Download or read book The Role of PH Soil Type Organic Matter Content and Non microbial Reactions on Pesticide Degradation in Surface and Vadose Zone California and Hawaii Soils written by Amy Beth Jaquess and published by . This book was released on 1991 with total page 292 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Dissertation Abstracts International written by and published by . This book was released on 1992 with total page 830 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Acquisition List written by University of Hawaii at Manoa. Library. Hawaiian Collection and published by . This book was released on 1993 with total page 306 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book American Doctoral Dissertations written by and published by . This book was released on 1991 with total page 724 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Effects of PH Organic Matter and Zinc Metal on the Degradation of Pesticides in Model Soil Disposal Systems written by David Melvin Hodapp and published by . This book was released on 1992 with total page 524 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Bibliography and Index of Geology written by and published by . This book was released on 1992 with total page 1464 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Sorption and Degradation of Pesticides and Organic Chemicals in Soil written by Daniel M. Linn and published by . This book was released on 1993 with total page 292 pages. Available in PDF, EPUB and Kindle. Book excerpt: Reports the current thinking on the role that adsorption may play in the rate and extent of an organic compound's degradation in the soil. Among the topics of the 14 papers are diazinon degradation and dissipation in the root zone, the reductive dechlorination of hexachlorobenzene in wetland soils, and the utility of sorption and degradation parameters from the literature for site-specific pesticide impact assessments. Proceedings from an October 1991 symposium in Denver. No index. Annotation copyright by Book News, Inc., Portland, OR
Download or read book Organic Matter Amendments Improve Soil Function in California Agroecosystems written by Yocelyn Briceyda Villa and published by . This book was released on 2021 with total page 218 pages. Available in PDF, EPUB and Kindle. Book excerpt: Loss of organic matter (OM) from soil through degradation can lead to decline in soil structure, depletion of plant nutrients, enhancing mineralization of organic compounds and contribute to climate change through the release of greenhouse gas emissions. To address this, it is important to identify and expand our current understanding of the management practices that ensure that the functions and services of soils in agricultural lands are maintained for the long-term. Sustainable agriculture aims to meet society's needs for food, feed, and fiber, while protecting natural resources and is primarily guided by the quality of and aims to maintain or improve health of soils. A management practice that directly benefits soil quality, through the enhancement of soil organic matter (SOM), is the use of organic matter amendments (OMA). OMAs are a group of organic materials that are rich in nutrients that can be recycled back to the soil and can have positive effects for improving soil conditions and properties, and are proposed as a climate change mitigation strategy. Through extensive field, laboratory studies, and advanced analytical techniques, I show the potential benefits of recycling organic matter amendments into agricultural soils in California. Three projects were established and make up the three chapters of my dissertation: the first project focused on how the application of two different types of composts in almond orchards influenced soil fertility and nutrient cycling. Main findings from this chapter show that the applications of these OMA were heavily influenced by soil texture. After two years of OMA application there was an improvement in soil fertility. The second chapter focused on how long-term application of biosolids in agricultural soils influences carbon content, specifically focusing on the importance of accounting for deep soil carbon in order to determine a soils climate change mitigation potential in three sites in northern California. Main findings show that application rate of biosolids is not a determining factor when it comes to carbon accounting, but management practices play a bigger role. Additionally, not accounting for deep soil carbon leads to an underestimation of carbon sequestration in biosolid amended soils. Chapter 3 builds off Chapter 2, and investigates the stability of this C and N by determining what pools in the soil they are in. These different pools will provide insight on how vulnerable these reservoirs are to management induced changes which can contribute to C and N losses. Overall findings show that long-term amended soils contribute increase carbon content associated to unprotected pools in surface soils where it is easier for microbes to mineralize. Carbon content in deeper soils show that the carbon is associated to physically protected and mineral associated pools, indicating this carbon to be more persistent. Overall, these findings show that site conditions, measurement methodology, and management practices influence the potential of OMA to be beneficial to soil fertility and climate beneficial.
Download or read book Environmental Impacts of Soil Component Interactions written by P. M. Huang and published by CRC Press. This book was released on 1995-03-29 with total page 302 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book addresses the interactions of soil minerals with organics and microbes and their impacts on the dynamics, transformations, and toxicity of metals, metalloids, other inorganics, and xenobiotics that affect land quality and ecosystem health. It is the result of the work group on "interactions of soil minerals with organic components and microorganisms" in the International Society of Soil Science.
Download or read book The Role of Organic Matter Quality and Mineral Surfaces for the Sorption of Chlorpyrifos and Diazinon on Soils Sediments and Suspended Estuary Sediment written by Andrew Lawrence Sayers-Fay and published by . This book was released on 2006 with total page 342 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Leaching of Pesticides in Selected Hawaii Oxisols and Andisols as Influenced by Soil Profile Characteristics written by Robert Thomas Gavenda and published by . This book was released on 1996 with total page 44 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Environmental Fate of Two Herbicides in Soils written by Amrith S. Gunasekara and published by . This book was released on 2007 with total page 194 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Ground Water Vulnerability Assessment written by National Research Council and published by National Academies Press. This book was released on 1993-02-01 with total page 227 pages. Available in PDF, EPUB and Kindle. Book excerpt: Since the need to protect ground water from pollution was recognized, researchers have made progress in understanding the vulnerability of ground water to contamination. Yet, there are substantial uncertainties in the vulnerability assessment methods now available. With a wealth of detailed information and practical advice, this volume will help decision-makers derive the most benefit from available assessment techniques. It offers: Three laws of ground water vulnerability. Six case studies of vulnerability assessment. Guidance for selecting vulnerability assessments and using the results. Reviews of the strengths and limitations of assessment methods. Information on available data bases, primarily at the federal level. This book will be indispensable to policymakers and resource managers, environmental professionals, researchers, faculty, and students involved in ground water issues, as well as investigators developing new assessment methods.
Download or read book The Effects of Various Soil Factors and Amendments on the Degradation of Pesticide Mixtures in Waste Disposal Systems written by Sarah Roati Schoen and published by . This book was released on 1985 with total page 522 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Biochar for Environmental Management written by Johannes Lehmann and published by Routledge. This book was released on 2012-05-16 with total page 450 pages. Available in PDF, EPUB and Kindle. Book excerpt: Biochar is the carbon-rich product when biomass (such as wood, manure or crop residues) is heated in a closed container with little or no available air. It can be used to improve agriculture and the environment in several ways, and its stability in soil and superior nutrient-retention properties make it an ideal soil amendment to increase crop yields. In addition to this, biochar sequestration, in combination with sustainable biomass production, can be carbon-negative and therefore used to actively remove carbon dioxide from the atmosphere, with major implications for mitigation of climate change. Biochar production can also be combined with bioenergy production through the use of the gases that are given off in the pyrolysis process. This book is the first to synthesize the expanding research literature on this topic. The book's interdisciplinary approach, which covers engineering, environmental sciences, agricultural sciences, economics and policy, is a vital tool at this stage of biochar technology development. This comprehensive overview of current knowledge will be of interest to advanced students, researchers and professionals in a wide range of disciplines.
Download or read book Soil Microbial Enzyme Responses to Changes in Temperature and Nutrient Additions Across Hawaiian Gradients in Mineralogy and Nutrient Availability written by Taylor Leigh McCleery and published by . This book was released on 2014 with total page 121 pages. Available in PDF, EPUB and Kindle. Book excerpt: Microbial enzyme activities are the direct agents of organic matter decomposition, and thus play a crucial role in global C (C) cycling. Global change factors like anthropogenic nutrient inputs and warming have the potential to alter the activities of these enzymes, with background site conditions likely driving responses. We hypothesized that enzyme activities in sites with high background soil nutrient and/or C availability would be less sensitive to nutrient additions than nutrient-poor sites. We also hypothesized that sites poor in nutrients and/or C would show greater sensitivity to changes in temperature. To test our hypotheses we used long- and short-term nutrient additions combined with laboratory temperature incubations to assess changes in enzyme activities for 8 common soil enzymes that acquire nitrogen (N), phosphorus (P) and C from organic matter. We collected mineral soils (0-10 cm depth) from 8 Hawaiian sites that provided maximum variation in nutrient availability and background soil C. Soils were sieved, pooled by site, and homogenized prior to a laboratory addition of a simple C (sucrose), N, and/or P in full factorial design. The 8 soils also were incubated at 7 temperatures from 4 - 40 ðC. We found that the laboratory fertilizations altered enzyme activities, and that temperature sensitivities varied significantly among sites. Across the 8 sites, laboratory sucrose+N and sucrose+NP additions increased C-, N-, and P- acquiring enzymes activities (p
Download or read book Imazosulfuron Degradation Under Simulated California Rice Field Conditions written by Caitlin Carolyn Rering and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Pesticides are a crucial element of current pest management practices, yet can have unintended ecological consequences. Investigations of pesticide fate provide crucial information about the ability of these contaminants to move and transform in the environment, but often struggle to encompass the vast variability exhibited in nature. Ubiquitous solutes like salts, dissolved organic matter, and the presence of other agrochemicals may enhance, reduce, or have no effect on the photolytic and microbial degradation rates of pesticides. The present investigation aims to expand the understanding of imazosulfuron (IMZ) degradation in the presence of selected environmental species to facilitate better predictions of its persistence. Lab-based microcosm studies allow for constrained experiments, where a single variable may be changed and its effects observed. IMZ and its degradation products in soil and water were evaluated using phytotoxicity tests and liquid chromatography coupled to triple quadrupole mass spectrometry. IMZ’s photolytic transformation rate under simulated solar radiation was rapid, corresponding to a field half-life of approximately 4 days. Rates were unchanged in solutions representative of a salinized field, but were slower in unfiltered field water vs. ultrapure lab water. The data suggests that regardless of source material, dissolved organic matter (DOM) acts as an ‘inner-filter’, reducing photon availability, rather than enhancing IMZ photodegradation via the production of reactive species. Non-toxic transformation products were formed and rapidly degraded, due to their chromophoric nature. The mechanism driving IMZ photolysis was investigated using scavenging experiments. This approach selectively removes reactive species (e.g., hydroxyl radical, triplet excited-states) from the irradiated solution, and any resulting differences in rates (or lack thereof) are used to interpret that particular species’ contribution to overall photodegradation. Experiments revealed direct photolysis, through the singlet excited-state, was the main reaction pathway. Photodegradation rates will therefore be enhanced in hypoxic water with minimal light attenuation (commonly observed in CA rice fields). The soil degradation of IMZ under aerobic flooded conditions was evaluated. Soils were dosed with both IMZ and thiobencarb, to reflect the current commercial formulation available in CA. Mixed applications of pesticides can alter soil organism communities, thereby changing observed degradation rates. Dissipation of both herbicides was unchanged in dual or individual application regimes. IMZ’s half-life was 29±2 d and thiobencarb was recalcitrant. Germination and growth inhibition tests evaluated the capacity of soil degradation to reduce the combined phytotoxicity of IMZ and thiobencarb in soil and water residues at the end of the state-mandated field water holding period (30 d). Lemna minor growth was inhibited by aqueous IMZ residues after the holding period. However, previous studies show photodegradation should rapidly remove IMZ from water in the field (>98% in ~24 d). Germination inhibition of Lactuca sativa was not observed in soil at any point, but phytotoxicity was observed in overlying water collected upon initial application. Inhibition was subsequently eliminated at the end of the holding period. By examining IMZ’s most efficient dissipation processes within the context of select environmental variables, a more resolved picture of its fate has been captured. This allows for more accurate predictions of IMZ transformations and associated residual toxicity in diverse environments, thereby providing stakeholders with data needed to adopt informed management strategies.
