Modeling the effects of rainfall intensity and deep chiseling on infiltration and runoff within DRAINMOD for alluvial soils

Accurate hydrologic models are needed to aid engineers and researchers design, install and evaluate efficient and cost-effective agricultural water management systems to reduce risks associated with food production, and to reduce soil erosion and water pollution. One model used for the alluvial soils of Louisiana is DRAINMOD. This model does not accurately predict infiltration and runoff for the crusting-prone alluvial soils of Louisiana. The main goal of this study was to modify the current DRAINMOD model to incorporate the effects of rainfall intensity and deep chiseling to improve its estimation of infiltration and surface runoff. The second goal was to use information gained from the modified DRAINMOD model to assess how long farmers and environmentalists benefit from a particular deep chiseling operation and determine optimum deep chiseling frequency for given climatic conditions. A methodology for using a five-minute rainfall time increment subroutine within DRAINMOD was developed. Field experiments yielded an initial vertical saturated hydraulic conductivity of 2.0 cm/hr, a final vertical saturated hydraulic conductivity of 0.50 cm/hr and exponent of 0.03 cm-1 for model calibration. Deep chiseling modifications resulted in the DRAINMOD-STMAX, DRAINMOD-Ks and the combined DRAINMOD-Ks-STMAX models. DRAINMOD-STMAX, DRAINMOD-Ks and DRAINMOD-Ks-STMAX model improved surface runoff prediction by 57%, 73%, and 82% respectively in1995/96 season and by 27%, 45%, and 62% respectively in 1996/7 season. Using DRAINMOD-Ks-STMAX model, deep chiseling a Commerce silt loam soil increased infiltration by 9.4% and reduced runoff by 19.7% in 1995/96 season and by 5.7% and 19.2% respectively in 1996/97 season. All benefits resulting from deep chiseling were lost after 115 cm of rainfall since deep chiseling. Farmers should deep chisel once every year when annual rainfall is greater than 100 cm and once every two to three years when annual rainfall is less than 100 cm. Sixty percent or more of the maximum deep chiseling benefits had been lost by planting time; therefore, farmers need to deep chisel their fields just before planting. Further work is needed in the field to determine other factors affecting variation of Ks, to validate the DRAINMOD-STMAX, DRAINMOD-Ks and DRAINMOD-Ks-STMAX models, and to incorporate rainfall intensity subroutine

DISPROPORTIONALITY IN SPECIAL EDUCATION: SPECIAL EDUCATION TEACHERS’ PERCEPTIONS ABOUT DISPROPORTIONALITY OF AFRICAN AMERICAN STUDENTS IN SPECIAL EDUCATION

African American students experience school failure in many different ways and a disproportional number are placed into special education. Disproportionality in special education is an issue that needs to be investigated as it poses a societal concern, because the school and post-school outcomes of students receiving special education are less desirable than peers not receiving special education services. Researchers and educational leaders suggest reasons for ethnic disproportionality in special education, including cultural and historical background of African American students, parental and family perceptions towards educators and special education, special education evaluation procedures used to screen students for special needs, early identification of African American youths and intervention they receive, and perceptions of school personnel towards African American youth. To explore why perceptions of school personnel contribute to the disproportional numbers of special education placements, I undertook and used qualitative case study methodology to explore African American special education teachers perceptions about cultural misunderstanding as a possible cause for overrepresentation of African American students in special education. I interviewed six African American special educators. The findings strongly suggest cultural misunderstanding exists and it contributes to the disproportionality of African American students in special education. Cultural misunderstanding occurs when educators of African American students fail to recognize underlying factors manifest in the cultural behaviors of African American students. Cultural behaviors are those deemed inappropriate in a learning environment. Cultural misunderstanding impacts more upon African American male youths than females. Implications of these results are also discussed

Annual baseflow variations as influenced by climate variability and agricultural land use change in the Missouri River Basin

The Missouri River system has a large water storage capacity, where baseflow plays an important role. Understanding historical baseflow characteristics with respect to climate and land use impacts is essential for effective planning and management of water resources in the Missouri River Basin (MORB). This study evaluated statistical trends in baseflow and precipitation for 99 MORB minimally disturbed watersheds during 1950–2014. Elasticity of baseflow to climate variability and agricultural land use change were quantified for the 99 studied watersheds. Baseflow was derived from daily streamflow records with a recursive digital filter method. The results showed that baseflow varied between 38 and 80% (0 and 331 mm/year) of total streamflow with an average of 60%, indicating that more than half of streamflow in the MORB is derived from baseflow. The trend analysis revealed that precipitation increased during the study period in 78 out of 99 watersheds, leading to 1–3.9% noticeable increase in baseflow for 68 of 99 watersheds. Although the changes in baseflow obtained in this study were a result of the combined effects of climate and land use change across the basin, upward trends in baseflow generally coincide with increased precipitation and agricultural land use trends in the basin. Agricultural land use increase mostly led to a 0–5.7% decrease in annual baseflow in the basin, except toward east of the basin where baseflow mostly increased with agricultural land use increase (0.1–2.0%). In general, a 1% increase in precipitation and a 1% increase in agricultural land use resulted in 1.5% increase and 0.2% decrease in baseflow, respectively, during the study period. These results are entirely dependent on the quality of data used; however, they provide useful insight into the relative influence of climate and land use change on baseflow conditions in the Great Plains region of the USA

Nitrogen and Phosphorus Eutrophication in Marine Ecosystems

Nitrogen (N) and phosphorus (P) eutrophication in marine ecosystems is a global problem. Marine eutrophication has a negative impact on food security, ecosystem health and economy through disruptions in tourism, fisheries and health industries. Both N and P have known point and non-point sources. Control of point sources has been easier than non-point sources particularly agricultural sources for both N and P as well as fossil fuel combustion for N, which remains a major challenge. Implementing mitigation strategies for N has been reported to be effective for P mitigation; however, the converse is not true due to mobility and volatility of N. Excessive N and P cause algae blooms, anoxic conditions, and ocean acidification with these conditions leading to dead zones, fish kill, toxin production, altered plant species diversity, food web disruption, tourism disruption and health issues. Management of N and P pollution includes reduction of leaching from farms through crop selection, timely and precise application of fertilizer and building artificial wetlands, proper management of animal waste, reduction of fossil fuel N emission, mitigating N and P from urban sources and restoration of aquatic ecosystem. Mitigation measures need to focus on dual nutrient strategy for successful N and P reduction

The Relationship between Teacher Characteristics and Information and Communication Technology (ICT) Integration in Public Secondary Schools in Nakuru Town Sub-County, Kenya

This study sought to examine the relationship between teacher characteristics and ICT integration in public secondary schools in Nakuru Town Sub-county. The objectives of the study were: To establish the relationship between attitude and ICT integration; to establish the relationship between motivation and ICT integration, and to determine the overall effect of teacher characteristics on ICT integration. This study employed a descriptive analysis. The data was analyzed quantitatively. The study adopted a descriptive research design. Primary data was collected using a self-administered questionnaire. The relationship between teacher characteristics and ICT integration was tested statistically using Pearson Moments Correlation. Relationships between teacher characteristics and ICT integration in public secondary schools was determined at the alpha level of p<0.05. To describe the various elements of teacher characteristics on overall ICT integration, descriptive analysis (percentages) was done. Data was presented using tables. The purposive sampling design was used in the study where one Headteacher, one Head of ICT Department and one ICT teacher were purposively sampled from each of the 22 public secondary schools yielding a sample size of 66 teachers.The study established that teachers’ characteristics affect ICT integration positively. The study is beneficial to policy makers when developing teacher programs; it also helps teachers to see that intervention programs can influence their instructional behaviors; and it also provides evidence to researchers that teacher beliefs can be challenged.The study thus recommends that policymakers should incorporate the actual use of ICT when developing teacher programs. Considering the influence of the teacher characteristics on classroom use of ICT, professional teacher development should be aware of the direct impact of these variables, especially the role of teacher ICT motivation. Keywords: Teacher characteristics, ICT integration, Attitude, Motivation

The Effect of Teacher Characteristics on Information and Communication Technology (ICT) Integration in Public Secondary Schools in Nakuru Town Sub-County, Kenya

This study sought to examine the effect of teacher characteristics on ICT integration in public secondary schools in Nakuru Town Sub-county, Kenya. The objectives of the study were: To establish the effect of teacher educational beliefs on ICT integration; to establish the effect of self-efficacy on ICT integration. The study adopted a descriptive research design. The effect of teacher characteristics on ICT integration was tested statistically using Pearson Moments Correlation. The effect of teacher characteristics on ICT integration in public secondary schools was determined at the alpha level of p<0.05. To describe the various elements of teacher characteristics on overall ICT integration, descriptive analysis (percentages) was done. Data was presented using tables. Purposive sampling design was used in the study where one Head teacher, one Head of ICT Department and one ICT teacher were purposively sampled from each of the 22 public secondary schools yielding a sample size of 66 teachers.The findings of this study was that teacher characteristics positively affect ICT integration. The study is beneficial to policy makers when developing teacher programs; it also helps teachers to see that intervention programs can influence their instructional behaviors; and it also provides evidence to researchers that teacher beliefs can be challenged.The study thus recommends that policymakers should incorporate the actual use of ICT when developing teacher programs. Considering the influence of the teacher characteristics on classroom use of ICT, professional teacher development should be aware of the direct impact of these variables, especially the role of teacher ICT motivation. Keywords: Teacher characteristics, ICT integration, Educational beliefs, Self-efficacy

Effect of Mobile Bank Innovation and Cost of Implementation on Financial Performance of Commercial Banks in Kenya (A Case Study of a Commercial Bank in Embu County)

Financial institutions in Kenya are in the process of significant transformation. The force behind the transformation of these institutions is innovation in information technology, rapid development of information technology has made banking tasks more efficient and cheaper. Banks are now increasingly choosing mobile platforms for innovative payment models and commerce capabilities. The general objective of the study was to analyze the effect of mobile banking innovation on the financial performance of Commercial Banks in Kenya. The specific objective was to establish the effect of mobile banking innovation financial performance of commercial banks in Kenya and to ascertain the extent to which the costs of implementing and maintaining mobile banking service influence the financial performance of Commercial Banks This study adopted descriptive research design. Target population was a total of 120 respondents from a commercial bank of study in Embu. Stratified random sampling method was used to pick a sample size of 36 respondents. The study collected both primary and secondary data. Primary data was collected using questionnaires. Secondary data was collected from annual reports of the bank. The collected data was analyzed using descriptive statistic especially frequency and percentage presentation. The findings were presented using Graphs and Frequency Distribution Tables. The findings established that new innovation on mobile banking products and costs of implementing and maintaining mobile banking service influence the profitability and creation of shareholder wealth in the bank. This study concludes that new mobile banking product innovation significantly influence financial performance of commercial banks in Keny

Simulation of Daily Flow Pathways, Tile-Drain Nitrate Concentrations, and Soil-Nitrogen Dynamics Using SWAT

Tile drainage significantly alters flow and nutrient pathways and reliable simulation at this scale is needed for effective planning of nutrient reduction strategies. The Soil and Water Assessment Tool (SWAT) has been widely utilized for prediction of flow and nutrient loads, but few applications have evaluated the model\u27s ability to simulate pathway-specific flow components or nitrate-nitrogen (NO3-N) concentrations in tile-drained watersheds at the daily time step. The objectives of this study were to develop and calibrate SWAT models for small, tile-drained watersheds, evaluate model performance for simulation of flow components and NO3-N concentration at daily intervals, and evaluate simulated soil-nitrogen dynamics. Model evaluation revealed that it is possible to meet accepted performance criteria for simulation of monthly total flow, subsurface flow (SSF), and NO3-N loads while obtaining daily surface runoff (SURQ), SSF, and NO3-N concentrations that are not satisfactory. This limits model utility for simulating best management practices (BMPs) and compliance with water quality standards. Although SWAT simulates the soil N-cycle and most predicted fluxes were within ranges reported in agronomic studies, improvements to algorithms for soil-N processes are needed. Variability in N fluxes is extreme and better parameterization and constraint, through use of more detailed agronomic data, would also improve NO3-N simulation in SWAT. Editor\u27s note: This paper is part of the featured series on SWAT Applications for Emerging Hydrologic and Water Quality Challenges. See the February 2017 issue for the introduction and background to the series

Assessment of three long-term gridded climate products for hydro-climatic simulations in tropical river basins

10.3390/w9030229Water (Switzerland)9322