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Pertumbuhan Dan Hasil Padi Gogo Hubungannya Dengan Kandungan Prolin Dan 2-Acetyl-1-Pyrroline Pada Kondisi Kadar Air Tanah Berbeda, A. Y. Rahayu, T. A.D. Haryanto, S. N. Iftitah Dec 2016

Pertumbuhan Dan Hasil Padi Gogo Hubungannya Dengan Kandungan Prolin Dan 2-Acetyl-1-Pyrroline Pada Kondisi Kadar Air Tanah Berbeda, A. Y. Rahayu, T. A.D. Haryanto, S. N. Iftitah

Jurnal Kultivasi

Penelitian ini bertujuan untuk mengetahui respons varietas padi gogo pada kadar air tanah berbeda terhadap pertumbuhan, hasil dan kandungan prolin dan 2-acetyl-1-pyrroline biji. Penelitian dilaksanakan di Universitas Tidar Magelang mulai bulan September 2012 sampai dengan Maret 2013. Percobaan menggunakan Rancangan Acak Kelompok Lengkap terdiri atas dua faktor yaitu varietas padi gogo (Inpago Unsoed-1, galur JSPGA 136, varietas Situ-bagendit (non-aromatik) dan varietas Mentik Wangi) dan tingkat kadar air tanah (100 % kapasitas lapang dan 50 % kapasitas lapang). Variabel pengamatan meliputi: tinggi tanaman (cm), jumlah anakan total per rumpun (batang), jumlah anakan produktif (batang), total panjang akar (m), umur berbunga (hst), …


Aplikasi Pupuk Organik Terhadap Hasil Kacang Hijau (Vigna Radiate L.) Di Ultisol, Ida Widiyawati, T. Harjoso, T. T. Taufik Dec 2016

Aplikasi Pupuk Organik Terhadap Hasil Kacang Hijau (Vigna Radiate L.) Di Ultisol, Ida Widiyawati, T. Harjoso, T. T. Taufik

Jurnal Kultivasi

Permasalahan budidaya kacang hijau di Indonesia adalah produktivitas yang masih rendah dan lahan budidaya yang terbatas, sehingga dapat diatasi dengan mengoptimalkan lahan marginal seperti tanah ultisol untuk kegiatan budidaya kacang hijau. Tujuan pene-litian ini adalah untuk mengetahui varietas kacang hijau dan jenis pupuk organik yang mampu menghasilkan produksi tinggi di tanah ultisol. Penelitian dilakukan menggunakan polibag di Screen House, Fakultas Pertanian, Universitas Jenderal Soedirman pada bulan Juli-September 2015. Penelitian menggunakan Rancangan Acak Kelompok Lengkap (RAKL) dengan dua faktor. Faktor pertama adalah varietas kacang hijau yang terdiri atas tiga varietas, yaitu Vima 1, Betet, dan Murai. Faktor kedua adalah jenis pupuk, …


Assessing The Impact Of A Constructed Wetland Biome On The Ecosystem Health Of Cedar Run, Thomas Vasilopoulos, Casey Lee Dec 2016

Assessing The Impact Of A Constructed Wetland Biome On The Ecosystem Health Of Cedar Run, Thomas Vasilopoulos, Casey Lee

Senior Honors Projects, 2010-2019

A wetlands ecosystem is defined as “an area saturated by surface or groundwater at a frequency or duration sufficient to support...a prevalence of vegetation typically adapted for life in saturated soil conditions” (Batzer and Sharitz, 2007). Wetlands serve as biofilters and thus have been used to treat sewage and wastewater, as well as to restore the health of polluted water systems. Solly Walker and Lorinda Palin, owners of a certified natural and biodynamic farm called Avalon Acres located in Broadway, Virginia, constructed a wetland two years ago, using the stream, Cedar Run, that flows through their property. Pollution from agricultural …


Residual Effects Of Nitrogen Fertilization On Soil Nitrogen Pools And Corn Growth, Meghan E. Moser Dec 2016

Residual Effects Of Nitrogen Fertilization On Soil Nitrogen Pools And Corn Growth, Meghan E. Moser

Open Access Theses

Given the dynamic nature of soil nitrogen (N), inorganic N fertilization to corn (Zea mays L.) has potential to alter N pool balance by creating an accumulation or depletion of soil N. Current corn N recommendations in the common corn-soybean rotation of Indiana strive to find the best N rate that maximizes producer profit. Increasing our understanding of soil N will inform producers if they should adjust fertilizer rates for corn to influence maintenance of organic N and Carbon. Our objective was to determine residual N effects from fertilized corn in a corn-soybean rotation by measuring (1) soil N …


Annual Forage Cropping-Systems For Midwestern Ruminant Livestock Production, John Ernest Mcmillan Dec 2016

Annual Forage Cropping-Systems For Midwestern Ruminant Livestock Production, John Ernest Mcmillan

Open Access Dissertations

Annual forage cropping systems are a vital aspect of livestock forage production. One area where this production system can be enhanced is the integration of novel annual forages into conventional cropping systems. Two separate projects were conducted to investigate alternative forage options in annual forage production. In the first discussed research trial, two sets of crops were sown following soft red winter wheat (Triticum aestivum L.) grain harvest, at two nitrogen application rates 56 and 112 kg ha-1 . The first set of crops were C4 summer annuals seeded within two weeks of wheat grain harvest and included, brown …


An Examination Of Geographic Patterns Of Soil Climate And Its Classification In The U.S. System Of Soil Taxonomy, Hans Edwin Winzeler Dec 2016

An Examination Of Geographic Patterns Of Soil Climate And Its Classification In The U.S. System Of Soil Taxonomy, Hans Edwin Winzeler

Open Access Dissertations

Soil climate, the record of temporal patterns of soil moisture and temperature, is an important component of the structure of U.S. Soil Taxonomy. The U.S. Soil Survey has used the Newhall Simulation Model (NSM) for estimating soil climate from atmospheric climate records at weather stations since the 1970s. The current soil climate map of the U.S. was published in 1994 by using NSM runs from selected weather stations along with knowledge-based hand-drawn mapping procedures. We developed a revised soil climate mapping methodology using the NSM and digital soil mapping techniques.

The new methodology is called Grid Element Newhall Simulation Model …


Growth Of Methanogens In The Presence Of Perchlorate Salts: A Study For Possible Life On Mars, John Cale Dec 2016

Growth Of Methanogens In The Presence Of Perchlorate Salts: A Study For Possible Life On Mars, John Cale

Biological Sciences Undergraduate Honors Theses

The Phoenix Lander collected soil samples from Mars, and it detected perchlorate salts in its analysis [1]. As oxidizing agents, perchlorates pose a threat to the hypothesis that there may be microbial life on Mars. Since Mars is very dry, perchlorate may continue to accumulate in the soil. If anaerobic methanogens inhabit Mars, then they must be able to grow in the presence of perchlorate salts. There were four species of methanogens tested in this project. The methanogens were first exposed to small concentrations of calcium perchlorate, and then they were gradually tested at higher concentrations. Growth was measured by …


Cover Crop Establishment And Potential Benefits To Arkansas Farmers, Ashley Elizabeth Humphreys Dec 2016

Cover Crop Establishment And Potential Benefits To Arkansas Farmers, Ashley Elizabeth Humphreys

Graduate Theses and Dissertations

Soybean farmers in Arkansas need best management practices (BMPs) that maximize the benefits of using cover crops including planting date and fertilization recommendations. An evaluation of cover crop species, planting dates, seeding rates, fertilizer rates, and N accumulation aids in providing these BMPs. The first objective of this research is to assess the effect of planting date on biomass production, as well as looking at the interaction of seeding rate or fertilizer rate for legumes or non-legumes, respectively, using Austrian winter pea (Pisum sativum), cereal rye (Secale cereale), black oats (Avena strigosa), wheat (Triticum aestivum), and tillage radish (Raphanus sativus). …


Examining Denitrification In Agricultural Ditch Sediments Vegetated With Rice Cutgrass (Leersia Oryzoides): Modeling Seasonal Variation Across Increasing Levels Of Nitrate Loading And Model Application To Pre-Existing Datasets, Shannon Lee Speir Dec 2016

Examining Denitrification In Agricultural Ditch Sediments Vegetated With Rice Cutgrass (Leersia Oryzoides): Modeling Seasonal Variation Across Increasing Levels Of Nitrate Loading And Model Application To Pre-Existing Datasets, Shannon Lee Speir

Graduate Theses and Dissertations

Nitrogen (N) derived from fertilizer application in agricultural systems may contribute to significant environmental impacts, including eutrophication of fresh and coastal waters. Rice cutgrass (Leersia oryzoides) can significantly enhance denitrification potential in agricultural ditch sediments, but relationships with known drivers are not well understood. To address this, I examined effects of nitrate (NO3-) availability on dinitrogen gas (N2) and NO3- fluxes seasonally in Chapter 2. Denitrification rates were measured as N2 flux from intact vegetated sediment cores using Membrane Inlet Mass Spectrometry (MIMS). Michaelis-Menten models were developed from observations to mathematically describe N2 fluxes across the spring, summer, and fall …


Soil And Plant Property Differences Among High-Yield Soybean Areas In Arkansas, Taylor Cass Adams Dec 2016

Soil And Plant Property Differences Among High-Yield Soybean Areas In Arkansas, Taylor Cass Adams

Graduate Theses and Dissertations

Continued achievement of soybean [Glycine max (L.) Merr.] yields greater than 6719 kg ha-1 (100 bu ac-1) will depend on decreasing the yield gap, which is contingent on gathering more information regarding the soil physical, chemical, and microbiological environment and the main plant factors contributing to high-yield soybean. Therefore, understanding the main factor differences between high- and average-yield areas may provide insight for making management decisions to increase yields. The objectives of this study were i) to evaluate the effects of region and soil depth on soil property differences between high- and average-soybean-yielding areas, ii) to determine which soil properties …


Liming Characteristics Of A High-Calcium, Dry Flue Gas Desulfurization By-Product And Its Effects On Runoff Water Quality, Jason Richard Burgess-Conforti Dec 2016

Liming Characteristics Of A High-Calcium, Dry Flue Gas Desulfurization By-Product And Its Effects On Runoff Water Quality, Jason Richard Burgess-Conforti

Graduate Theses and Dissertations

In 2013, only 37% of the 32 million Mg of flue gas desulfurization (FGD) by-products generated in the United States were reused beneficially. If FGD by-products could be used as a beneficial soil amendment, millions of megagrams may be diverted away from surface impoundments and landfills. The purpose of this research was to identify the liming characteristics of a high-Ca dry FGD (DFGD) by-product in comparison to a Class-C fly ash (FA) and reagent-grade CaCO3, and to evaluate the effects of land application to a managed grassland on runoff, plant, and soil quality. Liming characteristics were determined by measuring the …


Simple Soil Quality Tests And Organic Management Practices For Orchards In The Intermountain West, Esther Oline Thomsen Dec 2016

Simple Soil Quality Tests And Organic Management Practices For Orchards In The Intermountain West, Esther Oline Thomsen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Soil health is often overlooked as a long-term management strategy as growers face an increasing number of short-term management challenges in the Intermountain West. The costs of inputs are rising and water resources are becoming more limited. Soil with poor health typically requires more amendments and fertlizers to meet crop needs. Soil health tests can help reveal management practices that reduce soil health, as well as those that improve soil health. Practices known to improve soil health are reduced to no tillage, cover crop use- especially legumes, and addition of mulch and other organic materials. Soil health testing is not …


Predicting Post-Fire Change In West Virginia, Usa From Remotely-Sensed Data, Michael Strager P. Strager, Melissa Thomas-Van Gundy, Aaron E. Maxwell Nov 2016

Predicting Post-Fire Change In West Virginia, Usa From Remotely-Sensed Data, Michael Strager P. Strager, Melissa Thomas-Van Gundy, Aaron E. Maxwell

Journal of Geospatial Applications in Natural Resources

Prescribed burning is used in West Virginia, USA to return the important disturbance process of fire to oak and oak-pine forests. Species composition and structure are often the main goals for re-establishing fire with less emphasis on fuel reduction or reducing catastrophic wildfire. In planning prescribed fires land managers could benefit from the ability to predict mortality to overstory trees. In this study, wildfires and prescribed fires in West Virginia were examined to determine if specific landscape and terrain characteristics were associated with patches of high/moderate post-fire change. Using the ensemble machine learning approach of Random Forest, we determined that …


Mapping The Variability Of Soil Quality Indicators In Natural Versus Agricultural Ecosystems, Mary G. Derting Miss Nov 2016

Mapping The Variability Of Soil Quality Indicators In Natural Versus Agricultural Ecosystems, Mary G. Derting Miss

Scholars Week

Traditionally, Kentucky agriculture has focused on crop production and soil fertility while overlooking soil quality and its dependence on land management type. This research attempted to reveal the importance of land management types and their individual effects on physical soil quality indicators. The second objective of this study was to show the variance of physical soil quality indicators across different land managements by using layered maps. Such visual representation of the data along with statistical analysis also showed which soil quality parameters are more sensitive to change in land management type. Land management types included three undisturbed grassland and undisturbed …


Silica Uptake And Release In Live And Decaying Biomass In A Northern Hardwood Forest, Wim Clymans, Daniel J. Conley, John J. Battles, Patrick J. Frings, Mary Margaret Koppers, Gene E. Likens, Chris E. Johnson Nov 2016

Silica Uptake And Release In Live And Decaying Biomass In A Northern Hardwood Forest, Wim Clymans, Daniel J. Conley, John J. Battles, Patrick J. Frings, Mary Margaret Koppers, Gene E. Likens, Chris E. Johnson

Civil and Environmental Engineering - All Scholarship

In terrestrial ecosystems, a large portion (20–80%) of the dissolved Si (DSi) in soil solution has passed through vegetation. While the importance of this “terrestrial Si filter” is generally accepted, few data exist on the pools and fluxes of Si in forest vegetation and the rate of release of Si from decomposing plant tissues. We quantified the pools and fluxes of Si through vegetation and coarse woody debris (CWD) in a northern hardwood forest ecosystem (Watershed 6, W6) at the Hubbard Brook Experimental Forest (HBEF) in New Hampshire, USA. Previous work suggested that the decomposition of CWD may have significantly …


Soil Salinity Increases The Tolerance Of Excessive Sulfur Fumigation Stress In Tomato Plants, Yuping Jiang, Xiaotao Ding, Dong Zhang, Qi Deng, Chih-Li Yu, Suping Zhou, Dafeng Hui Oct 2016

Soil Salinity Increases The Tolerance Of Excessive Sulfur Fumigation Stress In Tomato Plants, Yuping Jiang, Xiaotao Ding, Dong Zhang, Qi Deng, Chih-Li Yu, Suping Zhou, Dafeng Hui

Agricultural and Environmental Sciences Faculty Research

To investigate the responses of plant photosynthesis and chlorophyll fluorescence to excessive sulfur fumigation stress (Sulfur) alleviated by pre-treated salt in the soil (Salt), seedlings of a tomato cultivar (Solanum lycopersicum L. ‘Money Maker’) were exposed to the Sulfur with or without the Salt treatment for 15h. Leaf fresh weight, dry weight, chlorophyll (Chl) content, carotenoid (Car) content, photosynthesis and chlorophyll fluorescence parameters were measured. The results showed that the Sulfur treatment significantly decreased leaf fresh weight, dry weight, Chl and Car contents, net photosynthetic rate (Pn), stomatal conductance (Gs), transpiration rate (Tr), maximum quantum efficiency of photosystem II (PSII) …


A Novel Qtl Associated With Dwarf Bunt Resistance In Idaho 444 Winter Wheat, Jianli Chen, Mary J. Guttieri, Junli Zhang, David Hole, Edward Souza, Blair Goates Sep 2016

A Novel Qtl Associated With Dwarf Bunt Resistance In Idaho 444 Winter Wheat, Jianli Chen, Mary J. Guttieri, Junli Zhang, David Hole, Edward Souza, Blair Goates

Green Canyon Environmental Research Area, Logan Utah

Dwarf bunt [Tilletia controversa J.G. Kühn [as ‘contraversa’], in Rabenhorst, Hedwigia 13: 188 (1874)] is a destructive disease of wheat (Triticum aestivum L.) that reduces grain yield and quality. A number of distinct genes conferring resistance to dwarf bunt have been used by breeding programs for nearly 100 years. However, few markers were identified that can be used in selection of dwarf bunt resistance. A recombinant inbred line (RIL) population derived from the bunt-resistant germplasm, Idaho 444 (IDO444), and the susceptible cultivar, Rio Blanco, was evaluated for phenotypic reaction to dwarf bunt inoculation in four trials in …


Methane Emissions From Global Rice Fields: Magnitude, Spatiotemporal Patterns, And Environmental Controls, Bowen Zhang, Hanqin Tian, Wei Ren, Bo Tao, Chaoqun Lu, Jia Yang, Kamaljit Banger, Shufen Pan Sep 2016

Methane Emissions From Global Rice Fields: Magnitude, Spatiotemporal Patterns, And Environmental Controls, Bowen Zhang, Hanqin Tian, Wei Ren, Bo Tao, Chaoqun Lu, Jia Yang, Kamaljit Banger, Shufen Pan

Plant and Soil Sciences Faculty Publications

Given the importance of the potential positive feedback between methane (CH4) emissions and climate change, it is critical to accurately estimate the magnitude and spatiotemporal patterns of CH4 emissions from global rice fields and better understand the underlying determinants governing the emissions. Here we used a coupled biogeochemical model in combination with satellite-derived contemporary inundation area to quantify the magnitude and spatiotemporal variation of CH4 emissions from global rice fields and attribute the environmental controls of CH4 emissions during 1901–2010. Our study estimated that CH4 emissions from global rice fields varied from 18.3 ± …


Quantifying Peat Carbon Accumulation In Alaska Using A Process-Based Biogeochemistry Model, Sirui Wang, Qianlai Zhuang, Zicheng Yu, Scott Bridgham, Jason K. Keller Aug 2016

Quantifying Peat Carbon Accumulation In Alaska Using A Process-Based Biogeochemistry Model, Sirui Wang, Qianlai Zhuang, Zicheng Yu, Scott Bridgham, Jason K. Keller

Education Faculty Articles and Research

This study uses an integrated modeling framework that couples the dynamics of hydrology, soil thermal regime, and ecosystem carbon and nitrogen to quantify the long-term peat carbon accumulation in Alaska during the Holocene. Modeled hydrology, soil thermal regime, carbon pools and fluxes, and methane emissions are evaluated using observation data at several peatland sites in Minnesota, Alaska, and Canada. The model is then applied for a 10,000 year (15 ka to 5 ka; 1 ka = 1000 cal years before present) simulation at four peatland sites. We find that model simulations match the observed carbon accumulation rates at fen sites …


Modeling PCo2 Variability In The Gulf Of Mexico, Zuo Xue, Ruoying He, Katja Fennel, Wei-Jun Cai, Steven Lohrenz, Wei-Jen Huang, Hanqin Tian, Wei Ren, Zhengchen Zang Aug 2016

Modeling PCo2 Variability In The Gulf Of Mexico, Zuo Xue, Ruoying He, Katja Fennel, Wei-Jun Cai, Steven Lohrenz, Wei-Jen Huang, Hanqin Tian, Wei Ren, Zhengchen Zang

Plant and Soil Sciences Faculty Publications

A three-dimensional coupled physical–biogeochemical model was used to simulate and examine temporal and spatial variability of sea surface pCO2 in the Gulf of Mexico (GoM). The model was driven by realistic atmospheric forcing, open boundary conditions from a data-assimilative global ocean circulation model, and observed freshwater and terrestrial nutrient and carbon input from major rivers. A 7-year model hindcast (2004–2010) was performed and validated against ship measurements. Model results revealed clear seasonality in surface pCO2 and were used to estimate carbon budgets in the Gulf. Based on the average of model simulations, the GoM was a …


Bulletin No. 42: The Mamacoke Conservation Area, Glenn Dreyer, Robert Askins, Scott Peterson Aug 2016

Bulletin No. 42: The Mamacoke Conservation Area, Glenn Dreyer, Robert Askins, Scott Peterson

Bulletins

No abstract provided.


Identifying And Addressing Soil Property Issues Affecting Roadside Vegetation Establishment, Xu Li, Martha Mamo, Walter H. Schacht, Tala Awada, Humberto Blanco-Canqui Aug 2016

Identifying And Addressing Soil Property Issues Affecting Roadside Vegetation Establishment, Xu Li, Martha Mamo, Walter H. Schacht, Tala Awada, Humberto Blanco-Canqui

Nebraska Department of Transportation: Research Reports

Attaining adequate vegetation cover along highways is important for NDOR to comply with EPA’s stormwater regulations. However, low plant cover is a common problem on shoulders (first 16 feet off the pavement) of many highways in Nebraska. The ultimate goal of this study is to identify cost-effective engineering solutions that assure adequate seed beds (i.e., soil conditions) for establishment of selected seeding mixtures. The objectives of this study are to (1) characterize the soil properties along roadsides where vegetation stands have not developed well, and (2) verify the effects of select soil property parameters on plant germination and establishment.

Sampling …


Determination Of Optimum Fall And Spring Nitrogen Fertilizer Rate For Maximizing Grain Yield Of Soft Red Winter Wheat Sown At Variable Planting Dates, Lucas Vasconcelos Vieira Aug 2016

Determination Of Optimum Fall And Spring Nitrogen Fertilizer Rate For Maximizing Grain Yield Of Soft Red Winter Wheat Sown At Variable Planting Dates, Lucas Vasconcelos Vieira

Graduate Theses and Dissertations

An optimum planting date is important for winter wheat nitrogen (N) management as it dramatically changes the growing environment including temperature and moisture, ultimately affecting fertilizer efficiency and grain yield (GY). In Arkansas, high precipitation in the fall often forces farmers to delay planting and current Arkansas recommendations include the application of fall N when soft red winter wheat (SRWW) is sown later than optimum, despite the lack of data supporting this practice. This study evaluated the effect of rate and timing of N application on GY of SRWW sown at variable planting dates in Arkansas. Granular urea was split …


Validation Of N-Star Nitrogen Rate Recommendations And Evaluation Of N-Star Soil Sampling Procedures For Clay Soils In Arkansas, Jarom Thane Davidson Aug 2016

Validation Of N-Star Nitrogen Rate Recommendations And Evaluation Of N-Star Soil Sampling Procedures For Clay Soils In Arkansas, Jarom Thane Davidson

Graduate Theses and Dissertations

The two methods for determining N-fertilizer recommendations for rice (Oryza sativa L.) in Arkansas are the standard N recommendation (SR) based on soil texture, previous crop, and rice cultivar, and the Nitrogen-Soil Test for Rice (N-STaR) which quantifies the potentially mineralizable-N of the soil and provides a site-specific N recommendation. The N-STaR program has recently been developed, and the validation of N-STaR for clay soils is an important step in ensuring that N-STaR predicts correct N-fertilizer rates for rice under a delayed-flood production system. Small-plot trials located across Arkansas compared the N-STaR 95 and 100% relative grain yield (RGY) N …


A R2r3-Myb Transcription Factor Regulates The Flavonol Biosynthetic Pathway In A Traditional Chinese Medicinal Plant, Epimedium Sagittatum, Wenjun Huang, A. B. M. Khaldun, Jianjun Chen, Chanjuan Zhang, Haiyan Lv, Ling Yuan, Ying Wang Jul 2016

A R2r3-Myb Transcription Factor Regulates The Flavonol Biosynthetic Pathway In A Traditional Chinese Medicinal Plant, Epimedium Sagittatum, Wenjun Huang, A. B. M. Khaldun, Jianjun Chen, Chanjuan Zhang, Haiyan Lv, Ling Yuan, Ying Wang

Plant and Soil Sciences Faculty Publications

Flavonols as plant secondary metabolites with vital roles in plant development and defense against UV light, have been demonstrated to be the main bioactive components (BCs) in the genus Epimedium plants, several species of which are used as materials for Herba Epimedii, an important traditional Chinese medicine. The flavonol biosynthetic pathway genes had been already isolated from Epimedium sagittatum, but a R2R3-MYB transcription factor regulating the flavonol synthesis has not been functionally characterized so far in Epimedium plants. In this study, we isolated and characterized the R2R3-MYB transcription factor EsMYBF1 involved in regulation of the flavonol biosynthetic pathway …


Soil Extracellular Enzyme Activities, Soil Carbon And Nitrogen Storage Under Nitrogen Fertilization: A Meta-Analysis, Siyang Jian, Jianwei Li, Ji Chen, Gangsheng Wang, Melanie A. Mayes, Kudjo E. Dzantor, Dafeng Hui, Yiqi Luo Jul 2016

Soil Extracellular Enzyme Activities, Soil Carbon And Nitrogen Storage Under Nitrogen Fertilization: A Meta-Analysis, Siyang Jian, Jianwei Li, Ji Chen, Gangsheng Wang, Melanie A. Mayes, Kudjo E. Dzantor, Dafeng Hui, Yiqi Luo

Agricultural and Environmental Sciences Faculty Research

Nitrogen (N) fertilization affects the rate of soil organic carbon (SOC) decomposition by regulating extracellular enzyme activities (EEA). Extracellular enzymes have not been represented in global biogeochemical models. Understanding the relationships among EEA and SOC, soil N (TN), and soil microbial biomass carbon (MBC) under N fertilization would enable modeling of the influence of EEA on SOC decomposition. Based on 65 published studies, we synthesized the activities of α-1,4-glucosidase (AG), β-1,4-glucosidase (BG), β-d-cellobiosidase (CBH), β-1,4-xylosidase (BX), β-1,4-N-acetyl-glucosaminidase (NAG), leucine amino peptidase (LAP), urease (UREA), acid phosphatase (AP), phenol oxidase (PHO), and peroxidase (PEO) in response to N fertilization. The proxy …


Costimulation Of Soil Glycosidase Activity And Soil Respiration By Nitrogen Addition, Ji Chen, Yiqi Luo, Jianwei Li, Xuhui Zhou, Junji Cao, Rui-Wu Wang, Yunqiang Wang, Shelby Shelton, Zhao Jin, Laura M. Walker, Zhaozhong Feng, Shuli Niu, Wenting Feng, Siyang Jian, Lingyan Zhou Jun 2016

Costimulation Of Soil Glycosidase Activity And Soil Respiration By Nitrogen Addition, Ji Chen, Yiqi Luo, Jianwei Li, Xuhui Zhou, Junji Cao, Rui-Wu Wang, Yunqiang Wang, Shelby Shelton, Zhao Jin, Laura M. Walker, Zhaozhong Feng, Shuli Niu, Wenting Feng, Siyang Jian, Lingyan Zhou

Agricultural and Environmental Sciences Faculty Research

Unprecedented levels of nitrogen (N) have been deposited in ecosystems over the past century, which is expected to have cascading effects on microbially mediated soil respiration (SR). Extracellular enzymes play critical roles on the degradation of soil organic matter, and measurements of their activities are potentially useful indicators of SR. The links between soil extracellular enzymatic activities (EEAs) and SR under N addition, however, have not been established. We therefore conducted a meta-analysis from 62 publications to synthesize the responses of soil EEAs and SR to elevated N. Nitrogen addition significantly increased glycosidase activity (GA) by 13.0%, α-1,4-glucosidase (AG) by …


Cone In Cone Concretions Of The Stanley Group In Southeastern Oklahoma, Kyle B. Ayres May 2016

Cone In Cone Concretions Of The Stanley Group In Southeastern Oklahoma, Kyle B. Ayres

Electronic Theses and Dissertations

Cone in cone concretions found in the Stanley Group of Southeastern Oklahoma have a variety of external and internal attributes which allow diagenetic and theoretical models of formation to be hypothesized. Stanley Group carbonate cone in cone concretions are initially formed in sulfur reducing horizons at shallow burial depths in a poorly circulated possibly deep trough containing siliceous sediments and organic matter. Collected concretions near the town of Smithville, Oklahoma displayed four different external morphologies and four variations of mineral constituents. All concretions contained microscopic cones which initiated diffusion and/or fluid patterns and is an early cementation process that directly …


Compost Land Management And Soil Carbon Sequestration, Kylene A. Hohman May 2016

Compost Land Management And Soil Carbon Sequestration, Kylene A. Hohman

Senior Honors Projects, 2010-2019

Extensive fossil fuel burning has released carbon dioxide into the atmosphere. Under proper ecological conditions plants convert atmospheric carbon dioxide into stable soil organic matter, a natural and efficient means of mitigating climate change. In the symbiotic relationship between mycorrhizae and plants, mycorrhizae provide plants with essential nutrients in exchange for carbon sugars leaked from the plants. Mycorrhizae convert carbon sugars to an exudate called glomalin, a protein that assists in developing soil aggregates composed of sand, silt, and clay. These aggregates, called humus, store carbon for hundreds of years under healthy ecological conditions. Compost prompts soil microbes to aerobically …


11th New World Luminescence Dating Workshop Scientific Program And Abstracts And Field Trip Guide Book, P.R. Hanson, James B. Swinehart, Joseph Mason May 2016

11th New World Luminescence Dating Workshop Scientific Program And Abstracts And Field Trip Guide Book, P.R. Hanson, James B. Swinehart, Joseph Mason

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.