Download or read book Relationships of Soil extractable and Plant available Phosphorus in Forest Soils of the Eastern Sierra Nevada written by Richard Brian Susfalk and published by . This book was released on 2000 with total page 456 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Forest Soils Research Theory Reality and Its Role in Technology Transfer written by Margaret Gale and published by Gulf Professional Publishing. This book was released on 2005-12-21 with total page 354 pages. Available in PDF, EPUB and Kindle. Book excerpt: This collection represents a unique set of essays on the role of theory in shaping the practice of medicine across disciplinary boundaries. In the context of this volume, "theory” relates to the conceptual models, frameworks, knowledge representations, metaphors and analogies that inform the problem-solving efforts of practitioners seeking to develop novel dialogues both within and across disciplinary boundaries. Contributors to this volume include computational scientists, chemists, medical researchers, biologists and philosophers, all drawing on personal experience in their respective fields to produce a genuinely interdisciplinary range of perspectives on the common theme of theory in medical thinking and multidisciplinary research practice. * Selected and edited papers from the 10th North American Forest Soils Conference held in Saulte Ste. Marie, Ontario, Canada, July 20-24, 2003 * A unique spin-off from Elsevier's highly regarded journal, Forest Ecology and Management * An estimated 400 pages of the latest findings in forest soil ecology from the most prominent researchers in the field

Download or read book Dissertation Abstracts International written by and published by . This book was released on 2001 with total page 834 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Soil Testing as a Guide to Phosphorus Fertilization of Young Pine Plantations in the Coastal Plain written by R. Ballard and published by . This book was released on 1975 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Annual Meetings Abstracts written by American Society of Agronomy and published by . This book was released on 1998 with total page 460 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Assessing Soil Phosphorus Status Under Different Agronomic Land Use written by Carlos Henriquez and published by . This book was released on 2002 with total page 158 pages. Available in PDF, EPUB and Kindle. Book excerpt: The study of the availability of soil phosphorus (P) to crops has been an important issue for years in different agroecosystems around the world. Because of the complex P cycling in soils this has been studied from different points of view. The study of soil P forms has been seen as a possible way to explain many processes and changes occurring in plant-soil interactions. The purpose of this research was to characterize soil P forms under different land uses and evaluate the relationship between different land use areas and the spatial distribution of soil P forms. The study was carried out in Costa Rica on a Typic Hapludand under coffee plantation (Coffea arabica), sugar cane plantation (Saccharum spp.), and secondary forest. A modified Hedley soil P fractionation methodology was used for determining the soil P forms. Means of the relative content of P forms were 0.43% labile-Pi, 6.44% NaOH-Pi, 9.20% HCl-Pi, 32.55% extractable organic P and 51.37% residual-P. Inorganic fertilization was correlated with labile-P, NaOH-Pi, and HCl-Pi forms. In the first experiment the sugar cane yields were correlated with labile-Pi and NaOH-Pi. Organic fertilizer increased the extractable organic P suggesting an accumulation in this form. In the second descriptive study a spatial relationship was found with soil management areas. Sugar cane soil accumulated more P in HCl-Pi, extractable organic P, and residual-Pi forms. Coffee soil had the highest values in labile-Pi and NaOH-Pi that were correlated with the higher rate of fertilizer application. Secondary forest had intermediate values between these two cropped areas. The third experiment showed that under greenhouse conditions P uptake was closely related to labile-Pi and NaOH-Pi suggesting also that a sparingly available P form could be related to P uptake by plants in time. Extractable organic P and residual-P were suggested to act as a sink of the available P forms. It is concluded that under a sustainable crop production framework the adequate input of P is necessary in order to maintain the adequate nutrient supply through time.

Download or read book NBS Special Publication written by and published by . This book was released on 1980 with total page 964 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Role of Iron Oxyhydroxides in Phosphorus Chemistry of Some East Texas Forest Soils written by Amir Hass and published by . This book was released on 2006 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Forest soil phosphorus (P) chemical behavior was evaluated in some mid-rotation fertilized loblolly pine (Pinus taeda L.) plantations in East Texas, that differed in their site drainage characteristics. Forest floor mass and carbon content in the forest floor were determined. Total P (PT) in the forest floor, and total and Mehlich-1 P and citrate dithionite (CD) and acid ammonium-oxalate (AAO) extractable P, Al, Fe, and Mn within the mineral soil upper 100 cm were determined. Colorimetric determination of AAO and CD-extractable P by the molybdenum blue ascorbic acid method, without the use of pre-digestion, was assessed by an automated continuous flow injection system. Phosphorus distribution between different operationally defined solid phases and its relationships with CD and AAO extractable Mn, Al, Fe among depth, site, drainage class and treatment were evaluated. Soil P forms were highly correlated with iron oxides across sites, drainage classes, treatments, and depth intervals with significant differences in P content and distribution in the soil profile and solid phases among drainage classes. Soil P distribution patterns differed among drainage classes, yet it followed the distribution of the iron oxides. Iron oxide's role as a sink for soil P was higher in the well-drained compared to the poorly drained sites. Amorphous phases of iron oxides were higher in the poorly drained sites and dominated the role of iron oxides as a sink for P under the poor drainage conditions. Fertilization resulted in significantly higher forest floor mass, P content in the forest floor, and total P (PT) and CD-extractable P (Pd) in the soils' upper 10 cm. The treatment effect on P in the forest floor, and on PT and Pd in the upper 10 cm of the mineral soil was equivalent to 6, 19, and 11% of the applied P, respectively. AAO-extractable P was highly correlated with Mehlich-1 P in the fertilized plots. Treatment and site drainage class effects on P accumulation in the different solid phases in the mineral soil and in the forest floor and the potential contribution of these pools to P availability in subsequent rotations, following clearcutting, are discussed.

Download or read book ABSTRACT INFLUENCE OF ROCK PHOSPHATE ON AVAILABLE PHOSPHORUS AS MEASURED BY PLANT UPTAKE AND SOIL EXTRACTANTS written by JOSE ESPINOSA and published by INIAP Archivo Historico. This book was released on with total page 72 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Relationships Among Phosphorus Soil Tests Forms of Soil Phosphorus and Plant Uptake of Phosphorus for Selected Southwestern Oregon Soils written by Thomas A. Doerge and published by . This book was released on 1978 with total page 236 pages. Available in PDF, EPUB and Kindle. Book excerpt: A diversity in climate, geologic parent material, and soil characteristics exist in Jackson, Josephine, Coos, and Douglas Counties of southwest Oregon. Previous field trials and soil testing results have revealed uncertainties as to the phosphorus (P) status of the soils in this area. Twenty-four sites from nine agriculturally significant soil series in southwest Oregon were studied. Soils were selected on the basis of the parent material from which they were derived, either granitic, basaltic, or sedimentary. A greenhouse pot study with Yamhill wheat as the indicator plant was used in conjunction with a modified Change and Jackson P fractionation procedure to determine the forms of soil P which were most available to plants. The organic-P content of each soil was also determined. The aluminum P (Al-P) and iron P (Fe-P) fractions were the most highly correlated plant available P on most soils, although the organic P fraction of the Coos County soils appeared to be an important source of plant P. The Bray P1 dilute acid-fluoride, Olsen 0.5 M NaHCO3, and Morgan's NaOAc P soil tests were used to estimate plant available P. The Bray P1 and Olsen soil test values were more highly correlated to P uptake by wheat and yield response to P fertilizer than the NaOAc soil test values. The Bray P1 test was more sensitive than the Olsen test at relatively low soil test values. Also only the Bray P1 soil test values were significantly correlated to the organic-P content of the Coos County soils. These results indicate that of the three procedures studied, the Bray P1 method is probably best suited for the estimation of plant available P in the mineral soils of southwestern Oregon.

Download or read book Chemical Abstracts written by and published by . This book was released on 2002 with total page 2626 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Phosphorus Availability and Extractability in Soils Not Deficient in Phosphorus written by Adegboyega Yinka Adepoju and published by . This book was released on 1980 with total page 194 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Soil Phosphorus Pools and Harvest Effects on Soil Solution Chemistry in the Missouri Ozark Highlands written by Gurbir Singh and published by . This book was released on 2013 with total page 347 pages. Available in PDF, EPUB and Kindle. Book excerpt: Forests ecosystems are governed by complex and dynamic nutrient cycles where soil is a major provider of nutrients essential for plant growth. Disturbances occurring in forested ecosystems (timber harvest, fire, and disease breakouts) lead to removal of living biomass which may impact nutrient cycling and can cause changes in soil solution chemistry, nutrient flux, and alter soil moisture and temperature. Missouri Ozark Highland soils are highly weathered and, to maintain long-term sustainability and productivity of forests supported by these soils, understanding harvest operations effect on nutrient loss is of utmost importance. Therefore, the primary objective of this study was to enhance understanding of nutrient dynamics and pools in forested soils of the Missouri Ozark Highlands. The study was divided into two specific research objectives: (1) quantify the influence of clearcutting (CC) and single tree selection forest (STS) regeneration on soil solution chemistry and nutrient flux in low and medium nutrient status soils at Missouri Ozark Forest Ecosystem Project (MOFEP); and (2) identify the importance of geomorphic and soil properties on total and available P concentrations in Ozark Highland soils. To address concerns regarding the depletion of soil nutrients in association with timber harvest in the Missouri Ozark Highlands, soil solution and nutrient flux in low and medium nutrient status soils was monitored in clearcut, single tree selection, and no-harvest management sites (NHM) at MOFEP. Pre-harvest and post-harvest solution samples were collected with throughfall and zero-tension soil solution (ZTS) samplers (15 and 40 cm depths), and samples were analyzed for pH and electrical conductivity (EC), anions (F- , Br- , Cl- , NO2 - , NO3 - , SO4 2- , PO4 3- ), cations (K+ , Na+ , NH4 + , Ca2+, Mg2+, and total aluminum), dissolved organic carbon (DOC), and total nitrogen (TN). Ion exchange resin (IER) samplers (15 and 40 cm soil depths) were used to capture cumulative flux. Pre-harvest and one year post harvest soil samples were collected and analyzed for soil pH, exchangeable concentrations of Ca2+, Mg2+, and K+ , effective cation exchange capacity (ECEC), base saturation (base sat.), extractable acidity (EA), extractable aluminum (EAl), aluminum saturation (Al sat.), total organic carbon (TOC), and total nitrogen (TN). Post-harvest soil solution samples contained significantly greater concentrations of NO3 - , Mg2+, and TN and greater values of EC in the clearcut sites relative to STS and NHM. Mean daily flux measurements captured by IER samplers show significantly greater flux of NO3 - and Mg2+ in post-harvest clearcuts relative to pre-harvest measures. Despite morphological and some chemical differences between low and medium nutrient status soils, no influence of soil nutrient status was observed in this research. Study results demonstrate increased nutrient leaching after clearcutting but minimal changes were observed in STS harvested sites relative to control sites. Missouri forest managers may need to reevaluate and modify this practice to minimize the losses triggered after timber harvesting in order to maintain long-term sustainability and productivity of Ozark forests. To meet the second objective, archived soil samples and soil characterization data were obtained for 50 pedons sampled at MOFEP. Soil chemical analyses were conducted to measure total P, available P, and citrate bicarbonate dithionite (CBD) extractable Fe, Al, and Mn in the samples studied. Linear regression and classification and regression tree (CART) analyses were applied to elucidate relationships between soil P pools and geomorphic and soil chemical properties. Total P and available P in the soils studied ranged from 15.55 to 410.13 mg kg-1 and 3.81 to 30.61 mg kg-1 , respectively. Linear regression analyses indicated a moderate correlation of CBD extractable Mn with total P (r2 = 0.77), Bray-1 available P (r2 = 0.69), and Mehlich-3 available P (r2 = 0.71) for soils overlying Eminence bedrock. The CART analysis identified (1) CBD extractable Mn and total organic C as important variables explaining 39 % of cumulative variation in total P; (2) CBD extractable Mn, and exchangeable Ca as important variables explaining 49% of cumulative variation of Bray-1 available P; and (3) CBD extractable Mn, and pH as important variables explaining 55 % of cumulative variation of Mehlich-3 available P. This research aids in understanding and identifying locations in Missouri Ozark forests where of P pools may be relatively small, thus necessitating careful management and monitoring before and after timber harvest. Results from the soil solution study and P forms enhance our understanding of nutrient leaching and budgets in Ozark Highland soils and can help better understand the impact of timber harvesting on nutrients in highly weathered soils. Study results will serve as a tool to better manage Missouri forests and to formulate future management policies. Furthermore this research can aid in identifying soils which are at risk of depletions for P concentrations after harvesting in Ozark highland landscape.

Download or read book Carbon Nitrogen and Phosphorus Cycling in Forest Soils written by Robert G. Qualls and published by MDPI. This book was released on 2019-06-21 with total page 238 pages. Available in PDF, EPUB and Kindle. Book excerpt: The majority of carbon stored in the soils of the world is stored in forests. The refractory nature of some portions of forest soil organic matter also provides the slow, gradual release of organic nitrogen and phosphorus to sustain long term forest productivity. Contemporary and future disturbances, such as climatic warming, deforestation, short rotation sylviculture, the invasion of exotic species, and fire, all place strains on the integrity of this homeostatic system of C, N, and P cycling. On the other hand, the CO2 fertilization effect may partially offset losses of soil organic matter, but many have questioned the ability of N and P stocks to sustain the CO2 fertilization effect. Despite many advances in the understanding of C, N, and P cycling in forest soils, many questions remain. For example, no complete inventory of the myriad structural formulae of soil organic N and P has ever been made. The factors that cause the resistance of soil organic matter to mineralization are still hotly debated. Is it possible to “engineer” forest soil organic matter so that it sequesters even more C? The role of microbial species diversity in forest C, N, and P cycling is poorly understood. The difficulty in measuring the contribution of roots to soil organic C, N, and P makes its contribution uncertain. Finally, global differences in climate, soils, and species make the extrapolation of any one important study difficult to extrapolate to forest soils worldwide.

Download or read book Extractable Soil Phosphorus Correlation with P Forms in Soil Runoff and Relationships with the Texas P Index as a Nutrient Management Tool for CAFOs written by Freddy J. Jacoby and published by . This book was released on 2006 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Phosphorus (P) inputs into water reservoirs are the primary cause for accelerated eutrophication affecting water quality. Attempts are underway to regulate inputs originating from concentrated animal feeding operations (CAFOs). The purpose of this research was to relate runoff dissolved (DP) and total P (TP) losses to site-specific characteristics from plots in CAFOs and compare them to their corresponding risk assessment using the Texas Phosphorus Index (PI). Initial studies showed that soil test P(STP) methods used in Texas by inductively coupled plasma were highly reproducible regardless of manure source or application rate. However, NH4OAc-EDTA extraction efficiency was increased with respect to other methods as soil conditions became less acidic, probably due to dissolution of the greater portion of Ca-bound P resulting in STP values that could be three times greater than those of Mehlich III for the same soil. Surface application of dairy manure to high pH soils were positively correlated to STP at various soil-sampling depths down to 15 cm. First order linear relationships between STP values and DP concentrations in runoff were statistically significant for extraction methods and sampling depths but were different among different soils under neutral to calcareous conditions. Attempts to reproduce this relationship on fields that received periodic applications of manure or effluent with various incubation periods failed, although there was a single highly significant relationship between STP and runoff DP for different soils when soil conditions were acid (pH

Download or read book The Rate of Depletion of Available Residual Phosphorus in Relation to Soil Properties written by Robert Mitchell Lippert and published by . This book was released on 1984 with total page 322 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Terrestrial Vegetation of California 3rd Edition written by Michael Barbour and published by Univ of California Press. This book was released on 2007-07-17 with total page 734 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thoroughly revised, entirely rewritten edition of what is the essential reference on California’s diverse and ever-changing vegetation now brings readers the most authoritative, state-of-the-art view of California’s plant ecosystems available. Integrating decades of research, leading community ecologists and field botanists describe and classify California’s vegetation types, identify environmental factors that determine the distribution of vegetation types, analyze the role of disturbance regimes in vegetation dynamics, chronicle change due to human activities, identify conservation issues, describe restoration strategies, and prioritize directions for new research. Several new chapters address statewide issues such as the historic appearance and impact of introduced and invasive plants, the soils of California, and more.