Physical Sciences and Mathematics Commons^™

Sunn Hemp As An Alternative Forage In The Texas High Plains Region, S. A. O’Shaughnessy, H. M. Mosqueda, D. K. Brauer

IGC Proceedings (1997-2023)

Forage production in the Texas High Plains, a semi-arid region, is critical to sustain the local cattle industry. However, the main source of water for irrigation is the highly depleted Ogallala Aquifer, making forage crop water productivity (CWP) of high importance. In this one-year study, three types of forages were cultivated under deficit irrigation treatments of 80% and 50% of full crop water use. The forages were: a non-brown midrib forage sorghum; a legume, sunn hemp; and a sorghum/sunn hemp mix. The experiment was conducted in Bushland, Texas in 2019. Treatment plots were arranged in a split plot design with …

Differences In Carbon Sequestration And Water Use Between A Semi-Arid Native Grassland And Encroaching Vachellia Karroo Woodland, C. Weideman, A. R. Palmer, G. Carolyn, Kathleen Smart

IGC Proceedings (1997-2023)

Tree and shrub encroachment and proliferation in global grasslands and savannas is widely considered to imply a trade-off between ecosystem C and H2O regulating functions, based on the premise that increased C sequestration associated with higher woody biomass ostensibly drive declines in water production through concomitant increases in evapotranspiration (ET), but evidence for this across climatic and environmental gradients is equivocal. To evaluate these claims, we ran a paired eddy covariance experiment in a native semi-arid C4 grassland and adjacent encroaching Vachellia karroo woodland on the eastern seaboard of South Africa and compared ecosystem C and H2O budgets over nearly …

Effects Of Stocking Rates On Water Use Efficiency Of Established Species In Stipa Breviflora Desert Steppe, M. Zhao, G. M. Yin, S. B. Liu, W. J. Meng

IGC Proceedings (1997-2023)

Plant water use efficiency reflects the survival adaptation strategies adopted by plants to obtain maximum carbon harvest. Understanding the water and resource utilization strategies of Stipa breviflora in desert steppe will help people understand its growth mechanism, and it is of great significance to analyze the ecological countermeasures of Stipa breviflora to cope with disturbance. In this study, the water use efficiency (WUE) of the established populations of Stipa breviflora in desert steppe was measured by stable carbon isotope method and photosynthometer method, and the adaptation mechanism of Stipa breviflora under different stocking rates was discussed based on the basic …

Irrigation Effects On Forage Dry Matter Yield And Nutritive Value Of Alfalfa, Rudra Baral, Doohong Min

IGC Proceedings (1997-2023)

Alfalfa (Medicago sativa L.) is among the top four field crops in United States (U.S.) in terms of acreage harvested and economic value. Several studies have documented that alfalfa requires high amount of water compared to other major field crops. However, more than 65% alfalfa in the U.S. is grown under rainfed condition where severe to moderate drought condition has been pronounced during alfalfa growing season. The magnitude of yield loss due to water-limited conditions is still unknown. In this context, the objective of our study is to evaluate the forage dry matter yield and forage nutritive value of …

Potential Of Indigenous Desert Grasses For Forage Production In A Water-Scarce Region, A. E. Osman

IGC Proceedings (1997-2023)

Indigenous perennial grasses are widely distributed in the Arabian Peninsula. Their survival under limited rainfall and grazing suggests a potential role as grassland species and for rehabilitation of degraded rangelands. Forage productivity and water-use efficiency (WUE) was determined over 2 years for four indigenous grasses: buffel grass (Cenchrus ciliaris L.), dakhna (Coelachyrum piercei Benth.), da’ay (Lasiurus scindicus Henr.) and tuman (Panicum turgidum Forssk.) together with one exotic species, rhodes grass (Chloris gayana Kunth) in the central region of the United Arab Emirates. Three irrigation treatments were used: R1 (1858–6758 m³ ha^-1 year^{-1 …}

Balancing Water Use Efficiency And Milk Production In The Sub-Tropics, Mark N. Callow, S. K. Kenman

IGC Proceedings (1997-2023)

Queensland dairy farmers have had to confront in the last 5 years deregulation of the milk pricing system, resulting in a 25% reduction in farm gate price for milk in the year 2000, and drought. Many storage dams are significantly below capacity and regulatory authorities have imposed restrictions on irrigation water allocations. Major changes in farm business strategies were needed to overcome the shortfall in milk income. Production systems had to change to deliver more milk more efficiently and become more profitable. A farmlet study was developed in the sub-tropical dairy region of Queensland to evaluate 5 very different farm …

Improvement Of Native Perennial Forage Plants For Sustainability Of Mediterranean Farming Systems, F. Lelièvre, Florence Volaire

IGC Proceedings (1997-2023)

The amount of water available to agriculture in the Mediterranean is declining because of increasing population pressure and greater incidence of drought. Therefore, the efficiency of the use of water for agricultural production must be maximized and, in this context, perennial forage species have a number of advantages in comparison to the predominantly-used annuals. They can utilize water throughout the whole year besides being able to halt rangeland degradation, restore soil fertility and enhance forage production, thereby contributing to greater sustainability of rain-fed agricultural systems in the southern European Union and North Africa. Despite these advantages, the small size of …

Performance Of Napier Grass (Cenchrus Purpureus L.) Genotypes Grown Under Limited Soil Moisture, E. Habte, M. S. Muktar, A. T. Negawo, A. M. Sartie, C. S. Jones

IGC Proceedings (1997-2023)

Napier grass (Cenchrus purpureus Schumach L.) is an important perennial forage native to Africa and grown in many tropical and subtropical countries. It is considered as a short-term drought tolerant forage which is a useful trait in areas that are characterized by low precipitation during the dry season. To exploit the potential of this grass and identify water use efficient (WUE) genotypes, a field drought stress trial was conducted at Bishoftu, Ethiopia. Eighty-four Napier grass genotypes were planted in a p-rep design in four replications. The genotypes were evaluated for forage performance during the dry season of 2019 and …

Increasing Precipitation Decreases Water Use Efficiency Of Alfalfa (Medicago Sativa L.) In A Semiarid Region, H. Ni, H. K. Chu, X. F. Lai, J. Q. Deng, Yuying Shen

IGC Proceedings (1997-2023)

Alfalfa (Medicago sativa L.) plays an important role within the integrated farming systems in Northwestern Loess Plateau of China, because of its traits on a high productivity, prolonged growing season, and excellent nutritive value. However, water use efficiency (WUE) is a crucial indicator for forage production under different water conditions in the semiarid regions. To explore the responses of alfalfa growth and water use to precipitation variability, we set precipitation shelters to manipulate precipitation scenario as 30% precipitation increased (P+30), normal precipitation (CK), and 30% precipitation decreased (P-30) with the measurement of dry matter yield and soil water content. …

Irrigation Management Strategies For Fodder Beet (Beta Vulgaris L.) Crops, Edith N. Khaembah, John M. De Ruiter, E. Chakwizira, S. Maley, M. J. George

IGC Proceedings (1997-2023)

The production of fodder beet (Beta vulgaris L.) in New Zealand is concentrated in the South Island, and often requires irrigation to achieve high yields. Development of efficient irrigation management strategies requires information on the effect of timing and rate of irrigation on crop growth. A field study was conducted on a moderately deep soil at Chertsey, Canterbury, New Zealand, to evaluate crop growth responses to five irrigation managements: Rain-fed (control), weekly replacement of full evapotranspiration (FullET-weekly), and 50% of evapotranspiration replaced weekly (HalfET-weekly), fortnightly (HalfET-2weekly) or 3-weekly (HalfET-3weekly). Irrigation to replace ET was adjusted to account for rainfall …

Carbon Isotope Discrimination, Selection Response, And Forage Production Of Tall Fescue In Contrasting Environments, R. C. Johnson, Andrew A. Hopkins, M. A. Evans

IGC Proceedings (1997-2023)

No abstract provided.

Effects Of Single Irrigation On Yield And Wue Of Siberian Wildrye Grass In Agro‐Pastoral Transition Zone Of China, Hao Wang, Zizhong Li, Zhongyan Wang, Ding Huang

IGC Proceedings (1997-2023)

No abstract provided.

Level Of Water Stress Substantially Affects Productivity And Water Use Efficiency Of 30 Forages Used By The Australia Dairy Industry, James Neal, William Fulkerson, Roy Lawrie

IGC Proceedings (1997-2023)

No abstract provided.

Water Use Indices Of Tropical Perennial Grasses In A Temperate Environment, Sean R. Murphy, G. M. Lodge, M. A. Brennan

IGC Proceedings (1997-2023)

No abstract provided.

Growth And Water Use Of Perennial Ryegrass And Tall Fescue Under Different Irrigation Treatments, R. J. Martin, Trevor L. Knight, R. N. Gillespie, M. U. Riddle, Tom J. Fraser

IGC Proceedings (1997-2023)

No abstract provided.

Digitaria Eriantha Under Water Deficiency, H. Laborde, M. B. Toribio, M. N. Fioretti, R. E. Brevedan, S. S. Baioni

IGC Proceedings (1997-2023)

No abstract provided.

Effect Of Silicon Application On Water Use Efficiency Of Alfalfa Plants, Zhenggang Guo, Huixia Liu, Suomin Wang

IGC Proceedings (1997-2023)

No abstract provided.

Effects Of Air Velocity On Eco‐Physiological Characteristics Of Some Common Herb Species In Horqin Sand Land, Inner Mongolia, China, G. Y. Yue, H. L. Zhao, H. Qu, L. Niu

IGC Proceedings (1997-2023)

No abstract provided.

Photosynthesis And Biomass Studies In Lasiurus Sindicus Of Chandan Grassland In Thar Desert, P. Raja, Maharaj Singh, Nilendu Singh, Nawalesh Kumar Sinha

IGC Proceedings (1997-2023)

Grasslands comprise about one third of the world’s area of natural vegetation (Adams et al., 1990). Uncertainties prevail in the arid ecosystem with reference to carbon balance and fluxes which are primarily attributed to the sensitivity of grasslands to variation in annual precipitation, temperature and other regulating mechanisms of eco-physiological processes (Flanagan et al., 2002). It is therefore necessary to study radiation and water use efficiency of Lasiurus sindicus which is a predominant grass species in Chandan grassland of Thar desert to understand and evaluate its growth in relation to variation in climate. Also, it is pertinent to resolve …

Production And Resource Use Of Winter Feed Crops In New Zealand, John De Ruiter, E. Chakwizira, S. Maley

IGC Proceedings (1997-2023)

In the South Island of New Zealand (NZ), dairy cow numbers have increased from 1.4 to 2.1 million since 2005 (Statistics, New Zealand, 2014). This has led to a strong demand for winter feed crops in place of pasture, and also for supplementing pasture during lactation. Yields of 19–35 t DM/ha are reported for fodder beet (Beta vulgaris L.) in NZ (Chakwizira et al., 2014) compared with 14–25 t DM/ha for forage kale (Brassica oleracea L.) (Chakwizira et al., 2009) and 18–25 t DM/ha for maize (Zea mays L.). Fodder beet has only recently been …

Water Use Efficiency And Evapotranspiration Of Hybrid Napier (Pennisetum Purpureum X P. Americanum) Under Semi-Arid Indian Region, J. B. Singh, Rajiv K. Agrawal, Pradeep Behari

IGC Proceedings (1997-2023)

Napier bajra hybrid (Pennisetum glaucum x P. purpureum) is a highly valued for its abundant quality forage, round the year fodder availability, regenerative ability and suitability to silage and hay making. It yields upto 110-120 t/ha fresh fodder as sole crop. Though, it requires moist regimes for optimum growth, but it can withstand drought for a short spell and regenerate with rains. It contains 8.7-10.2 % crude protein, 28-30.5% crude fibre and 10-11.5 % ash on dry matter basis (Agrawal et al., 2001). The hybrid napier has wider adaptability and is grown all over the country, …

Alteration Of Physiological Parameters Of Milkvetch (Astragalus Adsurgens) By The Pathogen Embellisia Astragali, Binhua Yu, Zhibiao Nan

IGC Proceedings (1997-2023)

Milkvetch (Astragalus adsurgens) is sown on > 1 M ha in China as a forage legume and to control soil and water erosion. It is drought-tolerant and has high herbage yield, wide adaptability and medium forage quality. However, fungal disease is a major factor affecting its persistence and productivity. Embellisia astragali is a highly virulent seed-borne pathogen which commonly causes stunt and root rot. The objective of this study was to characterize the impact of Embellisia astragali on the physiological status of milkvetch by monitoring changes through time in net photosynthesis, stomatal conductance and other parameters of milkvetch inoculated …

Photosynthetic And Growth Response Of Triodia Pungens To Elevated Co2 Concentration, Lisa Xian, Susanne Schmidt, Fernanda Dreccer, Paul Memmott

IGC Proceedings (1997-2023)

Triodia (“spinifex”) is a widely distributed endemic C4 grass genus in Australia. Triodia species form the hummock grasslands which is one of Australia’s dominant vegetation types covering approximately 30% of the continental land mass in the arid zone. Hummock grasslands are commonly used as rangelands and Triodia plays an important role in the ecosystem by providing habitat for arid fauna and maintaining arid lands vegetated.

Currently, Triodia survive extreme temperatures, water deficit and low nutrient availability. Predicted changes for Australia’s arid climate under elevated atmospheric CO₂ (eCO₂) include reduction in rainfall and higher daily average temperatures in …

Photosynthetic Response Of Two Caragana Species To The Stimulated Climate Change In Mu Us Sand Land Of Northwest China, Zhirong Zheng, Yubao Gao, Shihai Lu

IGC Proceedings (1997-2023)

Due to human activities, the concentration of carbon dioxide (CO₂) in the Earth’s atmosphere is rising rapidly. The atmospheric CO₂ concentration has increased to 360 μmol/mol from 280 μmol/mol at the end of the 19th century, and it will be doubled in the late 21st century (Alcamo 1996). Since CO₂ is a key factor for plant growth and development, much more attention has been paid to the effect of an elevated atmospheric CO₂ concentration on many ecosystem processes (Hungate et al. 1997; Idso et al. 1992; Oren et al. 2001; Sun et …

Evaluation Of Crop Production And Water Use Efficiency Of Autumn-Sown Annual Forage Crops On The Rainfed Region Of Loess Plateau China, Qingping Zhang, Lihua Tian, Yuanbo Liu, Lindsay W. Bell, Jeremy P. M. Whish, Yuying Shen

IGC Proceedings (1997-2023)

The Loess Plateau is one of the most important rainfed regions in China, but rainfall is the most significant factor limiting crop production. In this region rainfall from July to September accounts for 56% of the annual total, providing enough water resources for the growth of autumn-sown crops. Although increasing forage production with autumn sown crops is considered an important means of balancing crop forage and livestock management, suitable species with high yields and good water use efficiency (WUE) are not well defined.

The relationship between yield and water use efficiency has been shown to vary with plant species and …

Integration Of Hydrogeophysical Datasets For Improved Water Resource Management In Irrigated Systems, Catherine E. Finkenbiner

School of Natural Resources: Dissertations, Theses, and Student Research

Water scarcity is predicted to be the major limitation to increasing agronomic outputs to meet future food and fiber demands. With the agricultural sector accounting for 80 – 90% of all consumptive water use and an average water use efficiency (WUE) of less than 45%, major advances must be made in irrigation water management. Precision agriculture, specifically variable-rate irrigation (VRI) and variable-speed irrigation (VSI) systems, offers the technologies to address and manage for infield variability and incorporate that into management decisions. The major limitation to implementing this technology often lies in the management of spatial datasets and the development of …

Slides: Water Management In Spain, Teodoro Estrela

Coping with Water Scarcity in River Basins Worldwide: Lessons Learned from Shared Experiences (Martz Summer Conference, June 9-10)

Presenter: Teodoro Estrela, Júcar River Basin Authority, Spain

15 slides

Slides: Food Production: Technical Challenges In Agricultural Water Conservation, Perry Cabot

Innovations in Managing Western Water: New Approaches for Balancing Environmental, Social and Economic Outcomes (Martz Summer Conference, June 11-12)

Presenter: Dr. Perry Cabot, Research Scientist and Extension Specialist, Colorado Water Institute, Colorado State University

35 slides

Slides: Economic Incentives For Demand Reduction, Christopher Goemans

Western Water Law, Policy and Management: Ripples, Currents, and New Channels for Inquiry (Martz Summer Conference, June 3-5)

Presenter: Christopher Goemans, Department of Agriculture & Resource Economics, Colorado State University

17 slides

Producing Pulses In The Northern Agricultural Region, Peter White, Martin Harries, Mark Seymour, Pam Burgess

Bulletins 4000 -

Pulses, like most other temperate crops, are ideally suited to environments with mild temperatures, adequate rainfall and free draining soils that have a deep uniform profile, a medium to fine texture and slightly acid to neutral pH (6.5-7.5). Pulses when grown on these soils and in these environments produce reliable yields, are relatively easy to manage and achieve good returns on investment.

Pulses can be grown very successfully in less ideal situations, but must then be managed carefully to ensure reliable yields. The different pulse species, and even different varieties of the same species, vary in how tolerant they are …