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Articles 4381 - 4410 of 59512

Full-Text Articles in Earth Sciences

Alternative Stones And Cleaning Efficiencies For Historical Building Stones Used In İstanbul (Türkiye), Ömer Ündül, Tuğçe Erözmen, Namik Aysal, Ahmet Güleç Mar 2025

Alternative Stones And Cleaning Efficiencies For Historical Building Stones Used In İstanbul (Türkiye), Ömer Ündül, Tuğçe Erözmen, Namik Aysal, Ahmet Güleç

Turkish Journal of Earth Sciences

Historical buildings are important part of the common heritage of mankind. İstanbul comprises many historical buildings built by geo-materials. A limestone (named as Küfeki stone in the region) is one of the most widely used stone in and around the city since thousands of years. The durability, excavability and workability of the stone attract the usage of this stone. Besides the outcrops of the rock were very common. Unfortunately, nowadays quarries and outcrops of Küfeki stone are totally abandoned due to dense settlement. For this reason, replacement of damaged or polluted stone with the original stone is a hard task …

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Postseismic Groundwater Quality Investigation In Aquifers Following Earthquake-Induced Demolition Wastes: Hatay (Türkiye) Case Study, Pinar Avci, Gali̇p Yüce Mar 2025

Postseismic Groundwater Quality Investigation In Aquifers Following Earthquake-Induced Demolition Wastes: Hatay (Türkiye) Case Study, Pinar Avci, Gali̇p Yüce

Turkish Journal of Earth Sciences

The February 6, 2023 seismic sequence that hit, the Antakya district of Hatay (Türkiye), killed more than 50,000 people and caused extensive structural damages, resulting in the collapse of 80% of the building stock that generated over 100 million tons of debris. Understanding the impact of seismic events on water resources is highly important for ensuring human and environmental health. Herewith, a study was carried out over the Hatay area to assess the post-earthquake sustainable usability of groundwater for drinking, domestic, and irrigation purposes. 17 water points were investigated in September 2023, encompassing alluvial deposits with relatively high hydraulic conductivity …

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A New Fossil Woody Flora Of The Late Oligocene-Early Miocene Of Northwest İstanbul With A New Species, Ünal Akkemi̇k, Burcu Üner Mar 2025

A New Fossil Woody Flora Of The Late Oligocene-Early Miocene Of Northwest İstanbul With A New Species, Ünal Akkemi̇k, Burcu Üner

Turkish Journal of Earth Sciences

The silicified wood samples identified in Kabakça (Çatalca) and its surroundings have been found in the west of İstanbul Province. They come from terrestrial clastic sediments of the Late Oligocene-Early Miocene İstanbul Formation. Six silicified wood samples were collected and sectioned in transverse, tangential, and radial planes. As a result, five angiosperm taxa were identified. Three out of six fossil wood samples belong to Lauraceae (Cryptocaryoxylon istanbulensis Akkemik and Üner sp. nov., Lau-rinoxylon ehrendorferi Berger, 1953), and the others to Fabaceae (Dichrostachyoxylon zirkelii (Felix) Müller-Stoll and Mädel 1967), Ulmaceae (Zelkovoxylon crystalliferum Akkemik 2021), and Fagaceae (Quercoxylon mixtum Petrescu 1978). This …

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Facies And Depositional Architecture Of Upper Miocene Tidal Flat Sedimentation In Kefalonia And Corfu Islands, West Greece, Nicolina Bourli, Chrysanthos Botziolis, Penelope Papadopoulou, Panagiotis Zelilidis, Elena Zoumpouli, George Iliopoulos, Angelos G. Maravelis, Efthymios Trypsanas, Ioannis Oikonomopoulos, Aristotelis Pagoulatos, Avraam Zelilidis Mar 2025

Facies And Depositional Architecture Of Upper Miocene Tidal Flat Sedimentation In Kefalonia And Corfu Islands, West Greece, Nicolina Bourli, Chrysanthos Botziolis, Penelope Papadopoulou, Panagiotis Zelilidis, Elena Zoumpouli, George Iliopoulos, Angelos G. Maravelis, Efthymios Trypsanas, Ioannis Oikonomopoulos, Aristotelis Pagoulatos, Avraam Zelilidis

Turkish Journal of Earth Sciences

This research involves the integrated sedimentological and paleontological analysis of the Neogene tidal deposits in the eastern parts of the Hellenic Fold and Thrust Belt, in South Kefalonia (Paliolinos-Avithos coast) and in NW Corfu (Arillas coast) islands. The study of tidal is supported by illustrative outcrop photographs, with a particular emphasis on two synthetic outcrops. Sedimentary logs were generated to document detailed bed-by-bed measurements, descriptions, and identification of sedimentary structures. Additionally, over 75 samples were chosen for age determination and paleoenvironmental analysis. Micropaleontological analysis encompassed 52 samples from South Kefalonia and 23 samples from NW Corfu and the results point …

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Northeast Anatolian Obsidians: Preliminary Results, Tülay Bak, Ufuk Celal Yağcioğlu, Cüneyt Şen, Fatma Şi̇şman Tükel Mar 2025

Northeast Anatolian Obsidians: Preliminary Results, Tülay Bak, Ufuk Celal Yağcioğlu, Cüneyt Şen, Fatma Şi̇şman Tükel

Turkish Journal of Earth Sciences

Obsidian, whose physical properties are suitable for making cutting tools, was one of the most basic commodities traded in prehistoric times. Obsidian, not found everywhere and with its unique chemical composition, is often used to create maps of prehistoric migration and trade routes. There are many important obsidian sources in Anatolia. These sources were utilised in the prehistoric period. One of the most important challenges facing archaeologists is identifying the source area of the raw materials used to create obsidian stone tools in prehistoric settlements. The geochemical properties of the obsidian from Northeastern Anatolia are less well known than those …

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Designing A Cave Air Monitoring System: Guide And Feedback From 15 Years Of Monitoring The Cussac Cave (France), Nicolas Peyraube, Jessica D. Villanueva, Fabien Naessens, Roland Lastennet, Sylvain Mateo, Alain Denis Mar 2025

Designing A Cave Air Monitoring System: Guide And Feedback From 15 Years Of Monitoring The Cussac Cave (France), Nicolas Peyraube, Jessica D. Villanueva, Fabien Naessens, Roland Lastennet, Sylvain Mateo, Alain Denis

International Journal of Speleology

Understanding the cave’s ventilation system is important for determining how the cavity interacts with external airflow. This requires a well-designed monitoring system. This article addresses these key aspects: how to build a monitoring system for cave air parameters and how to assess the ventilation of a cave. We proposed a flowchart to help address the issues in: 1) the modularity of a monitoring system, 2) the use of “homemade device” or “ready to use device”, 3) the frequency of measure and its effect on the electrical consumption, 4) the duration of the survey, and 5) the accessibility of the recorded …

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The Few-Nexus: Using Soil To Grow Meaning And Relevance In Undergraduate General Education Earth Science Courses, Katherine Mccarville Mar 2025

The Few-Nexus: Using Soil To Grow Meaning And Relevance In Undergraduate General Education Earth Science Courses, Katherine Mccarville

National Collaborative for Research on Food, Energy, and Water Education (NC-FEW)

Soils are central to human survival, through their critical roles in regulating water supplies and providing the medium for most agricultural productivity. Even as fewer and fewer students know where their water and food come from, and where their wastes go, soils tend to be under-emphasized in Earth science general education courses. Combining a place-based focus on soils with the FEW-Nexus model provides an integrating context for concepts and information that students sometimes perceive as disconnected and irrelevant to them. This approach can transform the experiences and learning of undergraduate students in the Earth science general education curriculum.

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Refugium Amidst Ruins: Unearthing The Lost Flora That Escaped The End-Permian Mass Extinction, Huiping Peng, Wan Yang, Mingli Wan, Jun Liu, Feng Liu Mar 2025

Refugium Amidst Ruins: Unearthing The Lost Flora That Escaped The End-Permian Mass Extinction, Huiping Peng, Wan Yang, Mingli Wan, Jun Liu, Feng Liu

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Searching for land refugia becomes imperative for human survival during the hypothetical sixth mass extinction. Studying past comparable crises can offer insights, but there is no fossil evidence of diverse megafloral ecosystems surviving the largest Phanerozoic biodiversity crisis. Here, we investigated palynomorphs, plant, and tetrapod fossils from the Permian-Triassic South Taodonggou Section in Xinjiang, China. Our fossil records, calibrated by a high-resolution age model, reveal the presence of vibrant regional gymnospermous forests and fern fields, while marine organisms experienced mass extinction. This refugial vegetation was crucial for nourishing the substantial influx of surviving animals, thereby establishing a diverse terrestrial ecosystem …

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Characterizing Rainfall Variability Within A Series Of Storms Over Northern California In February 2017, Parker Jan Malek Mar 2025

Characterizing Rainfall Variability Within A Series Of Storms Over Northern California In February 2017, Parker Jan Malek

Dissertations and Theses

In February 2017, a series of storms with associated atmospheric rivers (ARs) made landfall in the US state of California, dropping large amounts of precipitation over the Sierra Nevada Mountains and their western foothills. The rainfall from these ARs, long, narrow bands of water vapor that transport large amounts of water vapor from the tropics to the mid-latitudes, instigated the near-failure of the Oroville Dam located at the southeastern edge of the Feather watershed outside the city of Oroville in the state's Central Valley. This case study provides a synoptic and mesoscale diagnosis of the drivers of rainfall pulses that …

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Enhancing Tree Species Mapping In Arkansas’ Forests Through Machine Learning And Satellite Data Fusion: A Google Earth Engine–Based Approach, Abdullah Al Saim, Mohamed Aly Mar 2025

Enhancing Tree Species Mapping In Arkansas’ Forests Through Machine Learning And Satellite Data Fusion: A Google Earth Engine–Based Approach, Abdullah Al Saim, Mohamed Aly

Geosciences Faculty Publications and Presentations

Arkansas' subtropical climate nurtures extensive forested regions, particularly within the Ozark-St. Francis and Ouachita National Forests. Despite this, the state lacks an up-to-date high-resolution map detailing the distribution of tree species within its forests. This study harnesses the power of machine learning, specifically the Random Forest (RF), Gradient Tree Boosting (GTB), Support Vector Machine (SVM), and K-Nearest Neighbors (K-NN) classifiers, within the Google Earth Engine (GEE) framework. These classifiers are applied to classify tree species distribution in Arkansas' forests by integrating data from various sources, including Sentinel-1/-2, Landsat-8, and the National Agriculture Imagery Program (NAIP). The study evaluates the classification …

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Closing Ceremony Speech, S. Ray Smith Mar 2025

Closing Ceremony Speech, S. Ray Smith

IGC Proceedings (1977-2023)

No abstract provided.

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Soil Compaction And Novel Traffic Systems In Ryegrass Grown For Silage: Effects On Herbage Yield, Quality And Nitrogen Uptake, J T. Douglas, C E. Crawford Mar 2025

Soil Compaction And Novel Traffic Systems In Ryegrass Grown For Silage: Effects On Herbage Yield, Quality And Nitrogen Uptake, J T. Douglas, C E. Crawford

IGC Proceedings (1977-2023)

Grassland soils, on which the crop is managed for conser­vation as silage, receive large amounts of vehicle and machinery traffic : rolling and multiple slurry and fertilizers applications, plus multiple harvests, are all activities which are potentially damaging to soil and sward. A number of short-term studies in the UK (Frame, 1987 and Frost, 1988) and elsewhere (Luten and Roozeboom, 1976, and Rasmussen and M¢ller, 1981) have indicated that dry matter yield can be reduced as a consequence of stress imparted to soil by agricultural tyres. Nevertheless, there is a general lack of information on the influence of soil compaction …

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Contribution Of Red Clover To Maize Grain Yields, K D. Johnson, D K. Greene, J H. Cherney Mar 2025

Contribution Of Red Clover To Maize Grain Yields, K D. Johnson, D K. Greene, J H. Cherney

IGC Proceedings (1977-2023)

Renewed emphasis has been placed on crop rotation systems that include a perennial legume. Reasons for this interest include protection of soil from erosion, protection of ground water from nitrate contamination, reduction of soil compac­tion, and potential for fewer inputs which could reduce costs of grain production. Barnes et al. (1985) reported that a nondormant alfalfa (Medicago sativa L.) selected for increased Nin the root and crown had similar summer herbage yield as adapted dormant cultivars, but provided 62 % more symbiotically fixed N for a following crop than dormant cultivars. If most benefit is to be derived from cultivars …

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Analysis Of The Effect On N Nutrition On Dry Matter Yield Of A Sward By Reference To Potential Yield And Optimum N Content, G Lemaire, F Gastal, J Salette Mar 2025

Analysis Of The Effect On N Nutrition On Dry Matter Yield Of A Sward By Reference To Potential Yield And Optimum N Content, G Lemaire, F Gastal, J Salette

IGC Proceedings (1977-2023)

Previous work has shown that the N content of a sward could be related to the dry matter accumulation during the course of the regrowth by the following equation : N % = a(Wtb, where W is the weight of aboveground biomass and N % the N concentration of dry matter (Salette & Lemaire, 1981). The coefficient a represents the N % for an aerial biomass of I t/ha, and b characterizes the degree of dilution of N during the regrowth. When b = 0, N % remains constant during the regrowth. If b = I, there is an increase …

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Nitrogen Fixation In Mixed Pastures Under Two Grazing Intensities, R O. Refi, C A. Navarro, C J. Escuder Mar 2025

Nitrogen Fixation In Mixed Pastures Under Two Grazing Intensities, R O. Refi, C A. Navarro, C J. Escuder

IGC Proceedings (1977-2023)

In the Humid Pampa, 10 millions of ha present intrazonal hydromorphic alkaline soils with low P assimilable content and cyclic floods and droughts. Gramineous native ranges utilized for extensive cattle raising with low productivity levels occupy 70 % of the area. The lack of adapted legume and grass genotypes and little information about grazing management makes it difficult to increase production through implanted pastures due to their low persistence (Darwich and Gonzalez, 1982). To modify this situation an interdisciplinary study of four forage mixtures integrated by promising germplasm for that conditions was carried out. This paper is part of that …

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Strategies Of Fertilizer Nitrogen Applications To Grassland For Beef: Effects On Production And Soil Mineral Nitrogen, N M. Titchen, R J. Wilkins, L Philipps, D Scholefield Mar 2025

Strategies Of Fertilizer Nitrogen Applications To Grassland For Beef: Effects On Production And Soil Mineral Nitrogen, N M. Titchen, R J. Wilkins, L Philipps, D Scholefield

IGC Proceedings (1977-2023)

Experiments in Britain have shown beef production increases with fertilizer-N application to grazed grassland up to at least 300 kg N/ha (Wilkins et al., 1987; Baker and Mayne, 1988). However in view of the small offtake of N in the animal products (c.30 kg/ha) there is increased concern on the fate of the applied N, particularly in relation to loss of nitrate by leaching (Garwood and Ryden, 1986). This paper reports a 3-year experiment which examined the impact on production and on N movements of different strategies of fertilizer-N appli­cation and of the effects of removing grazing livestock at the …

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Biomass Production And Nitrogen Transfer In Mixed Cropping With Glycine Max (L) Merr. And Sorghum Biocolor Moench, S Ogata, K Kuwata, H Saneoka, K Fujita Mar 2025

Biomass Production And Nitrogen Transfer In Mixed Cropping With Glycine Max (L) Merr. And Sorghum Biocolor Moench, S Ogata, K Kuwata, H Saneoka, K Fujita

IGC Proceedings (1977-2023)

It is well known that the mixed-cropping of legumes and grasses benefits the productivity and management of pastures (Ogata et al., 1986; Kawamoto et al., 1983). However, the effect of mixed-croppings on forage biomass production, and how to transfer N fixed to the associated gramineous plants in fields of low N fertility, is less well known (Simpson, 1965). The N accumulation and the transference ofN fixed in mix­tures of forage type soybean and sorghum were studied as a model system.

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Changes In Vegetation Of Various Meadows Under Differential Mineral Fertilization, S Benedycki, S Grzegorczyk, M Mlynarczyk, K Grabowski Mar 2025

Changes In Vegetation Of Various Meadows Under Differential Mineral Fertilization, S Benedycki, S Grzegorczyk, M Mlynarczyk, K Grabowski

IGC Proceedings (1977-2023)

Permanent meadows and pastures occurring in the Mazurian Lake District (North-eastern part of Poland) constitute 32 % of arable lands. Most meadows are situated on peat soils (Olkowski, 1972). Continuous and successive changes take place in such populations. The moment some species decline, the number of others increases which are better adjusted to site conditions or human activity such as fertilization and the way of land use. These changes occur with different intensity depen­ding on fertilizer doses, land use and site conditions which have not been well recognized with regard to permanent meadows (Olkowski and Olesinski, 1976, Eilart, 1986). Determination …

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Developing Effective Nutrient Seed Coatings For Grasses And Legumes, J M. Scott Mar 2025

Developing Effective Nutrient Seed Coatings For Grasses And Legumes, J M. Scott

IGC Proceedings (1977-2023)

Seed coatings provide a unique opportunity to supply developing seedlings with a source of nutrients to which each sown seedling has preferential access compared to neighbour­ing weeds, thus providing the seedlings with a competitive advantage during pasture establishment. A study of commer­cially prepared nutrient coatings (containing nitrogen [NJ, phosphorus [P] and sulfur [SJ) applied to seeds of perennial rye­grass showed that whilst the S component of the coating was effective, the P component was only partially effective, and the N component was ineffective in alleviating the respective soil nutrient deficiencies (Scott et al., 1985). The successful development of nutrient seed …

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The Impact Of Renovation And Phosphate Fertilization On The Productivity Of Pastures In Uruguay, J A. Garcia Mar 2025

The Impact Of Renovation And Phosphate Fertilization On The Productivity Of Pastures In Uruguay, J A. Garcia

IGC Proceedings (1977-2023)

Natural grasslands in Uruguay produce low yields of poor quality herbage and therefore intensive farming is based upon sown pastures of temperate species. Although quite productive, these pastures show high instability and after reaching a peak in the second year, herbage yields rapidly go down due to a consistent legume decline. They usually end up in the fourth year in a low producing grassy sward dominated by perennial grasses like tall fescue or by bermudagrass which is endemic in the cropping/pasture area. Thee lack of persistence is also common to other countries of the region and although the effects of …

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Sur Les Teneurs En Molybedne Des Plantes Fourrageres Des Sols Liasiques Du Bassigny - Consequences Zootechniques, L Duval Mar 2025

Sur Les Teneurs En Molybedne Des Plantes Fourrageres Des Sols Liasiques Du Bassigny - Consequences Zootechniques, L Duval

IGC Proceedings (1977-2023)

En 1943, Ferguson et ses collaborateurs mirent en evidence que la teneur elevee en molybdene des plantes fourrageres est la cause d'une maladie des ruminants appelee scouring ou teartness et observee par Clarke (1855) sur les sols liasiques du Somerset (Grande-Bretagne); ils montrerent aussi que cette • intoxication molybdique ou molybdenose est prevenue et guerie par !'ingestion de cuivre (Ferguson et al., 1943). En France, c'est aussi sur des sols liasiques que des cas aigus de molybdenose ont ete identifies par Fretet (1959), a Is-en­Bassigny (Haute-Marne). Des determinations, effectuees par Flon (1968), confirmerent !'existence de teneurs elevees en molybdene clans …

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Effects Of Changes In Fertilizer Use On The Composition And Productivity Of Permanent Grassland In Relation To Agricultural Production And Floristic Diversity, R J. Wilkins, A Hopkins, F W. Kirkham, C Sargent, O Mountford, C Dibb, J Gilbey Mar 2025

Effects Of Changes In Fertilizer Use On The Composition And Productivity Of Permanent Grassland In Relation To Agricultural Production And Floristic Diversity, R J. Wilkins, A Hopkins, F W. Kirkham, C Sargent, O Mountford, C Dibb, J Gilbey

IGC Proceedings (1977-2023)

More than 50 % of enclosed grassland in Britain comprises swards older than 20 years. There is much variation both in fer­tiliser inputs and in stocking rates, with the trend for increased intensity in use over the last 40 years now being succeeded by increased concern for nature conservation and the protection of the environment. In some areas financial incentives are given for the adoption of management practices intended to increase sward botanical diversity, but there is little information on the rates of change in botanical diversity and production as the management of an old sward is changed with either …

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Phosphorus Requirement For Establishment Of Tropical Forage Grasses And Legumes, J A. Gomide Mar 2025

Phosphorus Requirement For Establishment Of Tropical Forage Grasses And Legumes, J A. Gomide

IGC Proceedings (1977-2023)

Soil phosphorus level is a limiting factor for successfull for­age establishment which, in turn, determines pasture pro­ductivity. Recommendations of P fertilization should not only be based on the available PO4 but should consider the soil P04 buffer capacity and the P critical value for the crop to be grown (Novais and Kamprath, 1979). This study aimed at the determ­inations of P critical doses and levels for the establishment of four species of Brachiaria and four tropical legumes, in five soils.

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F.A.O Design K*B*P Trials In The Mid-Altitude Zone Of Yunnan Province, Southern China, J Bruce-Smith, Yang Guo-Rong, Huang Bi-Zhi, Li Ji-Xin Mar 2025

F.A.O Design K*B*P Trials In The Mid-Altitude Zone Of Yunnan Province, Southern China, J Bruce-Smith, Yang Guo-Rong, Huang Bi-Zhi, Li Ji-Xin

IGC Proceedings (1977-2023)

The Project is investigating the development of « improved pastures » as a practical way to increase ruminant livestock production. Some preliminary results of fertilizer requirements, indicated that K and B may be required as well as P (Wang el al., 1985) for the establishment of such pastures in this mid-alti­tude (2,000 m) transitional sub-tropic-temperate zone of Yunnan. The objective of this paper is to present some experiences from applying the Hauser (1971) truncated fac­torial design trials (widely used by FAO to obtain N, P, K, fert­ilizer recommendations for cereal crops) to a pasture establish­ment situation where P. K and …

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The Effects Of Reducing Or Stopping Fertilizer On New Zealand Dairy Pastures, M B. O'Connor, C Feyter, A.H C. Roberts Mar 2025

The Effects Of Reducing Or Stopping Fertilizer On New Zealand Dairy Pastures, M B. O'Connor, C Feyter, A.H C. Roberts

IGC Proceedings (1977-2023)

New Zealand agriculture with its reliance on legume-based pastures to supply nitrogen has a requirement for fertilizer inputs of phosphorus, sulphur, potassium and to a lesser extent, magnesium and various trace elements. The soils in the two main dairying regions of New Zealand (Waikato, Taranaki) are formed from volcanic ash parent material and are highly P retentive. Traditionally dairy pastures on such soils have been developed using heavy applications of P.K.S. fertil­izers (750-1000 kg.ha-1 .year-1). Such rates have often continued for 10-20 years or more and scientists have repeat­edly questioned the need for continued high inputs of fertilizer (Hutton, 1977; …

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Effect Of Nitrogen Fertilization In Combination With Potassium And Phosphorus And Cutting Frequency On The Yield Of Brachiaria Ruzizensis In Adamawa, Cameroon, E T. Pamo, D Pieper Mar 2025

Effect Of Nitrogen Fertilization In Combination With Potassium And Phosphorus And Cutting Frequency On The Yield Of Brachiaria Ruzizensis In Adamawa, Cameroon, E T. Pamo, D Pieper

IGC Proceedings (1977-2023)

Fertilizers have been shown to increase forage yields under some conditions (Owensby and Smith, 1975), but has very little effect under other conditions (Stoddart et al., 1975). Thus in recent years a great deal of attention has been focussed on the ways and possibilities of increasing forage production by fertil­ization. Various experiments have been conducted on the response of Brarhiaria ruziziensis Germain and Evrad, one of the best perennial forage grasses of the region, to fertilization at Wakwa Animal Research Station. Yonkeu et al., (1986) indicated that application of phosphorus did not lead to improved yield of the forage on …

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Fixation De L’Azote Chez Le Trèfle Blanc (Trifolium Repens L.) Interactions Entre Le Deficit Hydrique Et La Fertilization Potassique, A Guckert, L Shamsun Noor, C Robin, D Schontz Mar 2025

Fixation De L’Azote Chez Le Trèfle Blanc (Trifolium Repens L.) Interactions Entre Le Deficit Hydrique Et La Fertilization Potassique, A Guckert, L Shamsun Noor, C Robin, D Schontz

IGC Proceedings (1977-2023)

Le role du potassium au niveau de l'etat hydrique des vege­taux et notamment des processus d'osmoregulation est bien connu (Mengel, 1984). Dans ce contexte nous avons cherche a determiner l'effet d'un apport d'engrais potassique sur le com­portement du trefle blanc en situation de deficit hydrique. Nos observations ont porte sur ]'evolution du potentiel de base, de l'activite photosynthetique et de la fixation d'azote.

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White Clover (Trifolium Repens L.) For Low Input Pastoral Farming Systems, A D. Mackay, J R. Caradus Mar 2025

White Clover (Trifolium Repens L.) For Low Input Pastoral Farming Systems, A D. Mackay, J R. Caradus

IGC Proceedings (1977-2023)

In temperate regions, white clover (Trifoliurn repens L.) is the predominant legume in pastures, because while fixing N it is able to withstand the stresses of grazing (Brougham et al., 1978). White clover is however a poor competitor for soil phos­phate (P). This is of particular significance when many soils in New Zealand and throughout the world are P deficient. Regu­lar inputs of P fertilizer are required to maintain the vigour and productivity of this forage legume. The increasing costs of manufacture and application of P fertilizer and at the same time the general decline in demand for agricultural …

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The Effect Of Adjusting Soil Availbale N/P Ratio Through Fertilizing On The Growth Of Alfalfa, Zhongping Li, Shuzhen Wan, Jianqiang Zhao Mar 2025

The Effect Of Adjusting Soil Availbale N/P Ratio Through Fertilizing On The Growth Of Alfalfa, Zhongping Li, Shuzhen Wan, Jianqiang Zhao

IGC Proceedings (1977-2023)

Our past experiments indicated that on calcareous soils, growing alfalfa for 5-7 years without phosphorus application led too large a soil available N/P ratio to keep the normal yield and quality of alfalfa production (Lin et al., 1964; Li, 1972). If phosphorus can be added sufficiently when alfalfa is grown, not only the Rhizobium nitrogen fixation can be promoted to keep a proper N/P ratio for alfalfa growth, but also a beneficial condition can be created for the following crops. (Li et al., 1988 ; Li, 1983).

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Alimentation Minerale, Niveau Hydrique Et Utilization De L’Eau Par La Luzerne, Micheline Anneessens Mar 2025

Alimentation Minerale, Niveau Hydrique Et Utilization De L’Eau Par La Luzerne, Micheline Anneessens

IGC Proceedings (1977-2023)

L'eau est souvent un facteur limitant !es rendements puisque des problemes se posent au niveau de sa repartition dans l'es­pace et dans le temps. Aucune etude n'a encore montre comment dose et composi­tion d'engrais interagissent avec l'humidite du substrat sur ]'utilisation de l'eau par une plante fourragere forte consomma­trice de cette ressource.C'est dans ce but que le present essai a ete realise sur la luzerne.

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