scholarly journals SOIL ERODIBILITY AND SOIL SUSCEPTIBILITY TO EROSION BY WATER IN SHONKOLA MOUNTAINOUS AREA OF SORO DISTRICT, ETHIOPIA

2020 ◽  
Vol 15 (1) ◽  
Author(s):  
Kibemo Detamo Aga
Keyword(s):  
Soil Erosion ◽  
Soil Texture ◽  
Management Strategies ◽  
Fine Sand ◽  
Organic Content ◽  
Mountainous Area ◽  
Soil Erodibility ◽  
Farm Unit ◽  
Almost All ◽  
Clay Percentage

Although the problem of soil erosion is common in all countries, it is one of the more persisting hazards in developing countries like Ethiopia which is a country located in tropic where there is higher precipitation and is vulnerable to almost all forms of environmental degradation which is also resulted from poor resource conservation practices. The main objective of this study is to determine soil erodibility and susceptibility to soil erosion in Shonkola mountainous area, Soro district. To determine soil erodibility and susceptibility to soil erosion, the percentage of primary soil separates (silt, very fine sand, and clay); percentage of organic matter; soil structure classes; and soil permeability were estimated. Soil samples were collected from 56 locations at an average depth of 15 cm to employ soil texture nomograph. Thus, soil erodibility of Shonkola area is determined and mapped to envisage the area that is highly susceptible for soil erosion. The soil erodibility value ranges from 0.01426 to 0.04001. It was found that the soil erodibility increases as organic content decreases, soil texture becomes finer and less permeable, and structure becomes poor. Prediction of soil erodibility and susceptibility to soil erosion is of great importance for soil erosion quantification, using GIS. The farm-unit level identification of soil types and existing specific problems are crucial in planning and implementation of any soil management strategies.

Reinke's Edema: Phonatory Mechanisms and Management Strategies

1997 ◽  
Vol 106 (7) ◽  
pp. 533-543 ◽  
Author(s):  
Steven M. Zeitels ◽  
Glenn W. Bunting ◽  
Robert E. Hillman ◽  
Traci Vaughn
Keyword(s):  
Lamina Propria ◽  
Fundamental Frequency ◽  
Vocal Fold ◽  
Management Strategies ◽  
Vocal Folds ◽  
Vocal Fold Vibration ◽  
Reinke’S Edema ◽  
Subglottal Pressure ◽  
Almost All ◽  
Superficial Lamina

Reinke's edema (RE) has been associated typically with smoking and sometimes with vocal abuse, but aspects of the pathophysiology of RE remain unclear. To gain new insights into phonatory mechanisms associated with RE pathophysiology, weused an integrated battery of objective vocal function tests to analyze 20 patients (19 women) who underwent phonomicrosurgical resection. Preoperative stroboscopic examinations demonstrated that the superficial lamina propria is distended primarily on the superior vocal fold surface. Acoustically, these individuals have an abnormally low average speaking fundamental frequency (123 Hz), and they generate abnormally high average subglottal pressures (9.7 cm H20). The presence of elevated aerodynamic driving pressures reflects difficulties in producing vocal fold vibration that are most likely the result of mass loading associated with RE, and possibly vocal hyperfunction. Furthermore, it is hypothesized that in the environment of chronic glottal mucositis secondary to smoking and reflux, the cephalad force on the vocal folds by the subglottal driving pressure contributes to the superior distention of the superficial lamina propria. Surgical reduction of the volume of the superficial lamina propria resulted in a significant elevation in fundamental frequency (154 Hz) and improvement in perturbation measures. In almost all instances, both the clinician and the patient perceived the voice as improved. However, these patients continued to generate elevated subglottal pressure (probably a sign of persistent hyperfunction) that was accompanied by visually observed supraglottal strain despite the normalsized vocal folds. This finding suggests that persistent hyperfunctional vocal behaviors may contribute to postsurgical RE recurrence if therapeutic strategies are not instituted to modify such behavior.

Detection of oomycide-insensitive Phytophthora isolates in Maryland ornamental nurseries and Mid-Atlantic landscapes provide data for reconsidering management strategies

2021 ◽  
Author(s):  
Justine Beaulieu ◽  
Johanna Del Castillo Munera ◽  
Yilmaz Balci
Keyword(s):  
Growth Rate ◽  
Mycelial Growth ◽  
Management Strategies ◽  
Resistance Management ◽  
Phytophthora Species ◽  
Oak Forests ◽  
Relative Growth ◽  
Off Label ◽  
Potting Media ◽  
Almost All

Five Phytophthora species comprising a total of 243 isolates (77 P. cinnamomi, 23 P. citrophthora, 18 P. multivora, 18 P. pini, and 107 P. plurivora) were screened for sensitivity to mefenoxam, fosetyl-Al, dimethomorph, dimethomorph + ametoctradin and fluoxastrobin using amended agar assays. Mefenoxam-insensitive isolates were detected within P. cinnamomi (4%), P. multivora (11%), and P. plurivora (12%) even at approximately 2.5x the recommended label rate. These isolates were also insensitive to higher (off-label) concentrations of fluoxastrobin. Concentrations of dimethomorph (400 g/mL) and dimethomorph + ametoctradin (100 g/mL) were mostly effective in mycelial growth inhibition, but two P. plurivora isolates were insensitive, suggesting that resistance management is required. All mefenoxam-insensitive isolates were sensitive to fosetyl-Al at the label rate. Surprisingly, the populations of P. cinnamomi from mid-Atlantic oak forests included insensitive isolates. With almost all species, isolates recovered from asymptomatic hosts (e.g., soil/potting media collected of randomly selected asymptomatic hosts) had a significantly greater relative growth rate when compared to isolates recovered from symptomatic hosts (e.g., isolates recovered from lesions or wilted plants). These findings suggest that mefenoxam should no longer be used to manage oomycetes in Maryland ornamental nurseries and that the use of fluoxastrobin should be limited.

Modeling Habitat Suitability and Management Options for Maintaining Round Whitefish (Prosopium cylindraceum) in Adirondack Ponds

2021 ◽  
Author(s):  
Amy Kathleen Conley ◽  
Matthew D. Schlesinger ◽  
James G. Daley ◽  
Lisa K. Holst ◽  
Timothy G. Howard
Keyword(s):  
Species Distribution Model ◽  
Management Strategies ◽  
Distribution Model ◽  
Nonnative Species ◽  
Simulated Population ◽  
Management Options ◽  
The Past ◽  
Almost All ◽  
Reintroduction Success ◽  
Maximum Air Temperature

Habitat loss, acid precipitation, and nonnative species have drastically reduced the number of Adirondack waterbodies occupied by round whitefish (Prosopium cylindraceum). The goal of this study was to 1) increase the probability of reintroduction success by modeling the suitability of ponds for reintroduction and 2) better understand the effects of different rates of pond reclamation. We created a species distribution model that identified 70 waterbodies that were physically similar to occupied ponds. The most influential variables for describing round whitefish habitat included trophic, temperature, and alkalinity classes; waterbody maximum depth; maximum air temperature; and surrounding soil texture and impervious surface. Next, we simulated population dynamics under a variety of treatment scenarios and compared the probability of complete extirpation using a modified Markov model. Under almost all management strategies, and under pressure from nonnative competitors like that observed in the past 30 years, the number of occupied ponds will decline over the next 100 years. However, restoring one pond every 3 years would result in a 99% chance of round whitefish persistence after 100 years.

scholarly journals Characteristics of Soil Erodibility K Value and Its Influencing Factors in the Changyan Watershed, Southwest Hubei, China

Land ◽  
2022 ◽  
Vol 11 (1) ◽  
pp. 134
Author(s):  
Xiaofang Huang ◽  
Lirong Lin ◽  
Shuwen Ding ◽  
Zhengchao Tian ◽  
Xinyuan Zhu ◽  
...  
Keyword(s):  
Land Use ◽  
Soil Erosion ◽  
Spatial Variability ◽  
Influencing Factors ◽  
Soil Type ◽  
Soil Survey ◽  
Purple Soil ◽  
Soil Erodibility ◽  
K Value ◽  
K Factor

Soil erodibility K factor is an important parameter for evaluating soil erosion vulnerability and is required for soil erosion prediction models. It is also necessary for soil and water conservation management. In this study, we investigated the spatial variability characteristics of soil erodibility K factor in a watershed (Changyan watershed with an area of 8.59 km2) of Enshi, southwest of Hubei, China, and evaluated its influencing factors. The soil K values were determined by the EPIC model using the soil survey data across the watershed. Spatial K value prediction was conducted by regression-kriging using geographic data. We also assessed the effects of soil type, land use, and topography on the K value variations. The results showed that soil erodibility K values varied between 0.039–0.052 t·hm2·h/(hm2·MJ·mm) in the watershed with a block-like structure of spatial distribution. The soil erodibility, soil texture, and organic matter content all showed positive spatial autocorrelation. The spatial variability of the K value was related to soil type, land use, and topography. The calcareous soil had the greatest K value on average, followed by the paddy soil, the yellow-brown soil (an alfisol), the purple soil (an inceptisol), and the fluvo-aquic soil (an entisol). The soil K factor showed a negative correlation with the sand content but was positively related to soil silt and clay contents. Forest soils had a greater ability to resist to erosion compared to the cultivated soils. The soil K values increased with increasing slope and showed a decreasing trend with increasing altitude.

scholarly journals Distribution of soil nutrients and erodibility factor under different soil types in an erosion region of Southeast China

PeerJ ◽  
2021 ◽  
Vol 9 ◽  
pp. e11630
Author(s):  
Man Liu ◽  
Guilin Han
Keyword(s):  
Soil Erosion ◽  
Soil Nutrients ◽  
Soil Ph ◽  
Major Elements ◽  
Soil Types ◽  
Soil Erodibility ◽  
Soil Evolution ◽  
Southeast China ◽  
Red Soils ◽  
K Factor

Background Soil erosion can affect the distribution of soil nutrients, which restricts soil productivity. However, it is still a challenge to understand the response of soil nutrients to erosion under different soil types. Methods The distribution of soil nutrients, including soil organic carbon (SOC), soil organic nitrogen (SON), and soil major elements (expressed as Al2O3, CaO, Fe2O3, K2O, Na2O, MgO, TiO2, and SiO2), were analyzed in the profiles from yellow soils, red soils, and lateritic red soils in an erosion region of Southeast China. Soil erodibility K factor calculated on the Erosion Productivity Impact Calculator (EPIC) model was used to indicate erosion risk of surface soils (0∼30 cm depth). The relationships between these soil properties were explored by Spearman’s rank correlation analysis, further to determine the factors that affected the distribution of SOC, SON, and soil major elements under different soil types. Results The K factors in the red soils were significantly lower than those in the yellow soils and significantly higher than those in the lateritic red soils. The SON concentrations in the deep layer of the yellow soils were twice larger than those in the red soils and lateritic red soils, while the SOC concentrations between them were not significantly different. The concentrations of most major elements, except Al2O3 and SiO2, in the yellow soils, were significantly larger than those in the red soils and lateritic red soils. Moreover, the concentrations of major metal elements positively correlated with silt proportions and SiO2 concentrations positively correlated with sand proportions at the 0∼80 cm depth in the yellow soils. Soil major elements depended on both soil evolution and soil erosion in the surface layer of yellow soils. In the yellow soils below the 80 cm depth, soil pH positively correlated with K2O, Na2O, and CaO concentrations, while negatively correlated with Fe2O3 concentrations, which was controlled by the processes of soil evolution. The concentrations of soil major elements did not significantly correlate with soil pH or particle distribution in the red soils and lateritic red soils, likely associated with intricate factors. Conclusions These results suggest that soil nutrients and soil erodibility K factor in the yellow soils were higher than those in the lateritic red soils and red soils. The distribution of soil nutrients is controlled by soil erosion and soil evolution in the erosion region of Southeast China.

scholarly journals Estimation of soil loss using remote sensing and GIS-based universal soil loss equation in northern catchment of Lake Tana Sub-basin, Upper Blue Nile Basin, Northwest Ethiopia

2020 ◽  
Vol 9 (1) ◽  
Author(s):  
Veera Narayana Balabathina ◽  
R. P. Raju ◽  
Wuletaw Mulualem ◽  
Gedefaw Tadele
Keyword(s):  
Remote Sensing ◽  
Land Use ◽  
Soil Erosion ◽  
Soil Loss ◽  
Erosion Rate ◽  
Soil Erodibility ◽  
Lake Tana ◽  
Erosion Rates ◽  
Soil Erosion Rate ◽  
Soil Loss Equation

Abstract Background Soil erosion is one of the major environmental challenges and has a significant impact on potential land productivity and food security in many highland regions of Ethiopia. Quantifying and identifying the spatial patterns of soil erosion is important for management. The present study aims to estimate soil erosion by water in the Northern catchment of Lake Tana basin in the NW highlands of Ethiopia. The estimations are based on available data through the application of the Universal Soil Loss Equation integrated with Geographic Information System and remote sensing technologies. The study further explored the effects of land use and land cover, topography, soil erodibility, and drainage density on soil erosion rate in the catchment. Results The total estimated soil loss in the catchment was 1,705,370 tons per year and the mean erosion rate was 37.89 t ha−1 year−1, with a standard deviation of 59.2 t ha−1 year−1. The average annual soil erosion rare for the sub-catchments Derma, Megech, Gumara, Garno, and Gabi Kura were estimated at 46.8, 40.9, 30.9, 30.0, and 29.7 t ha−1 year−1, respectively. Based on estimated erosion rates in the catchment, the grid cells were divided into five different erosion severity classes: very low, low, moderate, high and extreme. The soil erosion severity map showed about 58.9% of the area was in very low erosion potential (0–1 t ha−1 year−1) that contributes only 1.1% of the total soil loss, while 12.4% of the areas (36,617 ha) were in high and extreme erosion potential with erosion rates of 10 t ha−1 year−1 or more that contributed about 82.1% of the total soil loss in the catchment which should be a high priority. Areas with high to extreme erosion severity classes were mostly found in Megech, Gumero and Garno sub-catchments. Results of Multiple linear regression analysis showed a relationship between soil erosion rate (A) and USLE factors that soil erosion rate was most sensitive to the topographic factor (LS) followed by the support practice (P), soil erodibility (K), crop management (C) and rainfall erosivity factor (R). Barenland showed the most severe erosion, followed by croplands and plantation forests in the catchment. Conclusions Use of the erosion severity classes coupled with various individual factors can help to understand the primary processes affecting erosion and spatial patterns in the catchment. This could be used for the site-specific implementation of effective soil conservation practices and land use plans targeted in erosion-prone locations to control soil erosion.

scholarly journals Managing Uncertainty in Chronic Illness From Patient Perspectives

2020 ◽  
Vol 2 (1) ◽  
Author(s):  
Amanda Brown ◽  
Susan Hayden ◽  
Karen Klingman ◽  
Leslie C Hussey
Keyword(s):  
Chronic Illness ◽  
Phenomenological Study ◽  
Management Strategies ◽  
Healthcare Providers ◽  
The United States ◽  
Healthcare Team ◽  
Control And Prevention ◽  
Qualitative Phenomenological ◽  
Almost All ◽  
Qualitative Phenomenological Study

Chronic illness is an increasing concern in the United States as the Centers for Disease Control and Prevention reports that 50% of adults have at least one chronic illness. When individuals must adjust to chronic illness, they may experience uncertainty regarding the illness, prognosis, and symptoms. The purpose of this qualitative, phenomenological study was to explore the management strategies of uncertainty in chronic illness from patients’ perspectives. Merle Mishel’s uncertainty in illness theory was the framework used to explore the lives of individuals diagnosed and living with chronic illness. In-depth interviews were conducted with eight individuals who have chronic disease. Results revealed themes that individuals with chronic illness do experience uncertainty and that it impacts almost all aspects of their lives. Some of the themes identified were chronic illness, uncertainty, impact of uncertainty on daily living, coping or managing uncertainty, and communication from the healthcare team about uncertainty. The individuals expressed changes in daily activities and retraining their minds to accept their new normal. This study offers coping and management strategies that healthcare professionals can implement into treatment plans to improve the quality of life for individuals with uncertainty in chronic illness. The information produced from this study will aid healthcare providers in understanding the need to address the uncertainty at diagnoses and offer ways to assist patients in coping and managing uncertainty

Environmental controls in Pacific Northwest intertidal marsh plant communities

1983 ◽  
Vol 61 (4) ◽  
pp. 1105-1116 ◽  
Author(s):  
Kern Ewing
Keyword(s):  
Redox Potential ◽  
Pacific Northwest ◽  
Soil Texture ◽  
Puget Sound ◽  
Principal Component ◽  
Organic Content ◽  
Mode Analysis ◽  
Soil Redox Potential ◽  
Soil Redox ◽  
Environmental Controls

Relationships between environmental variables and species distribution were studied in a brackish intertidal marsh formed by the Skagit River as it enters the Puget Sound bay system in Washington. Transects were established which covered the range of environmental variation in the marsh. A grid of environmental measuring stations provided information on soil texture, organic content of soil fines, macroorganic material in the soil, soil temperatures, interstitial soil water salinity, soil redox potential, and site elevation. Binary discriminant analysis, a nonparametric method using species presence–absence data, was used to construct standardized residual matrices. Principal component analysis of standardized residuals (Q mode) indicated that salinity and soil texture were strongly correlated with the first factor generated, elevation with the second, and soil redox potential with the third. The factors explained, respectively, 48, 21, and 14% of the variance in the residuals matrix. From R-mode analysis, eight community types were derived: three dominated by Carex lyngbyei, two by Scirpus americanus, one by Scirpus maritimus, and two which are highly diverse.

Advances in techniques to assess soil erodibility

2021 ◽  
pp. 175-214
Author(s):  
R. J. Rickson ◽  
◽  
E. Dowdeswell Downey ◽  
G. Alegbeleye ◽  
S. E. Cooper ◽  
...  
Keyword(s):  
Soil Erosion ◽  
Test Procedure ◽  
Aggregate Stability ◽  
Analytical Techniques ◽  
Soil Biology ◽  
Soil Erodibility ◽  
Erosion Rates ◽  
Erosion Processes ◽  
Assessment Techniques ◽  
Soil Erosion By Water

Soil erodibility is the susceptibility of soil to the erosive forces of rainsplash, runoff and wind. It is a significant factor in determining present and future soil erosion rates. Focusing on soil erosion by water, this chapter shows that erodibility is determined by static and dynamic soil properties that control a range of sub-processes affecting soil erosion, but there is no standardised test procedure, making comparison of erodibility assessment techniques and their results challenging. Most researchers agree that aggregate stability is the best indicator of soil erodibility. Selection of techniques to measure aggregate stability need to consider the type of disruptive forces and breakdown processes to which field aggregates are subjected. New indices must incorporate spatial and temporal variabilities in erodibility; the different erosion processes operating; the impact of climate change; and the role of soil biology. New analytical techniques such as computer aided tomography show promise in considering soil erodibility as a dynamic continuum operating over 3 dimensions.

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