Soil and Water Conservation Engineering

Spatially nonuniform runoff reduces the water quality performance of constant-
width filter strips. A geographic information system (GIS)-based tool was developed
and tested that employs terrain analysis to account for spatially nonuniform runoff and produce
more effective filter strip designs. The computer program, AgBufferBuilder, runs with
ArcGIS versions 10.0 and 10.1 (Esri, Redlands, California) and uses digital elevation models
to identify detailed spatial patterns of overland runoff to field margins. The tool then sizes filter
dimensions according to those patterns using buffer area ratio relationships. The resulting
design is larger along segments where more runoff flows and smaller along segments where
runoff is less and delivers a constant level of trapping efficiency around the field margin for
sediment and sediment-bound pollutants. The tool also can estimate trapping efficiency of
existing filter strips or hypothetical configurations. In a validation test, estimates of sediment
trapping efficiency using the tool’s assessment function compared closely to measurements
taken on large field plots in central Iowa. Using AgBufferBuilder, designs developed for a
sample of fields in the midwestern United States were estimated to trap nearly double the
sediment, on average, during a design storm than constant-width configurations having equivalent
total filter area. AgBufferBuilder can be used to bolster environmental performance of
filter strips where runoff is spatially nonuniform. The AgBufferBuilder tool is publicly available
on the websites http://www2.ca.uky.edu/BufferBuilder and http://nac.unl.edu/tools/ AgBufferBuilder.

In some conditions, soils are submitted at the same time to thermal and hydraulic solicitations. Under these variations, the unsaturated hydraulic conductivity (ku) of the soil evolves. The determination of the time evolution of the water content profile inside the samples is necessary to calculate ku but its establishing is complex. In this study, a Magnetic Resonance Imaging method named Single Point Imaging was used. First, a calibration curve connects the MRI signal to the water content of samples prepared at various water contents and densities. Then the method is applied on clayey sample (argillite) submitted to two drying tests of at least 4 days at 20 or 40°C. The imposed hygrometry was 33%. Finally, the Instantaneous Profile Method was used to determine ku values from water content profiles. This method was successful in recording the impact of the heating on the drying kinetics.

Water hyacinth, water lettuce and morning glory plants were examined for their ability to remove nutrients from aquaculture wastewater at four Hydraulic Retention Times. During the experiment, the aquatic plants grew rapidly and appeared healthy with green colour. The initial pollutant load of the aquaculture effluents were analyzed in the laboratory  to be 12.60mgL-1, 2010mgL-1, 108 mgL-1, 0.05 mgL-1, 0.34 mgL-1, 0.56 mgL-1, 0.40 mgL-1, 6.40 ,4020µs cm-1 for TSS, TDS, COD, Ammonium, Nitrite, Nitrate, Orthophosphate respectively. The TSS, TDS COD, NH4+-N, NO2--N,NO3--N and PO43- - P reductions ranged from 21.4 to 48.0%, from 71.1 to 89.5%, from 55.9 to 76.0%, from 49.6 to 90.6%, from 34.5 to 54.4% and from 64.5 to 76.8%, respectively. Water hyacinth was found to be the most efficient followed by water lettuce and morning glory. At hydraulic retention time of 28days, water hyacinth was able to reduce pollutant load of TDS by 98%, TSS  by 63%, NO2-  by 85%,  PO43- by 88% with slight variation with NO3- by 79% where water lettuce was reduced by 91%. Conversely water hyacinth and water lettuce reduced NH4+ at same rate of 80%. Also water hyacinth reduced COD by 4% as against morning glory by 69%.  By and large, the reductions increased with longer retention times and were highest in the hydroponic units containing water hyacinth followed by hydroponic units containing water lettuce and morning glory.

THIS IS NATURE SIGNALING THE END OF DUALITY 
THIS IS HUGE - CHANGE THE ENTIRETY OF CREATION - NO DUALITY ANYWHERE.
IT IS VERY CLEARLY A PREDETERMINED ADVANCEMENT OF HUMAN CONSCIOUSNESS - THIS BUBBLE IS TOO WELL DESIGNED - EUPHORIA CANCELS KARMA

Gandaki province has the good potentiality of hydroelectricity generation with existing twenty-nine hydroelectricity projects. Since the Province is rich in water resources, analysis of watersheds needs to be done for management, planning and identification of water as well as natural resources. GIS offers integration of spatial and no spatial data to understand and analyze the watershed processes and helps in drawing a plan for integrated watershed development and management. The Digital Elevation Model (DEM) available on the NASA-Earth data has been taken as a primary data for morphometric analysis of watershed in Gandaki Province using QGIS. Delineation of watershed was conducted from a DEM by computing the flow direction and using it in the Watershed tool. Necessary fill sink correction was made before proceeding to delineation. A raster representing the direction of flow was created using Flow Direction tool to determine contributing area. Flow accumulation raster was created f...

The need to increase food production and improve the quality of our environment has prompted a search for materials to control wind and water erosion. This paper is a review of research and development associated with application, methods, and amounts of mulch types-crop residues, chemical soil stabilizers, and feedlot wastes (manure)-required to control wind erosion. An effective wind erosion control treatment is one that can resist a 38.0 m/s wind as measured at 15.2 m. Mulching has becomes an important practice in modern field production. Mulch paper reduces the application of chemical fertilizer and herbicide, weed control and maintain the land temperature. This article reviews the published research on mulches and discusses the opportunities that they solving the problem in agriculture.

ئه‌ندازه‌ی دیمه‌ن یا ئه‌ندازه‌ی سه‌وزایی، لقێكی ته‌لارسازیه‌ و ئامانجی بریتیه‌ له‌ رێكخستنی رووبه‌ری شار و شوێنی نیشته‌جێبوون له‌گه‌ڵ سروشت له‌ پێناو سوودی جه‌سته‌یی و ده‌روونی مرۆڤ.
ئه‌ندازه‌ی دیمه‌ن،  ژینگه‌ی ده‌ره‌وه‌ رێكده‌خات به‌ لاسایی كردنه‌وه‌ی سروشت و تێكه‌ڵكێشی هونه‌ر و جوانكاری ده‌كات له‌سه‌ر بنه‌مای په‌یوه‌ندی سروشت و ژیانی مرۆڤ.

Thysanolaena maxima (Roxb.) O. Ktze. is a species belonging to the Poaceae or Graminae family. The grass is prized for its inflorescences which are processed into soft brooms. Recently, there is a growing interest on its biology and uses. However, literature on this species is still scanty. In this paper, its importance in industry, medicine, agriculture, phytoremediation, bioengineering, climate change adaptation and its other relevant uses were reviewed from available literature primarily to promote it as a multipurpose crop that must be given attention by R&D institutions for the optimization of its potential.

Erosi aktual berdasarkan nilai RKLSCP yang memiliki nilai lebih tinggi dari erosi yang dapat ditoleransi (TSL) memerlukan tindakan konservasi, begitu sebaliknya. Tindakan konservasi harus melihat aspek sosial, ekonomi, dan kondisi riil di lapang sehingga teknik konservasi tanah dan air dapat dilakukan seoptimal mungkin.

The research focused on the management of stormwater and sewage generated in a
developed urban area - Federal University of Technology, Akure, Ondo State, Nigeria. This involved the design of sanitary sewers, stormwater collection networks and a central sewage treatment plant. The total estimate of the wastewater generated from various locations was 5.067 million litres per day based on the population of approximately 26,131. The existing sewage disposal system in use in the institution was the septic tank-soakaway arrangement for individual buildings. The design of the sanitary sewers and stormwater collection networks are based on the principles of hydraulics. The results obtained were used to analyze and design the drains and pipe sizes for the open channels and the closed conduits respectively. The size of the drains for stormwater collection networks was designed with the assumption of 0.75 and 1 meter width. Also, calculations were made for square drain (depth equals width)
to be able to select practicable sizes. For optimum size solution, pipe size of 100 mm was found to be suitable for wastewater conveyance from the office areas. The sizes of pipes calculated for flows from residential quarters are too small, hence available commercial pipe sizes were selected. Wastewater samples were collected at various locations and were determined through laboratory tests to ascertain the concentrations of significant physical, chemical and biological content of the wastewater for proper selection of appropriate treatment processes. A BOD concentration of 350 mg/l and 353 mg/l obtained for residential and office areas respectively translated to high pollution load requires treatment before ultimate discharge into the receiving stream. The proposed sewage treatment plant was sited
at the lowest topographical level, far enough from the office and residential quarters. This would allow flow by gravity from the various points. The sewage treatment plant components selected include screen chamber, grit chamber, skimming tank and rectangular/circular primary settling/sedimentation tank (PST), which are designed to optimal dimensions.

The need to irrigate farms/gardens by a method that will replace the unavailable, accessibility and cost
of importing drip irrigation materials led to the design and construction of a localized drip irrigation
system. In this study, a localized drip irrigation system was designed, constructed and installed. The
system was designed to deliver water required by the crop intermittently (i.e. specific amount at a
specific interval of time). The system was constructed exclusively from locally available materials. The
emitter was punched using 1mm diameter needle on a 20m long lateral. It was designed for tomato
crop (Lycopersicum esculentum spp) with irrigation interval of five days. The test of the system shows
that the water application was adequate; the pump used for the operation of water lifting was 2" water
pump. The result of system’s test revealed a nice outcome by wetting the area situated on the lateral at
60cm to one another at almost same application rate. Emitter blockage which is the common problem
with drip system of irrigation was fairly controlled by an improvised secondary filter made from hand
washing water base. The end of each lateral was pegged to avoid lateral overlapping one another and
as well to keep the lateral firm to the ground. The drip system designed can irrigate 240m2 of an area
with 660 tomato crop stands. The use of this system will surely help in alleviating poverty and easing
labour task and drudgery in farming activities especially in rural communities.

The study encompassed the following trials:
A) Characterization of rainfall in Erbil. The objective was to simulate all
the physical characteristic of natural rainfall as accurately as possible by
rainfall simulator during this study and in future.
B) Calculation of water requirement for some selected winter crops in Erbil
using four different schemes, namely, Blaney-Criddle, modified Blenney
Criddle, Kharufa and Penman monteith.
C) Testing the effect of various soil treatments, namely, control, compaction,
paraffin, spoiled oil, crude oil and sodium chloride salt on runoff inducement
after packing three soils with contrasting soil textures in perforated trays.
The tests were carried out under simulated rainfall with two intensities (10
and 20 mm h-1) using three lands slopes (5, 10 and 15%). Each combination
treatment was replicated thrice. The response variables included runoff
volume, soil loss, EC and pH of the collected runoff water.
D) Examining the effectiveness of different soil treatments in the field under
actual rainfall events via establishing twelve runoff plots (5 m by 2 m ) with
6% average slope steepness on a clay loam soil at Girdarasha site in
September, 2007. The objective of this experiment was to test the performance of six treatments mentioned in the previous item on runoff
inducement during 2007 and 2008. Each treatment was replicated twice in a
randomized completely block design.
E) Runoff strip experiment. The objective was to determine the appropriate
catchment area to cultivated area ratio (C: CA ratio) for wheat
experimentally as influenced by the previous treatments at Girdarasha site
during 2006 / 2007. The C: CA ratios were (0.5: 1, 1: 1 and 2: 1), while the
soil treatments included (control, compaction, paraffin, spoiled oil, crude oil
and salt). Each treatment was replicated thrice in a randomized completely
block design. The response variables covered soil moisture profile, plant
height and wheat yield.
F) Applying a related model to determine the appropriate C: CA ratio for
some selected winter crops under various soil treatments. The input
requirements are: design annual rainfall depth, crop water requirement, and
runoff coefficient.

The recent irrigation techniques introduce automated irrigation using sophisticated equipments to supply water and nutrients to the plant as soon as they need it. Automated irrigation systems can increase crop yields, save water, energy and labor costs as compared with manual systems. Automatic irrigation systems presently available are costly and are not adopted by most of the small farmers. Therefore, appropriate low cost automatic irrigation technology has to be developed to facilitate high water use efficiency. In the present study low cost automated drip irrigation based on soil moisture has been developed. Soil moisture sensor was calibrated to switch off the motor when soil moisture reaches field capacity and switch on the motor when soil moisture reaches 80% of field capacity.

Проектирование системы Большого Ставропольского канала было начато в 1935 г. в соответствии с постановлением Совнаркома СССР и Цк ВкП(б) от 27 апреля 1935 г. «О полном обеспечении Ставрополья водой». Все довоенные проекты отличались исключительной сложностью исполнения и давали ограниченный экономический эффект. Реализация проекта была прервана Великой Отечественной войной. В 1957 г. гидростроители приступили к созданию Кубань-калаусской обводнительно-оросительной системы, названной Большим Ставропольским каналом (БСК). Задача БСК – завершить обводнение засушливого Центрального Предкавказья. Решение о создании самой грандиозной в Европейской части СССР обводнительно-оросительной системы было принято в 1941 г. Великая Отечественная война задержала осуществление этих планов на шестнадцать лет. Строительство БСК осуществлялось очередями и до сих пор не закончено.

Skip to main page content HOME CURRENT ISSUE ARCHIVE FEEDBACK SUBSCRIPTIONS ALERTS HELP Keywords Search Advanced »User Name Password Sign In Modeling phosphorus transport in agricultural watersheds: Processes and possibilities A. N. Sharpley, P. J. A. Kleinman, R. W. McDowell, M. Gitau, and R. B. Bryant ABSTRACT: Modeling phosphorus (P) loss from agricultural watersheds is key to quantifying the long term water quality benefits of alternative best management practices. Scientists engaged in this endeavor struggle to represent processes controlling P transport at scales and time frames that are meaningful to farmers, resource managers, and policy makers. To help overcome these challenges, we reviewed salient issues facing scientists that model P transport, providing a conceptual framework from which process-based P transport models might be evaluated. Recent advances in quantifying the release of soil P to overland and subsurface flow show that extraction coefficients relating soil a...

Mounding often occurs beneath engineering structures designed to infiltrate reuse water. AQTESOLV software and a spreadsheet solution for Hantush, together with soil moisture water balance (SWAGMAN farm model), were used for quantitatively predicting the height and extent of groundwater mounding underground to assess the groundwater-flow simulations of infiltration from a hypothetical irrigation site. Horizontal and vertical permeability, aquifer thickness, specific yield, and basin geometry are among the aquifer and recharge properties inputs. For 2.2 ha sites, the maximum heights of the simulated groundwater mound ranges up to 0.29 m. The maximum areal extent of groundwater mounding measured from the edge of the infiltration basins of 0.24 m ranges from 0 to 75 m. Additionally, the simulated height and extent of the groundwater mounding associated with a hypothetical irrigation infiltration basin for 2.2 ha development may be applicable to sites of different sizes, using the recharge rate estimated from the SWAGMAN farm model. For example, for a 2.2 ha site with a 0.0002 m/day recharge rate, the irrigation infiltration basin design capacity (and associated groundwater mound) would be the same as for a 1.1 ha site with a 0.0004 m/day recharge rate if the physical characteristics of the aquifer are unchanged. The study claimed that the present modelling approach overcomes the complications of solving the Hantush equation for transient flow. The approach utilised in this study can be applied for other purposes such as measuring the feasibility of infiltrating water, attenuation zone, risk mitigation essential for decision-makers and planning regulators in terms of environmental effects and water use efficiency.

Desalination industry in The United Arab Emirates, as in other Gulf countries, represents the principal source of potable water and water needs for industrial and civil use. It is then important to ensure purity and safety of desalted water before consumption by end users. Disinfection is performed to guarantee sterility and freedom of desalted water from pathogenic and microbial contaminants. Chlorination is one of the most effective and economic methods implemented for water disinfection where chlorine or chlorine-derivatives are normally used as a biocide. For many years, chlorine gas produced in-site in mercury cells continued to be in use by ADWEA’s desalination and power plants for the disinfection of desalted water and seawater intake. However, for environmental safety and fear of possible massive toxicity, it was decided to ban chlorine gas production and use sodium hypochlorite (NaOCl) instead. Hypochlorination plants were then built within ADWEA’s power stations for local production of hypochlorite solution through seawater electrolysis in non-mercury, no diaphragm cells. The resulting disinfectant is injected in product water as a crude chlorinating agent contained in the residual seawater matrix. Contamination problems arise from the ability of chlorine to react with naturally occurring bromide and organics in seawater to form disinfection byproducts (DBP) including bromate and halo-organics.
Bromate (BrO3-) is suspected as a carcinogen to human beings while being mutagenic and carcinogenic to rats and rodents. The urinary system in male rats was found to be more sensitive to attack with cancer due to chronic exposure to high concentrations of bromate in drinking water for lifetime. The WHO guidelines limit the maximum level of bromate ion in drinking water to 10  gL-1 (10 ppb).
In an initial step to study the bromate problem in potable water, samples of water from different locations in each one of ADWEA’s plants were collected and analyzed to find out bromate ion concentration. Bottled water samples were also analyzed for the same purpose. Results showed that the maximum allowable level of bromate in product water was exceeded by far allover ADWEA’s plants. Similarly, levels as high as 70 g L-1 were detected in bottled water samples collected from plants that use ADWEA’s water for further purification (particularly ozonation).
Possible solutions for the bromate problem are still under investigation on the lab scale. Short term solution relies on the production of sodium hypochlorite by the electrolysis of food grade salt (NaCl) solutions which are bromide-free.
Long term strategy requires research in a number of engineering and science areas where elimination of bromide ions from seawater upstream the electrolyzer or bromate removal after electrolysis is performed. Although replacement of the existing electro-chlorination systems in ADWEA’s plants is an alternative solution, economic design modifications to the existing plants would be preferable to combat bromate contamination of drinking water.
This paper outlines the basic features of hypochlorination process and hypochlorination plants in use by ADWEA. Research efforts done to date for developing efficient techniques for bromate removal from drinking water are summarized. Limitations of these techniques and possibility for implementation to eliminate bromate from ADWEA's hypochlorination systems are discussed.
Until a radical solution is developed to remediate bromate formation problem in drinking water, the short term and long term policies adopted by ADWEA to solve this problem and meet the WHO guideline are briefly outlined.

Finally, a proposal for process modification of the existing electrochlorination plants of ADWEA, to reduce bromate level to about 8 ppm in hypochlorite solution formed on the site is presented. The modified process, that needs research and verification, tries to keep using seawater as a costless and unlimited source of feed water to the electrolyzer.

The land of Tambong watershed conditions have experienced of degradation, in consequence of erosion. This research is aim to optimace of land use in management of Tambong watershed in Banyuwangi pursuant to Synthetic Unit Hydrograph of US SCS with use HEC-HMS. Pursuant to condition in site Tambong watershed have average value of CN equal to 91,33%, average value of % absorption equal to 12,54 %, average of % impervious equal to 70,95 %, average of slope equal to 2% and average of time lag equal to 6 clock. Assess
optimation of land in Tambong watershed can be shown from relation peak discharge (Qp) and assess CN with equation of regression y = 0,0119.X + 73,465 obtained by average value of optimum CN equal to 73,50% categorized assess CN B. The annual average of erosion rate in Tambong watershed equal to 0,66 mm/th with highest erosion rate equal to 14,43 mm/th in area of Licin hills at coppice land. Zona danger of erosion rate which have the critical potency lay in land use of plantation and forest. Need existence of action of conservation of land use in area of Licin hills and planning of building of conservation at plantation area.
Keywords : Land Use, HEC-HMS, US SCS

Mulugetta Mekuria is a senior scien-tist with the Socioeconomics Program, based at the International Maize and Wheat Improve-ment Centre (CIMMYT) Southern Africa Regional Office based in Harare, Zimbabwe. Christian Thierfelder is a conservation agriculture specialist with CIMMYT Southern Africa Regional Office based in Harare, Zimbabwe. Abstract: Understanding factors affecting farmers' adoption of improved technologies is crit-ical to success of conservation agriculture (CA) program implementation. This study, which explored the factors that determine adoption and extent of farmers' use of the three principles of CA (i.e., minimum soil disturbance, permanent soil cover with crop residues, and crop rotations), was conducted in 10 target communities in 8 extension planning areas in Malawi. The primary data was collected using structured questionnaires administered to individual households. Triangulation with key informant interviews, field observations, and interactive discus...