Physical Sciences and Mathematics Commons^™

Biophysical, Grazing-Season Management, And Animal Traits Effects On Individual Animal Performance Of Cow-Calf Systems: Insights From A Long-Term Experiment In The Us Western Great Plains, G. Irisarri, P. A. Cipriotti, L. Castro Sardiña, M. Mortenson, J. D. Derner

IGC Proceedings (1997-2023)

Beef grazing systems require information on management, biophysical, and individual animal influences on performance metrics. However, long-term controlled experiments are lacking to comprehensively ascertain these individual and likely interacting influences. We used a legacy data set from the USDA Agricultural Research Service where individual weight gains were determined from on and off weights of Hereford cows and calves grazing native northern mixed-grass prairie, during the June through September season, from 1975-2001 near Cheyenne, Wyoming, USA. The herd size varied from a minimum of 10 to a maximum of 48 pairs across years. Management (on and off grazing dates and stocking …

Germination And Seedlings Heterotrophic Growth Of Cocksfoot (Dactylis Glomerata L.) In Response To Temperature, Abraham Escobar-Gutiérrez, L. Q. Ahmed

IGC Proceedings (1997-2023)

In the context of climate change, grasslands are considered, similar to forest, as an important sink for atmospheric CO₂. However, environmental change seems to go faster than species adaptation to survive on site. Germination and heterotrophic growth are key phases for plant, and consequently, communities’ establishment and structure. They are under genetic control and affected by temperature. The objective of this study was to analyze the intra-specific variability of six accessions of Dactylis glomerata in their responses to eight constant temperatures (5 to 40˚C) during germination and initial heterotrophic growth. The novelty of this work comes from the …

L-Grassf: A New Model For Simulating The Genetic Environment Interactions On The Reproductive Phenology Of Grasses, S. Rouet, Jean Louis Durand, D. Combes, A. Escobar Gutiérrez, D. Leclercq, R. Barillot

IGC Proceedings (1997-2023)

Predicting the reproductive phenology in perennial grasses is a major concern because it determines the quantity and quality of forage. It varies a lot depending on site, year and cultivar. Projections of future climates suggest significant changes in seasonal temperature pattern, with new combinations of temperature and photoperiod, whose consequences on the floral induction of perennial grasses are unknown. L-GrassF is a new Functional Structural Plant Model simulating genetic variability of the phenology of perennial ryegrass in order to better understand the perenniality of grasslands and better anticipate the effects of climate change. L-GrassF stems from a previous model (L-Grass) …

An Examination Of The Diurnal Variability In Nitrous Oxide Emissions, B. P. Hyde, A. F. Fanning, M. Ryan, O. T. Carton

IGC Proceedings (1997-2023)

It is generally assumed in field experiments, that the measurement of nitrous oxide (N₂O) using enclosed chambers for a period of 1 hour can be used to provide an estimate of daily emission rates. In the majority of studies, emission measurements are conducted between 0900 and 1300 h. However, clearly defined diurnal cycles in N₂O emission rates have been observed from both agricultural and forest soils in temperate regions as a consequence of diurnal fluctuations in temperature (Blackmer et al., 1982; Ball et al., 1999; Baggs et al., 2002). The objective of this …

Net Photosynthesis Rate And Chlorophyll Content Of Caucasian And White Clover Leaves Under Different Temperature Regimes, A. D. Black, R. J. Lucas, D. J. Moot

IGC Proceedings (1997-2023)

In spring and summer in intensive temperate pastures, Caucasian clover (Cc) (Trifolium ambiguum) has higher dry matter (DM) production rates than white clover (wc) (Trifolium repens) (Black et al., 2003). An examination of the physiological basis for these differences can provide a greater insight into the suitability of Cc for inclusion in temperate pastures. Specifically, leaf photosynthesis rate is a major driver of seasonal growth and is strongly regulated by temperature and chlorophyll content. This study aimed to compare the net photosynthesis rate (Pn) and chlorophyll content of Cc and wc leaves under different temperature …

How Soil Properties Affect Egg Development And Larval Longevity Of A Grassland Insect Pest - An Empirically Based Model, S. N. Johnson, X. Zhang, J. W. Crawford, P. J. Gregory, S. C. Jarvis, P. J. Murray, I. M. Young

IGC Proceedings (1997-2023)

The clover root weevil (Sitona lepidus Gyllenhal.) is a destructive pest of white clover in temperate grasslands. Adults lay thousands of eggs that give rise to soil-dwelling larvae that initially feed on the root nodules housing symbiotic N2-fixing Rhizobium spp. bacteria. The period between egg hatch and consumption of root nodules by larvae is probably the most vulnerable part in the lifecycle, and if larvae do not locate roots relatively quickly they will die of starvation. In particular, the shells of eggs and the cuticles of emergent larvae are in constant physical contact with the external soil environment, so …

Are Soybean Models Ready For Climate Change Food Impact Assessments?, Kritika Kothari, Rafael Battisti, Kenneth J. Boote, Sotirios V. Archontoulis, Adriana Confalone, Julie Constantin, Santiago V. Cuadra, Philippe Debaeke, Babacar Faye, Brian Grant, Gerrit Hoogenboom, Qi Jing, Michael Van Der Laan, Fernando Antônio Macena Da Silva, Fabio R. Marin, Alireza Nehbandani, Claas Nendel, Larry C. Purcell, Budong Qian, Alex C. Ruane, Céline Schoving, Evandro H. F. M. Silva, Ward Smith, Afshin Soltani, Amit Srivastava, Nilson A. Vieira Jr., Stacey Slone, Montserrat Salmerón

Plant and Soil Sciences Faculty Publications

An accurate estimation of crop yield under climate change scenarios is essential to quantify our ability to feed a growing population and develop agronomic adaptations to meet future food demand. A coordinated evaluation of yield simulations from process-based eco-physiological models for climate change impact assessment is still missing for soybean, the most widely grown grain legume and the main source of protein in our food chain. In this first soybean multi-model study, we used ten prominent models capable of simulating soybean yield under varying temperature and atmospheric CO₂ concentration [CO₂] to quantify the uncertainty in soybean yield …

Grasslands Classification In Yobe State Nigeria Using Integrated Orderly Classification System Of Grassland (Iocsg), S. Usman, M. G. Bala, Y. Shen

IGC Proceedings (1997-2023)

Integrated Orderly Classification System of Grassland (IOCSG) was initiated by Professor Ji-Zhou Ren in the 1960s and it has satisfactorily served to direct theory and practice of grassland classification for the last several decades in China. In this study IOCSG is adopted to classify the grasslands in Yobe state Nigeria, using 30 years (1984-2013) data on precipitation and temperature from 12 satellite stations across the state. Humidity (moisture index) was estimated as the ratio of precipitation per annum to annual temperature. The results revealed a trend of decline in precipitation and moisture index with latitude; from 772.63 mm and 0.72 …

Effects Of Dry Matter Content And Microbial Additive On Tifton 85 (Cynodon Dactylon Ssp.) Wilted Silage Fermentation Parameters, Luiz Gustavo Nussio, F. G. Castro, J. M. Simas, C. M. Haddad, P. Toledo, A. L. Merchan

IGC Proceedings (1997-2023)

The objective of this study was to evaluate the wilting and the addition of a bacterial-enzymatic additive effects on the fermentation parameters of Tifton 85 (Cynodon dactylon spp.) silage. Forage was stored as 326 kg bales wrapped with a plastic film. Treatments consisted of 5 forage dry matter levels (20-30%, 30-40%, 40-50%, 50 -60% e 60 a 70%) without additive and 3 dry matter levels (20-30%, 40-50%, e 60-70%) with additive. Buffered propionic acid solution was sprayed onto 60-70% dry matter bales, prior to wrapping, determining an additional treatment. Core samples were taken at 0, 6, 12 hours …

Forage Quality And The Environment, C. E. Lascano, A. Schmidt, R. Barahona

IGC Proceedings (1997-2023)

The influence of environmental factors on forage quality of temperate and tropical grasses has been reviewed by several authors, who summarized how light, temperature, drought and soil nutrients influence chemical composition, and digestibility of forages grown in contrasting areas of the world. The effects of season of the year on forage growth, grazing behavior and animal performance have also been the subject of numerous papers and reviews. However, there are few recent reviews that summarize how changes in climatic and edaphic factors influence forage quality of legumes with variable levels of condensed tannins (CT), which are important secondary compounds in …

Effects Of Photoperiod, Low Temperature And N Nutrition On Vsp Accumulation In Taproot Of Alfalfa, J. C. Avice, C. Noquet, A. Ourry, J. J. Volenec

IGC Proceedings (1997-2023)

In Medicago sativa L., vegetative storage protein (VSP), specifically accumulated in taproot, are strongly involved in nitrogen storage. How the accumulation of such VSPs is regulated remains largely unknown. Experiments were designed with non-nodulated alfalfa to determine if length of the photoperiod, a decrease of temperature, or high availability of mineral nitrogen may induce the accumulation of VSPs. ¹⁵N labelling was used to quantify nitrogen uptake and its further relative translocation within the plant while VSPs accumulation was analysed by ELISA quantification. Results showed that environmental factors such as shortening daylength or low temperature changed biomass allocation within the …

Influence Of Salinity And Temperature On The Germination And Seedling Growth Of Chloris Virgata Swartz, Hongxiang Zhang, Daowei Zhou, Yu Tian

IGC Proceedings (1997-2023)

No abstract provided.

Germination Characteristics Of Haloxylon Bunge Seeds, L. R. Tong, J. G. Han

IGC Proceedings (1997-2023)

No abstract provided.

Influence Of Seasonal Changes And Variety On The Water‐Soluble Carbohydrate (Wsc) Content Of Varieties Of Lolium Perenne In Sweden, Magnus A. Halling

IGC Proceedings (1997-2023)

No abstract provided.

The Impact Of Temperature On Seed Germination In Diverse Accessions Of 4 Wild Vigna Species, Yanrong Wang, J. Hanson

IGC Proceedings (1997-2023)

No abstract provided.

Effect Of Temperature Changes On Germination Of Three Range Grass Species And Implication For Their Conservation, E. C. Kirwa, W. N. Mnene, E. N. Muthiani, P. Mweki

IGC Proceedings (1997-2023)

No abstract provided.

Investigation Of Affecting Some Climatic Factors On Distribution Of Plant Societies In Eastern Alborz (Ir‐Iran), Mohammadreza Tatian, Muhammad Ali Bahmanyar, Reza Tamartash, Hamid Jalilvand

IGC Proceedings (1997-2023)

No abstract provided.

Infrared Heater Arrays For Warming Grazingland Field Plots, Bruce A. Kimball, Matthew M. Conley, Shiping Wang, Xingwu Lin, Caiyun Luo, Jack Morgan, David Smith

IGC Proceedings (1997-2023)

No abstract provided.

Stability Of Alpine Meadow Ecosystem On The Qinghai‐Tibetan Plateau, Huakun Zhou, Xinquan Zhao, Li Zhou, Wei Liu, Yingnian Li, Song Gu, Xinmin Zhou

IGC Proceedings (1997-2023)

No abstract provided.

Composting Characteristics Of Bovine Manure Produced By Conventional Stacked Processing And An Experimental Small-Scale Apparatus, Yusuke Kajiya, Yasuyuki Ishii, Kiichi Fukuyama, Sachiko Idota

IGC Proceedings (1997-2023)

Southern Kyushu is an important center of beef production in Japan and the large amounts of bovine waste that are produced in the region need to be utilized in a way that is not harmful to the environment. One such method is to use the manure to produce organic fertilizer, which can then be used to replace the chemical fertilizer that is used for forage production (Hasyim et al., 2014). The composting of bovine manure involves co-digestion of cow manure with substrates such as sawdust and hay. The composting characteristics of these mixtures are influenced by the relative amounts of …

Development Of Greenhouse Dryer For Forage Conservation In Temperate Climate, Sanjay Kumar Singh, P. K. Pathak

IGC Proceedings (1997-2023)

Greenhouse dryer implies drying of crops in covered structure that allows rapid harvesting of solar radiation and modification of agro climatic conditions conducive for proper drying. The environmental factors which affects plant growth includes air temperature, relative humidity, light, carbon dioxide concentration, soil temperature and moisture content of soil. The greenhouse may have heating, cooling and ventilating equipments for control over microclimates. Control over microclimate results in several fold increase in crop photosynthesis, and optimum thermal energy for forage conservation in the form of hay.

Chandra et al. (2002) have proposed the design of a naturally ventilated greenhouse. Several other …

Global Land Carbon Sink Response To Temperature And Precipitation Varies With Enso Phase, Yuanyuan Fang, Anna M. Michalak, Christopher R. Schwalm, Deborah N. Huntzinger, Joseph A. Berry, Philippe Ciais, Shilong Piao, Benjamin Poulter, Joshua B. Fisher, Robert B. Cook, Daniel Hayes, Maoyi Huang, Akihiko Ito, Atul Jain, Huimin Lei, Chaoqun Lu, Jiafu Mao, Nicholas C. Parazoo, Shushi Peng, Daniel M. Ricciuto, Xiaoying Shi, Bo Tao, Hanqin Tian, Weile Wang, Yaxing Wei, Jia Yang

Plant and Soil Sciences Faculty Publications

Climate variability associated with the El Niño-Southern Oscillation (ENSO) and its consequent impacts on land carbon sink interannual variability have been used as a basis for investigating carbon cycle responses to climate variability more broadly, and to inform the sensitivity of the tropical carbon budget to climate change. Past studies have presented opposing views about whether temperature or precipitation is the primary factor driving the response of the land carbon sink to ENSO. Here, we show that the dominant driver varies with ENSO phase. Whereas tropical temperature explains sink dynamics following El Niño conditions (r TG,P = 0.59, p …