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Aquaponics: The most significant agricultural development

Dave Clancy — Wed, 21 Apr 2010 13:46:10 +0000

Last month, I discussed the necessity of food production mechanism in urban centers. As city populations swell and the as yet unknown consequences of climate change slowly materialize, it is becoming apparent that issues of food security will develop into major challenges not just for nations of the developing world, but for all humanity.

This month, I will examine one of the most significant agricultural development of our time which, if implemented competently could provide a solution to future food security challenges. The development of which I speak is known as Aquaponics. In it’s most basic form, Aquaponics is the production of fish and plants within a controlled environment that in many ways replicates the biological processes and interactions found in the natural world. Plants are fed nitrogen rich fish waste while the fish consume (among other things) excess plant biomass.

This process, although not entirely novel (The Mayans and Babylonians have got us on that one) represents a significant improvement upon conventional hydroponic and aquacultural practices for a number of reasons. First, combining both fish and plant production into one system maximizes output while utilizing a minimal amount of space, time and resources. This process is ideal for the urban environment as both fish protein and vegetables are produced within a limited area, providing residents with access to the fundamental nutritional requirements they need right at their doorstep.Secondly, by feeding fish effluent to plants the producer is able to turn an otherwise costly waste stream into valuble organic plant food. Finally, producing food within city limits will allow urban dwellers to prepare for and buffer against any disruptions in existing food supply infrastructure.

As world events have recently illustrated quite poingnently, anything can and often does happen. (Just ask any recent European air traveller) Although by no means a complete solution in and of itself, Aquaponic sysems represent an important cornerstone in the development of future food security infrastructure and when integrated into a systme featuring renewable energy sources and dedicated policy initiatives, Aquaponics has the potential to provide us all with a little more security in what has consistently proven to be an ever dynamic and unpredictable world.

Sources:

Nelson and Pade: North American leaders in Aquaponic technology. They publish the only magazine on Aquaponics and provide classes and consultation to startup projects.

http://www.aquaponics.com/index.php?_route_=index.htm

University of the Virgin Islands Agricultural Experiment Station : Headed by Dr. James Rackocy, this is the worlds leading programme dedicated to to the study of Aquaponics.

http://www.uvi.edu/sites/uvi/Pages/AES-Aquaculture-Home.aspx?s=AC

Ocean Fertilization: A viable option to mitigate global warming

Sarfaraz Nasir — Thu, 08 Apr 2010 14:51:10 +0000

One of the recent geoengineering methods caught attention was the ocean fertilization. Some scientists went as far as claiming that the ocean fertilization could be the fix for rising global warming concerns around the world. There have been many studies on using the ocean fertilization as a way to reduce greenhouse gases from the atmosphere that contribute to the global warming. Some of the recent findings concluded that ocean fertilization may not be able to help reduce carbon dioxide from the atmosphere as much as previously thought. Additionally, many challenges still remain before implementing ocean fertilization process on a wide scale. Although the process may not be perfect, ocean fertilization does sound like a promising technology that can help mitigate the global warming at certain level.

A schematic representation of the biological pump.

Photo Source: Courtesy of Z. Johnson and Nature Magazine, October 12, 2001.

The ocean is a natural absorber of excess carbon dioxide. Scientists estimates that majority of the carbon dioxide produced by burning of fossil fuels is absorbed by the oceans. The ocean fertilization is a geoengineering method of purposely introducing iron and other nutrients to sequester carbon dioxide from the atmosphere without affecting the marine life. The main objective of the ocean fertilization process is to increase the rate at which ocean absorbs carbon dioxide. Therefore, ocean areas that are nutrient deficient can be good candidates to implement the ocean nourishment method to help reduce climate change effects in surrounding areas.

Ocean fertilization is not as simple as it sounds and has drawbacks. Some of the issues with ocean fertilization include the lack of information on impacts of long term ocean fertilization and regulatory framework for the process. The process could potentially increase production of other greenhouse gases such nitrogen oxide thus, nullifying the positive effects of absorbing carbon dioxide from the atmosphere. The ocean fertilization may also reduce oxygen level at the deep ocean causing issues for fisheries and other marine organisms. These risks and uncertainties of ocean fertilization have caused concerns among environmentalists and scientists. Regulatory framework especially beyond national jurisdiction is not very well defined when it comes to ocean fertilization. As a result, the scope of wide scale implementation or study is limited.

Conclusion:

Due to the rising population and increased use of fossil fuel, Carbon Dioxide is being emitted at an unprecedented levels and the rate is only accelerating. Reducing Carbon Dioxide emission must be international priority. Ocean fertilization may not be the ultimate fix to solve the global warming issue. However, ocean fertilization as a mitigation option certainly can be used along with other mitigation strategies.

Source: Robin Warner

Below is a video that will provide some more information about ocean fertilization:

Pros and Cons of Renewable and Nonrenewable Energy Sources

Sarfaraz Nasir — Tue, 09 Feb 2010 17:49:27 +0000

The world is moving towards renewable energy sources. Yet, there are many people who still advocate on using the traditional nonrenewable energy sources. Many of the vocal groups on both sides seem to have commercial benefits in supporting their respective energy sources. In the midst of commerce, general public are blind sided. Understanding advantages and disadvantages of renewable and nonrenewable energy sources will help make the correct individual decision.

Here are the pros and cons of three nonrenewable and three renewable energy sources:

Nonrenewable energy sources:

Energy Type	Advantages	Disadvantages
Oil	High net energy yield Easily transported within and between countries Low land use Technology is well developed Efficient distribution system in place	Causes air pollution when burned Releases CO2 when burned Increases dependency on countries that are major oil producers Causes moderate water pollution Supply is decreasing
Nuclear	Moderate land use Large fuel supply Lower Co2 emission Low environmental effect while running without any accidents	Higher cost Low net energy yield Subject to terrorist attacks Spreads knowledge and technology for building nuclear weapons
Natural Gas	High net energy yield Less air pollution than fossil fuel Lower Co2 emission than fossil fuel Moderate environmental impact Low land use	Possibility of leaking Methane from the pipelines Lacks portability Releases CO2 when burned Extraction side effects Requires expensive pipelines Highly combustible and methane explosions are possible

Renewable energy sources:

Energy Type	Advantages	Disadvantages
Solar	Reduces dependency on fossil fuel and coal Renewable, endless supply that belongs to no one Low environmental effect No Co2 emission Can be constructed faster Can provide electricity to poor and remote people	Low efficiency High costs Need access to sun most of the time Energy has to be stored in batteries, hydrogen, water or other matter
Wind Power	High efficiency Very low environmental effect No CO2 emission Quick construction Does not produce wastes	Wind turbines are noisy Requires steady wind Visual pollution—Many people disapprove the idea to install because it can disrupt the landscape High possibility of killing birds Low energy production
Biomass	Can make use of agricultural, timber, and urban wastes Moderate costs Easy to convert to a high energy portable fuel such as alcohol or gas Very low in sulphur reducing the production of acid rain	Moderate to high environmental effect Soil erosion, water pollution, and loss of wildlife habitat More expensive than conventional fossil fuel A less concentrated form of energy, making it less efficient

Sustainable Agriculture: A pragmatic solution

Admin — Tue, 12 Jan 2010 14:33:11 +0000

The sustainability means meeting the present needs without compromising on the ability of future generations to meet their needs.

The rising population is making the food shortage issue more challenging. Millions of people around the world do not have access to adequate food. Although the food shortage issue for now seems to be contained only in poor countries, it could wide spread easily if necessary steps are not taken in the right direction. Simply, increasing farming is not realistic.

One of the solutions to meet food requirements without compromising on environmental health and economic profitability is; using sustainable agriculture method to produce food. The sustainable agriculture techniques can produce food by reducing throughput resources and working more with nature.

Using of low-input agriculture also known as organic farming can significantly help produce more sustainably. Organic farming uses technologies to increase yields, control pests, and build soil fertility. It also relies more on perennial crops reducing the need of yearly cultivation of land.

The sustainable agriculture method increases availability of food as it could double or triple the food production. More poor people can get access to food. Future irrigation water cutbacks as a result of aquifer depletion. The sustainable agriculture method helps reducing the aquifer depletion and increase grain harvest. In addition, organic farming increases irrigation efficiency by building active soils with high content of organic matter that has positive effects on soil and water holding capacity, including groundwater recharge and decreased run-offs.

The sustainable agriculture is a joint effort by the farmers, policymakers, researchers, retailers, consumers, and others involved in the food chain process. Everyone has to make efforts to achieve the common goal of producing sufficient food with minimum environmental impact. Are you ready to play your part?

Producing Meat Sustainably

Sarfaraz Nasir — Sat, 02 Jan 2010 18:05:14 +0000

According to the USDA, beef consumption in the United States alone in 2008 was 27.3 billion pounds. As the population and demand for meat grow around the world, producing meat sustainably will be a necessity. People need to shift intake of certain animal proteins. For instance; lamb, goat, and beef are grain-inefficient. Shifting towards more grain-efficient animal proteins such as chicken and fish can help produce meat more sustainably.

The grain-inefficient livestock graze on rangeland use resources that humans can not eat, and most of the land used in livestock grazing is not suitable for growing crops. Shifting to grain-efficient animals can help reduce the overgrazing. Thus reducing the environmental effects caused by overgrazing of livestock. The grain-efficient animals such as chicken requires less space and food compared to beef and lamb.

Harvesting fish and shellfish can also increase the meat production. Advanced technologies and methods can be used to collect and store more fish. However, the increased dependence of fish and shellfish has its own disadvantages. It can cause over fishing that can result in commercial extinction of some fish and shellfish disrupting aquatic life. Some of the methods used in fishing can potentially destroy the ocean floor habitat. Over fishing and degradation of ocean floor habitat can result in lower overall yields. Finally, trying to catch more fish can also trap and kill unwanted fish and marine mammals such as Dolphins and Seals. This can create unbalance in the aquatic life in the ocean.

You may have already heard that eating meat is not eco friendly. However, everyone may not like the idea of being completely a vegetarian. In such case, we should at least try to adapt sustainable meat production to reduce our impact on the environment.

Soil Degradation: Causes, consequences, and solutions

Admin — Mon, 21 Dec 2009 16:47:27 +0000

Global warming and climate change has taken over the world, ignoring the fact that the soil degradation is the most important environmental issue. Rising population is putting additional pressure on the soil degradation around the world. People are unaware of the economic, health, and environmental impacts of the soil degradation.

What is soil degradation?

Soil degradation is an evolution that occurs when soil loses its quality and productivity. Human activities and natural disasters are primarily responsible for the soil degradation.

There are three main types of soil degradation: soil erosion, Desertification, and Salinization. Let’s review the causes, consequences, and solutions for each types of soil degradation.

Soil Erosion

Causes of soil erosion

Water can cause soil erosion. Rainfall is an example of water causing soil erosion.
Wind can also cause soil erosion. The lack of permanent vegetation cover in certain locations can cause soil erosion due to the wind.
Human activities such as farming, logging, and constructions also cause soil erosion.

Consequences of soil erosion

Soil erosion can lead to poor crop growth and yield reductions in areas of fields.
Loss of soil fertility through depletion of plant nutrients in top soil.
Soil quality, structure, stability and texture can be affected by the loss of soil.
Eroded soil can ends up as sediment in nearby surface waters where it can pollute water that could potentially kill fish and other species.

Solutions for reducing soil erosion

Actively participate in the soil conservation programs.
Maintain a vegetation cover especially in the vulnerable areas (i.e. steep slopes, arid areas).
Maintain livestock grazing rate to prevent overgrazing.
In cultivation areas, crop rotation should be used to prevent the soil becoming exhausted.

Desertification

Causes of desertification

Natural climate change that causes prolonged drought.
Human activities that reduce or degrade top soil.
Increased population and livestock pressure on marginal lands accelerates desertification.
Deforestation

Consequences of desertification

Economic loses
Lower living standards
Major threat to biodiversity
Prolonged droughts

Solutions to reduce desertification

Reduce overgrazing and deforestation.
Limit human activities such as destructive forms of planting, irrigation, and mining that leave soil barren.
Plant more trees and grasses to anchor soil and hold water.
Plant leguminous plants that extract nitrogen from the air and fix it in the soil to restore fertility.

Salinization

Causes of Salinization

High level of salt in the soils
Over cultivation
Irrigation mismanagement
Climate trends that favor accumulation

Consequences of Salinization

Stunts crop growth
Lowers crop yields
Destroys fertility and plants
Damage to infrastructure (i.e. roads, bricks etc.)
Reduction of water quality

Solutions to reduce Salinization

Reduce irrigation
Switch to salt-tolerant crops
Use humic acids to fix anions and cations and eliminate them from the root region of the plants.

Soil conservation is part of living green. Do what you can to protect the soil and create awareness.