Groundwater irrigation efficiency and soil fertility in drylands

 

 

The water under your feet in Laos

The water beneath our feet is a valuable irrigation resource for farmers affected by drought in rural Laos, and can increase crop yields and income for farmers. Students at the Faculty of Water Resources and Management have created an experimental site to research groundwater irrigation efficiency and improve soil fertility. They found that the best way to save water is by using drip irrigation, and that the more crops were produced when compost was added to the soil.

 

Groundwater recharge occurs disproportionately from heavy rainfalls

Photo credit: Nature World News

Tropical groundwater resources may be more resilient to climate change than previously thought. Pictured here is an artesian well in central semi-arid Tanzania. (Photo : Jasechko, S & Taylor, R.G)

Tropical Groundwater Resources Benefit From Fewer, But More Intense Rainfall

By Samantha Mathewson

Tropical groundwater resources may be able to stand up to the challenges imposed by climate change, researchers from the University College London (UCL) and the University of Calgary report in a new study. Generally speaking, global warming leads to fewer but more intense rainfalls. However, this precipitation pattern seems to adequately recharge vital sources of freshwater.

Groundwater is an invaluable source of freshwater across the tropics, providing safe drinking water and a source of agricultural irrigation. It follows then, the replenishment of these sources is vital for sustaining the livelihoods and ecosystems that depend on the availability of freshwater.

For their study, researchers assessed the chemical signatures in precipitation and groundwater at 15 sites spread out across the tropics. This allowed them to compare the stable isotopes of hydrogen and oxygen found in these water molecules, from which they can interpret how heavy rainfalls impact groundwater recharge in surrounding areas. In terms of their study, heavy rainfall was defined as those exceeding the 50th percentile of local rainfall intensity. Therefore, their results suggest that groundwater recharge occurs disproportionately from heavy rainfalls, but the processes that carry intensive rainfall to groundwater systems and enhance the resilience of tropical groundwater storage as global temperatures rise remains unknown.

Read the full story: Nature World News

New project will reduce floods and boost irrigation

Photo credit: Google

Women worshiping in holy Ganga river during Sattuani festival in Patna on Tuesday.

 

Ganga floodwater to be stored underground

(30 Oct, 2015 – Uttar Pradesh, India) A new initiative launched today in Uttar Pradesh could revolutionize flood management while at the same time boost groundwater stocks for dry season irrigation. Located in Jiwai Jadid village, 20 kilometers east of Rampur town, the project will be the first ever to adopt the new approach which is being developed by scientists at the International Water Management Institute (IWMI).

The initiative, called Underground Taming of Floods for irrigation (UTFI), channels surplus surface water from flood‐prone rivers or their distributary canals during the wet season when there is a high flood risk to a modified village pond. Brick structures in the pond allow the water to flow swiftly down below ground, where they infiltrate the local aquifer. This water can then be pumped back up again during the dry season so that farmers can maintain or intensify their crop production.

“This is an exciting concept which has never really been done before and whose benefits go directly to local and wider communities,” said Paul Pavelic, of the International Water Management Institute (IWMI), who leads the research. “Putting this into practice will save on the large funds spent each year on relief and restoration efforts of flood victims and on subsidies for groundwater extraction during the non‐rainy season. We hope our approach would tackle the root causes of the problem rather than the consequences. ”

The Ganga basin suffers from regular floods with the mighty Ganga and its tributaries like Ramganga, Yamuna, Mahananda, Koshi all flooding almost annually. During the rainy season, large volumes of   excess water run off the Himalayan range often causing great damage downstream. On the other hand, some of the same regions face a shortage of water aggravated by year ‐ round agriculture production which is largely dependent on groundwater pumping particularly in dry season when canal water is limited. To deal with this variability, IWMI’s experts have devised a way to selectively capture excess water flows during monsoons and store this in aquifers underground.

The size of the land around the pilot that would receive direct benefit is currently under investigation. With floods being a common occurrence across the Ganga basin, researchers hope that the scaling up of this intervention would help in effectively protecting lives and assets downstream, boosting agricultural productivity and improving resilience to climate shocks at the river basin scale. This will be especially important to help communities deal with climate change which is likely to bring ever more variability in water supply and rainfall.

Read the full Press Release: IWMI

The impact of climate change on groundwater supply

Photo credit: Nature World News

Snowfall in the Sierra Nevada has decreased due to climate change. Because snow is an important source of groundwater recharge, scientists are monitoring it and releasing information on their findings. (Photo : Wikimedia Commons )

California and Drought: Sierra Nevada Groundwater Sources at Risk

By Samantha Mathewson

In and out of California’s drought, the Sierra Nevada’s snowpack plays a crucial role in groundwater recharge.

“The lower than historically normal snowfall in recent years is one environmental factor that has contributed to the current drought in California,” Ryan Webb, Ph.D. student in the department of civil and environmental engineering at Colorado State University, said in a statement.

With that in mind, Webb and other researchers set out to better understand the impact that climate change has on groundwater supply. They observed changes in soil wetting and drying that occur as snow melts in snowy, mountainous regions. They did this by examining subsurface water content levels in the Sierra Nevada Mountains, in soil that remains wet and unfrozen beneath winter snowpacks in this region, the statement said.

Read the full text: Nature World News

Underground ocean

Photo credit: IBT

Workers digging a well for underground water are dwarfed by the sand dunes of the Taklimakan Desert, 13 September 2003, outside of Tazhong, in China’s northwest Xinjiang province.(FREDERIC J. BROWN/AFP/Getty Images)

Vast hidden ‘ocean’ found under Chinese desert

By

Chinese scientists have discovered what could be a huge hidden ocean underneath one of the driest places on earth, the South China Morning Post reported on 30 July.

The Tarim basin in northwestern Xinjiang, China, is one of the driest places on Earth, but the vast amount of salt water concealed underneath could equal 10 times the water found in all five of theGreat Lakes in the US.

“This is a terrifying amount of water,” said professor Li Yan, who led the study at the Chinese Academy of Sciences’ Xinjiang Institute of Ecology and Geography in Urumqi, the Xinjiang capital.

“Never before have people dared to imagine so much water under the sand. Our definition of desert may have to change,” he told the South China Morning Post.

Scientists had long suspected that a vast amount of melt water from nearby mountains had slipped beneath the basin, but the exact amount of water remained unknown.

Accidental discovery

Li’s team made the discovery by accident. They had actually been looking for carbon dioxide, which is absorbed in certain areas – such as forests and oceans – called “carbon sinks.”

Scientists study carbon sinks to gain a greater understanding of climate change.

Around 10 years ago, the team discovered that carbon dioxide had been disappearing into the basin for 10 years, but could not understand why.

Read the full article: IBTimes

Groundwater is disappearing

Photo credit: Nature World News

Lake Mead, the largest reservoir in the United States. (Photo : Pixabay)

Earth’s Biggest Groundwater Basins Are in Trouble

A third of the Earth’s biggest groundwater basins are in trouble, because after significantly relying on this hidden resource for so long, they are being quickly tapped out, according to two new studies.

Groundwater comes from aquifers – sponge-like gravel and sand-filled underground reservoirs – that provide populations with freshwater to make up for surface water lost from drought-depleted lakes, rivers and reservoirs. With the ongoing drought in the western United States, particularly California, residents have been relying more heavily on groundwater for their water needs. And yet despite the fact that groundwater is disappearing, there is little to no accurate data about how much water remains in them – so we don’t know when we’ll run out.

“Available physical and chemical measurements are simply insufficient,” lead author Jay Famiglietti, from the University of California, Irvine (UCI), said in a news release. “Given how quickly we are consuming the world’s groundwater reserves, we need a coordinated global effort to determine how much is left.”

So for the first time, two new studies, led by researchers at UCI using data from NASA Gravity Recovery and Climate Experiment satellites, aimed to find out. NASA’s twin GRACE satellites measure dips and bumps in Earth’s gravity, which is affected by the weight of water.

Read the full story: Nature World News

Drought or No Drought ?

 

Apocalyptic Schadenfreude

What the New York Times — and everybody else — gets wrong about California’s water crisis.

By Steven Johnson

EXCERPT

But then I started spending more time in California and realized that the water situation there is far more complex than it had seemed from the Atlantic states. Which is why it has been particularly interesting to read the extensive coverage of California’s water crisis in the New York Times for the past few days, in the wake of Governor Brown’s executive order last week limiting water usage across the state. There has been some great reporting and data analysis in this sequence of stories. (This, for instance, is one of the most useful infographics I’ve seen all year.) Yet I think some of the complexity of the situation has been sacrificed in order to adhere to the familiar moral that the state’s residents are finally getting their environmental just deserts. Consider the opening paragraph of Sunday’s story:

———

But isn’t water a deal breaker? If you live in a region that doesn’t have water, you’re going to hit a wall eventually, and that lifestyle is going to come back to haunt you. Yet California is so big and so ecologically diverse that it’s impossible to condense it into a simple story of living-beyond-our-limits. Arizona is a desert; Nevada is a desert. But large parts of California are temperate rain forests; the mediterranean climate of Sonoma gets almost as much rain in an average year as New York. In the middle of an historic drought, the reservoirs in the Bay Area are close to capacity. Measured by the mile, and not state boundaries, lumping northern California in with the abuses of Palm Springs is like blaming Maine in August for the surge in air conditioning in steamy Washington, D.C.

——–

The single most important statistic in understanding the current crisis is this: 80% of California’s surface water supports the farms of the Central Valley. Compared to that massive flow, the residential abuses are almost an afterthought. If every single human being living south of Los Angeles packed up and moved to rainy Oregon, it wouldn’t improve California’s water situation as much as a mere 10% decrease in the water used by the Central Valley farmers.

Read the full story: Medium

A major water crisis in South Asia

Photo credit: Google

India’s thirst for groundwater is threatening a major water crisis, and adding to global sea level rise, says a report.

(http://www.impactlab.net/2009/10/04/indias-thirst-for-groundwater-raising-global-sea-levels/)

South Asia running out of groundwater

[NEW DELHI] India, Nepal, Bangladesh and Pakistan along with China account for nearly half of the world’s total groundwater use and these regions are expected to  experience serious deficits, says the UN World Water Development Report (WWDR 2015), Water for a Sustainable World 2015 released ahead of  World Water Day on 22 March.

WWDR 2015 explains the complex relationship between access to water and economic development using India as an example.  Between 1960 and 2000 India’s mechanised tube wells increased from one million to 19 million.

India has 26 million groundwater structures; Bangladesh and Pakistan each have around 5 million.

Read the full article: SciDevNet

Desertification due to misuse of the water

 

U.S. Desertification Caused by Government

[Government, not the Government]

You can see from the work of Bill Mollison and others that it’s quite possible to green the desert without massive infrastructure projects. The present desertification of the South-West of the United States is not a result of “climate change”, it’s the result of misuse of the water that’s always been there, under the ground, regardless of the periodic minor variations in climate.

VIDEOS

(1) California’s Water Crisis | True News

https://youtu.be/U4yqKxYlJrM

An in-depth look at the real cause of the California water crisis and the history which lead to this challenging situation. Why are farmers trying to grow water intensive crops in a desert environment? How could farming in a desert possibly be cost effective? What role do taxpayer funded dam projects and government subsidies play in this shortage? Stefan Molyneux, host of Freedomain Radio, breaks down at the hidden story behind this growing problem.

(2) Dryland Permaculture – Bill Mollison

Bill Mollison showing how permaculture can heal deserts in various parts of the world

https://youtu.be/JmdCIqNG5BI

A massive aquifer in North Kenya

Photo credit: Google

People cross from Somalia into Kenya at the Mandera border control

Kenya: Mandera Locals Drill Borehole, Find Aquifer

A massive aquifer has been discovered in Takaba subcounty of Mandera. An aquifer is an underground water reservoir.

Farming in Mandera - http://i.ytimg.com/vi/Y8csdOkCWVg/maxresdefault.jpg
Farming in Mandera – http://i.ytimg.com/vi/Y8csdOkCWVg/maxresdefault.jpg

See also the VIDEO: https://youtu.be/Y8csdOkCWVg

The discovery was made when the Mandera county government drilled a borehole at Darwed. The borehole on the aquifer sits upon a massive aquifer and pumps clean water at a rate of 30,0000 cubic metres per hour. Previously, residents relied on the borehole at Wangeidhan,15km from Takaba town. The Wangeidhan borehole, which produces salty water, served nearly 50,000 residents.

One of the large earth dams in Takaba - http://4.bp.blogspot.com/_toe57KgSI-c/Se1aY2hFGxI/AAAAAAAAAUw/2SsaZllLt-I/s320/IMG_5531.JPG
One of the large earth dams in Takaba – http://4.bp.blogspot.com/_toe57KgSI-c/Se1aY2hFGxI/AAAAAAAAAUw/2SsaZllLt-I/s320/IMG_5531.JPG

Governor Ali Roba joined the residents in celebrating the new project. He said his government will pump clean water to the surrounding towns. “Water has always been scarce in Takaba. It is unbelievable that sweet water was within the reach of Takaba people,” Roba said. He said his government will ensure residents and livestock have sufficient water during the dry season.

Camels being watered at a new borehole - http://4.bp.blogspot.com/_toe57KgSI-c/SeyXRLDZnFI/AAAAAAAAAUo/6y4ygGqD5RI/s320/IMG_5520.JPG
Camels being watered at a new borehole – http://4.bp.blogspot.com/_toe57KgSI-c/SeyXRLDZnFI/AAAAAAAAAUo/6y4ygGqD5RI/s320/IMG_5520.JPG

Read the full article : allAfrica

Groundwater management is key in Sri Lanka

Photo credit: IWMI

Small-scale carrot farming in Jaffna (photo: cc: Johanan Ottensooser on Flickr).

Good groundwater management is key to Jaffna’s social and economic revival

Sri Lanka News

Jaffna’s wells may not provide a year-round supply of clean water, but a mix of short and long-term options could provide communities with all the clean water they need,

says Dharshani Weerasekera

President in Jaffna: Farmers in Jaffna to fetch reasonable prices to their agricultural produces - http://www.asiantribune.com/sites/asiantribune.com/files/images/2012/Chunnakam_People_1.jpg
President in Jaffna: Farmers in Jaffna to fetch reasonable prices to their agricultural produces – http://www.asiantribune.com/sites/asiantribune.com/files/images/2012/Chunnakam_People_1.jpg

Has water replaced peace as the key to Jaffna’s progress? In the Jaffna Peninsula, in the northernmost part of Sri Lanka, the only source of fresh water for most of the year is that drawn from underground reservoirs. However, human activities are threatening these fragile and precious aquifers with contamination. Damage to this limited and irreplaceable resource would be extremely difficult or impossible to reverse. How can we ensure this does not happen?

http://g9jzk5cmc71uxhvd44wsj7zyx.wpengine.netdna-cdn.com/wp-content/uploads/2015/02/LL-pumping-groundwater-for-irrigation-in-Jaffna.jpg
http://g9jzk5cmc71uxhvd44wsj7zyx.wpengine.netdna-cdn.com/wp-content/uploads/2015/02/LL-pumping-groundwater-for-irrigation-in-Jaffna.jpg

The answer lies in how stakeholders address two major concerns. The first is groundwater contamination from the dumping of oil, sewage, agrochemicals and garbage into the ground. The second is the seawater intrusion of Jaffna’s limestone aquifers due to over-extraction of groundwater for domestic, agricultural and industrial purposes.

The rain falls mainly in the plain

 

Read the full article : IWMI

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