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Full-Text Articles in Entire DC Network
The Function Of Grasslands In The Concentrated And Specialized Agriculture And In The Management Of Landscape, Blazej Krcmar
The Function Of Grasslands In The Concentrated And Specialized Agriculture And In The Management Of Landscape, Blazej Krcmar
IGC Proceedings (1977-2023)
Concentration and specialization of the largescale agricultural production have come to the focus in recent years and, due to this fact, a new type of landscape is being formed. It is now of topical value to keep a given level of ecosystems heterogeneity. This is essential both in making the production more intensive and in conserving the necessary equilibrium of nature. A slight reduction of natural ecosystems, especially of grassland swards, by the so-called intensification of agroecosystems might bring about an undesired ecological crisis of landscape. To prevent this danger is our task.
Studies On The Alteration Of Grassland Ecosystems Under Intensification Of Grassland Management In The Gdr, Rudolf Hundt
Studies On The Alteration Of Grassland Ecosystems Under Intensification Of Grassland Management In The Gdr, Rudolf Hundt
IGC Proceedings (1977-2023)
The objective of the investigations described in this paper consisted in finding out the effect of industry-like production methods on grassland ecosystems from the plant-sociological, ecological, and agricultural points of view. In 1954, grassland phytocoenoses in the Elbe river valley near Dessau and in the Mulde river valley near Wurzen had been the object of geobotanical investigations. These investigations were repeated in 1976. Sprinkler irrigation, intensive eutrophication, and ihe inclusion of grazing resulted in a complete change of the ecosystems. The productiveness of the swards improved substantially both in quantitative and in qualitative respect, and the number of species declined …
Persistence Of Various Grassland Components Under Varying Compaction Of The Sward, Vladimir Regal, Miloslava Vesela
Persistence Of Various Grassland Components Under Varying Compaction Of The Sward, Vladimir Regal, Miloslava Vesela
IGC Proceedings (1977-2023)
Studies on poaching-reistant successors on 32 types of plant stands and the evaluation of 210 stands on test runs helped to select the species of highest resistance to poaching. By means drawn of such regarding studies the conclusions composition have of grassbeen sports mixtures for grounds, stress-resistant playgrounds, swards airfields, (pastures,and others). position, Poa These Lolium pratensis mixtures perenne bemay be ingthe of simple predominant com of species. Tr(folium repens may and serve for short-growing supplementingspecies the stand. In mountainous, Festuca more rubra humid lo cations Agrostis with tenuis poorer proved soils, suitable for supplemenand tation.
Wildfires 1n Semiarid Artemisia/ Stipa Grasslands, James A. Young, Raymond A. Evans
Wildfires 1n Semiarid Artemisia/ Stipa Grasslands, James A. Young, Raymond A. Evans
IGC Proceedings (1977-2023)
We investigated plant succession after accidental burning of Artemisia/ Stipa grasslands. Burning is the most important catastrophic stand renewal process for this grazing resource. The most striking impact of burning was the complete removal of the dominant shrub Artemisia tridentata Nutt. which does not sprout after removal of the aerial portion of the plant. Numerous other species of shrubs do rootsprout after burning and assume dominance of the plant community for 10 to 15 years. The native perennial grasses were not unduly injured by the fire, but the density of perennial grass had been greatly reduced by a century of …
The Evaluation Of Relationships Between Ecological Factors And Production On Permanent Grassland, Vladimir Krajovic
The Evaluation Of Relationships Between Ecological Factors And Production On Permanent Grassland, Vladimir Krajovic
IGC Proceedings (1977-2023)
On 42 sites in 10 districts of the Carpathian region of the CSSR, relationships were examined between grassland production and regional, climatic (precipitation, temperature, solar radiation), and soil conditions (soil type, pH, S, 'r, V, C0., nutrients, and clay fraction). To this, five variants of fertilization were used (0; PK; 120 kg N/ha + PK, 240 kg N/ha + PK; 480 kg N/ha + PK). None of the natural ecofactors is generally characteristic enough for determining an optimal production. But the nutrition and the utilization of grass stands are important under each condition. Therefore, a system of differentiated grassland management …
The Yield Dependence Of Grass/Clover Mixtures On Different Environmental Conditions, Zygmunt Gryncewicz, Franciszek Gospodarczyk
The Yield Dependence Of Grass/Clover Mixtures On Different Environmental Conditions, Zygmunt Gryncewicz, Franciszek Gospodarczyk
IGC Proceedings (1977-2023)
Red clover as pure crop as well as in mixture with grasses gave the best yields in foothill locations (450 m above sea level) above all under conditions of sufficient precipitation. In mountain locations (850 m above sea level) grasses showed better growth, accounting for the main part in the overall herbage crop. In the mixtures compared, meadow fescue proved to be the best component in all altitudes, Italian ryegrass was best in lowland areas, and timothy in the highest altitudes. Best yields in terms of oat equivalents were obtained from mixtures consisting of 75% clover and 25 % grasses. …
Flood Adaptation And Productivity Of Savanna Grasses, E Gonzalez Jimenez, A Escobar
Flood Adaptation And Productivity Of Savanna Grasses, E Gonzalez Jimenez, A Escobar
IGC Proceedings (1977-2023)
Savannas subjected to seasonal flooding occupy· vast areas of the Tropics. Above-ground biomass values for Venezuelan flooded savannas are high and related to the longer availability of water. C3 plants colonized the waterlogged unit and showed the highest productivity and nutritive value. This natural system permits a prolonged grazing season. These first results show the great potential for animal production of this ecosystem, stressing the need for coordinated research efforts in order to gain a better understanding of it.
Studies On Site, Vegetation And Intensification Of Temporarily Flooded Grassland Of The Lower Oder River Near Schwedt, Gisbert Schalitz
Studies On Site, Vegetation And Intensification Of Temporarily Flooded Grassland Of The Lower Oder River Near Schwedt, Gisbert Schalitz
IGC Proceedings (1977-2023)
On the temporarily flooded grassland of the lower Oder River near Schwedt, yields can be considerably increased by establishing highyielding Phalaris arundinacea stands. In the drier zone it is indispensable to kill the old sward. To this effect, adequate methods should be chosen according to the type of existing vegetation. In the range of moisture-tolerant plant associations, increased nitrogen fertilization will allow to build up high-yielding pure stands in short time.
Lead Content In Meadow Vegetation From NonContaminated Areas, Andrzej Sapek
Lead Content In Meadow Vegetation From NonContaminated Areas, Andrzej Sapek
IGC Proceedings (1977-2023)
In 270 samples of selected meadow plant species, taken from natural sites and permanent meadows in the 1st-cut period, the lead content was determined. Mean lead content in particular species fluctuated from 0.36 ppm in Phalaris arundinacea to 1.38 ppm in Carex vulpina. On a whole, the lead content was lower in grasses than in herbs. No relationship between the total lead content in soil and plants has been proved. On the other hand, a positive and often significant relationship between the lead content in particular plant species and their potassium, copper, nickel, and phosphorus contents was observed.
Influence Of Plant Nutrition And Method Of Utilization On The Accumulation And Decomposition Of Root Matter In Meadow Soils, Yan Liyv, Rikhard Toomre
Influence Of Plant Nutrition And Method Of Utilization On The Accumulation And Decomposition Of Root Matter In Meadow Soils, Yan Liyv, Rikhard Toomre
IGC Proceedings (1977-2023)
Root matter formation of forage plants depends primarily on soil fertility. In fertile soils and under intensive fertilization less root matter is formed than in soils of low fertility. The decomposition of root matter as influenced by microbiological processes was found to be more intensive under grazing than under mowing. The application of high rates of nitrogen fertilizer (more than 200 kg N/ha) over longer periods is likely to cause undesirable changes in the relationship between forage plants and soil microorganisms, this resulting in yield decline and in lower efficiency of the fertilizers applied.
The Influence Of Grassland Plants Ort The Accu1nulation Of Humus And Nitrogen In The Soil In The Conditions Of The Estonian Ssr, Arnold Sau
IGC Proceedings (1977-2023)
The accumulation of nitrogen and humus in soil under perennial grassland plants was studied between 1965 and 1974 in a trial laid out on carbonated reddish brown sandy loam moraine of original levels of 0.22 % humus and 18 m %1 nitrogen, the C: N ratio being 7 .2. Nitrogen and humus accumulation in the moraine was found to proceed the faster, the higher were the yields of above-ground and underground plant matter. In the course of 10 years, the humus content in the upper 5 cm of soil reached 1.92 to 2.26 % for the higheryielding variants (grasses+ 150 …
Nitrogen Status Of A Shortgrass Prairie, Pasture Ecosystem, Robert G. Woodmansee, Jerrold L. Dodd, Rudolph A. Bowman, Charles E. Dickinson
Nitrogen Status Of A Shortgrass Prairie, Pasture Ecosystem, Robert G. Woodmansee, Jerrold L. Dodd, Rudolph A. Bowman, Charles E. Dickinson
IGC Proceedings (1977-2023)
Nitrogen was partitioned among soil organic matter, living and dead plant material, microorganisms, above-ground and below-ground animals, and mineral N in a shortgrass prairie, pasture ecosystem in eastern Colorado, USA Soil organic matter contained the largest amount of N (89.5 %), and dead plant material contained 6.8 % of the total N in the system. Living organisms contained 3.4 % of the N in the ecosystem. Mineral N accounted for 0.2 %. Less than 1.0 % of the N in the system was located above ground. The amount of N immobilized in animals was small.
Nutrient Leaching In Hydromorphic Grassland Soils As Established In Lysimeters, Gerhart Mundel
Nutrient Leaching In Hydromorphic Grassland Soils As Established In Lysimeters, Gerhart Mundel
IGC Proceedings (1977-2023)
Lysimeter experiments were laid out for studying the leaching of nitrogen, calcium, potassium, and phosphorus from different hydromorphic soils. Most of the hydromorphic soils, above all those of low-bog sites, have to be considered as instable open systems from the very beginning of their cultivation. Matter removal well exceeds the amount of matter introduced into these soils. The degree of nutrient leaching in most cases is clearly dependent on the soil humus status. Attention is drawn to the intensive calcium leaching and the low level of nitrogen removal as compared with anpydromorphic soils. The level of potassium leaching is closely …
Available Soil Nutrients Related To Species Composition Of Some Meadow Communities In North-Western Bohemia, Emilie Balatova-Tulackova
Available Soil Nutrients Related To Species Composition Of Some Meadow Communities In North-Western Bohemia, Emilie Balatova-Tulackova
IGC Proceedings (1977-2023)
The pH value as well as the content of humus and some available nutrients (Ca, Mg, K, P, N) were assessed in soil samples taken from the upper part of the rhizosphere in 15 different types of moist meadows situated in northwestern Bohemia. The results obtained were evaluated mainly from the point of view of the occurrence of Ca, K, and Pin soil related to the species composition (which is the decisive factor in its classification in the phytocenological system). The greatest indicative value is shown by plants with relatively narrow ecological amplitude in the given phytocenological bounds, such as …
Yearly Nitrogen Budget In Natural And Fertilized Grasslands Of A Bohemian-Moravian Highlands District, Milada Findeisova, Vladimir Ruzicka, Blanka Ulehlova
Yearly Nitrogen Budget In Natural And Fertilized Grasslands Of A Bohemian-Moravian Highlands District, Milada Findeisova, Vladimir Ruzicka, Blanka Ulehlova
IGC Proceedings (1977-2023)
Simplified models are presented of nitrogen cycling in the three grassland ecosystems, as compiled from soil, plant, rain- and lysimetric water analyses pertaining to an experimental site near Kamenicky, in the nature conservancy area Zdarske vrchy in the Bohemian-Moravian highlands. The plant stands, all originally classified as Polygalo-Nardetum strictae, include a control and two stands as modified by two levels of fertilization for three years. The increment of nitrogen harvested decreases considerably at the higher level of fertilization, while the nitrogen losses from the ecosystem increase and the atmospheric nitrogen fixation decreases dramatically.
Mineral Composition Of Vegetation Related To Primary Production In Alluvial Meadow Ecosystems, Jana Jakrlova
Mineral Composition Of Vegetation Related To Primary Production In Alluvial Meadow Ecosystems, Jana Jakrlova
IGC Proceedings (1977-2023)
Concentration and ratio of mineral nutrients, dynamics of mineral nutrient uptake per 1 m2, and the contents of mineral nutrients in permanent biomass reserve and in maximum biomass were assessed in three selected types of meadow ecosystems representing a natural hydrological series in a given area (dry, moist, wet). The assessment was based on chemical analyses (N, P, K, Na, Ca, Mg) and production analysis of above-ground and underground parts of defined vegetation.
Total above-ground biomass produced per year was estimated (from the dry type to the wet one) at 706, 1070, 2430 g • W • m-2, respectively; total …
Biomass Budget And Energy Flow In Alluvial Meadow Ecosystem, Milena Rychnovska, Blanka Ulehlova, Jana Jakrlova, Marta Tesrova
Biomass Budget And Energy Flow In Alluvial Meadow Ecosystem, Milena Rychnovska, Blanka Ulehlova, Jana Jakrlova, Marta Tesrova
IGC Proceedings (1977-2023)
Primary production, production processes, and decomposition have been studied in alluvial meadow ecosystems for 6 years. Water has been found to be the decisive factor in the energy flow and mineral elements turnover. The quality and quantity of production and decomposition processes depend on the occurrence and duration o( floods. Permanent pool of underground biomass in Alopecurus pratensis stand makes 45.3 %, permanent pool of shoot biomass makes 54.7 % of the total biomass. 19.4 % of the total biomass is taken off as forage. 11. 7 % of shoot biomass is decomposed during the summer season, and 3 .1 …
Current Aspects Of Eco-Physiological Studies Of Meadow Plants, Momcilo Konic
Current Aspects Of Eco-Physiological Studies Of Meadow Plants, Momcilo Konic
IGC Proceedings (1977-2023)
Basic parameters applied in eco-physiological studies of meadow plants are: water balance (hydration, transpiration intensity, amounts and forms of water, water deficit, etc.), assimilation balance (CO2 balance, assimilation performance, compensation effect), matter production. Eco-physiological studies should be followed by microclimatic measurements and the anatomical analysis of the meadow plants under study. Eco-physiological studies of meadow plants, if performed in a complex and systematic way, constitute the safest basis for detennining the characters of the entire meadow plant community under the concrete conditions of natural factors prevailing in terms of natural conditions and human influence.
Landscape Management Problems Of Grassland Utilization In Mountainous Regions Of The Gdr, Peter Hentschel
Landscape Management Problems Of Grassland Utilization In Mountainous Regions Of The Gdr, Peter Hentschel
IGC Proceedings (1977-2023)
In the medium-altitude mountains of the GDR, many meadows cannot be utilized for intensive forage production. Because of their importance for recreation, game feeding and nature conservation, general afforestation is not possible. A model is presented that allows for every meadow to choose between intensive utilization, afforestation, and reservation for other social needs. Management methods for meadows not suitable for intensive utilization, especially the employment of herbicides, are discussed.
Oregon State Rank Assessment For Bensonia (Bensoniella Oregana), Nora Dunkirk, Sue Vrilakas, Gabriel Campbell
Oregon State Rank Assessment For Bensonia (Bensoniella Oregana), Nora Dunkirk, Sue Vrilakas, Gabriel Campbell
Institute for Natural Resources Publications
Oregon state conservation status assessment for Bensonia (Bensoniella oregana) using NatureServe methodology, 2026.
Coherent Two-Photon Backscattering And Induced Angular Quantum Correlations In Multiple-Scattered Two-Photon States Of The Light, Nooshin M. Estakhri, Theodore B. Norris
Coherent Two-Photon Backscattering And Induced Angular Quantum Correlations In Multiple-Scattered Two-Photon States Of The Light, Nooshin M. Estakhri, Theodore B. Norris
Engineering Faculty Articles and Research
We present the emergence of coherent two-photon backscattering, a manifestation of weak localization, in multiple scattering of maximally entangled pure and fully mixed two-photon states and examine the effect of entanglement and classical correlations. Quantum correlations in backscattering are investigated for finite three-dimensional disordered structures in the weak localization regime, as well as systems of a small number of scatterers with specified spatial arrangements. No assumptions are made about the statistical behavior of the scattering matrix elements. Furthermore, we study the interplay between quantum correlations induced by multiple scattering and the correlations that may be present in the illumination fields, …
Cooperative Evolution For Discovering Scalable Spiking Neural Network Architectures, Catherine C. Rodriquez
Cooperative Evolution For Discovering Scalable Spiking Neural Network Architectures, Catherine C. Rodriquez
LSU Master's Theses
SNNs are a foundational model in neuromorphic computing, where efficient architectures must be discovered for a wide range of applications. Evolutionary methods, such as EONS, offer a flexible approach to this search but become increasingly difficult to scale as task complexity grows due to the rapidly expanding combined topology–parameter search space and associated memory demands. To address this challenge, we propose a co-evolutionary ensemble framework in which a population of candidate SNNs is evolved with fitness defined by each network’s marginal contribution to group performance. Grounded in cooperative game theory and difference evaluation functions from multiagent systems, this formulation provides …
Mental Health Self-Perceptions And Resource Utilization In Undergraduate Students At Binghamton University, Nicole J. Dreznin, Sarah Marcus
Mental Health Self-Perceptions And Resource Utilization In Undergraduate Students At Binghamton University, Nicole J. Dreznin, Sarah Marcus
Binghamton University Undergraduate Journal
Undergraduate students face increasing rates of mental health challenges, however discrepancies in mental health literacy and utilization of resources may exist across student populations. This study examined the perceptions of mental health in undergraduate students at Binghamton University and if they differed among STEM vs non-STEM, man vs. women, and first-generation vs. continuing generation undergraduate students. A 20-question survey, containing 5 demographic questions and 15 mental health related questions was distributed through Qualtrics to 9 undergraduate classes. The available response choices were based on the Likert scale. A total of 1266 students participated. Chi square tests of independence were done …
Real-Time Image Denoising And Reconstruction Using Generative Adversarial Networks (Gans), Roa'a M. Al_Airaji, Haider Th. Salim Alrikabi, Rula Kamil, Svyd Iryna
Real-Time Image Denoising And Reconstruction Using Generative Adversarial Networks (Gans), Roa'a M. Al_Airaji, Haider Th. Salim Alrikabi, Rula Kamil, Svyd Iryna
Karbala International Journal of Modern Science
This paper presents a real-time image denoising and reconstruction system based on a compact Generative Adversarial Network (GAN) designed for embedded systems and edge computing. The proposed model employs a [ generator and a PatchGAN discriminator, trained using hybrid loss function that combines L1, perceptual, and adversarial terms to balance pixel and perceptual realism. Evaluations were conducted on multiple datasets, including DIV2K, BSD68, SIDD, DND, RENOIR, and PolyU at noise levels (σ = 15, 25, 50). Quantitatively, the proposed model achieves an average PSNR of 32.8 dB and an SSIM of 0.88, which is higher by more than 3 dB …
Synergistic Effects Of Arbuscular Mycorrhizal Fungi And Foliar Nitrogen–Phosphorus Application On Maize Productivity Under Irrigated And Rainfed Conditions, Mst. Lailatul Ferdows, Saima Biswas, Mizanur Rahman, F. M.Jamil Uddin, Md. Nayan, Aporna Tabassum Api, Mohaiminul Islam, Nadia Islam, Swapan Kumar Paul, Md. Harun Rashid
Synergistic Effects Of Arbuscular Mycorrhizal Fungi And Foliar Nitrogen–Phosphorus Application On Maize Productivity Under Irrigated And Rainfed Conditions, Mst. Lailatul Ferdows, Saima Biswas, Mizanur Rahman, F. M.Jamil Uddin, Md. Nayan, Aporna Tabassum Api, Mohaiminul Islam, Nadia Islam, Swapan Kumar Paul, Md. Harun Rashid
School of Earth, Environmental, & Marine Sciences Faculty Publications
A field experiment was conducted at the Agronomy Field Laboratory of Bangladesh Agricultural University to evaluate the effects of arbuscular mycorrhizal fungi (AMF) inoculation and foliar supplementation of nitrogen (N) and phosphorus (P) on the performance of maize (Zea mays L.) under irrigated and rainfed conditions. The experiment followed a randomised complete block design with two levels of AMF (inoculated and non-inoculated) and four foliar treatments (no N and P, N only, P only, and combined N + P). The recommended dose of fertiliser (RDF) was applied as a soil application to all treatments. AMF inoculation significantly increased grain yield …
Development And Evaluation Of A Community-Based Water Quality Monitoring Program In Mississippi, Beth H. Baker, Lily Langstaff, Mona Dominguez, Sergio Ruiz-Cordova, Eric Sparks, Madison Gnoose
Development And Evaluation Of A Community-Based Water Quality Monitoring Program In Mississippi, Beth H. Baker, Lily Langstaff, Mona Dominguez, Sergio Ruiz-Cordova, Eric Sparks, Madison Gnoose
Journal of Extension
Community-based water monitoring (CBWM) programs provide mechanisms for education and water quality data collection. In this pilot program, we adapted a long-standing CBWM program from Alabama to Mississippi. We assessed the efficacy of the initial program implementation in promoting changes in knowledge, skills, and behavior of participants. Results indicated that 94% of survey respondents reported increased knowledge, 96% reported learning a new skill, and 99% reported an intention to start monitoring, but only 33% engaged in active monitoring. This evaluation summary offers data-driven strategies to expand and adopt CBWM into Extension curricula that build knowledge, skills, and capacity for community …
A Categorical Framework For Modeling Genetic Drift, Taylor G. Mendes
A Categorical Framework For Modeling Genetic Drift, Taylor G. Mendes
Rose-Hulman Undergraduate Mathematics Journal
Genetic drift describes changes in allele frequencies that arise from chance sampling in finite populations. This paper develops a categorical framework for organizing the structural features of drift. Population states are modeled as objects, evolutionary transitions as morphisms, reversible transitions as groupoid morphisms, and structure-preserving comparisons between models as functors. Group actions are used to describe deterministic evolutionary operators such as mutation and selection, while orbits and fixed points identify reachable allele-frequency states and stable absorbing outcomes. Universal properties are then used to describe drift as a coherence condition connecting stochastic transitions with deterministic evolutionary maps. The resulting framework complements …
Warm-Air And Forced-Air Ventilation Drying Of Grass Seeds, Werner Maltry
Warm-Air And Forced-Air Ventilation Drying Of Grass Seeds, Werner Maltry
IGC Proceedings (1977-2023)
For the design of warm-air conveyor driers and of ventilated bins to be used for grass seeds drying, certain parameters of the drying characteristics under varying conditions must be known. Investigations in a climatized chamber with seeds from different plant species at varying bulk height, inlet air temperature, and rate of air flow have shown the drying characteristics of a layer to be quite similar to those of a single drying crop. The curve of the drying velocity can be approximated by two branches, a first branch with constant drying velocity and a second straight-lined declining branch. The whole operation …
Problems Of Phytophagous And Pollinating Insect Control Of Seed Lucerne In France, Rene Bournoville, Pierre Guy, Jean-Noel Tasei, Alain Delaude F.N.A.M.S
Problems Of Phytophagous And Pollinating Insect Control Of Seed Lucerne In France, Rene Bournoville, Pierre Guy, Jean-Noel Tasei, Alain Delaude F.N.A.M.S
IGC Proceedings (1977-2023)
This paper is concerned with two factors of lucerne seed yields: phytophagous and pollinator insects. There are three groups of phytophagous insects, i.e. foliage species: Acyrthosiphon pisum, Apion pisi, Hypera variabilis, Colaspidema atrum; gall midges: Dasyneura ignorata, Contarinia medicaginis; and seed pests: Laspeyresia medicaginis, Tychius aureolus, Adelphocoris lineolatus, Lygus rugulipennis, Bruchophagus roddi. Net sweeping, yellow dish trapping, and gall rearing were used for population and flight observation. Laboratory tests were carried out to determine the susceptibility of Miridae bugs, predators, and pollinators to insecticides. The possibility of rearing and multiplying Megachile pacifica was demonstrated. Studies on its local enemies and …
Progress In Grass Seed Production Through Specialization And Concentration, Heinz Hartmann
Progress In Grass Seed Production Through Specialization And Concentration, Heinz Hartmann
IGC Proceedings (1977-2023)
Specialization and concentration •in grass seed production require a long-term development programme. Such development programme has to be put into effect planfully and from year to year by all partners involved. The crews in charge of actual production must be in command of up-to-date seed-growing technologies and see with great continuity to their own further education. Both the farms and nationally-owned enterprises for seed and planting stocks (VEB Saatund Pflanzgut) must be furnished with efficient machinery and other facilities for adequate collection, treatment, and marketing of grass seed. A complex quality-ensuring system has to be established for high-accuracy control and …