This document discusses water harvesting techniques for rainfed areas. It begins with an introduction and definitions of water harvesting. It then discusses the components of water harvesting systems, including catchment areas, storage facilities, and targets. It describes various types of water harvesting techniques, including microcatchments and macrocatchments. Success stories from Jordan, Egypt, and Tunisia are provided. The document concludes by discussing the economics and role of water harvesting in combating desertification.
For More Visit - www.civilengineeringadda.com
Irrigation Efficiency
Water conveyance Efficiency
It takes into account, conveyance or transit losses such as seepage through canal and evaporation through it.
η_c=W_f/W_r ×100
Where, Wf = water delivered to the field
Wr = water delivered from river or stream
Water Application Efficiency
It is the ratio of water stored in root zone to the water delivered to the field.
η_a=W_s/W_f ×100
Where, WS = water weight stored in root zone
WS = Wf – deep percolation – runoff
Wf = water delivered to the field
This efficiency is also called as farm efficiency and it depends on the irrigation technique that has been adopted.
Water use efficiency
It is the ratio of water used beneficially or consumptively to the water delivered to the field.
η_u=W_u/W_f ×100
Where, Wf = water delivered to the field
WU = consumptively used water
Water Storage Efficiency
This is the ratio of actual water stored in the root zone to the water needed to be stored to bring the moisture content upto field capacity.
Water Distribution efficiency
This evaluate the degree to which water is uniformly distributed to the root zone throughout the field area.
η_d=(1-y/d)×100
Where, d = average depth
y = Average numerical deviation in the depth of water stored from the average depth stored during irrigation
Question – the depths of penetration along the length of a border strip at points 30 m apart were proved. There observed values are 2 m, 1.9 m, 1.8 m, 1.6 m and 1.5 m. Compute the water distribution efficiency.
Solution –
Water distribution efficiency,
η_d=(1-y/d)×100
Where, d = average depth
d = (2+1.9+1.8+1.6+1.5)/5=1.76
And y = average numerical deviation
y = 1/5((2-1.76)+(1.9-1.76)+(1.8-1.76)+(1.76-1.6)+(1.76-1.5)=0.168
Therefore,
η_d=(1-0.168/1.76)×100
η_d=90.45%
Consumptive Use Efficiency
It is the ratio of water used consumptively to the net amount of water from the root zone.
Soil water conservation methods in agricultureVaishali Sharma
This presentation includes introduction as well as all the methods in agriculture either engineering or agronomic measures used in conservation of soil and water against erosion or other deteriorative factors.
Soil water movement
Soil water movement
Soil water movement
Soil water movementSoil water movementSoil water movementSoil water movementSoil water movementSoil water movementSoil water movementSoil water movementSoil water movementSoil water movementSoil water movementSoil water movementSoil water movementSoil water movementSoil water movementSoil water movementSoil water movementSoil water movementSoil water movementSoil water movementSoil water movementSoil water movementSoil water movementSoil water movement
For More Visit - www.civilengineeringadda.com
Irrigation Efficiency
Water conveyance Efficiency
It takes into account, conveyance or transit losses such as seepage through canal and evaporation through it.
η_c=W_f/W_r ×100
Where, Wf = water delivered to the field
Wr = water delivered from river or stream
Water Application Efficiency
It is the ratio of water stored in root zone to the water delivered to the field.
η_a=W_s/W_f ×100
Where, WS = water weight stored in root zone
WS = Wf – deep percolation – runoff
Wf = water delivered to the field
This efficiency is also called as farm efficiency and it depends on the irrigation technique that has been adopted.
Water use efficiency
It is the ratio of water used beneficially or consumptively to the water delivered to the field.
η_u=W_u/W_f ×100
Where, Wf = water delivered to the field
WU = consumptively used water
Water Storage Efficiency
This is the ratio of actual water stored in the root zone to the water needed to be stored to bring the moisture content upto field capacity.
Water Distribution efficiency
This evaluate the degree to which water is uniformly distributed to the root zone throughout the field area.
η_d=(1-y/d)×100
Where, d = average depth
y = Average numerical deviation in the depth of water stored from the average depth stored during irrigation
Question – the depths of penetration along the length of a border strip at points 30 m apart were proved. There observed values are 2 m, 1.9 m, 1.8 m, 1.6 m and 1.5 m. Compute the water distribution efficiency.
Solution –
Water distribution efficiency,
η_d=(1-y/d)×100
Where, d = average depth
d = (2+1.9+1.8+1.6+1.5)/5=1.76
And y = average numerical deviation
y = 1/5((2-1.76)+(1.9-1.76)+(1.8-1.76)+(1.76-1.6)+(1.76-1.5)=0.168
Therefore,
η_d=(1-0.168/1.76)×100
η_d=90.45%
Consumptive Use Efficiency
It is the ratio of water used consumptively to the net amount of water from the root zone.
Soil water conservation methods in agricultureVaishali Sharma
This presentation includes introduction as well as all the methods in agriculture either engineering or agronomic measures used in conservation of soil and water against erosion or other deteriorative factors.
Soil water movement
Soil water movement
Soil water movement
Soil water movementSoil water movementSoil water movementSoil water movementSoil water movementSoil water movementSoil water movementSoil water movementSoil water movementSoil water movementSoil water movementSoil water movementSoil water movementSoil water movementSoil water movementSoil water movementSoil water movementSoil water movementSoil water movementSoil water movementSoil water movementSoil water movementSoil water movementSoil water movement
Soil moisture conservation role of mulching and hydrophilic polymerssukhjinder mann
Soil moisture conservation role of mulching and hydrophilic polymers; Methods to conserve moisture, mulch types, polymer types, importance, advantages and disadvantages
In this topic, water which is as much as essential as soil was discussed and we’ll see how the soil, plant and water interact with each other and have a sustainable agricultural knowledge in producing staple food.
Soils can process and hold considerable amount of water. They can take in water, and will keep doing so until they are full, or until the rate at which they can transmit water into and through the pores is exceeded. Some of this water will steadily drain through the soil (via gravity) and end up in the waterways and streams, but much of it will be retained, despite the influence of gravity. Much of this retained water can be used by plants and other organisms, thus contributing to land productivity and soil health.
Soil moisture distribution pattern under surface subsurface drip irrigationArpna bajpai
Moisture distribution pattern is one of the basic requirements for efficient design and management of an irrigation system. The knowledge of moisture distribution pattern helps in the effectiveness of drip irrigation
Soil moisture conservation role of mulching and hydrophilic polymerssukhjinder mann
Soil moisture conservation role of mulching and hydrophilic polymers; Methods to conserve moisture, mulch types, polymer types, importance, advantages and disadvantages
In this topic, water which is as much as essential as soil was discussed and we’ll see how the soil, plant and water interact with each other and have a sustainable agricultural knowledge in producing staple food.
Soils can process and hold considerable amount of water. They can take in water, and will keep doing so until they are full, or until the rate at which they can transmit water into and through the pores is exceeded. Some of this water will steadily drain through the soil (via gravity) and end up in the waterways and streams, but much of it will be retained, despite the influence of gravity. Much of this retained water can be used by plants and other organisms, thus contributing to land productivity and soil health.
Soil moisture distribution pattern under surface subsurface drip irrigationArpna bajpai
Moisture distribution pattern is one of the basic requirements for efficient design and management of an irrigation system. The knowledge of moisture distribution pattern helps in the effectiveness of drip irrigation
Rainwater harvesting (RWH) considering as a technique system is being exploited of the variance topographic nature of the earth's surface, such as the use of valleys, depressions and oases , or through the berms or small dams from stone or cisterns building , to collect then reserve and store rainwater and floods during winter periods in various ways that differs in the purpose of collecting them depending on their rainfall rates and reuse when needed, whether for drinking, supplementary agricultural irrigation or to feed groundwater. Iraq in general and Nineveh Governorate in particular have been experiencing severe environmental conditions in the past two years, (2020/2021) & (2021/2022), and the most important of which is the rainfall lowing and the increasing demographic growth offset by significant water consumption, so as to ensure continued food production, increased irrigation projects have become urgent. Iraq is one of the countries that suffers from water scarcity in general and the amount of rainfall ranges (99.8 billion cubic meters/year) fluctuating and irregular distribution, so it requires investing this quantity and managing its use rationally by the system of rainwater harvesting .Northern of Iraq, including Nineveh Governorate is characterize by cereal winter crops production by depends mainly on rain fall to produce winter crops such as Wheat and Barley by rainfed agriculture method with rain requirements of more than (400mm/year), the rate of rainfall for a period (1970-2011) reached (170.3 mm/year).The rainy season in Nineveh Governorate extends from November to the end of May with fluctuating falls and small amounts that do not meet the needs of agricultural crops. This current study was prepared to activate the potential for harvesting rainwater for agricultural uses in the rain-fed areas prevailing in Nineveh Governorate. The agricultural system in semi-dry areas, including Nineveh Governorate, suffers from drought due to lack of rain and lack of yield in winter crops, including wheat and barley, which attracts the attention of researchers and stakeholders in finding a strategic solution to this problem, which lies in the activation of rainwater harvesting techniques, which is an integrated system for water management in rain lands in semi-dry areas to meet the lack of water need for agricultural crops. This system includes facilitating the flow of rainwater through canyons according to the decline of the land towards depressions, valleys and water basins prepared for this purpose to conduct supplementary irrigation with sprinkler irrigation techniques to activate the productivity of agricultural crops ,improve the performance capacity of rainfed farming systems, sustain green cover, reduce biodiversity extinction and address the problem of environmental drought to achieve agricultural sustainability.
Welcome to International Journal of Engineering Research and Development (IJERD)IJERD Editor
journal publishing, how to publish research paper, Call For research paper, international journal, publishing a paper, IJERD, journal of science and technology, how to get a research paper published, publishing a paper, publishing of journal, publishing of research paper, reserach and review articles, IJERD Journal, How to publish your research paper, publish research paper, open access engineering journal, Engineering journal, Mathemetics journal, Physics journal, Chemistry journal, Computer Engineering, Computer Science journal, how to submit your paper, peer reviw journal, indexed journal, reserach and review articles, engineering journal, www.ijerd.com, research journals,
yahoo journals, bing journals, International Journal of Engineering Research and Development, google journals, hard copy of journal
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
DAM Site Selection Using GIS Techniques and remote sensing to Minimize Flash ...inventionjournals
In the last few years devastating flash floods descending downstream through valleys had occurred in East Nile Locality-Sudan. A flash flood can be caused by intense rain, particularly when it takes place in a saturated area where rain has previously fallen. Under these conditions the additional rain runs off over the surface and accumulates in streams and channels at a much accelerated pace. The flooded water had caused a considerable damage in houses, roads and properties. Construction of earth dams is suggested to minimize the destructive effect of these flash floods and make use of stored water in agriculture and grazing. To determine the location of earth dams, multi criterion methods had been used. The best dam location had been achieved applying the selection criterion. The surface areas, volume of reservoirs, had been determined for every selected location Using ArcGIS. Major Landuse, landcover, stream order and location of water body had projected on the watershed area of the Soba valley to extract the residential areas, agricultural areas and grassland effected by suggested dams. Dam location selection model and volume model had been designed to repeat the steps and report the analysis results automatically.
Comparing Evolved Extractive Text Summary Scores of Bidirectional Encoder Rep...University of Maribor
Slides from:
11th International Conference on Electrical, Electronics and Computer Engineering (IcETRAN), Niš, 3-6 June 2024
Track: Artificial Intelligence
https://www.etran.rs/2024/en/home-english/
Cancer cell metabolism: special Reference to Lactate PathwayAADYARAJPANDEY1
Normal Cell Metabolism:
Cellular respiration describes the series of steps that cells use to break down sugar and other chemicals to get the energy we need to function.
Energy is stored in the bonds of glucose and when glucose is broken down, much of that energy is released.
Cell utilize energy in the form of ATP.
The first step of respiration is called glycolysis. In a series of steps, glycolysis breaks glucose into two smaller molecules - a chemical called pyruvate. A small amount of ATP is formed during this process.
Most healthy cells continue the breakdown in a second process, called the Kreb's cycle. The Kreb's cycle allows cells to “burn” the pyruvates made in glycolysis to get more ATP.
The last step in the breakdown of glucose is called oxidative phosphorylation (Ox-Phos).
It takes place in specialized cell structures called mitochondria. This process produces a large amount of ATP. Importantly, cells need oxygen to complete oxidative phosphorylation.
If a cell completes only glycolysis, only 2 molecules of ATP are made per glucose. However, if the cell completes the entire respiration process (glycolysis - Kreb's - oxidative phosphorylation), about 36 molecules of ATP are created, giving it much more energy to use.
IN CANCER CELL:
Unlike healthy cells that "burn" the entire molecule of sugar to capture a large amount of energy as ATP, cancer cells are wasteful.
Cancer cells only partially break down sugar molecules. They overuse the first step of respiration, glycolysis. They frequently do not complete the second step, oxidative phosphorylation.
This results in only 2 molecules of ATP per each glucose molecule instead of the 36 or so ATPs healthy cells gain. As a result, cancer cells need to use a lot more sugar molecules to get enough energy to survive.
Unlike healthy cells that "burn" the entire molecule of sugar to capture a large amount of energy as ATP, cancer cells are wasteful.
Cancer cells only partially break down sugar molecules. They overuse the first step of respiration, glycolysis. They frequently do not complete the second step, oxidative phosphorylation.
This results in only 2 molecules of ATP per each glucose molecule instead of the 36 or so ATPs healthy cells gain. As a result, cancer cells need to use a lot more sugar molecules to get enough energy to survive.
introduction to WARBERG PHENOMENA:
WARBURG EFFECT Usually, cancer cells are highly glycolytic (glucose addiction) and take up more glucose than do normal cells from outside.
Otto Heinrich Warburg (; 8 October 1883 – 1 August 1970) In 1931 was awarded the Nobel Prize in Physiology for his "discovery of the nature and mode of action of the respiratory enzyme.
WARNBURG EFFECT : cancer cells under aerobic (well-oxygenated) conditions to metabolize glucose to lactate (aerobic glycolysis) is known as the Warburg effect. Warburg made the observation that tumor slices consume glucose and secrete lactate at a higher rate than normal tissues.
Richard's entangled aventures in wonderlandRichard Gill
Since the loophole-free Bell experiments of 2020 and the Nobel prizes in physics of 2022, critics of Bell's work have retreated to the fortress of super-determinism. Now, super-determinism is a derogatory word - it just means "determinism". Palmer, Hance and Hossenfelder argue that quantum mechanics and determinism are not incompatible, using a sophisticated mathematical construction based on a subtle thinning of allowed states and measurements in quantum mechanics, such that what is left appears to make Bell's argument fail, without altering the empirical predictions of quantum mechanics. I think however that it is a smoke screen, and the slogan "lost in math" comes to my mind. I will discuss some other recent disproofs of Bell's theorem using the language of causality based on causal graphs. Causal thinking is also central to law and justice. I will mention surprising connections to my work on serial killer nurse cases, in particular the Dutch case of Lucia de Berk and the current UK case of Lucy Letby.
What is greenhouse gasses and how many gasses are there to affect the Earth.moosaasad1975
What are greenhouse gasses how they affect the earth and its environment what is the future of the environment and earth how the weather and the climate effects.
Observation of Io’s Resurfacing via Plume Deposition Using Ground-based Adapt...Sérgio Sacani
Since volcanic activity was first discovered on Io from Voyager images in 1979, changes
on Io’s surface have been monitored from both spacecraft and ground-based telescopes.
Here, we present the highest spatial resolution images of Io ever obtained from a groundbased telescope. These images, acquired by the SHARK-VIS instrument on the Large
Binocular Telescope, show evidence of a major resurfacing event on Io’s trailing hemisphere. When compared to the most recent spacecraft images, the SHARK-VIS images
show that a plume deposit from a powerful eruption at Pillan Patera has covered part
of the long-lived Pele plume deposit. Although this type of resurfacing event may be common on Io, few have been detected due to the rarity of spacecraft visits and the previously low spatial resolution available from Earth-based telescopes. The SHARK-VIS instrument ushers in a new era of high resolution imaging of Io’s surface using adaptive
optics at visible wavelengths.
(May 29th, 2024) Advancements in Intravital Microscopy- Insights for Preclini...Scintica Instrumentation
Intravital microscopy (IVM) is a powerful tool utilized to study cellular behavior over time and space in vivo. Much of our understanding of cell biology has been accomplished using various in vitro and ex vivo methods; however, these studies do not necessarily reflect the natural dynamics of biological processes. Unlike traditional cell culture or fixed tissue imaging, IVM allows for the ultra-fast high-resolution imaging of cellular processes over time and space and were studied in its natural environment. Real-time visualization of biological processes in the context of an intact organism helps maintain physiological relevance and provide insights into the progression of disease, response to treatments or developmental processes.
In this webinar we give an overview of advanced applications of the IVM system in preclinical research. IVIM technology is a provider of all-in-one intravital microscopy systems and solutions optimized for in vivo imaging of live animal models at sub-micron resolution. The system’s unique features and user-friendly software enables researchers to probe fast dynamic biological processes such as immune cell tracking, cell-cell interaction as well as vascularization and tumor metastasis with exceptional detail. This webinar will also give an overview of IVM being utilized in drug development, offering a view into the intricate interaction between drugs/nanoparticles and tissues in vivo and allows for the evaluation of therapeutic intervention in a variety of tissues and organs. This interdisciplinary collaboration continues to drive the advancements of novel therapeutic strategies.
Multi-source connectivity as the driver of solar wind variability in the heli...Sérgio Sacani
The ambient solar wind that flls the heliosphere originates from multiple
sources in the solar corona and is highly structured. It is often described
as high-speed, relatively homogeneous, plasma streams from coronal
holes and slow-speed, highly variable, streams whose source regions are
under debate. A key goal of ESA/NASA’s Solar Orbiter mission is to identify
solar wind sources and understand what drives the complexity seen in the
heliosphere. By combining magnetic feld modelling and spectroscopic
techniques with high-resolution observations and measurements, we show
that the solar wind variability detected in situ by Solar Orbiter in March
2022 is driven by spatio-temporal changes in the magnetic connectivity to
multiple sources in the solar atmosphere. The magnetic feld footpoints
connected to the spacecraft moved from the boundaries of a coronal hole
to one active region (12961) and then across to another region (12957). This
is refected in the in situ measurements, which show the transition from fast
to highly Alfvénic then to slow solar wind that is disrupted by the arrival of
a coronal mass ejection. Our results describe solar wind variability at 0.5 au
but are applicable to near-Earth observatories.
1. INSTITUTE OF AGRICULTURAL SCIENCES
RGSC BHU
Rural Agricultural Work Experience
SSC-411, 4(0+4)
Topic on: - Water Harvesting Techniques For Rainfed Areas
Submitted to:- Submitted by:-
Dr. Ashish Latare Ram Singh
Dr. Sumit Rai Id no. - 15337
(Asst. Prof. IAS, RGSC, BHU) B.Sc. (Ag) 4thYear.
4/9/2018 1
2. overview
4/9/2018 2
1. Introduction, concept & definition of WH
2. WH in past & present
3. Components of WH systems
4. Types of WH
5. Some success stories &
6. Combating desertification
3. Where does rainwater in the dry environments go?
• A large part of the rainfall returns to the atmosphere directly by evaporation from
the soil surface and also a part of that infiltrated into the soil .
• The part that flows as run-off, if not intercepted, goes to slumps, losing its good quality
and evaporating, it may even flow into the sea.
4/9/2018 3
6. 4/9/2018 6
Concept & Definition
1.) The principle of agricultural rainwater harvesting is based on the
concept of depriving part of the land of its share of precipitation,
2.) Which is usually small and non-productive, and giving it to another part to
increase the amount of water available to the latter part, which originally was
not sufficient,
3.) And to bring this amount closer to the crop water requirements so that
an economical agricultural production can be achieved.
7. 4/9/2018 7
● The process of concentrating precipitation through run-off and storing it
for beneficial use.
• Critchley and Siegert (1991) simply define WH as ‘collection of run-off for
its productive use’
• WH is a hydroagronomic term covering a whole range of methods of collecting
and concentrating various forms of run-off.
8. 4/9/2018 8
Water harvesting in the past and the present
Ancient and indigenous WH systems exist in many parts of the world and from
many areas,
Such as contour terracing in the central highlands of Mexico (UNEP, 1983)
Food water farming in desert areas of Arizona and northern Mexico,
Khadin systems in Rajasthan, India, initiated probably in the 15th century
(Kolarkar et al., 1983).
9. 4/9/2018 9
Components and applicability of the system
All WH systems must have the following components:
1. Catchment area/run-off area
varying from a few square metres (microcatchment) to as large as several square kilometres
(macrocatchment): the part of the land where a portion or all of the precipitation which falls on it
runs off its boundaries. It can be agricultural, rocky or marginal land, or even a rooftop or a paved
road.
10. 4/9/2018 10
2. Storage facility:
The place where the run-off water is held from the time it occurs until it is utilized by
crops, animals, human beings .
Storage can be:
(i) Above the soil surface as in surface reservoirs or ponds;
(ii) In the soil profile as soil moisture.
(iii) Underground in cisterns or as groundwater in aquifers.
3. Target or use:
The beneficiary of the stored water. In agricultural production, the target is the plant or the
animal, whereas in domestic use, it refers to human beings and their needs
12. 4/9/2018 12
Methods and Relevant Conditions
Classification of water-harvesting systems
The geometric configuration of WH systems depends upon the topography
Water-harvesting techniques may be grouped into two categories.
1.) First, techniques that directly supply run-off water from a small catchment to the crop, and
thus water accumulates around the plant, infiltrates into the soil and is stored in the crop root
zone. These are called microcatchment techniques, because the run-off-yielding catchments are
usually small and directly adjacent to the targeted crop.
13. 4/9/2018 13
2.) The other category is macrocatchment techniques
• which concentrate rainwater run-off flowing in an ephemeral wadi (natural channel)
and store it in a prepared storage facility (such as a reservoir) for subsequent beneficial use.
• This category also includes macrocatchment techniques in which water is diverted
(by proper damming or cross-structure) out of the wadi course to inundate nearby lands.
• The widely used microcatchment WH techniques are contour ridges, semicircular
and trapezoidal bunds, and small run-off basins.
• Macrocatchment systems are characterized by having run-off water collected from
relatively large catchments.
15. 4/9/2018 15
A success story for microcatchment WH
Small run-off-harvesting basins for fruit trees in Jordan.
The arid land of Jordan is of Mediterranean climate, with a mean annual
rainfall of 100–200 mm, which occurs mainly in the cold winter, from
December to March.
Farmers in the area depend on livestock using poor natural vegetation
and limited groundwater for domestic use.
There are no fruit trees without irrigation in this zone.
In 1987, a project was launched by the University of Jordan to diversify
farmers’ production by introducing tree crops using additional water from
microcatchment water-harvesting system.
The negarim (small diamond basins) system with plots of 50–100 m² was
constructed on deep soils
18. 4/9/2018 18
Cisterns in north-western Egypt.
Cisterns are ancient, indigenous rainwater-harvesting systems, used mainly for
supplying human and animal water needs in water-scarce areas.
They are usually subsurface reservoirs, with capacity ranging from 10 to 500 m³.
Modern concrete cisterns are now being constructed in places where there is no
such rocky layer.
Water is used not only for human and animal needs but also for growing cash
crops in home gardens.
21. 4/9/2018 21
Economics of Water Harvesting
Direct versus indirect benefits
Most of the available work on WH deals with technical, agronomical and social
aspects of this practice; however, few and inconclusive assessments are available
on the economical feasibility of WH in the drier environments.
Benefits of WH,
Benefits of WH in these environments include, in addition to food and feed
production (direct benefits), substantial environmental and social returns,
such as combating land degradation and migration from rural to urban areas
and employment.
22. 4/9/2018 22
Methodologies for evaluating indirect benefits are sometimes controversial and
the private sector is often not interested in these benefits.
Economic assessment of macrocatchments WH is more complicated because
of the upstream–downstream interactions in addition to social and environmental issues.
23. 4/9/2018 23
Microcatchments for field crops
• In arid and semi-arid regions, limited water availability and soil fertility,
in almost all cases, are the major constraints to dry farming.
• It is generally recognized that WH can significantly increase crop yields in such areas
Macrocatchments in sub-Saharan Africa
• A second case study for economic assessment of WH is from Africa. Rainwater harvesting
(RWH) is being widely promoted as a way to improve the production of crops and livestock
in semi-arid areas of eastern and Southern Africa.
24. 4/9/2018 24
Water Harvesting for Supplemental Irrigation
In Kenya (Machakos district) and Burkina Faso (Ouagouya), there is significant
scope for improving water productivity in rainfed farming through supplemental
irrigation, especially if combined with soil fertility management.
Surface run-off from small catchments (1–2 ha) was harvested and stored in
manually dug farm ponds (100–250 m³storage capacity). Simple gravityfed
furrow irrigation was used.
25. 4/9/2018 25
Combating Desertification with Water Harvesting
Problems in deserts
• Rangelands in the dry areas are a very fragile ecosystem.
• They receive inadequate annual rainfall for economical dry farming.
• Natural vegetation and plants undergo severe moisturestress periods,
which significantly reduce growth and result in very poor vegetative cover.
• Part of the rain which flows as run-off usually forms erosive streams and
results in severe soil erosion and land degradation.
26. 4/9/2018 26
Role of WH in combating desertification
• Increasing consumer demand for sheep, meat and milk, in combination with
rapid population growth and inappropriate government policies, have stimulated
a substantial increase in the livestock population.
• Water harvesting can improve the vegetative cover,
• increase the carrying grazing capacity of rangeland and
• help halt environmental degradation
27. 27
(a) field plot and shrub after 2 years showing water harvested after a storm;
Manually developed semicircular bunds:
30. 4/9/2018 30
Conclusions
Water harvesting is one option that increases the amount of water per unit cropping area,
reduces drought impact and enables the use of run-off beneficially.
It is low-external-input technology that makes farming possible on part of the land,
provided other production factors such as climate, soils and crops are favourable.
Water harvesting has been found to be effective in recharging groundwater aquifers.
Rainwater harvesting should suit its purpose, be accepted by the local population and
be sustainable in the local environment.
31. 4/9/2018 31
The implementation of WH, however, requires taking care
of possible drawbacks such as:
(i) increased soil erosion and loss of habitat of flora and fauna in macrocatchments
(ii) upstream–downstream conflicts
(iii) competition among farmers and herders.