

Manuscript Collection Finding Aids

Finding aid and scan (Click on "Additional Files" below) for Manuscripts Small Collection 3504. Letter, 15 August 1922, of Charles A. Richardson, Assistant Geologist, Kentucky Geological Survey, to Dr. Harry B. Thomas, Horse Cave, Kentucky, regarding his recent study of the formations in Mammoth Onyx Cave, then owned by Thomas. He remarks on the “abundance of Mexican Onyx, or Onyx Marble” and the beauty of the stalactites and stalagmites. Includes a pamphlet by Leon Foster with his impressions of the cave, which was opened to the public in 1922.

Initiation Of A Stable Convective Hydroclimatic Regime In Central America Circa 9000 Years Bp, Amos Winter, Davide Zanchettin, Matthew Lachniet, Rolf Vieten, Francesco S. R. Pausata, Fredrik Charpentier Ljungqvist, Hai Cheng, R. Lawrence Edwards, Thomas Miller, Sara Rubinetti, Angelo Rubino, Carla Taricco

Geoscience Faculty Research

Many Holocene hydroclimate records show rainfall changes that vary with local orbital insolation. However, some tropical regions display rainfall evolution that differs from gradual precessional pacing, suggesting that direct rainfall forcing effects were predominantly driven by sea-surface temperature thresholds or inter-ocean temperature gradients. Here we present a 12,000 yr continuous U/Th-dated precipitation record from a Guatemalan speleothem showing that Central American rainfall increased within a 2000 yr period from a persistently dry state to an active convective regime at 9000 yr BP and has remained strong thereafter. Our data suggest that the Holocene evolution of Central American rainfall was driven …

Interactive Tree And N Supply Effect On Root Mass Of Two Annual Pasture Grasses, Laíse Da S. Pontes, Raquel S. Barro, Edemar F. De Camargo, Vanderley P. Da Silva, José L. Moletta, Keli C. S. Guera, Anibal De Moraes, Paulo C. De F. Carvalho

IGC Proceedings (1977-2023)

A major aim of integrated crop livestock system (ICLS) with trees is to increase the overall land productivity and/or its sustainability by making best use of the environmental resources (water, light and nutrients) used by plant for growth (Jose et al. 2008). Consequently, research efforts have been done in order to investigate the complex animal-plant-soils interactions operating upon the biological production of these systems, and their environmental impacts. For instance, since roots return to soil as a stock of C in the soil is in general larger than shoot return, interest in describing plant root system has increased due …

Methane Emissions From Ruminants On Integrated Crop-Livestock Systems, Laíse Da S. Pontes, Raquel S. Barro, Edemar F. De Camargo, Vanderley P. Da Silva, Ian M. Cezimbra, Alexandre Berndt, Cimélio Bayer, Paulo C. De F. Carvalho

IGC Proceedings (1977-2023)

Ruminant livestock produce ~80 million tonnes of methane (CH4) annually, accounting for ~33% of global anthropogenic emissions of CH4 (Beauchemin et al. 2008). CH4 is a powerful greenhouse gas, with global warming potential of 25 (Eckard et al. 2010), and represents a significant loss of dietary energy (2 to 12% of gross energy of feeds; Patra 2012) in the ruminant production system. Despite greenhouse gas (GHG) emissions have become an increasingly important topic worldwide, there is still a high variability around the estimated values of these emissions, mainly about emissions attributable to livestock (range from 8 to 51%; …

Integrating Beef And Cotton Production Reduces Irrigation Needs In The Texas Southern High Plains, C. Philip Brown, V. G. Allen, Rick Kellison, P. Green, C. J. Zilverberg, P. Johnson, V. Acosta-Martinez, C. P. West

IGC Proceedings (1977-2023)

The Texas High Plains is a semiarid agricultural region located in the central south plains of the United States. This area exemplifies semiarid regions where water is becoming scarce. Crop production depends heavily on irrigation primarily from the Ogallala aquifer at non-sustainable rates of use. Irrigated monoculture cotton (Gossypium hirsutum L.) is the dominant crop but grazing livestock in this once vast grassland is re-emerging as the aquifer declines. Environmental benefits of integrated crop and livestock systems have been suggested. We compared a cotton monoculture with an integrated cotton-forage-beef stocker steer system over 10 yr to determine effects on …

Usu Students Win First Asdso Student Dam Model Competition, Utah Water Research Laboratory

News

USU students Kyler Olsen, Braiden Amata, Jack Tousley, Kathryn Margetts, and their Technical Advisor Dr. Brian Crookston recently won the ASDSO’s first student dam model competition.

Integrated Crop Livestock Systems--A Key To Sustainable Intensification In Africa, A. J. Duncan, S. A. Tarawali, P. Thorne, D. Valbuena, Katrien Descheemaeker, Sabine Homann-Keetui

IGC Proceedings (1977-2023)

Mixed crop-livestock systems provide livelihoods for a billion people and produce half the world’s cereal and around a third of its beef and milk. Market orientation and strong and growing demand for food provide powerful incentives for sustainable intensification of both crop and livestock enterprises in smallholders’ mixed systems in Africa. Better exploitation of the mutually reinforcing nature of crop and livestock systems can contribute to a positive, inclusive growth trajectory that is both ecologically and economically sustainable. In mixed systems, livestock intensification is often neglected relative to crops, yet livestock can make a positive contribution to raising productivity of …

Perennial Cereals: A Novel Source Of Feed For Grazing Livestock, Matthew Newell, Richard C. Hayes, Philip Larkin

IGC Proceedings (1977-2023)

Initial deployment of perennial cereal crops will likely be as a dual-purpose crop producing forage for livestock as well as grain. This study evaluated the biomass and grain production of 4 wheat × wheatgrass derivative experimental lines under 4 simulated grazing regimes; nil defoliation (D₀), defoliate once (D₁), defoliate twice (D₂) and defoliate twice followed by a simulated hay cut (D₃), and compared performance to a winter wheat, cv. EGA Wedgetail, and the perennial grass Thinopyrum intermedium. Increasing defoliation intensity significantly (P < 0.001) lengthened the time to flowering for all lines. All experimental lines produced less biomass in the first year than EGA Wedgetail but more than Th. intermedium in the first spring. Grain yield …

New Magnetic Field Models Of The Moon, Dhananjay Ravat, Michael E. Purucker, Nils Olsen

Earth and Environmental Sciences Research Data

We use L1-norm model regularization of |B_r| component at the surface on magnetic monopoles bases and along-track magnetic field differences alone (without vector observations) to derive high quality global magnetic field models at the surface of the Moon. The practical advantages to this strategy are: monopoles are more stable at closer spacing in comparison to dipoles, improving spatial resolution; L1-norm model regularization leads to sparse models which may be appropriate for the Moon which has regions of localized magnetic field features; and along-track differences reduce the need for ad-hoc external field noise reduction strategies. We examine also the …

Re-Growth Yield And Nutritive Value Of Winter Cereals, Gurhan Keles, Serkan Ates, Behic Coskun, Saban Koc

IGC Proceedings (1977-2023)

Cereal crops can be grazed in early winter or early spring when feed is scarce, or to utilize their high feeding value. In the early spring of 2011, the re-growth yield and nutritive value of barley (Hordeum vulgare L.), rye (Secale cereale L.), wheat (Triticum aestivum), oat (Avena sativa L.), and triticale (x Triticosecale Wittmack) grown in the Central Anatolian Region of Turkey, were evaluated after three successive weekly harvests (Cut 1, Cut 2, Cut 3) during the tillering to stem elongation stages. Plants were cut at a height of 5 cm then allowed …

The Role Of Alfalfa And Forage Resources In Crop-Livestock Systems In A Rain-Fed Region Of North-Western China, Yuying Shen, Zhibiao Nan, Fujiang Hou, Lihua Tian, Huimin Yang

IGC Proceedings (1977-2023)

Western China has been facing the challenges of both environmental sustainability and economic development. Current government policies and interventions support the development of integrated crop-livestock production systems for enhancing food security and environment sustainability. Compared with traditional grain-based faming systems, integrated systems have better resource utilisation, however annual forage supply deficits estimated at 1.37 t DM forage/farm are experienced in the region, especially in late winter and early spring. Accordingly, optimising the use of available forage resources is a priority for regional researchers and extension officers, with research seeking pathways for better fodder conservation and greater and more effective use …

A Strategic Approach To Developing The Role Of Perennial Forages For Crop-Livestock Farmers, Rick Llewellyn, Michael Robertson, Richard C. Hayes, David Ferris, Clinton K. Revell, Katrien Descheemaeker

IGC Proceedings (1977-2023)

A substantial proportion of Australian animal production from grazing comes from regions and farms where cropping is the major enterprise. Developing new and improved grazing systems for mixed farms where crop production is the major driver of farm management decisions presents a unique research and development challenge. In this paper we describe a multi-disciplinary farming-systems research approach (‘EverCrop’) aimed at improving farm profitability, risk management and environmental impacts through the development and integration of new grazing options. It has been used to analyse and target new opportunities for farmers to benefit from perennial species across dry Mediterranean-type and temperate regions …

Do Multi-Paddock Systems Increase Evenness Of Grazing At The Paddock Scale?, Robyn A. Cowley, Ian A. White, Mark H. Hearnden, Leigh Hunt, Steve P. Petty, Lindy Symes

IGC Proceedings (1977-2023)

There is ongoing debate about the benefits of multi-paddock rotationally grazed systems compared to continuous grazing (Briske et al. 2008). One of the purported benefits of high density short duration grazing is more spatially uniform defoliation. A commercial-scale trial in northern Australia (Hunt et al. 2013) compared continuously grazed paddocks to cell grazed and wet season spelled systems in newly developed paddocks. This paper reports the effect of grazing system on defoliation with distance to water through time.

Drivers Of Pasture Growth In Perennial Ryegrass Pastures In Northern New Zealand Dairy Pastures, Natalie R. Mapp, Grant M. Rennie, Warren Mcg. King

IGC Proceedings (1977-2023)

The critical importance of pasture production to New Zealand’s economic performance has been widely recognised. However, a number of critical issues have been identified that limit dairy industry growth, including sub-optimal pasture condition and poor pasture persistence. Dairy farm systems in the Waikato and Bay of Plenty provinces in the upper North Island of New Zealand are predominantly pasture-based, with a temperate climate and they represent around 30% of New Zealand’s total number of dairy farms (LIC and DairyNZ, 2012). This project was established to quantify pasture performance and identify factors that drive that performance. We established a network of …

Extending The Period Of High Feed Value In Italian Ryegrass (Lolium Multiflorum Lam.) For Grazing In The Warm Temperate Zone Of Japan, Makoto Kaneko, Yoshi-Nori Nakamura, Akihisa Yamada

IGC Proceedings (1977-2023)

Japan has widely diverse climate conditions, from subtropical in the south to boreal in the north. In warm regions of the temperate zone in the south-west, such as low-lying areas of Kyushu Island, temperate grasses only barely survive during the summer (Area V in Fig. 1). Therefore, for year-round grazing, tropical grasses and temperate grasses have been used, respectively, for summer and winter (Fig. 2). Throughout Japan, grazing is limited for cows and their calves and fattening takes place in barns. Recently, as consumer preference for meat has diversified, the demand for lean meat with less fat from grazing cattle …

Early Sowing And Irrigating Of Rape Crops In Cool Temperate Environments Boosts Forage Yield Potential, Matthew T. Harrison, Keith G. Pembleton, Richard P. Rawnsley

IGC Proceedings (1977-2023)

Forage rape is commonly grown on Tasmanian dairy farms to provide feed during periods of low pasture growth and/or low nutritive value. In these regions, forage crops are generally sown between early spring and late autumn and are commonly rainfed, though farmers may apply a single irrigation at sowing. While the effect of water availability on forage yield has been well characterised for regions in north-western Tasmania (Neilsen 2005), there is a dearth of information for other regions in Tasmania. Hence, the objectives of this study were to identify optimal sowing times for, and determine the extent to which a …

Aboveground Biomass And Soil Moisture As Affected By Short-Term Grazing Exclusion In Eastern Alpine Meadows Of The Qinghai-Tibet Plateau, China, Haibo Liu, Jianping Wu, Wen Wang, Xiaoli Jin, Zhenheng Liu, Wenhua Du

IGC Proceedings (1977-2023)

Heavy grazing substantially influences grassland vegetation and animal nutrition on the Qinghai-Tibet plateau (Guo et al. 2003). Degradation is characterized by a reduction in vegetation height, reduced ground cover decrease in species diversity (Wang et al. 2007).

The objective of this study was to determine the effects of short-term exclusion from grazing on aboveground herbage, forage nutritive value, and soil moisture in an alpine meadow in the eastern zone of the plateau. Three farms, applying different intensity of grazing over the summer months, were compared.

Performance Of Anatolian Merino And Akkaraman Lambs Fed Triticale, Hungarian Vetch Or A Mixture Of The Two Forages, Serkan Ates, Gurhan Keles, Fatma Inal, Ahmet Gunes, Mounir Louhaichi

IGC Proceedings (1977-2023)

Forages from Hungarian vetch and triticale monocultures or mixtures that can be produced with relatively low cost are important feed sources for ruminants in spring particularly in the arid and semiarid regions. The feed intake and the response of different sheep breeds (Fraser et al. 2009) to forage resources that vary in feeding value may differ. Therefore it is critical to match forage to animal and crop production needs for more efficient production in integrated crop livestock farming system.

Plant Biomass And Bovine Live Weight Changes In Mono-Specific And Mixed Pastures During The Rainy Season In Dry Tropical Mexico, Régulo Jiménez-Guillén, Adrián R. Quero-Carrillo, Pedro A. Martínez-Hernández, Alfonso Hernández-Garay

IGC Proceedings (1977-2023)

Dry tropics suffer long drought periods each year, negatively affecting the amount and digestibility of forage for cattle production. The aim of this study was evaluate different pasture types, grazed by cattle during the rainy season. Three hectares were prepared to compare: grass monoculture, Andropogon gayanus (G); a grass-legume mixture of A. gayanus and Clitoria ternatea (GL), and a grass-legume-tree mixture of A. gayanus, C. ternatea and Morus alba (GLT). Two grazing cycles (4 d grazing followed by 32 d resting; 72 d total) were completed. Three heifers (average initial weight 192 kg) grazed each experimental unit. The amounts …