Gdome By Great Ideas Association

GDome Greenhouse for the future

Done By: Ngo Hoang Gia – Quek Keng Yong – Han Qiao Raffles Institution (Junior College)

Supervised By: Mr. Se Kuan Pin

Contents Contents ..................................................................................................................................... 3 Table of Figures ......................................................................................................................... 4 Abstract ...................................................................................................................................... 5 1. Introduction ........................................................................................................................ 6 1.1. Problem Identification – The Food Crisis .................................................................. 6 1.1.1. Diminishing Arable Land .................................................................................. 6 1.1.2.

Saturation of Productivity .................................................................................. 7

1.2. Solution – GDome ..................................................................................................... 7 1.2.1. Location – Tropical Coastal Region .................................................................. 7 1.2.2. 2.

Engineering Goals .............................................................................................. 8

Dome .................................................................................................................................. 8 2.1. Structure: .................................................................................................................... 8 2.1.1. Overall structure: ............................................................................................... 8 2.1.2.

Building blocks: ................................................................................................. 9

2.1.3.

Material: ........................................................................................................... 11

2.1.4.

Cost: ................................................................................................................. 11

2.1.5.

Why a dome? ................................................................................................... 11

2.1.5.1. Aerodynamics: ................................................................................................. 11 2.1.5.2. No need of extensive supporting structure: ..................................................... 12 2.2. Construction prototype: ........................................................................................... 13 2.3. Algae cultivation: ..................................................................................................... 15 2.3.1. Advantages of algae biofuel............................................................................. 15

3.

2.3.2.

Methodology .................................................................................................... 15

2.3.3.

Potential Yield ................................................................................................. 15

Irrigation: ......................................................................................................................... 16 3.1. Irrigation- Design: .................................................................................................... 16 3.2. Irrigation- Process: ................................................................................................... 19 4. Ventilation........................................................................................................................ 19 4.1. Ventilation- Design: ................................................................................................. 19 4.2. Ventilation- Process: ................................................................................................ 22 5. Crop: ................................................................................................................................ 23 6. External facilities: ............................................................................................................ 26 6.1. Water collection from car tires: ............................................................................... 26 6.2. Power supply:........................................................................................................... 28 7. Application, Weaknesses and Future Direction ............................................................... 28 7.1. Application:.............................................................................................................. 28 7.2. Weaknesses: ............................................................................................................. 29 7.3. Future direction: ....................................................................................................... 29 8. Conclusion: ...................................................................................................................... 29 9. Bibliography .................................................................................................................... 30

Table of Figures Figure 1: Overview of the dome ............................................................................................... 8 Figure 2: Similar measurements of edges in geodesic structure............................................... 9 Figure 3: Gaps between building blocks ................................................................................. 10 Figure 4: Overview of the building blocks ............................................................................... 10 Figure 5: Aerodynamic shape of the dome ............................................................................. 12 Figure 6: the dome limits the use of supporting structure...................................................... 13 Figure 7: Construction Prototype ............................................................................................ 14 Figure 8: Rainwater collection ................................................................................................. 16 Figure 9: Regulation of water in the inner patch of the GDome ............................................. 16 Figure 10: Division of land inside the dome ............................................................................ 17 Figure 11: Water absorption into the soil by osmosis ............................................................. 18 Figure 12: Operation of the irrigation system ......................................................................... 19 Figure 13: The arrangement of the ventilation fan in the dome ............................................. 20 Figure 14: Functioning of the ventilating unit ......................................................................... 20 Figure 15: Carboard evaporator and polyethene condenser used in the Seawater Greenhouse Project ...................................................................................................................................... 21 Figure 16: Operation of the ventilating system ....................................................................... 22 Figure 17: The air flow around the dome ................................................................................ 22 Figure 18: First cycle crop ........................................................................................................ 23 Figure 19: Plants distribution in the second cycle ................................................................... 24 Figure 20: The “three sisters” crop .......................................................................................... 25 Figure 21: water collection from car tyres............................................................................... 27

Abstract This project aims to solve the problem of world hunger, depleting land and water resource for agriculture in the future by designing a high-yield and sustainable farming method tailored to tackle such issues. The long-term performance and economic aspects of various greenhouse systems were studied and used to formulate a novel greenhouse design which delivers stable yields, costs little to operate and capable of resisting weather elements. Consisting of innovative features and cutting-edge engineering technology, our proposed product, the GDome farming system, will fill the stomachs of hungry people worldwide, especially in the face of future food and water crisis.

1. Introduction 1.1. Problem Identification – The Food Crisis "Without a second agricultural revolution that targets water, a "blue revolution", then the gains of the past generation could be wiped out as rivers run dry. Underground water reserves are exhausted, and fields are caked in salt" (Pearce, When the rivers run dry, 2006) We believe that a food crisis will occur in the near future. With global warming aggravating and adversely affecting crop yields, appalling inefficiency in the utilization of natural resources and over-consumption in developed countries, coupled with an ever burgeoning global population, the threat of global food scarcity looms near (Brown, 2005). In fact, between 2002 and 2004, world grain stock has plummeted by 128 million tons, or 31.9% (United States Department of Agriculture, 2009). In averting this imminent catastrophe, it is imperative that we develop techniques to deal with current food shortages in developing countries. The underlying problems of food shortages are mainly the reduction of arable land and saturation of productivity of farms (Brown, 2005). 1.1.1. Diminishing Arable Land In contrast to the steady 70 million annual population growth (United Nations Population Division, 2009), the area available for grain production has fallen by 60 million hectares from 1981 to 2004 (United States Department of Agriculture, 2009). If current projections are accurate, the area of arable land per person will shrink by one third within the next 50 years (Brown, 2005). Such drastic change could be accounted for by the following factors. Firstly, the accelerated pace of global warming has pushed temperature beyond the limit of sustaining agricultural activities. Given the projected temperature increase of 5.2 C for the next century (Sokolov, et al., 2009), global food production will be significantly affected because the yield potential of crops depends heavily on attaining the desired temperature (Lobell & Asner, 2003). Coupled with the effect of concentrated warming (Intergovernmental Panel on Climate Change, 2001), the amount of arable land in temperate countries would be significantly reduced due to harsh environment conditions. In addition, overexploitation of fertile soil to increase productivity invariably leads to soil erosion and desertification due to poor management. For example, in Nigeria, overgrazing and overplowing have been identified by experts as the root causes for the annual desertification of 351,000 hectares of grassland and cropland (Government of Nigeria, 1999). In other words, our attempt to recover lost land by increasing productivity has lead to further loss of arable land, forming a vicious cycle that traps global food production.

Every year, millions of hectares of cropland are also being converted into other nonagricultural uses, such as residential blocks, industrial plants, infrastructural constructions, and oil farming (Brown, 2005). These activities are carried out for their economic benefits without internalizing the external costs of transforming cropland. 1.1.2. Saturation of Productivity In order to feed the booming population, Africa has to triple its food production by 2050 (Mahmood, 2008). However, world grainland productivity has stagnated since 2000, with an average annual growth less than 0.1% (United States Department of Agriculture, 2009). This is due to both the diminishing effect of hybrid/GM grain varieties on maximizing yield potential and the lack of natural resources as input (Evans, 1993). More specifically, the bottleneck in today’s agricultural production is the lack of fresh water and natural fertilizers that will fully realize the yield potential of crops grown. In many countries, extensive wasteful irrigation has depleted aquifers, significantly reducing crop yield (Pearce, When the Rivers Run Dry: Water - The Defining Crisis of the Twenty-First Century, 2006). Coupled with the increasing competition for fresh water from the cities, many croplands are facing the risk of having their water supply cut off soon (Brown, 2005). The use of chemical fertilizers has also cultivated a sense of dependency on raising external inputs for higher yield (Smriga, 2002). With increasingly extensive usage, not only will the inherent fertility of the soil be lost, the fun of sustainable farming will also be replaced by the stress of commercial agriculture (Logsdon, 2009).

1.2. Solution – GDome From the problems stated above, it is evident that the solution to increasing the global food production needs to fulfill the following criteria. 1. 2. 3. 4. 5. 6.

Enable farming in otherwise impossible regions Create a desirable local climate Practice sustainable farming Make reasonable profits Manage resources efficiently Provide protection from emergency

A viable way of achieving this would be through the implementation of a novel greenhouse. Presenting to you, GDome – Greenhouse for the futre. 1.2.1. Location – Tropical Coastal Region The tropical coastal region is an ideal place for farming because of abundant sunlight, water, and organic matter. Sunlight provides plants with energy for photosynthesis while at the

same time keeping the environment warm. Water is essential to survival while organic matter is the natural fertilizer that keeps the soil fertile. However, there are several limiting factors that prevent effective farming from taking place. Firstly, the both water and soil are salinated, though at different degrees, undermining the survival of crops. The existence of sea breeze and land breeze or even tropical storms will also threaten the survival of young and fragile seedlings. 1.2.2. Engineering Goals GDome will aim to counter the limitations mentioned above and fulfill the aims described earlier. This can be achieved by fulfilling the following engineering goals. 1. 2. 3. 4. 5.

Structurally strong to withstand extreme weather Substantial thermal insulation to prevent temperature fluctuations Easily transported and constructible on site Harness forces of nature to generate electricity Efficient water management system to counter unpredictable rainfall

2. Dome 2.1. Structure: 2.1.1. Overall structure:

(3) Dome

(1) Slope (2) Water storage tanks

(GIA)

Figure 1: Overview of the dome

A prototype structure that we illustrate above is a 51v geodesic dome consisting of 2885 triangular “blocks”

In rain, rainwater flows gently down the slope surrounding the dome to be collected in water storage tanks around its perimeter. The water storage tanks around the dome’s perimeter serve a dual purpose- to store water and provide support for the base of the dome.

(Mueller, 2009) Figure 2: Similar measurements of edges in geodesic structure

2.1.2. Building blocks: Our geodesic dome consists of a large number of similar blocks. Figure 2 shows the different edges in the geodesic structure that have the same length (which are labelled with the same letters) (Mueller, 2009). This particular feature reduces the number of individual designs for the blocks, making the dome suitable for mass-production. Although the dimensions of the blocks are similar, they are not identical. There are slight differences in dimensions of different blocks due to the geometric nature of the geodesic structure. To overcome this problem, we expect the blocks not to packed together, but there should be tiny gaps in between blocks to compensate the thermal expansion of the blocks, as well as to reduce the number of different sized blocks that need to be produced.

Gap

(GIA) Figure 3: Gaps between building blocks

The hollow interior of some blocks are filled with water. To be specific, the blocks around the base contain plastic bags in which high-lipid algae strains are grown. We shall come back to this point later.

Algae bag is (1) to be put inside (2)

(GIA) Figure 4: Overview of the building blocks

2.1.3. Material: After a thorough evaluation of a wide selection of transparent construction material ranging from ETFE (Ethylene tetrafluoroethylene) to Polyethylene, we have settled on Acrylic Glass (Poly (methyl methacrylate)) as the construction material for dome. Acrylic glass is the material of choice for external structures due to its environmental stability compared to other plastics. Furthermore, it transmits up to 92% of visible light and gives a reflection of about 4% from each of its surfaces on account of its refractive index of 1.4893 to 1.4899. One important application of acrylic glass is to construct large-scale commercial aquariums. The invention of acrylic glass enabled architects to build big aquariums such as Tokyo Sea Life Park. These features of acrylic glass make it highly suitable for our project 2.1.4. Cost: The price of acrylic glass is USD $2.35 per kg, or USD $2700 per cubic metre. Building our dome will require 15.6 cubic metres of acrylic, thus around USD $42000 is required for the construction of one dome. Although this seems to be a very steep price, it must be taken into consideration that after the dome is built, the maintenance costs will be very low. 2.1.5. Why a dome? 2.1.5.1.

Aerodynamics:

(GIA) Figure 5: Aerodynamic shape of the dome

A sphere encloses maximum volume with minimal surface area. Since a geodesic dome is part of a sphere, it hence possesses the same property. With minimal surface area, geodesic domes have excellent aerodynamic properties and indeed, they have been proven to be capable of withstanding strong winds and hurricanes with minimal damage. 2.1.5.2.

No need of extensive supporting structure:

(1)

(2)

(3)

(1): distribution of force. (2): the force exerting by the surrounding soil on the dome to hold the base of the dome together. (3): blocks containing algae.

(GIA) Figure 6: the dome limits the use of supporting structure

The geodesic structure ensures that the weight of the structure is distributed down to the base of the dome. The forces exerting on other parts of the dome is limited. The force exerted by the surrounding ground on the dome, along with the resistive forces provided by the heavy water tanks, holds the base of the dome together. Blocks near the base of the dome are used to grow algae, which also provide stability.

2.2. Construction prototype: The interior of our GDome contains the unconventional feature of a downward sloped floor. Figure 7 shows the proposed building process of the system.

1. Original landscape

2. Removal of land

3. Installation of the irrigation system of the inner patch

4. Making the inner patch Isolated from the outer patch

5. Installing the water storage tanks and prepare the base of the dome

6. Piecing the building blocks together.

(GIA) Figure 7: Construction Prototype

Potential setbacks: -

Since the dome is located lower than the surround land, there will be sand and soil sliding down the slope. However, this amount of soil and sand may further hold the base of the dome together.

-

The low location of the dome may make it highly vulnerable to flooding. However, as we intend to have GDome built in arid places, this danger may be reduced. Moreover, depending on the geographical features of the place, there may be no need to locate the dome lower than the surrounding area.

2.3. Algae cultivation: The panels which comprise the G-dome also serve as photobioreactors in which microalgae with high oil content (Scenedesmus dimorphus) are cultivated. The algae will be collected and processed into biofuel which can be used to power local vehicles or electricity generators. 2.3.1. Advantages of algae biofuel Benefits of using algae to produce biofuel: Algae yields more oil per unit of land than conventional crops, and its growth will not affect freshwater or food supply since it can be grown using saltwater (Hartman, 2008). 2.3.2. Methodology The medium in which the algae is grown will be UV-processed seawater with small amounts of nutrients added. Carbon dioxide produced from the generator powering the farm will be fed into the photobioreactor. This maximizes the efficiency of the photobioreactor and allows the algae to grow at the fastest rate. (This also makes the farm carbon-neutral, since its C02 emissions are reabsorbed back into the system) The lifespan of the algae grown under these conditions is slightly more than one week, so the algae will be harvested on a weekly basis. 2.3.3. Potential Yield The maximum volume of algae solution the G-dome can hold is 650 cubic metres. Taking into consideration the 0.20 dry algae factor (percentage of algae cells in relation to the media in which it is cultured) and the 0.40 lipid factor (percentage of vegetable oils in relation to the algae cells required to get it) (Energy from Algae Presents an Opportunity You Cannot Afford to Ignore), we can potentially obtain 200 cubic metres, or 200 000 litres of oil with which to produce biofuel in a month (in which 4 harvests are made) . It is highly unlikely that there will be local facilities to convert this oil into biofuel, but this oil can be sold by the local community to provide them with a source of income

3. Irrigation: 3.1. Irrigation- Design:

(1)

(GIA) Figure 8: Rainwater collection

Rain water incident on the dome as well as the perimeter collection area flows downwards and is collected inside the water storage tanks.

Isolating layer (3) (2) (GIA) Figure 9: Regulation of water in the inner patch of the GDome

From the water tanks, the stored water flows along the pipes in the sloping floor, into the grid inside the central section of the dome. The pipes are made of recycled materials such as bicycle pipes in order to minimize environmental impact (When the rivers run dry).

The inner patch is isolated from the surrounding land by ETFE to limit the water loss into the

Isolating layer InnerInner patch patch

Outer patch

(GIA) Figure 10: Division of land inside the dome

surrounding. The inner patch is meant for more plants that require more water.

The pipers will also run on the ground of the outer patch. The water is used in the outer patch in the drop-wise manner.

Soil

(4)

(3) (2)

(GIA) Figure 11: Water absorption into the soil by osmosis

(1) shows the flow of the water down the slope. (2) shows the flow of water up the capillaries. (3) shows the flow of water into the soil by osmosis. The water from the water tank will be allowed to flow in the pipes when the farmers deem necessary (the moisture of the soil may be monitored by sensors in the ground of the inner patch).

3.2. Irrigation- Process:

(3)

(1) (2) (GIA)

Figure 12: Operation of the irrigation system

(1): water is collected into the water storage tanks once it rains. (2): water runs down the pipe due to gravitation force (this may be assisted limitedly by pumps) when the farmers deem necessary. (3): water used for inner patch is led from the bottom up. Therefore, water is only supplied just enough for the roots, limit the amount of water tend to be wasted with traditional topdown watering method. The isolated dome and the most air inside the dome limits the evaporation of water from the plants. Overall, the amount of water used is limited.

4. Ventilation 4.1. Ventilation- Design:

Building block

Fan

(GIA) Figure 13: The arrangement of the ventilation fan in the dome

One addition to the dome’s construction are ventilation fans. The ventilation fan is built in a pentagonal block in order to fit into the dome. The fans lie flat on the surface of the wall as shown in Figure 13 to minimize the dome’s aerodynamic resistance.

Condenser

Evaporator 2 Evaporator 1 Fresh water (GIA) Figure 14: Functioning of the ventilating unit

The cooling and ventilation system (a unit of which is shown in Figure 14) is used to maintain optimal growing conditions for the plants inside our dome. (Paton & Davies, 2006)

(Ryadh, 2006) Figure 15: Carboard evaporator and polyethene condenser used in the Seawater Greenhouse Project

4.2. Ventilation- Process:

(2)

(1)

GIA(2009) Figure 16: Operation of the ventilating system

(1) The operating fans take in the cool, moist sea breeze in the morning. The evaporator also ensures that the air taken in is kept moist. (2) The fans on the opposite side expel hot air. Due to the shape of the geodesic structure, the air moving on the surface of the dome will be faster than the still air inside the dome. By Bernoulli’s effect, the pressure outside will be lower than the pressure inside the dome, leading to air will be drawn out of the dome on the other side.

(1)

(GIA) Figure 17: The air flow around the dome

On the dome, the fans are spread across its surface, thus being able to harness the wind from any direction through alternating the direction of rotation of opposing pairs of fans.

5. Crop: First Cycle

Sorghum, Millet, Cassava

(GIA) Figure 18: First cycle crop

During the first crop cycle, soil is infertile and water is scarce. Hence, the entire GDome will be used to grow common and resilient crops such as sorghum, millet and cassava. These crops can thrive in both drought and flood as long as the soil temperature is kept around 20o C (Carter, et al., 2000) (Doggett, 1995). Crop density has to be kept low to prevent malnutrition. One possible approach is to plant in radial rows of 0.7m-1m apart using 3 kg of seeds per acre (black lines in figure 18) (Logsdon, 2009). After the crops are harvested, the large amount of residue will be buried in the soil to act as fertilizers for the next cycle. Second Cycle

Maize, Squash, Soybean Legumes

(GIA) Figure 19: Plants distribution in the second cycle

: During the second cycle, fertility of the soil has improved and some water has been collected in the containers. Hence, the inner patch will be used to grow Three Sister Crops – maize, squash and soybeans. These crops are of high nutritious value and can complement the growth of one another. The recommended approach is to plant them in alternating mounds (Figure 20) with several seeds sowed in each mound. Squash and soybeans will be planted only after maize has grown 15cm in height (Eames-Sheavly, 1993; Formiga, Celebrate the Three Sisters: corn, beans and squash, 2009).

(Formiga, Celebrate the Three Sisters: Corn, Beans and Squash) Figure 20: The “three sisters” crop

(Formiga, Celebrate the Three Sisters: Corn, Beans and Squash) The outer patch will be used to grow different kinds of legumes in order to fix the nitrogen in the soil in preparation for the next crop cycle. The seeds will be sowed in places that have been harvested before and with minimal ploughing of the land (black lines in figure 18). This ensures that the structure of the soil is not destroyed which in turn facilitates crop growth (Winter, 1981; Bridges, 1979; Janick, Schery, Woods, & Ruttan, 1981). Third Cycle

The inner patch will continue to grow Three Sisters Crops. The outer patch will be switched back to production of sorghum, millet, and cassava. Nth Cycle After repeating 2nd and 3rd cycle for 5-7 years, the fertility of the land would have been improved. It is now able to sustain agricultural activities without external support but protection from extreme weather conditions is still needed. Hence, we will start planting Acacia Albida trees which not only offers protection but also enhances productivity of the crops grown underneath it (U.S. Congress, Office of Technology Assessment, 1988). The purpose of having this plant is to ensure long-term self-sustained fertility of the patch of land. A total of 5 Acacia trees will be planted at the junction between the inner and outer patches, taking the corners and the centre of a square. When fully grown, they would cover most of the fertile areas (Irvine, 1961). After approximately 4 years of growth, these trees would have reached the height limit of GDome (Duke, 1997). GDome will then be disassembled and reconstructed at a neighbouring area to fix the next patch of soil.

Soil fixation (Winter, 1981; California Fertilizer Foundation; Bridges, 1979) Problem Lack of minerals

Solution Conduct a soil test and apply chemical fertilizers appropriately once before the first cycle Completely irrigate the soil with fresh water once before the first cycle Apply lime or sulphur to increase or decrease pH respectively

Excess salinity Abnormal pH

6. External facilities: 6.1. Water collection from car tires: Due to the scarcity of water, we implement means to collect water so as to make the system well-rounded.

Car tire Water droplets

Water container

Wet sand

(GIA) Figure 21: water collection from car tyres

In areas where car tires pose an environmental threat, (Loxton, 2003) instead of burning these tires, they can be used to collect water for agricultural use. The hygroscopic structure of the car tire traps the water vapor in the inside and prevents the water from evaporating away. We plan to place many car tires at near the water line. At high tide (preferably at night as what happen in many regions in Asia), the seawater will soak up the sand around these tires. During the daylight, the water in the sands will be heated up and evaporate. The water vapor is trapped inside the car tires and increase the humidity inside the car tires until water droplets is condensed. The car tires may be painted in white so as to keep the inner surface of the car tire cool. With a large number of car tires, we hope that the amount of water collected can be appreciable. Potential setback: - There are concerns over the leaking of toxic materials in the tires to the environment in the long term for certain types of car tyres, especially in the hot and high saltcontented condition. We hope that a suitable coating can help preventing such leaking. - The car tires need to be cleaned and painted before use, which will pose an overhead cost. - The car tires can affect the scenery of the region.

6.2. Power supply: To operate the ventilation fans and seawater pumps, a supply of electricity is required. This electricity will be obtained from the combustion of the algae biofuel produced, supported by an array of solar panels possibly built into the perimeter of the dome. Our self-sustained power supply contributes towards minimizing environmental impact

7. Application, Weaknesses and Future Direction 7.1. Application: We have already targeted a number of potential locations that this farming model should be implemented. Firstly, coastal regions that a similar concept, the “Seawater Greenhouse” has already deemed to be suitable, such as Tenerife, the UAE and Oman are good candidates. Moreover, there are many coastal areas in Asia with unfavorable environmental conditions, deficient in freshwater, and on top of this, disaster prone, for example, coastal provinces in Vietnam and Indonesia that were affected recently by the Ketsana typhoon. These types of disasters wipe out the crops and infrastructure, crippling the local farming economy. In the future, with extreme weather conditions likely to afflict the coasts in many countries, a strong and sustainable model for farming will be necessary. The high investment in the GDome may be insignificant, compared to the cost saving from its extremely long-term operation which is unaffected by the occurrence of natural disasters. The food produced in our GDome is not the tastiest, thus demand for it will probably be low in developed countries. However, with water and arable land becoming more and more scarce, even the rich may have to change their eating habits towards foods that require less water for cultivation (For example, 90% of freshwater in Asia is used in agriculture while 50% of that is used in rice production). One ideal region in which to establish this new mindset is Asia (Bouman, 2001).

7.2. Weaknesses: The operation of the GDome requires a certain level of technical knowledge. We have chosen to focus on the Asia region since the higher level of education and availability of infrastructure in Asia can help the implementation of GDome. With a rapidly expanding population, Asia requires a solution for ensuring food security the most. - The initial fixed cost in the construction of the dome is high. This cost can only be recouped over a long period of time, which may deter some investors from supporting our scheme - Our solution is a system involving many components. The system requires the seamless operation of all the components to be sustainable. Therefore, studies in different fields have to be carried out, especially the geographical features of the region. One thing to note is that our idea is purely based on secondary research without any actual experiments being carried out. We anticipate that many problems and setbacks will arise if the idea is ever implemented in reality. The advancement of new technology is hoped to resolve some of those concerns. Nonetheless, we hope that if GDome is ever put into real practice, the model can be further improved. -

7.3. Future direction: We envision the use of GDomes on a large scale as a means to improve the environmental conin many areas. After removing the GDomes, the lands would have been made more fertile to grow other plants. Those plants can preserve the fertility of the soil and improve the environmental condition of the region. We do not concern the prospect of raising livestock in the GDome at the moments since many critics have pointed out that pastoralism has led to the severe decline in world’s food supply since resources and plants’ products are diverted to livestock’s production. Nonetheless, grazing and livestock’s’ feces can also fertilize the soil. We may look more into this aspect in the future.

8. Conclusion: Our GDome may seem to be expensive and requires a paradigm shift in the mindset of consumers, producers and governments to be adopted and used widely. But with arable land being degraded and climate change hastening the process, many scientists are calling for more sustainable models of agriculture. We believe that our GDome is an answer to their hopes and wishes.

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