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Full-Text Articles in Physical Sciences and Mathematics
Grazing Effects On Some Soil Characteristics In Lar Rangelands, S. A. Javadi, M. Jafari, Gh. Zahedi
Grazing Effects On Some Soil Characteristics In Lar Rangelands, S. A. Javadi, M. Jafari, Gh. Zahedi
IGC Proceedings (1997-2023)
Heavy grazing pressures jeopardise the sustainability of the ecosystem by reducing soil fertility (Dormaar et al., 1998). Different results have been reported of grazing intensities on soil chemical properties, which stem from climate, soil, vegetation, management and kind of animal (Dormaar et al., 1998; Javadi, 2003; Sanadgool, 2002).
Potentialities Of Near Infrared Spectroscopy To Assess Nitrogen, Phosphorus And Potassium Nutrient Status Of Grasslands In The Reunion Island, Philippe Lecomte, Vincent Blanfort, Michael Duru, P. Thomas, P. Grimaud
Potentialities Of Near Infrared Spectroscopy To Assess Nitrogen, Phosphorus And Potassium Nutrient Status Of Grasslands In The Reunion Island, Philippe Lecomte, Vincent Blanfort, Michael Duru, P. Thomas, P. Grimaud
IGC Proceedings (1997-2023)
Controlled mineral fertilisation practices are an important component for sustainable management of grasslands. The assessment of available nutrients for plants and the general recommendations on the level of phosphorus and potassium to apply to grasslands are classically based on classical soil analysis and average regional levels. For nitrogen, mid or long term recommendations cannot easily be derived solely from soil composition, because it may be rapidly leached from the soil. Recent approaches tended to show that herbage plant N (Lemaire & Gastal, 1997), P, K (Duru & Huché, 1997) mineral analyses associated with actual biomass measurement could be useful for …
Heterogeneous Nutrient Distribution Across Dairy Grazing Systems In Southeastern Australia, C. J. P. Gourley, I. Awty, P. A. Durling, J. Collins, A. Melland, S. R. Aarons
Heterogeneous Nutrient Distribution Across Dairy Grazing Systems In Southeastern Australia, C. J. P. Gourley, I. Awty, P. A. Durling, J. Collins, A. Melland, S. R. Aarons
IGC Proceedings (1997-2023)
The Australian dairy industry is largely based on a grazed pasture system, although most cows also consume substantial amounts of imported feed (Fulkerson & Doyle 2001). This trend is expected to increase as the Australian dairy industry continues to intensify. Fertiliser inputs of nitrogen (N), phosphorus (P), potassium (K) and sulphur (S) are still viewed as necessary to maintain adequate pasture and milk production despite the fact that most dairy farms are in net positive balance for all of these nutrients (Reuter 2001). Nutrient losses from dairy farming regions and eutrophication of waterways has gained strong public and political attention …
Effect Of Dairy Effluent On Turnip Nutritive Characteristics, Joe L. Jacobs, G. N. Ward, Frank R. Mckenzie
Effect Of Dairy Effluent On Turnip Nutritive Characteristics, Joe L. Jacobs, G. N. Ward, Frank R. Mckenzie
IGC Proceedings (1997-2023)
In southern Victoria, high summer temperatures and low rainfall lead to low pasture growth and a decline in nutritional value until rainfall commences in autumn. Annual forage crops such as turnips often are used to fill the summer feed gap. Jacobs & Ward (2003) observed that dairy effluent applied at low rates could improve turnip DM yields and crude protein content. Results from the first two years of a 3-year study comparing a range of effluent application rates on turnip leaf and root nutritive characteristics are reported.
Effect Of Dairy Effluent On Turnip Yields, Joe L. Jacobs, G. N. Ward, Frank R. Mckenzie
Effect Of Dairy Effluent On Turnip Yields, Joe L. Jacobs, G. N. Ward, Frank R. Mckenzie
IGC Proceedings (1997-2023)
Dairy effluent is a significant point source in the pollution of waterways. Only 50% of dairy farms in the dryland regions of Victoria, Australia, have suitable dairy effluent systems of which only 25% are managed effectively (IRIS Research 2000). Despite many farmers viewing effluent as an undesirable waste, it contains relatively large amounts of agronomically valuable nutrients especially nitrogen (N) and potassium (K). Results are reported from the first two years of a three year study comparing turnip leaf and root dry matter (DM) responses to a range of dairy effluent rates.
Qtl Analysis Of Mineral Content And Grass Tetany Potential In Leymus Wildryes, S. R. Larson, H. F. Mayland
Qtl Analysis Of Mineral Content And Grass Tetany Potential In Leymus Wildryes, S. R. Larson, H. F. Mayland
IGC Proceedings (1997-2023)
Grass tetany is a metabolic ailment in ruminants, occurring when animals graze rapidly growing C3 grasses with a K/(Mg+Ca) ratio (KRAT) greater than 2.2. High KRAT values have been documented in several forage grasses including diploid Russian wildrye (Jefferson et al., 2001). The objective of this experiment was to identify quantitative trait loci (QTLs) controlling KRAT in allotetraploid wildryes.
Heterogeneous Nutrient Distribution Across Dairy Grazing Systems In Southeastern Australia, C. J. P. Gourley, I. Awty, P. A. Durling, J. Collins, A. Melland, S. R. Aarons
Heterogeneous Nutrient Distribution Across Dairy Grazing Systems In Southeastern Australia, C. J. P. Gourley, I. Awty, P. A. Durling, J. Collins, A. Melland, S. R. Aarons
IGC Proceedings (1997-2023)
The Australian dairy industry is largely based on a grazed pasture system, although most cows also consume substantial amounts of imported feed (Fulkerson & Doyle 2001). This trend is expected to increase as the Australian dairy industry continues to intensify. Fertiliser inputs of nitrogen (N), phosphorus (P), potassium (K) and sulphur (S) are still viewed as necessary to maintain adequate pasture and milk production despite the fact that most dairy farms are in net positive balance for all of these nutrients (Reuter 2001). Nutrient losses from dairy farming regions and eutrophication of waterways has gained strong public and political attention …
Effects Of Fertilization And Legume Introduction On The Forage Production Of Brachiaria Decumbens Pastures, M. R. Correa, Tsutomu Kanno, Manuel C. M. Macedo, J. D. G. Santos Junior, L. G. Beretta
Effects Of Fertilization And Legume Introduction On The Forage Production Of Brachiaria Decumbens Pastures, M. R. Correa, Tsutomu Kanno, Manuel C. M. Macedo, J. D. G. Santos Junior, L. G. Beretta
IGC Proceedings (1997-2023)
A grazing experiment was conducted to examine the effects of P and K fertilization and legume introduction on the forage production of Brachiaria decumbens (BD) pastures. Amount of biomass, dry matter production and forage quality were evaluated on BD pastures where three treatments were applied: without maintenance fertilizer (BD-N), with maintenance fertilizer (BD-F), and BD and Stylosanthes guianensis cv. Mineirao (SG) mixture with maintenance fertilizer (BD-FL). The fertilizer application increased an annual average of biomass and the contents of P and K in the leaves. On the other hand, the legume introduction had a positive influence on crude protein and …
Agronomic Evaluation Of Forage Grasses Under Mature Rubber Plantation, N. L. Costa, Valdinei T. Paulino, A. C. M. Igreja, C. R. Townsend, J. A. Magalhães, R. G. De A Pereira, T. S. Paulino
Agronomic Evaluation Of Forage Grasses Under Mature Rubber Plantation, N. L. Costa, Valdinei T. Paulino, A. C. M. Igreja, C. R. Townsend, J. A. Magalhães, R. G. De A Pereira, T. S. Paulino
IGC Proceedings (1997-2023)
The agronomic performance of seven forage grasses, under a mature rubber plantation, was assessed in a cutting trial carried out at Porto Velho, Rondônia. During the rainy season, the higher dry matter yields were obtained with B. brizantha, P. atratum BRA-9610 and B. humidicola. During the dry season, the grasses more productive were B. brizantha and P. atratum BRA-9610. In both seasons, magnesium and potassium contents did not vary among grasses. During the rainy season, the higher nitrogen and phosphorus contents were obtained with P. regnelli BRA-0159 and, P. guenoarum BRA-3824 and B. humidicola, respectively, while P. atratum …
Contribution Of Dairy Cow Manure To Soil Fertility And Nutrient Redistribution In Pastures, S. R. Aarons, C. R. O'Connor, M. Hall, C. J. P. Gourley
Contribution Of Dairy Cow Manure To Soil Fertility And Nutrient Redistribution In Pastures, S. R. Aarons, C. R. O'Connor, M. Hall, C. J. P. Gourley
IGC Proceedings (1997-2023)
The effects of dairy cow manure on soil fertility were investigated at the site of the long-term phosphorus rate by stocking rate farmlet experiment at the Dairy Research Institute, Ellinbank, in Victoria. Manure increased extractable soil P (Olsen) in the 0 - 5 cm layer after 60 days to 61 mg/kg compared with values of 32 mg/kg in the control soils. Extractable soil K (Colwell) almost doubled under manure pads to 5 cm depth from 642 mg/kg in control soils to 1226 mg/kg in manure treated soils. The effects of grazing management on nutrient redistribution and pasture growth within strip-grazed …
Sources And Rates Of Phosphorus In Improving Degraded Pasture In Brazilian West Amazon, Valdinei T. Paulino, N. L. Costa, C. R. Townsend, J. A. Magalhães, R. G. A. Periera
Sources And Rates Of Phosphorus In Improving Degraded Pasture In Brazilian West Amazon, Valdinei T. Paulino, N. L. Costa, C. R. Townsend, J. A. Magalhães, R. G. A. Periera
IGC Proceedings (1997-2023)
The effects of phosphorus sources (triple superphosphate – TSP, single superphosphate – SSP and partially acidulated rock phosphate – PARP) and rates (0, 50 and 100 kg/ha of P2O5 on dry matter (DM) yields and chemical composition of a degraded Brachiaria brizantha cv. Marandu pasture were evaluated in a cutting trial. Phosphorus fertilization, irrespective of sources and rates, showed an effective agronomic technique for pasture recuperation. The grass DM yields and potassium contents were significantly improved by phosphorus application, while weed DM yields were depressed. Irrespective of sources and rates, crude protein, phosphorus, and calcium contents were …
Interactions Between The Effects Of Nitrogen, And Phosphorus, Potassium And Sulphur On Grass Production, J. D. Morton, L. C. Smith
Interactions Between The Effects Of Nitrogen, And Phosphorus, Potassium And Sulphur On Grass Production, J. D. Morton, L. C. Smith
IGC Proceedings (1997-2023)
The interactions between rates of nitrogen (N) and rates of phosphorus (P), potassium (K) or sulphur (S) on yield of ryegrass dominant swards were measured with no return of mown clippings in Southland, New Zealand. In the second year of the trial, the yield response to 176 kg N ha-1 compared with no N increased only slightly with increasing soil Olsen P from 8 to 91 µg g-1 soil. At 352 and 704 kg N ha-1 there was a large increase in the yield response (from 5 to 9.4 and 11 t DM ha-1 respectively) up …
Application Of Near Infrared Reflectance Spectroscopy (Nirs) For Macronutrients Analysis In Alfalfa (Medicago Sativa L.), A. Morón, D. Cozzolino
Application Of Near Infrared Reflectance Spectroscopy (Nirs) For Macronutrients Analysis In Alfalfa (Medicago Sativa L.), A. Morón, D. Cozzolino
IGC Proceedings (1997-2023)
Near infrared reflectance spectroscopy was used to assess the mineral composition of alfalfa (Medicago sativa L.) as a tool for nutritional diagnosis. One hundred and ninety four (n = 194) samples of alfalfa from different locations representing a wide range of soils were used. Samples were reflectance scanned in a NIRS 6500 (NIRSystems, USA) instrument. The coefficients of determination (R2) of the regression estimate of the concentration of nitrogen, calcium, phosphorus, potassium, magnesium and sulphur and the errors in cross validation (SECV) were 0.93 (SECV: 1.6), 0.95 (SECV: 1.3), 0.93 (SECV: 1.9), 0.88 (SECV: 2.8), 0.82 (SECV: …
Effect Of Combined Fertilization On Seed Production Of Xinnong‐1 Bermudagrass, Yanhui Zhang, Abulaiti, Peiying Li
Effect Of Combined Fertilization On Seed Production Of Xinnong‐1 Bermudagrass, Yanhui Zhang, Abulaiti, Peiying Li
IGC Proceedings (1997-2023)
No abstract provided.
The Analysis Of Cation‐Anion Difference Of Six Important Forage, Zhiqiang Li, J. G. Han
The Analysis Of Cation‐Anion Difference Of Six Important Forage, Zhiqiang Li, J. G. Han
IGC Proceedings (1997-2023)
No abstract provided.
Effects Of Phosphorus And Potassium On Alfalfa Seed Quality, Xianguo Wang, Jianguo Han, Zhiguang Geng, Peisheng Mao, Yunwen Wang
Effects Of Phosphorus And Potassium On Alfalfa Seed Quality, Xianguo Wang, Jianguo Han, Zhiguang Geng, Peisheng Mao, Yunwen Wang
IGC Proceedings (1997-2023)
No abstract provided.
What Is The Effect Of Long-Term Cutting Versus Abandonment On The Vegetation And Chemical Properties In The Soil And The Herbage Of A Mountain Hay Meadow (Polygono-Trisetion)?, Pavlů Lenka, Pavlů Vilém, Hejcman Michal, Gaisler Jan
What Is The Effect Of Long-Term Cutting Versus Abandonment On The Vegetation And Chemical Properties In The Soil And The Herbage Of A Mountain Hay Meadow (Polygono-Trisetion)?, Pavlů Lenka, Pavlů Vilém, Hejcman Michal, Gaisler Jan
IGC Proceedings (1997-2023)
Polygono-Trisetion meadow communities are endangered in Europe. These meadows are common in the Alps, but in the past, such meadows were also common in the western alpine regions of Central Europe. The aim of our experiment was to find a suitable management regime for the maintenance of these Polygono-Trisetion grasslands and its effect on the vegetation and chemical properties of the soil and in the herbage.
Phosphorus And Potassium Fertilizer Application Strategies In Corn–Soybean Rotations, Timothy J. Boring, Kurt D. Thelen, James E. Board, Jason L. De Bruin, Chad D. Lee, Seth L. Naeve, William J. Ross, Wade A. Kent, Landon L. Ries
Phosphorus And Potassium Fertilizer Application Strategies In Corn–Soybean Rotations, Timothy J. Boring, Kurt D. Thelen, James E. Board, Jason L. De Bruin, Chad D. Lee, Seth L. Naeve, William J. Ross, Wade A. Kent, Landon L. Ries
Plant and Soil Sciences Faculty Publications
To determine if current university fertilizer rate and timing recommendations pose a limitation to high-yield corn (Zea mays subsp. mays) and soybean (Glycine max) production, this study compared annual Phosphorous (P) and Potassium (K) fertilizer applications to biennial fertilizer applications, applied at 1× and 2× recommended rates in corn–soybean rotations located in Minnesota (MN), Iowa (IA), Michigan (MI), Arkansas (AR), and Louisiana (LA). At locations with either soil test P or K in the sub-optimal range, corn grain yield was significantly increased with fertilizer application at five of sixteen site years, while soybean seed yield was significantly …
Nutrient Addition Shifts Plant Community Composition Towards Earlier Flowering Species In Some Prairie Ecoregions In The U.S. Central Plains, Lori Biederman, Brent Mortensen, Philip Fay, Nicole Hagenah, Johannes Knops, Kimberly La Pierre, Ramesh Laungani, Eric Lind, Rebecca L. Mcculley, Sally Power, Eric Seabloom, Pedro Tognetti
Nutrient Addition Shifts Plant Community Composition Towards Earlier Flowering Species In Some Prairie Ecoregions In The U.S. Central Plains, Lori Biederman, Brent Mortensen, Philip Fay, Nicole Hagenah, Johannes Knops, Kimberly La Pierre, Ramesh Laungani, Eric Lind, Rebecca L. Mcculley, Sally Power, Eric Seabloom, Pedro Tognetti
Plant and Soil Sciences Faculty Publications
The distribution of flowering across the growing season is governed by each species’ evolutionary history and climatic variability. However, global change factors, such as eutrophication and invasion, can alter plant community composition and thus change the distribution of flowering across the growing season. We examined three ecoregions (tall-, mixed, and short-grass prairie) across the U.S. Central Plains to determine how nutrient (nitrogen (N), phosphorus, and potassium (+micronutrient)) addition alters the temporal patterns of plant flowering traits. We calculated total community flowering potential (FP) by distributing peak-season plant cover values across the growing season, allocating each species’ cover to only those …
Value Of Nutrients In Poultry Litter When Applied In The Fall, Monroe Rasnake, George Kelley
Value Of Nutrients In Poultry Litter When Applied In The Fall, Monroe Rasnake, George Kelley
Soil Science News and Views
The value of nutrients in poultry litter depends not only on how much nitrogen (N), phosphorus (P) and potassium (K) it contains, but also on how it is handled and applied. The following table compares the value of 19 poultry litter samples from Hopkins County analyzed for N, P & K and the litter then spread in the fall. The samples include pullet, breeder and broiler manures, with storage times up to one year. Nutrient values were based on a comparison with urea (46-0-0) at $199/ton, triple super phosphate (0-46-0) at $215/ton and muriate of potash (0-0-60) at $165/ton.
Drawdown Of Soil Test Phosphorus And Potassium Levels By Alfalfa, Kenneth L. Wells, James E. Dollarhide
Drawdown Of Soil Test Phosphorus And Potassium Levels By Alfalfa, Kenneth L. Wells, James E. Dollarhide
Soil Science News and Views
Alfalfa hay production removes large amounts of phosphorus (P) and potassium (K) from soils. Because of this, there is always interest in the reduction of soil test phosphorus (STP) and soil test potassium (STK) levels by high-yielding alfalfa. Periodic soil sampling for 2 years during an on-farm· fertilizer study on a high yielding alfalfa field provided an insight into this.
The Effect Of Rate And Source Of Potassium Fertilizer On Cured Leaf Yield Of Burley Tobacco And Leaf Content And Soil Test Levels Of Potassium And Magnesium, Kenneth L. Wells, James E. Dollarhide, Mark Reese
The Effect Of Rate And Source Of Potassium Fertilizer On Cured Leaf Yield Of Burley Tobacco And Leaf Content And Soil Test Levels Of Potassium And Magnesium, Kenneth L. Wells, James E. Dollarhide, Mark Reese
Soil Science News and Views
In response to questions being asked by tobacco growers about the effectiveness of sulfate of potash magnesia (SPM; 21% K2O and 11% Mg) as coinpared to sulfate of potash (SP; 50% K2O), field studies were conducted during 1993-1994 to compare the two potassium (K) sources for use on burley tobacco. Any effect of SPM on yield of tobacco should be due to Mg since the only difference between the two sources in kind of nutrient contained is the presence of magnesium (Mg) in SPM. To compare the two K sources, we selected field sites low enough …
Production And Nutrient Content Of Broiler Litter, Monroe Rasnake, Mike Williams
Production And Nutrient Content Of Broiler Litter, Monroe Rasnake, Mike Williams
Soil Science News and Views
How much litter is produced in a broiler house in one year? How much nitrogen, phosphorus, and potassium is present in broiler litter? These are questions that concern broiler producers and others who have an interest in the use and safe disposal of broiler litter. A project was initiated with support of the Tennessee Valley Authority and the cooperation of several broiler producers in Carlisle County to help answer these questions.
Estimated Nutrient Content And Uptake By Kentucky's Crops, Kenneth L. Wells, William O. Thom
Estimated Nutrient Content And Uptake By Kentucky's Crops, Kenneth L. Wells, William O. Thom
Soil Science News and Views
A commonly asked question by crop producers is, "how many pounds of plant nutrients do my crops take up?" While the absolute answer to this varies by yield and soil fertility, useful estimates can be made from research data to enable a producer to have a "ballpark" value for nutrient up-take by some of the major crops of Kentucky. The following tables contain estimates of nitrogen (N), phosphorus (P),and potassium (K) contained in certain crops and the amount of N, phosphate (P2O5), and potash (K,O) taken up by tobacco, corn, soybeans, wheat, alfalfa hay, clover grass …
Fall Fertilization And Liming For Tobacco Production, J. L. Sims, Kenneth L. Wells
Fall Fertilization And Liming For Tobacco Production, J. L. Sims, Kenneth L. Wells
Soil Science News and Views
Proper nutrition of tobacco is a prerequisite for achieving high yields of cured leaf possessing desirable marketing characteristics. Together with the variety grown, soils, climate, and curing conditions, a desirable nutrient environment greatly influences yield, quality, and usability of the leaf produced. Late summer and early fall is a good time to select fields for future tobacco crops or to sample this year's tobacco fields which will be used for tobacco next year, and to assess their needs for lime, phosphorus, and potassium. Planning fertilization strategies this fall that lead to increased profit is much more effective than waiting until …
Farm Nutrient Management, William O. Thom
Farm Nutrient Management, William O. Thom
Soil Science News and Views
Nutrient management is becoming a buzz word in today's vocabulary of crop and livestock production. In the past it was applied to efficient management of all nutrient sources used for crop production. More recently it is being used to account for all nutrients used for crop production that are brought onto the farm, removed from the farm in crop and animal products, and reallocated within the farm unit. Nitrogen, phosphorus, and potassium are the nutrients of concern with nitrogen and phosphorus being most important.
Effectiveness Of Surface Application Of Phosphorus And Potassium On Yield Of No-Till Corn Grown On Soils Testing Low Or Medium Below A Depth Of 3 Inches, Grant W. Thomas
Effectiveness Of Surface Application Of Phosphorus And Potassium On Yield Of No-Till Corn Grown On Soils Testing Low Or Medium Below A Depth Of 3 Inches, Grant W. Thomas
Soil Science News and Views
When crops are grown continuously under no-tillage or very minimum tillage, there is a tendency for phosphorus (P) and potassium (K) to become concentrated at or near the soil surface. This occurs when P and K fertilizers are broadcast on the surface and not mixed with the soil as would occur with plowing. The result is a stratification of P and K such that the surface few inches become very high in those nutrients, but soil test levels remain largely unaffected below that. The question is whether high yields of no-till crops can be obtained under these conditions.
Potassium Mineralogy Of Kentucky Soils, Anastasios D. Karathanasis
Potassium Mineralogy Of Kentucky Soils, Anastasios D. Karathanasis
Soil Science News and Views
Feldspars and mica minerals are the two primary natural sources of potassium for most agricultural soils in Kentucky. Potassium feldspars are common mineral constituents of loess deposits in western Kentucky. Mica minerals, although dominant in shales, are also found in variable quantities in siltstone, sandstone and limestone parent materials of soils in the other regions of Kentucky. Because most of the soils in the western Coalfields and western Pennyroyal, and to a lesser extent in eastern Pennyroyal and Bluegrass, are covered by a loess cap of variable thickness, their surface mineralogy has been influenced by the feldspar-rich mineralogy of the …
Using Residual Soil Fertility Effectively, Grant W. Thomas
Using Residual Soil Fertility Effectively, Grant W. Thomas
Soil Science News and Views
During the past 30 years, the use of commercial fertilizer in Kentucky has resulted in increases in the levels of phosphorus and potassium in soils. As might be expected, the soil test levels are higher with tobacco than with any other crop. but all soils for all crops show increases in fertility levels. Comparisons between 1975 and 1985 (the latest year available) show the proportion of samples sent to the University of Kentucky that are medium or high in soil test phosphorus has increased considerably. Even more striking is the decrease in very low values of phosphorus.