A levada is an irrigation channel or aqueduct specific to the Portugese island of Madeira. They were created from the sixteenth century to carry water across the island from the mountainous west and northwest of the island to the drier southeast, which is more conducive to habitation and agriculture
The total levadas network extends over 2150 km in this island 57 km long, 23km wide in the widest point.
We’ve been inspired by Fan Sheng-chih Shu. His writings from the first century BC describe a method of irrigation where a unglazed clay pot is buried in the soil. When filled with water, the clay pot turns into an amazing high-tech device. The micro-pores of the clay pot allows water to seep into the surrounding soil. A key characteristic is that the water seepage is regulated by the water needs of any nearby plant. When the plant’s water demands have been fulfilled and the soil is moist, the water seepage from the clay pot will stop. When the soil becomes dry, water seepage will begin again. This seepage is controlled by soil moisture tension. It’s automatic irrigation without timers or electronic sensors!
The link above give instructions to build an Olla Irrigator out of two clay pots. They also provide some notes on how to automatically fill the Ollas using a gravity feed.
The rest of their site is also quite interesting. They have a number of ideas for making self-watering planters out of buckets and other readily available materials, including methods to automate filling of the self-watering planter reservoirs.
I have seen the buried clay pot idea mentioned in a Bill Mollison video of permaculture in dry lands on Youtube (it could be this one).
"I think there needs to be a solution as soon as possible… Because these companies, they’re preying on the aquifer. And when the aquifer dries up, our future will be uncertain!"
-Dominga Rosario, who owns a patch of land in a neighborhood on the outskirts of Ica.
From The World, January 2012: Peru has become the world’s number one exporter of asparagus to places including Europe and the US. The boom there has pumped a lot of money into the economy, but it’s also pumped out a lot of water.
Formerly one of the four largest lakes in the world, the Aral Sea has been steadily shrinking since the 1960s after the rivers that fed it were diverted by Soviet irrigation projects. Although irrigation made the desert bloom, it devastated the Aral Sea.
For most crops, irrigation simply provides water for the plant’s roots. But in a Balinese rice terrace, water is used to construct a complex, pulsed artificial ecosystem. Water temples manipulate the states of the system, at ascending levels in regional hierarchies. The permanence of water temple networks contrasts sharply with the instability of the traditional Balinese states. Since the water temples are real, perhaps it is the Balinese “state” that is chimerical.
J. Stephen Lansing, “Balinese ‘Water Temples’ and the Management of Irrigation” American Anthropologist, vol 89, issue 2.
In his 1878 Report on the Lands of the Arid Region of the United States, John Wesley Powell, the first white explorer of the Colorado River, proposed to organise governance units of the West according to hydrological boundaries - watersheds - instead of state lines.
If Congress had followed his recommendations the Western United States would have been organised following this map.
Spain has a deep & rich Islamic history… And people wonder why Hispanics has the largest number of converts in the USA now.. It was once African Americans, which we understand why as well. Do your research and study history..
The Honghe Hani Rice Terraces, China, in Southern Yunnan, cascade down the slopes of the towering Ailao Mountains to the banks of the Hong River. Over the past 1300 years, the Hani people have developed a complex system of channels to bring water from the forested mountaintops to the terraces. They have also created an integrated farming system that involves buffalos, cattle, ducks, fish and eel and supports the production of red rice.