Bubble desalination latest effort to boost crop growth
“We believe that the concept is applicable to arid regions worldwide.” Mario Schmack, Murdoch University
by Ian Randall
Low-tech ‘Bubble-Greenhouses’ turn salt water into fresh water
They also create cool, humid conditions for better growth
Researchers are seeking partners to make prototype
Researchers in Australia are seeking to build a prototype ‘Bubble-Greenhouse’ that could provide remote, arid places with a low-tech, low-maintenance way to turn salt water into fresh water to grow food.
The engineers from Murdoch University, who published their study last month in the journal Desalination, estimate that a 150 square metre Bubble-Greenhouse could produce around eight cubic metres of fresh water and up to 30 kilograms of crops each day. The sealed structure would protect crops from insects and disease, while the technology should be relatively simple to implement and use in isolated areas, they say.
The Bubble-Greenhouse idea develops an existing seawater greenhouse concept, which uses the evaporation and condensation of salt water to produce fresh water for irrigation and to create a cool, humid environment inside a greenhouse, meaning crops need less water to grow.
The new approach moves the evaporation and condensation processes outside the greenhouse. Inside two water-filled ‘bubble columns’, streams of thousands of tiny bubbles create a large surface for water to evaporate or condense. A unique property of seawater prevents the small bubbles joining to form big bubbles, thus maintaining a large surface area.
The four educational booklets are separately designed for beginner, intermediate, advanced and young adult students, with an accompanying educator’s guide for teachers.
Originally produced in English to complement the exhibit on soils at the Smithsonian National Museum of Natural History, the materials have been translated into French, Spanish, Italian, Chinese, Arabic and Russian, and the content has been slightly adapted to suit the needs of different FAO member countries. All of the booklets are available for download on the FAO International Year of Soils website.
FAO is now collaborating with governments who wish to translate the materials into additional languages to be used in primary and secondary school curricula. Once finalized, all of the materials will be available online for free use by member countries, teachers and students, just in time for the beginning of the new school year in the Northern Hemisphere.
One of the most inspiring recent developments in the discussion about farming has been the shift from talking about “sustainable” agriculture to advocating for “regenerative” agriculture. Instead of seeking to be less bad, say a growing number of farmers and farming experts, the farming industry should be positioning itself to be good—to heal the harm being done to our planet.
In the UK, former natural history filmmaker Rebecca Hosking has been at the forefront of this conversation, returning to her parents’ family farm and rethinking its operations as a resilient, sustainable and regenerative “farm for the future.” That farm—which has become named The Village Farm—faces some fairly significant challenges in terms of soil conditions and topography, not least because previous management practices have degraded what was there. This from the Village Farm website explains more:
Training manual on household based pond aquaculture, homestead gardening and nutrition awareness
Currently many farming households face health and economic risks because of problems in malnutrition as a result of lack of knowledge and training, improved technologies and processes in farming. From the beginning of the CSISA-BD project, the World Fish Center has initiated introduction improved practices and technologies in rural farming to address malnutrition in farming households. In order to address the problem discussed, as a part of this project it has been felt there is a lack of skilled trainers and training materials. Based on field experience and existing training manuals, the WFC has developed training material and manuals on ‘Household Based Pond Aquaculture, Homestead Gardening and Nutrition Awareness with respect to the environment and socio-economic risks faced by fish farmers. These manuals have been developed for government and non-government training staff and fish farmers. During the project period the training staff and fsh farmers, it is expected that the manuals will be beneficial. Based on the experience in the field, the manuals will be further developed and enriched in future. It can be expected that various government and nongovernment training staff and persons will utilize this manual to assist in the development of human resources as well as fish production and thus contribute to the country’s overall economic development.
Fishponds facilitate natural resources management on small-scale farms in tropical developing countries.
A redefinition of the objectives for aquaculture development in tropical developing countries is presented. The common rationale to justify aquaculture development is that of fish production per se as a stand-alone enterprise. Efforts to link fish culture with livestock production by small-scale resource-poor farmers have not worked well because technology packages were proposed which did not consider their perspectives and resources. An alternative view is presented here, in which all the natural resources that can be managed by the fanner are considered. The fishpond, in most cases a newly introduced enterprise, can be integrated into on-going farm activities, relying largely on on-farm residues as pond inputs. In such farm systems, the fishpond can have a pivotal role in supporting other activities, e.g. water for dry-season gardening of vegetables, and increased production of existing crops with pond mud used for fertilization of nutrient-depleted fields. Farmers understand the importance and the benefits of improved management of their natural resources. This can be facilitated by small fishponds. They are entry points to better management of natural resources and are also environmental assets.
Scientists at the Korea Research Institute of Bioscience and Biotechnology developed a new technology that aims to prevent desertification using biotech crops. According to research leader Dr. Kwak Sang-soo, about 90 percent of desertification is due to poverty. “Overgrazing, damage to forests, and the inappropriate management of water and soil, stemming from the poverty of the local people, are core reasons for desertification. So, the cultivation of crops can be the most effective preventative measure,” he explains.
The team successfully planted biotech sweet potatoes in China‘s Kubichi Desert and Kazakhstan, two of the largest semi-arid areas in Northeast Asia. They are also decoding thegenome of sweet potatoes in collaboration with Chinese and Japanese researchers. The genome of sweet potato is harder to decode than the human genome, but they project that it will be completed in 2016.
Tech Developed to Prevent Desertification with Genetically- modified Sweet Potatoes
Researchers from the Korea Research Institute of Bioscience & Biotechnology are showing that biotechnology could be used to prevent desertification and solve environmental problems, food shortages, and poverty. The team studies crops, and plants, such as sweet potatoes and alfalfa. According to Dr. Kwak Sang-soo,“About 90 percent of desertification is caused by poverty. Overgrazing, damage to forests, and the inappropriate management of water and soil, stemming from the poverty of the local people, are core reasons for desertification. So, the cultivation of crops can be the most effective preventative measure.”The team has successfully grown genetically modified (GM) sweet potatoes in China’s Kubuchi Desert and Kazakhstan, two of the largest semi-arid areas in Northeast Asia. The team has also begun work, in conjunction with Chinese and Japanese researchers, to decode the genome of the sweet potato. “Our ultimate goal,” added Kwak,
I have been reading up on your blogs on sand dams. Very very interesting and very much in need in Southern Africa as well. I am looking to make a difference in South Africa and I hope that you will be able to assist me in the execution of my dream and vision of a better future for all in this beautiful country.
I am hoping that you will be able to guide me in the right direction. We are setting up projects to create jobs in small rural towns in the more arid areas of Southern Africa. We are looking at small towns with 80% unemployment rate and higher. The idea is to put together a workable and sustainable plan to create jobs and also address issues like alcohol and substance abuse. Big problems with foetal alcohol syndrome and we want to do our best to obliterate that.
I sat down and started putting small projects together to create work for women in particular. Bee keepers, handwork, leather shoes with African beading, wool products, mohair products, living gardens in handmade concrete boxes, etc.
Our main object though is to create sustainable income with harvesting a local declared weed for animal feed. What I would like to know: is it possible to change the climate in arid areas by planting drought resistant plants that can be used for food, fuel and animal feed. Will the plants be able to make a positive impact on the ground and the climate. I am looking at using plants to try and turnaround areas previously marked as desert and semi-desert areas back to useable fertile land that can be used for food crops.
I will really appreciate your input if possible.
RTM Project Support Administrator
British American Tobacco South Africa
My reply (Willem Van Cotthem)
Thanks for your message and congratulations for your efforts.
I will first try to answer your questions:
(1) Is it possible to change the climate in arid areas by planting drought resistant plants that can be used for food, fuel and animal feed?
In order to change the local climate in a significant way, one needs to cover up a desertlike environment with trees and shrubs. These will transpire a lot of water in the air and give sufficient shadow over the soil to limit evaporation of the soil moisture. Gradually the area will become less arid.
I see one immediate solution for South Africa, that is to start planting cuttings of the Elephant bush (spekboom,Portulacaria afra), a drought tolerant species that is widespread in the country and is favourite fodder for animals (elephants, antelopes, goats, sheep, etc.). It has a remarkable characteristic: little leaves falling on the soil start rooting with some moisture and give new plants, forming a real bush.
I would start with spekboom cuttings in a nursery and multiply constantly to be able to cover a large area.
One can also use a drought tolerant bamboo:
Oxytenanthera abyssinica, the savannah bamboo (see Google). It is a very hardy bamboo and can grow on poor soils. This fast growing species can also be grown from cuttings and rhizomes. People use it to make various types of local baskets for transporting produce, but the main use is as building material (scaffolding, house construction, fencing, even furniture). It could be used for soil erosion control and rehabilitation of degraded areas.
(2) Will the plants be able to make a positive impact on the ground and the climate? I am looking at using plants to try and turnaround areas previously marked as desert and semi-desert areas back to useable fertile land that can be used for food crops.
Growing plants always have a positive impact on the soil. As for the climate, it depends upon the density of the vegetation cover (one needs bushes or even a wood with trees).
Aiming at turning a desertlike area into fertile land is a rather difficult exercise. One of the well-known methods is densely seeding the land with leguminous species. Please read this article:
You will find a lot of interesting ideas, e.g. the use of cowpea (Vigna unguiculata), gum arabic tree (Acacia senegal), honeybush (Cyclopia), rooibos tea (Aspalathus linearis), groundnut (Arachis hypogea), etc.
Once (and not before) the effect of these leguminous species is significant, one can start to use the land for food crops.
However, I would like to recommend the set up of plantations of the spineless cactus Opuntia ficus-indica var. inermis (which means without spines). Please Google “nopales” to find sufficient information on the huge plantations in Central and South America, where billions of people are eating these cactus pads and fruits.
(3) My attention was taken to your project : “living gardens in handmade concrete boxes”.
This is extremely interesting, because it coincides with my continuous efforts to convince people to switch from classic gardening (food production in a kitchen garden) to “CONTAINER GARDENING”.
As you know, the main problem for gardeners is the quality of the soil (drought, lack of organic matter, pests, etc.).
Well, by growing vegetables and herbs in all sorts of containers (pots, buckets, bottles, plastic bags, sacks, barrels, etc.) one can avoid most of these gardening problems. Let me recommend to have a good look at my websites and Facebook pages concerning container gardening and you will discover numerous simple, cheap and efficient ideas for food production in arid, semi-arid and sub-humid regions.
MY WEBSITES AND FACEBOOK PAGES (Willem Van Cotthem)