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2017

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Articles 91 - 120 of 120

Full-Text Articles in Soil Science

Fescue Tolerance Testing, Monty Kerley Jan 2017

Fescue Tolerance Testing, Monty Kerley

Kentucky Grazing Conference

Fescue toxicosis is characterized by clinical symptoms such as vasoconstriction, immunosuppression, and poor thermoregulation. Fescue toxins bind to membrane receptors of cells that control constriction of blood through capillaries responsible for heat dissipation. When cattle consume toxic tall fescue, they lose ability to move blood to their skin where heat can be lost to the environment. As they lose this ability they become more prone to heat stress. In the winter, this lack of blood flow leads to other clinical symptoms, such as fescue foot and loss of tail switch, that occur from restricted blood flow.


Research Update: Beef Cattle Management Considerations For Grazing Tall Fescue, Frank Ireland Jan 2017

Research Update: Beef Cattle Management Considerations For Grazing Tall Fescue, Frank Ireland

Kentucky Grazing Conference

It has been reported that 8 million beef cattle graze an estimated 35 million acres of endophyte-infected tall fescue in the United States with the majority of tall fescue being produced in the Midwest and southeastern regions of the United States. In the presence of the endophytic fungus, ergot alkaloids are present that when consumed by beef cattle results in decreased animal performance as measured in reduced weight gains, lower body condition scores, decreased conception rates, rough hair coats and the inability to regulate body temperatures. It has been estimated that this loss in animal performance accounts for a $600 …


In Defense Of Soil Health, Allen R. Williams Jan 2017

In Defense Of Soil Health, Allen R. Williams

Kentucky Grazing Conference

Soil health is a hot topic today in sustainable agriculture circles and is even becoming more popular in conventional agriculture. However, the term is often thrown around loosely, and sometimes the meaning gets muddled.


Foreword And Conference Information [2017], Matt Bunger Jan 2017

Foreword And Conference Information [2017], Matt Bunger

Kentucky Grazing Conference

This is the front matter of the proceedings.


Closing The Water Budget In An Experimental Urban Watershed: A Comparative Assessment Of Methods For Measuring Evapotranspiration, Leana M. Weissberg, Gaboury Benoit Jan 2017

Closing The Water Budget In An Experimental Urban Watershed: A Comparative Assessment Of Methods For Measuring Evapotranspiration, Leana M. Weissberg, Gaboury Benoit

Yale Day of Data

No abstract provided.


Assessing The Risk Of Carbon Dioxide Emissions From Blue Carbon Ecosystems, Catherine E. Lovelock, Trisha Brooke Atwood, Jeff Baldock, Carlos M. Duarte, Sharyn Hickey, Paul S. Lavery, Pere Masque, Peter I. Macreadie, Aurora M. Ricart, Oscar Serrano, Andy Steven Jan 2017

Assessing The Risk Of Carbon Dioxide Emissions From Blue Carbon Ecosystems, Catherine E. Lovelock, Trisha Brooke Atwood, Jeff Baldock, Carlos M. Duarte, Sharyn Hickey, Paul S. Lavery, Pere Masque, Peter I. Macreadie, Aurora M. Ricart, Oscar Serrano, Andy Steven

Watershed Sciences Faculty Publications

“Blue carbon” ecosystems, which include tidal marshes, mangrove forests, and seagrass meadows, have large stocks of organic carbon (Corg) in their soils. These carbon stocks are vulnerable to decomposition and – if degraded – can be released to the atmosphere in the form of CO2. We present a framework to help assess the relative risk of CO2 emissions from degraded soils, thereby supporting inclusion of soil Corg into blue carbon projects and establishing a means to prioritize management for their carbon values. Assessing the risk of CO2 emissions after various kinds of disturbances …


The Optical Trapezoid Model: A Novel Approach To Remote Sensing Of Soil Moisture Applied To Sentinel-2 And Landsat-8 Observations, Morteza Sadeghi, Ebrahim Babaeian, Markus Tuller, Scott B. Jones Jan 2017

The Optical Trapezoid Model: A Novel Approach To Remote Sensing Of Soil Moisture Applied To Sentinel-2 And Landsat-8 Observations, Morteza Sadeghi, Ebrahim Babaeian, Markus Tuller, Scott B. Jones

Plants, Soils, and Climate Faculty Publications

The “trapezoid” or “triangle” model constitutes the most popular approach to remote sensing (RS) of surface soil moisture based on coupled thermal (i.e., land surface temperature) and optical RS observations. The model, hereinafter referred to as Thermal-Optical TRAapezoid Model (TOTRAM), is based on interpretation of the pixel distribution within the land surface temperature - vegetation index (LST-VI) space. TOTRAM suffers from two inherent limitations. It is not applicable to satellites that do not provide thermal data (e.g., Sentinel-2) and it requires parameterization for each individual observation date. To overcome these restrictions we propose a novel OPtical TRApezoid Model (OPTRAM), which …


Rock Magnetic Investigation Of The Michigan Basin Soils And Sediments Overlying The Oil-Bearing Silurian Pinnacle Reefs, Jake Tresnak Jan 2017

Rock Magnetic Investigation Of The Michigan Basin Soils And Sediments Overlying The Oil-Bearing Silurian Pinnacle Reefs, Jake Tresnak

Dissertations, Master's Theses and Master's Reports

A relationship between the hydrocarbon migration and magnetic properties of near-surface sediments was investigated from several hundreds of samples collected over the hydrocarbon-bearing Silurian pinnacle reef belt of the Michigan Basin. The collected samples were investigated using several rock magnetic methods and optical microscopy. The investigation has not revealed a straightforward relationship between the magnetic susceptibility and hydrocarbon reservoirs within the reef belt; both anomalously high and low susceptibility values were observed. The elevated values are associated with newly formed magnetite in the form of spheroidal grains produced by hydrocarbon-related diagenesis while the extremely low susceptibilities may reflect dissolution of …


Effects Of Biochar Treatment Of Municipal Biosolids And Horse Manure On Quality Of Runoff From Fescue Plots, Rachel Williams, Dwayne R. Edwards Jan 2017

Effects Of Biochar Treatment Of Municipal Biosolids And Horse Manure On Quality Of Runoff From Fescue Plots, Rachel Williams, Dwayne R. Edwards

Biosystems and Agricultural Engineering Faculty Publications

Land-applied horse manure and municipal biosolids can increase nutrient and bacteria concentrations in runoff. Biochar has been demonstrated to have beneficial impacts on nutrient retention and runoff quality when used to treat other land-applied organic soil amendments (e.g., poultry manure). The objective of this study was to evaluate the effects of biochar addition to horse manure and municipal biosolids on runoff concentrations of nutrients and fecal coliforms. Biochar was added at 5% to 8% (wet basis) to horse manure and biosolids that were applied to 2.4 m x 6.1 m fescue plots followed by application of simulated rainfall (102 mm …


2016 Nebraska Water Leaders Academy - Final Report, Mark E. Burbach, Connie Reimers-Hild Jan 2017

2016 Nebraska Water Leaders Academy - Final Report, Mark E. Burbach, Connie Reimers-Hild

Conservation and Survey Division: Faculty and Staff Publications

The effective management of Nebraska’s water resources is evermore challenged by variations in weather, climate, technology, socioeconomic policies, and regulation. Anthropogenic climate change, declining water tables and stream flows, increasing demands on freshwater, aging water infrastructure, fiscal constraints, and impacts on aquatic organisms are particularly imminent challenges in Nebraska and around the world (Pahl-Wostl et al., 2013; Pittock et al., 2008; USACE, 2010). Sustaining freshwater ecosystem services in the face of emerging environmental threats presents an immense societal dilemma worldwide (Pittock et al., 2013; Rockström et al., 2009, Millenium Ecosystem Assessment, 2005). The rapidly changing conditions of water resources in …


Field Investigation Of An Active Landslide In Kentucky: A Framework To Correlate Electrical Data And Shear Strength, Matthew M. Crawford, L. Sebastian Bryson Jan 2017

Field Investigation Of An Active Landslide In Kentucky: A Framework To Correlate Electrical Data And Shear Strength, Matthew M. Crawford, L. Sebastian Bryson

Report of Investigations--KGS

Landslide hazard assessments are best accomplished by a multidisciplinary approach that connects geologic processes with geotechnical behavior. Tools to accomplish this in the field include geologic characterization, hydrologic monitoring, and geophysical surveys, and in the laboratory, soil-strength testing. Volumetric water content, soil-water potential (suction), local rainfall, and in situ electrical conductivity were measured at a shallow colluvial landslide in Kentucky. Surface electrical-resistivity surveys were also conducted to support interpretations of depth to failure, lithologic differences, and changes in moisture content over time. Correlations of hydrologic data with electrical measurements and shear strength indicate that observed changes in the degree of …


Impacts Of Crop Residue And Cover Crops On Soil Hydrological Properties, Soil Water Storage And Water Use Efficiency Of Soybean Crop, Kopila Subedi-Chalise Jan 2017

Impacts Of Crop Residue And Cover Crops On Soil Hydrological Properties, Soil Water Storage And Water Use Efficiency Of Soybean Crop, Kopila Subedi-Chalise

Electronic Theses and Dissertations

Cover crops and crop residue play a multifunctional role in improving soil hydrological properties, soil water storage and water use efficiency (WUE). This study was conducted to better understand the role of crop residue and cover crop on soil properties and soil water dynamics. The study was conducted at the USDA-ARS North Central Agricultural Research Laboratory, located in Brookings, South Dakota. Two residue removal treatments that include low residue removal (LRR) and high residue removal (HRR) were established in 2000 with randomized complete block design under no-till corn (Zea mays L.) and soybean (Glycine max L.) rotation. In 2005, cover …


Response Of Soil Properties To 23-25 Years Of Diverse Crop Rotations And Tillage Systems In South Dakota, Usa, Abdullah H. Alhameid Jan 2017

Response Of Soil Properties To 23-25 Years Of Diverse Crop Rotations And Tillage Systems In South Dakota, Usa, Abdullah H. Alhameid

Electronic Theses and Dissertations

Diverse cropping systems and no-till (NT) are beneficial in improving soil organic carbon (SOC) and other soils properties. The present study was conducted to evaluate the interactions and impacts of long-term tillage and diverse crop rotation systems on soil quality indicators that include a range of soil chemical, physical, hydrological, and microbial properties. The study was established in 1991 at Beresford, South Dakota and included three crop rotation systems [2-yr; maize (Zea mays L.)-soybean (Glycine max L.), 3-yr; maize-soybean-oat (Avena sativa L.), and 4-yr; maize-soybean-oat-wheat (Triticum aestivum L.)] managed under two tillage systems (NT and CT; conventional- tillage). Soil sampling …


Soil Response To Cropping Sequences And Grazing Under Integrated Crop-Livestock System, Hanxiao Feng Jan 2017

Soil Response To Cropping Sequences And Grazing Under Integrated Crop-Livestock System, Hanxiao Feng

Electronic Theses and Dissertations

Integrated crop-livestock system (ICLS) is helpful in diversifying a farm for improving its long-term sustainability and economic benefits. In the United States, the ICLS has been increasing in recent years because of its economic and environmental benefits. However, the impacts of ICLS on soil quality is not well documented in North Dakota. The objective of our study is to assess the impacts of cropping sequences and cattle grazing on the selected soil properties in the crop diversity and livestock integration practice. This study site was established in 2010 at the Dickinson Research Extension Center, Dickinson, North Dakota. The study design …


Impacts Of Integrated Crop-Livestock System On Soil Surface Greenhouse Gas Fluxes At A Farm Scale In South Dakota, Brant Douville Jan 2017

Impacts Of Integrated Crop-Livestock System On Soil Surface Greenhouse Gas Fluxes At A Farm Scale In South Dakota, Brant Douville

Electronic Theses and Dissertations

Grazing and cover crops (CC) can impact soil nutrient cycling but may increase the greenhouse gas (GHG) emissions from soils. However, little is known about their impacts on soil properties and soil surface GHG emissions in an integrated crop-livestock system (ICLS) in South Dakota, USA. The present study was conducted at a farm scale at the Research Farm of South Dakota State University, Brookings, South Dakota, to assess the impact of cover crops and grazing on soil pH, electrical conductivity (EC), and bulk density (BD), and soil surface carbon dioxide (CO2), methane (CH4), and nitrous oxide …


Impacts Of Landscape Position And Nitrogen Fertilizer On Soils, Carbon And Nitrogen Leaching, And Greenhouse Gas Fluxes From Switchgrass Production In South Dakota, Liming Lai Jan 2017

Impacts Of Landscape Position And Nitrogen Fertilizer On Soils, Carbon And Nitrogen Leaching, And Greenhouse Gas Fluxes From Switchgrass Production In South Dakota, Liming Lai

Electronic Theses and Dissertations

Switchgrass (Panicum virgatum L.) production for biofuels has potential economic values. It can also improve soil properties and perform better under marginal lands than the other major biomass crops. However, little is known about its potential ecological impacts assessed in terms of soils, water, and air quality in the northern Great Plains region of United States of America. The objectives of this study were to (i) evaluate the impacts of nitrogen fertilization rate (N rate) and landscape position on soil pH, soil organic carbon (SOC), total nitrogen (TN), bulk density (ρb), and phosphorus (P) in switchgrass field; (ii) assess …


Interactive Effects Of Cover Crops, Invertebrate Communities And Soil Health In Corn Production Systems, Claire Lacanne Jan 2017

Interactive Effects Of Cover Crops, Invertebrate Communities And Soil Health In Corn Production Systems, Claire Lacanne

Electronic Theses and Dissertations

The adoption of regenerative farming practices is gaining traction, but the costs and benefits are not often considered on a systems level. Encouraging biodiversity and soil health is the goal of many agricultural practices used in regenerative farming; regenerative systems employ practices which abide by the two main principles of increasing biodiversity and decreasing disturbance, with the goal of encouraging ecosystem functioning to minimize inputs and maximize the productivity of a farm. I examined the management of corn (Zea mays) fields across four states in the Upper Midwest region of the United States. Regenerative systems in this study …


Quantifying Ephemeral Gully Erosion With Photogrammetry Surveying, C. B. Weerasekara, A. Y. Shechukov Jan 2017

Quantifying Ephemeral Gully Erosion With Photogrammetry Surveying, C. B. Weerasekara, A. Y. Shechukov

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Nebraska Statewide Groundwater-Level Monitoring Report 2016, Aaron R. Young, Mark E. Burbach, Leslie M. Howard, Michele M. Waszgis, R. Matthew Joeckel, Sue Olafsen Lackey Jan 2017

Nebraska Statewide Groundwater-Level Monitoring Report 2016, Aaron R. Young, Mark E. Burbach, Leslie M. Howard, Michele M. Waszgis, R. Matthew Joeckel, Sue Olafsen Lackey

Conservation and Survey Division: Faculty and Staff Publications

The term “groundwater” has come to be all but synonymous with Nebraska. Nearly three-quarters of the volume of the High Plains aquifer lies beneath the State, and groundwater maintains our streams, our ecosystems, our people, and our vitally important agricultural economy. Although Nebraska’s total groundwater resource is vast, it is also quite vulnerable to changes induced by natural processes and by humankind, necessitating a long-term commitment to wise management through informed decision making. Monitoring, studying, and reporting are the essential basis for such management and, ultimately, for meeting the myriad challenges presented by change.

The personnel of the Conservation and …


Short-Term Effects Of Nutrients On A Barrier Island Grassland Community, Ashley Moulton Jan 2017

Short-Term Effects Of Nutrients On A Barrier Island Grassland Community, Ashley Moulton

Theses and Dissertations

Increased nutrient availability globally has the potential to affect community functional composition of plants in nutrient limited environments, such as coastal grassland systems. Stability of these systems are threatened worldwide by urbanization, as well as effects of sea level rise and increased frequency and intensity of storms, and atmospheric N deposition, associated with climate change. Annual net primary productivity (ANPP), species composition, and functional traits (community weighted specific leaf area (CWSLA), leaf area index (LAI), growth form and photosynthetic pathway) were measured across four treatments to assess multiple resource limitation of nitrogen (N) and phosphorus (P) and functional community response …


Effects Of Silvopasture Establishment On Aqueous And Gaseous Soil N Losses At The University Of New Hampshire Organic Dairy Research Farm, Kathryn Ann Slebodnik Jan 2017

Effects Of Silvopasture Establishment On Aqueous And Gaseous Soil N Losses At The University Of New Hampshire Organic Dairy Research Farm, Kathryn Ann Slebodnik

Honors Theses and Capstones

The expansion of local agriculture in the New England region is putting increased pressure on farmers to expand their arable land base. While clear-cutting is a traditional method of converting forested land to agriculture, it is known for having adverse ecological impacts. To minimize these impacts, farmers can create a silvopasture which incorporates a portion of the original forest canopy into pastures or crop fields. This study evaluates the impact of land-use changes for agriculture on soil nitrogen (N) retention. In particular, this study investigates the differences in soil N turnover, gaseous loss, and aqueous loss among an established forest, …


Data Potential Of Archaeological Deposits At The Chelan Station Site, Matthew J. Breidenthal Jan 2017

Data Potential Of Archaeological Deposits At The Chelan Station Site, Matthew J. Breidenthal

All Master's Theses

The Chelan Station Site (45CH782/783), located along the Rocky Reach of the Columbia River, includes lithic and faunal artifacts buried beneath volcanic tephra from Mt. Mazama (6,830 BP). Artifacts were inadvertently discovered in buried soils within a secondary alluvial terrace during construction of a pipeline to supply water to the Beebe Springs Fish Hatchery. This thesis stems from participation in original field work and includes the author’s own models of early land forms and site formation. The study reviews the construction monitoring and archaeological testing of both sites, and documents the archaeological data potential early occupations of the vicinity. The …


Using Thermal Infrared Imagery To Estimate Soil Hydraulic Parameters: A Novel Approach, Matthew B. Thomas Jan 2017

Using Thermal Infrared Imagery To Estimate Soil Hydraulic Parameters: A Novel Approach, Matthew B. Thomas

Undergraduate Theses, Professional Papers, and Capstone Artifacts

In this study, skin temperature measured with a thermal infrared (TIR) camera was used to estimate soil hydraulic parameters. These physical properties that control how soils transport and retain water are notoriously difficult to measure in the field due to spatial variability. Laboratory experiments were set up to record surface skin temperature response in a clean soil column using a TIR camera after an artificial wetting event. An array of thermocouples, a net radiometer, heat flux sensor and weather station were used to constrain the TIR data and the energy budget during the experiment. The soil column surface was then …


A Method For Reflectance Index Wavelength Selection From Moisture-Controlled Soil And Crop Residue Samples, Ali Hamidisepehr, Michael P. Sama, Aaron P. Turner, Ole O. Wendroth Jan 2017

A Method For Reflectance Index Wavelength Selection From Moisture-Controlled Soil And Crop Residue Samples, Ali Hamidisepehr, Michael P. Sama, Aaron P. Turner, Ole O. Wendroth

Biosystems and Agricultural Engineering Faculty Publications

Reflectance indices are a method for reducing the dimensionality of spectral measurements used to quantify material properties. Choosing the optimal wavelengths for developing an index based on a given material and property of interest is made difficult by the large number of wavelengths typically available to choose from and the lack of homogeneity when remotely sensing agricultural materials. This study aimed to determine the feasibility of using a low-cost method for sensing the moisture content of background materials in traditional crop remote sensing. Moisture-controlled soil and wheat stalk residue samples were measured at varying heights using a reflectance probe connected …


Water–Soil–Vegetation Dynamic Interactions In Changing Climate, Xixi Wang, Xuefeng Chu, Tingxi Liu, Xiangju Cheng, Rich Whittecar Jan 2017

Water–Soil–Vegetation Dynamic Interactions In Changing Climate, Xixi Wang, Xuefeng Chu, Tingxi Liu, Xiangju Cheng, Rich Whittecar

Civil & Environmental Engineering Faculty Publications

Previous studies of land degradation, topsoil erosion, and hydrologic alteration typically focus on these subjects individually, missing important interrelationships among these important aspects of the Earth's system. However, an understanding of water–soil–vegetation dynamic interactions is needed to develop practical and effective solutions to sustain the globe's eco-environment and grassland agriculture, which depends on grasses, legumes, and other fodder or soil-building crops. This special issue is intended to be a platform for a discussion of the relevant scientific findings based on experimental and/or modeling studies. Its 12 peer-reviewed articles present data, novel analysis/modeling approaches, and convincing results of water–soil–vegetation interactions under …


Analysis Of Microbial Diversity In Disturbed Soil, Tyler G. Sanda Jan 2017

Analysis Of Microbial Diversity In Disturbed Soil, Tyler G. Sanda

Williams Honors College, Honors Research Projects

This paper uses the composition and abundance of microbial species to analyze soil recovery in disturbed land. Surface mining disturbs ecological communities throughout the world. As organizations seek to reclaim these disturbed lands, a proper analysis of recovery is needed. In previous studies, recovery of disturbed land was limited to surface examinations, which do not characterize the possible unseen devastating effects of the subsoil. Soil microorganisms are extremely sensitive to environmental changes such as strip mining. It is proposed that these microorganisms may serve as better indicators of recovery post disturbance. Our analysis indicates microbial recovery, however it may not …


Soil Hydraulic Property Estimation Under Major Land-Uses In The Shawnee Hills, Trinity Joseph Baker Jan 2017

Soil Hydraulic Property Estimation Under Major Land-Uses In The Shawnee Hills, Trinity Joseph Baker

Theses and Dissertations--Plant and Soil Sciences

The ability to map soil moisture is becoming more important with changing climates and modeling these effects depends on reliable estimations of hydrologic soil properties under different land managements. This study: 1) tests the application of existing soil hydraulic property estimation methods against in-situ values of six catenas under two covers (forest and grass); 2) validate Random Forest Algorithm (RF) estimates informed from the six catenas on two separate catenas; 3) identify Rapid Carbon Assessment (RaCA) sites within the Shawnee Hills Region that represent different land-uses (Crop, Conservation Reserve Program (CRP), Forest, and Pasture); 4) apply RF learning tree informed …


Evaluating Soil Physical And Chemical Properties Following Addition Of Non-Composted Spent Coffee And Tea For Athletic Fields, Shuang Zhou Jan 2017

Evaluating Soil Physical And Chemical Properties Following Addition Of Non-Composted Spent Coffee And Tea For Athletic Fields, Shuang Zhou

Theses and Dissertations--Plant and Soil Sciences

Physical and chemical properties of non-composted spent coffee (CF) and tea (T) suggest they may have applications as soil amendments for improving poor soils. Studies were conducted to determine 1) the effect of amendments on grass growth and soil properties, 2) the effect of incorporation versus surface application of amendments on soil properties, and 3) the effect of amendment application frequency on grass growth and soil properties. In the first study, amendments were mixed with sand and planted to bermudagrass. Treatments included CF, T, and peat moss (PM) mixed with sand, and 100% sand as a control. In the second …


Soil Erosion Risk Factors And The Impacts Of Diversification On Organic Strawberry Farms Along California’S Central Coast, Kay Sterner Jan 2017

Soil Erosion Risk Factors And The Impacts Of Diversification On Organic Strawberry Farms Along California’S Central Coast, Kay Sterner

Pomona Senior Theses

Soil erosion is a major issue that threatens to undermine our current system of agriculture. Due to the fact that this system is in turn the number one cause of erosion, agricultural practices in the United States need to be rethought. This study explores how traditional ideas of erosion risks are related to observed erosion on organic strawberry farms along California’s Central Coast. In addition, diversified farming systems are addressed as a possible solution for the current unsustainability of our farming practices. The data from this research suggest that diversity of crops on farms could be linked to less soil …


Upscaling Stem To Community-Level Transpiration For Two Sand-Fixing Plants: Salix Gordejevii And Caragana Microphylla, Limin Duan, Yang Li, Xue Yan, Tingxi Liu, Xixi Wang Jan 2017

Upscaling Stem To Community-Level Transpiration For Two Sand-Fixing Plants: Salix Gordejevii And Caragana Microphylla, Limin Duan, Yang Li, Xue Yan, Tingxi Liu, Xixi Wang

Civil & Environmental Engineering Faculty Publications

The information on transpiration is vital for sustaining fragile ecosystem in arid/semiarid environment, including the Horqin Sandy Land (HSL) located in northeast China. However, such information is scarce in existing literature. The objectives of this study were to: (1) measure sap flow of selected individual stems of two sand-fixing plants, namely Salix gordejevii and Caragana microphylla, in HSL; and (2) upscale the measured stem-level sap flow for estimating the community-level transpiration. The measurements were done from 1 May to 30 September 2015 (i.e., during the growing season). The upscaling function was developed to have one dependent variable, namely sap …