scholarly journals Advances and Challenging Issues in Subsurface Drainage Module Technology and BIOECODS: A Review

2018 ◽  
Vol 203 ◽  
pp. 07005 ◽  
Author(s):  
Abdurrasheed Sa'id Abdurrasheed ◽  
Khamaruzaman Wan Yusof ◽  
Husna Bt Takaijudin ◽  
Aminuddin Ab. Ghani ◽  
Muhammad Mujahid Muhammad ◽  
...  
Keyword(s):  
Drainage System ◽  
Numerical Data ◽  
Subsurface Drainage ◽  
Infiltration Capacity ◽  
Sustainable Solutions ◽  
Ecologically Sustainable ◽  
The Impact ◽  
Flow Attenuation ◽  
Permeability Rate ◽  
Over Time

Subsurface drainage modules are important components of the Bio-ecological Drainage System (BIOECODS) which is a system designed to manage stormwater quantity and quality using constructed grass swales, subsurface modules, dry and wet ponds. BIOECODS is gradually gaining attention as one of the most ecologically sustainable solutions to the frequent flash floods in Malaysia and the rest of the world with a focus on the impact of the subsurface modules to the effectiveness of the system. Nearly two decades of post-construction research in the BIOECODS technology, there is need to review findings and areas of improvement in the system. Thus, this study highlighted the key advances and challenges in these subsurface drainage modules through an extensive review of related literature. From the study, more work is required on the hydraulic characteristics, flow attenuation and direct validation methods between field, laboratory, and numerical data. Also, there is concern over the loss of efficiency during the design life especially the infiltration capacity of the module, the state of the geotextile and hydronet over time. It is recommended for the sake of higher performance, that there should be an onsite methodology to assess the permeability, rate of clogging and condition of the geotextile as well as the hydronet over time.

scholarly journals Straight to Low-Sinuosity Drainage Systems in a Variscan-Type Orogen—Constraints from Tectonics, Lithology and Climate

Minerals ◽  
2021 ◽  
Vol 11 (9) ◽  
pp. 933
Author(s):  
Harald G. Dill ◽  
Andrei Buzatu ◽  
Sorin-Ionut Balaban
Keyword(s):  
Chemical Weathering ◽  
Current Model ◽  
Drainage System ◽  
Numerical Data ◽  
Structural Features ◽  
Acute Angle ◽  
Drainage Systems ◽  
Starting Point ◽  
Bedrock Lithology ◽  
The Impact

A holistic-modular approach has been taken to study the evolution of three straight to low-sinuosity drainage systems (=SSS) in an uplifted basement block of the Central European Variscides. The development of the SSS is described by means of a quadripartite model. (1) The geological framework of the SSS: Forming the lithological and structural features in the bedrock as a result of different temperature, pressure and dynamic-metamorphic processes. (2) Prestage of SSS: Forming the paleo-landscape with a stable fluvial regime as a starting point for the SSS. (3) Proto-SSS: Transition into the metastable fluvial regime of the SSS. (4) Modern SSS: Operation of the metastable fluvial regime Tectonics plays a dual role. Late Paleozoic fold tectonic creates the basis for the studied SSS and has a guiding effect on the development of morphotectonic units during the Neogene and Quaternary. Late Cenozoic fault tectonics triggered the SSS to incise into the Paleozoic basement. The change in the bedrock lithology has an impact on the fluvial and colluvial sediments as well as their landforms. The latter reflects a conspicuous modification: straight drainage system ⇒ higher sinuosity and paired terraces ⇒ hillwash plains. Climate change has an indirect effect controlling via the bedrock the intensity of mechanical and chemical weathering. The impact on the development of the SSS can be assessed as follows: Tectonics >> climate ≅ bedrock lithology. The three parameters cause a facies zonation: (1) wide-and-shallow valley (Miocene), (2) wide-angle V-shaped valley (Plio-Pleistocene), (3) acute-angle V-shaped valley (Pleistocene), (4) V-shaped to U-shaped valleys (Pleistocene-Holocene). Numerical data relevant for the hydrographic studies of the SSS are determined in each reference area: (1) Quantification of fluvial and colluvial deposits along the drainage system, (2) slope angles, (3) degree of sinuosity as a function of river facies, (4) grain size distribution, (5) grain morphological categorization, (6) grain orientation (“situmetry”), (7) channel density, (8) channel/floodplain ratios. Thermodynamic computations (Eh, pH, concentration of solubles) are made to constrain the paleoclimatic regime during formation of the SSS. The current model of the SSS is restricted in its application to the basement of the Variscan-Type orogens, to an intermediate crustal maturity state.

scholarly journals EVALUATING HYDRAULIC PROPERTIES OF SOILS: A MANAGEMENT STRATEGY TOWARDS FIGHTING THE 21ST CENTURY FLOOD DISASTER

2020 ◽  
pp. 32-36
Author(s):  
M. S. Adiaha ◽  
E. E. Oku
Keyword(s):  
Soil Profile ◽  
Water Conservation ◽  
Overland Flow ◽  
Drainage System ◽  
Flood Disaster ◽  
Infiltration Capacity ◽  
Dry Land ◽  
Advance Drainage ◽  
The Impact ◽  
Water Holding

The continual destruction of the environment due to anthropogenic and natural factors has played a role in increasing global flood disaster, acting like a hindrance in meeting the target of global sustainability. Flood has been looked at as an overland flow of water into land which is naturally dry after filling-up of natural open and close water holding bodies. The impact caused by flood disaster has been recorded and include death of humans and animals, apart from the massive destruction of properties and infrastructures, thereby limiting human development. Looking at land and water as a scare and unrenewable natural resources, then it follows that effective management of land and water resources is one way a society can maximize it economic growth and development. Studying the flux of fluid especially water into the soil profile is a great approach in investigating a soil towards the tendency for flooding. Infiltration is the key to soil water conservation and management. The ability of the soil to act as a sponge in-other to cut-down the raising cases of loss of lives and property with associated impact due to flood disaster lies on its infiltration capacity. The study evaluated the strength of soils of University of Abuja Flood meadows to absorb hydrological shock as flood. Outcome of the study revealed that dry land of University of Abuja flood meadow is able to absorbed reasonable quantity of water as flood, with coefficient of variability value of (CV=12%) for the hydraulic conductivity of the site. While bulk density of the area was found to be (2.30 g cm-3) and Porosity of (8%). Conclusion of the study states that most of the sites investigated have a weak hydrological potential in regards to adsorbing and transporting of the water down the soil profile, hence the area should be put to vegetation cover to reduce the flooding impact, alongside an advance drainage system in the area.  

scholarly journals Evolution of the Materials and Methods Used for Subsurface Drainage of Agricultural Lands from Antiquity to the Present

Water ◽  
2020 ◽  
Vol 12 (6) ◽  
pp. 1767 ◽  
Author(s):  
Stavros I. Yannopoulos ◽  
Mark E. Grismer ◽  
Khaled M. Bali ◽  
Andreas N. Angelakis
Keyword(s):  
Agricultural Production ◽  
Crop Yields ◽  
Drainage System ◽  
Implementation Process ◽  
Subsurface Drainage ◽  
Agricultural Drainage ◽  
Land Productivity ◽  
Technological Advances ◽  
Poorly Drained Soils ◽  
Over Time

Agricultural drainage plays an important role worldwide in food production and conservation of soil resources, while safeguarding investments in agricultural production and irrigation projects. It can improve crop yields and land productivity, especially on poorly drained soils and in cases of prolonged waterlogging. Both the subsurface drainage materials and the installation techniques used have a long history dating to prehistoric times. Over time, new subsurface drainage materials, installation techniques and modernized equipment were being developed continuously to take advantage of technological advances provided through research and development, while the planning and organization of the implementation process were improved. Today’s new materials and improved installation methods can offer solutions to problems still unsolved, while sometimes creating new ones. This paper considers the evolution of basic subsurface drainage materials and their installation techniques as they developed and adapted over time as well as possible future trends in drainage system design and application.

scholarly journals Approximation of subsurface drainage discharge by De Zeeuw-Hellinga theory and its verification in heavy soils of fluvial landscape of the Cerhovice brook

2009 ◽  
Vol 4 (No. 1) ◽  
pp. 28-38
Author(s):  
J. Štibinger
Keyword(s):  
Water Conservation ◽  
Drainage System ◽  
Field Measurements ◽  
Subsurface Drainage ◽  
Analytical Approximation ◽  
Real Field ◽  
Design Parameters ◽  
Engineering Practice ◽  
Drainage Systems ◽  
The Impact

The subsurface drainage discharge is one of the most important indicators of the impact of the drainage systems on the water management. The procedure adopted in this study is based on the application of the De Zeeuw-Hellinga theory to derive the final expression for the estimation of the value of the subsurface drainage discharge. A simple analytical approximation of the Bussinesq’s Equation was used to verify theoretically the validity of the De Zeeuw-Hellinga assumptions and to confirm the correctness of other corresponding processes. The formulas describing the subsurface drainage discharge were derived in the conditions of the unsteady state subsurface flow to drains. These conditions included the approximately horizontal impervious layer and the Dupuit’s assumptions and Darcy’s law. No recharge to the groundwater table was realised during the drainage testing. The applicability of the De Zeeuw-Hellinga formula and the accuracy of the analytical approximation of the subsurface drainage discharge by the Bussinesq’s Equation were verified by the real field measurements on the heavy soils of the experimental watershed area of the Research Institute for Soil and Water Conservation (RISWC) Prague-Zbraslav, Czech Republic. The same data were successfully used also for the confirmation of the accuracy of the method for the derivation of a simple analytical approximation of the subsurface total drainage quantity. It was demonstrated that this approximation of the subsurface drainage discharge by De Zeeuw-Hellinga theory could satisfactorily serve in the area of water engineering practice as an elementary tool for the immediate estimation of the values of the subsurface drainage discharges from the pipe drainage systems in the saturated porous environment. The advantage of this approximation is particularly the minimum amount of the input data, e.g. the basic soil hydrology data and drainage system basic design parameters. The sphere of the use of the De Zeeuw-Hellinga equations is certainly very wide. The verifications of the field test results and measurements demonstrated that the possibilities of applications and their perceived benefits to the user can be fulfilled.

The Therapist’s Reaction to a Patient’s Suicide

Crisis ◽  
2011 ◽  
Vol 32 (2) ◽  
pp. 99-105 ◽  
Author(s):  
Friedrich Martin Wurst ◽  
Isabella Kunz ◽  
Gregory Skipper ◽  
Manfred Wolfersdorf ◽  
Karl H. Beine ◽  
...  
Keyword(s):  
Emotional Responses ◽  
Well Being ◽  
Emotional Reaction ◽  
Emotional Reactions ◽  
Analog Scale ◽  
General Hospitals ◽  
Item Questionnaire ◽  
Retrospective Nature ◽  
The Impact ◽  
Over Time

Background: A substantial proportion of therapists experience the loss of a patient to suicide at some point during their professional life. Aims: To assess (1) the impact of a patient’s suicide on therapists distress and well-being over time, (2) which factors contribute to the reaction, and (3) which subgroup might need special interventions in the aftermath of suicide. Methods: A 63-item questionnaire was sent to all 185 Psychiatric Clinics at General Hospitals in Germany. The emotional reaction of therapists to patient’s suicide was measured immediately, after 2 weeks, and after 6 months. Results: Three out of ten therapists suffer from severe distress after a patients’ suicide. The item “overall distress” immediately after the suicide predicts emotional reactions and changes in behavior. The emotional responses immediately after the suicide explained 43.5% of the variance of total distress in a regression analysis. Limitations: The retrospective nature of the study is its primary limitation. Conclusions: Our data suggest that identifying the severely distressed subgroup could be done using a visual analog scale for overall distress. As a consequence, more specific and intensified help could be provided to these professionals.

The impact of price on preference consistency over time

2011 ◽  
Author(s):  
Ki Yeon Lee ◽  
Min Zhao
Keyword(s):  
The Impact ◽  
Over Time

Has Aid Helped in Pakistan?

1997 ◽  
Vol 36 (4II) ◽  
pp. 947-957 ◽  
Author(s):  
Shahrukh Rafi Khan
Keyword(s):  
Economic Growth ◽  
Negative Impact ◽  
Negative Association ◽  
Causal Impact ◽  
The Impact ◽  
Over Time

This paper has a two-fold objective: first, to examine the terms on which Pakistan receives aid and whether its debt situation is sustainable, and second, to examine the impact of aid and debt on economic growth. It is found that there is little encouraging that can be said about how the terms on which Pakistan has received aid over time have changed, and its current debt situation is not sustainable. Also reported is the analysis done elsewhere which shows that aid has a negative (Granger) causal impact on GDP, and aid has a robust negative impact on economic growth after controlling for supplyside shocks. We provide various reasons for this negative association.

The Role of Vascular Aging in Atherosclerotic Plaque Development and Vulnerability

2019 ◽  
Vol 25 (29) ◽  
pp. 3098-3111 ◽  
Author(s):  
Luca Liberale ◽  
Giovanni G. Camici
Keyword(s):  
Atherosclerotic Plaque ◽  
Molecular Mechanisms ◽  
Driving Forces ◽  
Plaque Burden ◽  
Vascular Aging ◽  
Age Related ◽  
Plaque Development ◽  
Increased Risk ◽  
The Impact ◽  
Over Time

Background: The ongoing demographical shift is leading to an unprecedented aging of the population. As a consequence, the prevalence of age-related diseases, such as atherosclerosis and its thrombotic complications is set to increase in the near future. Endothelial dysfunction and vascular stiffening characterize arterial aging and set the stage for the development of cardiovascular diseases. Atherosclerotic plaques evolve over time, the extent to which these changes might affect their stability and predispose to sudden complications remains to be determined. Recent advances in imaging technology will allow for longitudinal prospective studies following the progression of plaque burden aimed at better characterizing changes over time associated with plaque stability or rupture. Oxidative stress and inflammation, firmly established driving forces of age-related CV dysfunction, also play an important role in atherosclerotic plaque destabilization and rupture. Several genes involved in lifespan determination are known regulator of redox cellular balance and pre-clinical evidence underlines their pathophysiological roles in age-related cardiovascular dysfunction and atherosclerosis. Objective: The aim of this narrative review is to examine the impact of aging on arterial function and atherosclerotic plaque development. Furthermore, we report how molecular mechanisms of vascular aging might regulate age-related plaque modifications and how this may help to identify novel therapeutic targets to attenuate the increased risk of CV disease in elderly people.

Sign in / Sign up

Export Citation Format

Share Document