Earth Sciences Commons^™

Climatology Of Tornadoes In Kansas, John P. Wasinger, Todd Moore

SACAD: Scholarly Activities

Recent studies report changes to the climatology of tornadoes in the United States (US). Changes with the most supporting evidence include an increase in the intra- and inter-annual variability, increased concentration of tornadoes in bigger outbreaks, and a geographic shift of the densest tornado activity away from Tornado Alley in the Great Plains and toward the Great Lakes and Southeast regions of the US. Broad, national-level changes are valuable, but they can mask changes occurring at the state and sub-state levels where mitigation efforts are most effective. Kansas is of interest due to its reputation as a hotbed of tornado …

Revolutionizing Ecosystems: Innovative Planting Machines Combating Desertification, Sunghun Park, Jeanne Sumrall

SACAD: Scholarly Activities

An important environmental issue that has a profound effect on human welfare, socioeconomic stability, and global ecosystems is desertification. A little over 12 million hectares of land perish year due to the damaging impacts of desertification, which is made worse by overgrazing, deforestation, and inadequate water management. This not only results in a significant loss of arable land, capable of producing 20 million tons of grain, but also in substantial economic repercussions, with estimated annual losses reaching USD 42 billion (UNCCD, 2020). The enormity of the problem emphasizes how urgently we need practical, long-term solutions to stop and reverse the …

Assessing Unstable Fossils For Long-Term Storage, Carson Cope, Alex Landwehr, Kale Link, Israel Rivera-Molina, Laura E. Wilson

SACAD: Scholarly Activities

In 2022, Fort Hays State University’s Sternberg Museum of Natural History (FHSM) began a project to address the long-term preservation of a Late Miocene mammal collection. Many of the fossils from the collection were poorly consolidated, uncurated, and improperly stored, leaving them unstable and prone to significant degradation. To organize our stabilization efforts, we developed a new assessment workflow consisting of two evaluation tools. These tools have helped us categorize the risk factors for specimens, the priority in which they should be addressed, and how to store the fossils long-term. With these newly developed workflows, we are in a better …

Investigation Of Temporal Variation In Sediment Deposition Within The Tropical Wouri Estuary Cameroon Using Fourier Transform Infrared Spectroscopy, Olumide Ajulo, Dr. Henry Agbogun, Dr. Hendratta Ali

SACAD: Scholarly Activities

In this study, Fourier Transform Infrared Spectroscopy (FTIR) was employed to qualitatively analyze organic and mineral components of the sediment core collected from the Wouri Estuary. The FTIR spectra revealed distinct transmittance corresponding to different organic and mineral phases, allowing for the characterization of sediment composition. The FTIR spectra showed changes and variation progressively from the bottom to the top. These sediments are proxies for time this can be inferred to say deposition in the Wouri Estuary has always changed.

Qualitative Analysis Of Selected Hydrocarbon Produced In Kansas Using Ftir: An Oil-Oil Correlation Study, Oluwaseun Omoyemi, Henry Agbogun, James Titah

SACAD: Scholarly Activities

Hydrocarbons have been produced in Kansas since the 1860s, however, the properties and characteristics of the produced oil are still poorly understood.

An oil-oil correlation analysis has been conducted on twelve hydrocarbon samples from three subbasins and from five producing intervals within the State of Kansas. Fourier Transform Infrared Radiation (FTIR) was used to characterize the organic functional groups present within the samples and Thin Layer Chromatography (TLC) was used to assess the hydrocarbon fractions in the samples. The FTIR spectrum of all the samples exhibit similar peaks implying similar functionally groups were present in all the samples. The TLC …

Developmental Characteristics And Renovating Pattern Of Reed Canarygrass Shoots In A Sward, M Ito, S Mizuno, T Otani, S Kobayashi

IGC Proceedings (1977-2023)

Developmental and renovating traits of shoots were investigated ecomorphologically in a reed canarygrass (Phalaris arundinacea L., cv. Palaton) sward harvested 3 times per year. Reed canarygrass shoots exhibited notably high growth rates both in the 1st and 2nd crops together with rapid leaf formation (around 7 days/leaf) and active internode elongation. Vigorously growing shoots, which regenerated soon after the 1st cutting and dominated in the 2nd crop canopy, mainly originated from the stubble formed with 3 to 4 phytomers that developed after the beginning of spring growth, thus resulting in higher shoot density than that of the 1st crop. …

Canopy Changes In Healthlands (Erica-Ulex) Grazed By Sheep Or Goats, R Celaya, K Osoro

IGC Proceedings (1977-2023)

The grazing effects of sheep and goats on vegetation dominated by heaths (Erica spp) and gorse (Ulex gallii) were studied for two years. Two plots were grazed from May to October 1992 by 7 ewes or 7 does and in the following year each plot was subdivided into two subplots subsequently grazed either by sheep or by goats in a factorial design. During the first grazing season both sheep and goats reduced similarly the cover percentage of shrubs since the herbaceous content was scarce, although goats reduced more the height of the shrubs than sheep. The cover …

Effect Of Nitrogen, Phosphorus, Potassium And Cutting On The Regrowth And Insect Infestation Of A Sorghum And Berseem Clover In Egypt, M B. Attia

IGC Proceedings (1977-2023)

The objective of this study was to determine the minimum quantities of phosphorus and potassium which must be applied with varying amounts of nitrogen in order to maintain maximum hay production and minimum level of insect infestation. This was more pronounced at the higher N rates and caused a significant N x K interaction during each of these years. There was no yield response to applied phosphorus at any N rate. Relation between levels of nitrogen and infestation percentage was positive but infestation rate decreased with the increase of potassium levels while there was no relation between levels of phosphorus …

An Overview Of The Physiology And Biochemistry Of N Reserves Mobilization In Forage Species, F Le Dily, A Ourry, J Boucaud

IGC Proceedings (1977-2023)

Recent works focusing on the physiological and biochemical events associated to perennial forages sustainability (re-growth after defoliation, winter survival), provided evidence that vegetative storage proteins (VSPs, ca proteins stored in remaining organs and specifically mobilized) were key organic compounds for shoot regrowth. Attempts to elucidate environmental conditions involved in VSPs deposit ability of different species are under progress today. In contrast, mechanisms of spring- or cut-induced proteolysis are investigated at a lesser extend. This contribution is an opportunity to summarize our knowledge of N-reserves mobilization and to set the question of VSPs breakdown regulation.

Intraspecific Competition In Lucerne And Relationships With Reserve Availability, Jean Christophe Avice, Alain Ourry, Gilles Lemaire, Jeffrey J. Volenec, Jean Boucaud

IGC Proceedings (1977-2023)

Below-ground reserves are thought to provide an indication of a forage potential for shoot regrowth after defoliation. The aim of this work was to re-evaluate the causal relationships existing between organic reserves (non-structural carbohydrates and N reserves) and shoot regrowth of alfalfa. The variations brought about by cultivar differences (cv Lodi or Europe), length of the previous regrowth period (30 or 45 d), or by intraspecific competition for light within a dense canopy, were studied. Field grown plants were harvested at weekly intervals, and separated as dominant, intermediate and suppressed plants. Shoot regrowth yield was determined and taproot were analyzed …

Seasonal Fluctuations Of Vegetative Storage Proteins And Starch Concentrations In Stolons Of Trifolium Repens L., V Bouchart, A Ourry, J C. Simon, J Boucaud

IGC Proceedings (1977-2023)

The seasonal pattern of nitrogen, starch and vegetative storage protein (VSP) concentrations was studied in the stolons of two Trifolium repens L. genotypes (cv Aran and Rivendel). Maximum concentrations of starch were found in summer months; its hydrolysis occurred in winter, at the time, where VSP and nitrogen were accumulated. The decrease of nitrogen and VSP concentrations occurred during spring, and an inverse relationship was found between VSP concentrations in stolons and mean temperatures. The causal implications of starch and VSP availability on spring regrowth potential are discussed in relation with regulatory mechanism inducing VSP synthesis.

Cynodon Dactylon Control In Conservation Tillage Systems, A Rios, J M. Sanz

IGC Proceedings (1977-2023)

Bermudagrass (Cynodon dactylon L. PERS.) is the most important weed in Uruguay. With the development of conservation tillage systems, chemical control of bermudagrass becomes essential. The objective of this research was to evaluate, in a long term integrated program, bermudagrass chemical control during the first year of a pasture. Application of glyphosate and no-tillage seeding of the pasture took place during fall. A 70% reduction of underground part of the weed was detected. The chemical control, together with a conservation tillage system and an adequate pasture management allowed an important reduction in bermudagrass level for the first year pasture. …

Legume Seedling Development In No Till Pasture Establishment, J L. Rossi, V A. Deregibus

IGC Proceedings (1977-2023)

The objective of this study was to compare no-till and conventional seeding of pasture and their effects on legume establishment. The presence of residue cover reduced legume seedling establishment and weed population under no-till seeding. The reduction in establishment was associated with the physical impediment of the residue cover and the decay of seedling vigor when passing through that cover.

Water Relations In Berseem Cultivars Under Drought Stress, A Iannucci, A Rascio, M Russo, P Martiniello

IGC Proceedings (1977-2023)

Berseem clover (Trifolium alexandrinum L.) is a crop of particular interest in semi-arid regions, used for herbage and hay productions. However, its seed yield is reduced by drought stress that occurs during seed filling. In this study five cultivars (Axi, Big Bee, Lilibeo, Sacromonte and Saniros) subjected to four irrigation frequencies in controlled environment, were compared for their physiological responses to subsequent water stress period (3 days). Some parameters (leaf water potential (), osmotic potential (þ), relative water content (RWC) and gravimetric soil water content (GSWC)) related to plant water status were recorded. Plants subjected to previous periods of …

Modelling The Effect Of A Variable Light Extinction Coefficient And Leaf Dispersion On Light Partitioning Between Species In A Grass-Clover Mixture, M Nassiri, A Elgersma

IGC Proceedings (1977-2023)

Light partitioning in a grass-clover mixture was studied using a general competition model. The model assumes a fixed extinction coefficient (k) and no leaf dispersion. This was compared with modelling the effect of different k of both species over height as well as the effect of type of leaf dispersion. These new assumptions led to a better estimation of the light partitioning between both species. For grass the effect of variable k and leaf dispersion was similar and in both cases the total absorbed light was lower than under default conditions. For clover the new assumptions led to a higher …

Ecotypic Adaptation Of Medicago Polymorpha Along A Gradient In Central Chile: Growth And Seed Production, A Del Pozo, C Ovalle, J Avendano

IGC Proceedings (1977-2023)

Relative growth rate, total dry weight and seed yield on 19 accessions of burr medic (Medicago polymorpha L.) from different bioclimatic conditions, were assessed at Cauquenes (35°58’;72°17’W) in the subhumid mediterranean region. The accessions were sown in microplots over raised beds during two years (1991 and 1992), and swards cut periodically at 2, 6 and 10 cm height. There were significant differences between accessions in both total dry weight and seed yield (P < 0.001, Table 1), but the interaction between accessions and height of cutting was not significant (P > 0.05). Total dry weight was positive correlated with days to flowering (r2 = 0.81; P > 0.01).

Effects Of Nitrogen On The Growth Of Hyparrhenia Diplandra, J Nkandza

IGC Proceedings (1977-2023)

The nitrogen effects on Hyparrhenia diplandra were studied. Plants were grown on nutrient solutions of variable concentrations in nitrogen. The supplied nitrogen increased tillering, leaf production, lamina area, total dry matter accumulation and total nitrogen accumulation in lamina. A detailed examination showed that the effect on tillering was the main cause of the differences observed in dry weights between different treatments. The nitrogen supply elongated significantly the lamina and nitrogen deficiency increased its thickness; but this was not enough to compensate the loss of weight in lower nitrogen treatment. The lamina area as well as nitrogen accumulation in the lamina …

Biochemical And Isoenzyme Analysis Of Seven Pennisetum Purpureum (Schum.) Cultivars, E E. Bach, V B.G. Alacantara, P B. Alcntara, E A. Veasey

IGC Proceedings (1977-2023)

This study characterized seven Pennisetum purpureum cultivars, namely cv. Anão, Bajra, Cameroon, Guaçu, Roxo, Taiwan A-144 and Uruckwami, through biochemical analysis, including protein, glucose and fructose contents, and polyacrylamide gel electrophoresis using the esterase system, by sampling 30, 60, 90, 120 and 150 dayold leaves. Cultivar Taiwan A-144 presented the highest number of nodes per stem and percentage of emerging buds. Protein concentration decreased gradually after 60 days for all cultivars, except for Anão. Cultivar Guaçu presented the highest level of glucose in 90 day old plants, whereas Cameroon presented the highest levels at 120 and 150 days. The esterase …

Effect Of Phosphorous Fertiliser On The Competition Between Two Tropical Grasses And Two Tropical Legumes, F D. Hu, R J. Jones

IGC Proceedings (1977-2023)

The effect of P fertiliser on the competition between grass and legume in four grass-legume mixtures : Urochloa mosambicensis cv. Nixon/ Stylosanthes hamata cv. Verano; Nixon/S.scabra cv. Seca; Bothriochloa pertusa cv. Bowen/Verano and Bowen/Seca were studied. Each mixture was grown in a low P, low N soil, in pots. A standard replacement series design with two P levels (0 and 10 kg/ ha equivalent) and 3 replicates were used. Seventy days after sowing, Nixon mixtures outyielded Bowen mixtures, and Verano mixtures outyielded Seca mixtures. P increased top and root yields of all mixtures but there was no significant (p …

Selection And Agronomic Characterization Of Leucaena Spp. Genotypes For Cold Tolerance. I. Dry Matter Yield., M C. Goldfarb, J F. Casco

IGC Proceedings (1977-2023)

Biotypes of Leucaena spp (56) were evaluated in order to identify those with tolerance to low temperature and with desirable characteristics as a forage crop. Selection was done at two phases. Phase I: 92 days old seedlings (n=2800) were subjected at two temperatures treatments during 14 hours: T1= -8 °C and T2= -3 °C. Selection criteria was established as 50% of live leaves remained after treatments were applied. Phase II: Plants that survived phase I were planted at field conditions and agronomic characteristics were measured. Seventeen plants were selected from eleven different biotypes, resulting one from T1 and the rest …

Effect Of Snowtrapping And Fertilization On Production Of Crested Wheatgrass And Native Pastures In Southwest Saskatchewan, M P. Schellenberg, J Waddington

IGC Proceedings (1977-2023)

The benefits of increasing soil water with snow management and fertilizer for annual and perennial crops have been demonstrated for semiarid environments. We examined the combined effect of snow management and fertilizer on forage production. In 1985, vertical wood slat or slotted plastic snow fencing (0.7m high) were erected on crested wheatgrass (Agropyron cristatum) pasture. In 1986, five rates of fertilizer: 400, 200, 100, 50, 0 kg ha-1 nitrogen each with 50 kg ha-1 phosphorous and a sixth treatment with no fertilizer were applied to each side and type of the snowfence. A second site was selected on …

Light Quality Effects On Grass Seedling Growth And Development, P G. Jefferson, R Muri

IGC Proceedings (1977-2023)

The poor establishment success of Russian wildrye (Psathyrostachys juncea Fisch. Nevski) limits its use. Our hypothesis was that Russian wildrye (RWR) was more sensitive to light competition than crested wheatgrass (Agropyron desertorum Fischer ex Link) or Dahurian wildrye (Elymus dahuricus Turcz. Ex Grieseb.). Seedlings were grown under plastic filters that altered both quantity and quality of light. Tiller counts, leaf counts, leaf area, light intensity and red:farred light ratio (above and beside each seedling) were recorded each week for four weeks after planting. Seedling dry weights were determined at four weeks. Low light intensity significantly reduced tiller …

Morphogenesis And Growth Analysis Of Panicum Maximum Cultivars, A Gomide, C A.M Gomide

IGC Proceedings (1977-2023)

Four cultivars of Panicum maximum, grown in pots, were evaluated regarding their leaf appearance and elongation rates, tillering appearance rate, as well as growth indices. Differences among cultivars were found as to leaf appearance and elongation rates and tillering rates. Main tiller leaf appearance was higher relative to primary tiller in the seedling growth, only. Primary tiller showed higher leaf elongation rate in the aftermath growth. No difference among cultivars was found for drymatter yield after 52 d growth period, leaf mortality, net assimilation rate, leaf area ratio and relative growth rate.

Competitive Interactions Between Palatable And Unpalatable Grasses: Effects Of Selective Defoliations Of The Palatable Grasses, R A. Distel, A S. Moretto

IGC Proceedings (1977-2023)

Selective herbivory of the palatable species appears to be a dominant mechanisms contributing to species competitive replacement in grasslands. Selective herbivory of the palatable species allows unpalatable species to realize a competitive advantage within the community. To test this hypothesis we compare the competitive ability of the unpalatable grasses Stipa trichotoma or S. gyneriodes in the presence of nondefoliated and defoliated plants of the palatable grass S. clarazii. The three species are native to a temperate semiarid grassland of Argentina. The response variables estimated in S.trichotoma and S.gynerioides, at both plant and tiller levels, were higher (P < 0.05) in the presence of defoliated than in the presence of undefoliated plants of S.clarazii. These results support the hypothesis that selective herbivory of the palatable species confers unpalatable species a competitive advantages, contributing to species competitive replacement within the community.

Allelopathic Interactions Among Forage Grasses And Legumes, A P.S Souza Filho, T De J.D. Rodrigues, L.R. De A. Rodrigues, R A. Reis

IGC Proceedings (1977-2023)

Aqueous extracts at 10% were prepared with the shoots of the grasses Brachiaria brizantha cv. Marandú, B. decumbens, B. humidicola, and of the legumes Calopogonium mucunoides, Leucaena leucocephala, Stylosanthes guianensis cv. Mineirão. The effects of the extracts were evaluated on the germination and on the radicleelongation of the forages. The pH, the electric conductivity and the osmotic potential of the extracts were determined. The germination and radicle biossays were conducted in germination chambers, with controlled temperature and photoperiod. The pH and the presence of ions did not contribute to the effects observed. The extracts of the legumes tended …

Early Ontogenetic Responses Of Six Commercial Chloris Gayana Cultivars To Salinity, E Taleisnik, H Perez, G Peyrano, C Arias

IGC Proceedings (1977-2023)

Some physiological aspects relevant to pasture establishment under saline conditions were evaluated in six cultivars of Chloris gayana . Two tetraploid cultivars: Boma and Callide, and four diploid ones: Bell, Katambora, Pioneer and a local accession of Pioneer, were analyzed. The effect of salinity on seedling emergence, the number of stolons per plant and frost tolerance were evaluated in the field, while effects on germination, early vegetative growth, regrowth after clipping, ion accumulation and stolon rooting were assessed in the greenhouse. Salinity had a negative effect on seedling emergence. Saline solutions delayed or altogether inhibited germination, but seeds retained viability …

Interpreting Indicators Of A Transfer Of N From Legume To Grass In Competition Studies, P G. Tow

IGC Proceedings (1977-2023)

The transfer of N from legume to grass in mixtures is important for regulating competition. In competition studies which include both monocultures and mixtures, N transfer should be detectable by grass N measurements but may be masked by competitive reductions in grass growth. In the study reported here, whole plant DM and N were measured in Panicum maximum var trichoglume and Neonotonia wightii grown in monocultures and additively in mixtures. While competition reduced whole grass plant DM and N in mixture relative to monoculture, higher grass shoot % N and N yield in the mixture at early harvests appeared reliable …

A Comparison Of Production And Soils In Modified Mixed Prairie Community, S W. Porter, W D. Willms, J F. Dormaar, B H. Ellert, H H. Janzen

IGC Proceedings (1977-2023)

This study examined the effects of reseeding a Stipa-Agropyron- Bouteloua community to monocultures of crested wheatgrass (Agropyron cristatum (L.) Geartn.), Russian wild rye grass (Elymus junceus Fisch.), and wheat (Triticum aestivum L.) on above and below ground biomass and indicators of soil quality. Summer fallowed wheat produced 10817 kg ha-1 and 4090 kg ha-1 of above ground below ground biomass respectively whereas the native community produced 3191 kg ha-1 above ground and 13013 kg ha-1 of below ground biomass. However wheat, crested wheatgrass and Russian wildrye grass generally showed a lower biological index, phosphatase and dehydrogenase activity.

Nitrogen Use Efficiency Of Timothy Populations, G Belanger, C Murray, R Michaud, F Gastal, J E. Richards

IGC Proceedings (1977-2023)

The objective of this study was to determine the variability in N use efficiency among field-grown timothy (Phelum pratense L.) populations. Shoot biomass and N uptake were measured at the end of the spring growth cycle on six timothy populations fertilized with three N rates at two sites in Eastern Canada. The variability in shoot biomass among populations was similar under limiting and nonlimiting N conditions. The ranking of the populations, however, differed under limiting and non-limiting N conditions, and also between the two sites under limiting N conditions. The differences in shoot biomass among populations under highly N …

Characterization Of The Leaf Anatomy Of Panicum Virgatum Germplasm, D S. Fisher, J C. Burns, J P. Pienaar

IGC Proceedings (1977-2023)

Both the yield and digestibility of C4 grasses have been related to anatomical characteristics. The objectives of the current work were to test switchgrass with varied yield and digestibility for variation in anatomical measurements and to develop a method of graphically representing the anatomy. Six accessions were established in replicated field plots and the lamina were sampled, dehydrated and embedded for anatomical study. Midrib dimensions were excluded from study but perimeters of primary and secondary vascular bundles in the lamina were measured. Lamina thickness was determined at the primary bundle, secondary bundle and at the minimum between the bundles. The …