Where Did All the Water Go? A Detailed Look into the Global Water Crisis
Introduction
Access to clean, running water is a basic need for all life living upon this earth. However, for too many inhabitants of this planet, access to clean water has become a luxury as water scarcity crises are rapidly increasing throughout the world. Water scarcity is a plight that plagues people living in developing countries as well as communities all across developed countries such as the United States and Canada. Often times the communities that are hit hardest by the water crises at hand are Indigenous First Nations and other marginalized communities throughout the globe. The global water crisis will continue to grow in severity until the current systems for water management and treatment are radically improved upon. This essay will detail several methods that can be implemented in order to help improve the water systems that are currently in place.
There are many contributing factors that have played a role in creating the global water crisis. Some of these factors include contamination to bodies of water by oil pipelines, climate change causing droughts, and inefficient use of water paired with overconsumption. Many hold the misconception that water is an infinite resource, but as the human population grows and pollution levels rise, the supply of usable water could become finite.
Agriculture takes up the majority of water consumption, often times for industrial farms that use the practice of monocropping. Monocropping is the practice of planting a single type of cash crop across a large portion of land. This practice simultaneously increases the amount of water needed to irrigate the crops, as well as completely destroys the quality of the soil. These crops all uptake the same kind of nutrients, without putting any nutrients back into the soil which in turn decreases the soil’s ability to hold onto water (Helmreich and Horn). This suggests that one major way to conserve water is to move to more sustainable methods of food production.
A simple, yet very effective method that can be implemented into agricultural practices is adopting a permaculture system. Permaculture is the practice of planting many different crops in a single growing space. An ancient example of permaculture is the Indigenous practice of planting what’s known as the “three sister crops,” which are corn, beans, and squash. The corn grows tall and provides shade for the beans and squash, as well as providing a trellis for the beans to grow on. The shade provided by the corn allows for water to be conserved due to less water being lost from evaporation from heat and sun exposure. The plants also don’t lose as much water from transpiration, which is when water vapor is exhaled through the stomata of the leaves for the same reasons as previously stated. In addition to conserving water, this method of growing allows for more crops to be grown in a smaller amount of space as well as improving the quality of the soil by the nutrients that are used and put back into the soil by these plants. This would increase the amount of water that the soil is able to retain.
In addition to revolutionizing the way in which agriculture is practiced, another method that could provide a reliable source of clean water is the act of harvesting water from rain and snow. Rainwater harvesting could be implemented on both the industrial as well as domestic scale. Even in places like the desert or places that are experiencing major droughts, this method would be useful. In these dessert-like areas, all that would be necessary to do would be to increase the capacity of storage space for the water that’s collected from precipitation. Once the water is collected, it would need to be filtered and treated in order to remove any contaminants that may be found in the precipitation. Rainwater treatment methods will be discussed further in a different section of this paper.
Lastly, another crucial way in which water can be conserved is through the practice of water recycling. Water recycling is not a new concept, as it is already taking place in a single form. Currently, sewage water is transported to sewage plants and treated in such a way that makes it usable again. While this is a good start, it is also very costly in infrastructure costs (Xu et al.). There are many other ways to recycle water before it even gets these sewage plants.
An ideal example of a domestic water recycling system can be found within what’s known as an Earthship home. This type of home was created by the architect Michael Reynolds in the 1970s in the desert conditions of Taos, New Mexico. This innovative structure combines rainwater harvesting with water recycling for maximum efficiency. After the rainwater is harvested and treated, the first use of water is known as potable water, which encompasses uses such as drinking, bathing, hand washing and laundry. After this first use, the water is then referred to as greywater. These homes have a built in greenhouse for food production, which serves as a greywater treatment system. The plants use the potential contaminants as nutrients which simultaneously cleans the greywater. After the botanical cells have cleaned up the greywater, it is then used as water for toilet flushing. Once the toilet water has been flushed, it is then referred to as black water, and is transported to a traditional sceptic system (Ekvall, 2019). In some experimental instances, in addition to the traditional sceptic system an outdoor botanical cell is implemented. The blackwater is once again treated by botanicals, and the plants uptake nutrients while cleaning the water. In treating the blackwater using a botanical cell, a beautiful outdoor landscape is created even in the driest of deserts. A feat that previously was not possible due to harsh desert conditions. Within this system, not a single drop of water goes to waste, and efficiency is maximized in every way.
Rainwater Harvesting and Treatment
Sources of Contamination of Rainwater
Harvesting rainwater is definitely a promising way to increase the availability of potable water across the world. While this sounds overly simple, due to environmental pollution, chemical contaminants, as well as microbial pathogens it is crucial that treatment methods are implemented before this water can be used for human consumption. Contamination within Domestic Rain Water Harvesting (DRWH) tanks come from many different sources. First, precipitation that travels through polluted airways, such as places that have a lot of industrial or agricultural activity, can carry many toxic heavy metals such as lead (Pb) and cadmium (Cd). It is important to note that these areas to not have to necessarily be close in proximity to where the precipitation is deposited, as rain carrying clouds often traverse many miles before reaching the destination in which the rain falls.
Second, the location in which the rainwater is being caught can have an effect on contamination levels within the DRWH tanks. A third source of contamination is fecal matter from animals that can lead to harmful pathogens if consumed by people. The last source of contamination that will be discussed is the potentiality of the catchment system and the tank itself. If these things are made from the wrong materials, it is possible that harmful substances can be leached into the water (de Kwaadsteniet et al.). Based on these factors, choosing the right materials for the tank and catchment system, the placement of the catchment system, as well as treatment to remove chemical and microbial contamination is of extreme importance for making this a safe practice.
Often times, the way in which rainwater is caught is by the run off from roofs. This indicates that the quality of the roof directly affects the quality of the collected rainwater. Factors such as the material of the roof, the geometry, roughness, surface coating, age, and maintenance history of the roof are all contributions to the quality of the rainwater collected (de Kwaadsteniet et al.). It is important to keep all of these factors in mind when building new DRWH systems in order to get things correct from the very start. It is suggested that lead and aluminum based coatings should be avoided in constructing roofs designed for rainwater harvesting, as these harmful elements can be leached into the water supply. The material of the tank itself, if chosen improperly may also leach contamination into the water supply. It has been shown that tanks made from concrete tend to have a higher pH than tanks made from non-concrete materials such as plastic, fiberglass, metal, and non-ferrocement. Cement tanks that have been studied have been shown to have a pH of about 7.5–7.6, whereas tanks made from non-ferrocement has been shown to have a pH of around 5.90 and tanks made from steel had a pH of about 7.26. The higher pH found in the cement tanks has been attributed to the potential leaching of calcium carbonate from the tank walls (de Kwaadsteniet et al.). Picking the right materials for constructing the run off systems and the DRWH tanks will ensure that the sources of contamination is kept to a minimum, and efforts can be focused on treating the contaminates that are entirely out of an individual’s control.
Several other factors that affect the quality of collected rainwater include meteorological events such as the given season, the amount of rainfall, general weather conditions, and the concentration of pollutant deposition into the atmosphere. A study carried out in Brisbane, Australia concluded that roughly 21% of the lead that can be found within rainwater comes from atmospheric deposition of pollutants. It was also shown that a majority of atmospheric deposition is a result of traffic, by ways of exhaust fumes and discharges. The secondary source of atmospheric deposition comes from industrial production of aerosols de Kwaadsteniet et al.). Due to these uncontrollable sources of chemical contamination, methods of removing these contaminants must be enacted before the harvested rainwater can be used. Treatment systems will also have to address other uncontrollable factors such as microbial pathogens in order to create usable water from collected rainwater.
Treatment methods of Harvested Rainwater
There are many treatment methods that will be discussed throughout the rest of this section. These methods will be compared in the categories of how effective they are at removing contamination, the amount of energy that is used to run these systems, how accessible they are for developed and developing areas, and how costly the systems are. Three types of approaches will be examined, the first approach being that the rainwater is treated within the storage tank, the second being that the harvested rainwater is removed and treated separately from the tank and then treated, the third being a botanical green roof hydroponic system.
In both all three treatment approaches, implementing screens and filters are generally used as the first step in bettering the quality of the rainwater. This would remove a large portion of the debris that collects on the catchment area. This debris acts as a chemical contaminant, but also creates ideal conditions for the growth of harmful bacteria. Therefore, removing debris from the collected rainwater should be utilized no mater what approach is being taken in regards to treatment. Both a course leaf screen or fine filter are good options to implement in these systems, and can be placed anywhere between the rooftop in which rain is collected and the inlet to the DRWH storage tank. This prohibits these larger sources of contamination from entering into the collected water. It is crucial that the filters are able to hold up when being subjected to high intensity rainfall. These filters should also be easy to clean, long lasting, as well as cost effective (de Kwaadsteniet et al.).
Another method that can be implemented no matter which approach is utilized is the act of flushing the first few millimeters of rainfall. These first few millimeters often are carrying the highest concentration of contamination which is likely a result of this rainwater washing away particles that have contaminated the surface of the catchment system. First flush diverters are easy to install, operate automatically, and are cost effective for how much they improve the quality of the collected water. By implementing this method, almost all parameters for safe drinking water according to Australia’s regulations have been met by flushing the first 1–2mm of rainfall. The only parameters that did not meet the regulation requirement is that of lead and turbidity levels, which have been resolved by flushing the first 4–5mm of rainfall (de Kwaadsteniet et al.).
Approach 1: Treating Rainwater within the storage tank
Using granulated activated carbon filters may also be a really good option for the type of approach in which the water is treated within the storage tank. Granulated activated carbon has a very high amount of surface area that allows for the removal of both chemical and microbial contamination. A laboratory study concluded that this pre filtration membrane method was highly effective at removing dissolved organic solvents (DOCs). This method was developed by Areerachakul et al. (2009). After the formation of a biofilm layer on the granulated carbon was formed, DOC removal efficiency was 40, 35, and 15% for filter depths of 15, 10, and 5cm respectively (Areerachakul et al.). The use of microfiltration membranes with a pore size of 0.1 micron, within this type of approach was able to remove 10% of DOC alone. When used in conjunction with the activated carbon and the biofiltration pretreatment, the DOC levels were able to be reduced by 45–50%. This method was also able to remove all of the heterotrophic bacteria that contaminates collected rainwater. (Areerachakul et al.)
Another method within the approach of treating the water within the storage tank is by employing the use of antimicrobial silver ions. This system consists of a settling tank, a cistern, a stainless steel filter, a silver ionizing unit, and a refillable granulated activated carbon filter paired with Kinetic Degradation Fluxion (KDF) filtration media. These systems were installed and evaluated in rural Mexico and it was concluded that these systems reduced total coliform levels anywhere between 62.5 and 99.9%. This system paired with a first flushing mechanism was able to reduce the chemical oxygen demand (COD) by 77%, and this paired with the filtering treatment system further reduced COD levels by 41% (de Kwaadsteniet et al.).
Approach 2: Treating Rainwater separately from the Tank
The second approach by way of removing water from the tank and then treated has many methods within this approach. Some of these methods include boiling the water, chlorination, slow sand filtration, and the use of solar technology in order to perform pasteurization.
Slow Sand filtration is a low cost, yet effective method in which rainwater is treated and is especially useful in the developing world. This treatment method is also referred to as biosand filters (BSF). In this method, there are several layers of differently sized granulated sand with the coarsest layer at the bottom with the finest layer on the top. A thin biofilm layer on the surface of the filter is what allows for the maximum efficiency of the filter. Therefore, this method acts as both a biological as well as a physical filter (de Kwaadsteniet et al.). This method is highly effective at removing bacteria and protozoa, 81–100% and 99.98–100% respectively. (Peters-Varbanets et al.). While it is highly effective at removing these types of contaminants, it is hardly effective in removing viruses. Therefore, this method would have to be used in conjunction with another type of method that uses the approach of treating the rainwater separately from the storage tank. This method may also be enhanced by coating the top layer of sand to remove even more bacteria as well as heavy metals. A dual filter contain manganese oxide and iron hydroxide is used for the coating of the sand. The sand coated with manganese oxide had been shown to be effective at removing heavy metals from the water, while the iron hydroxide coated sand was effective at removing microorganism and turbidity. This dual-coating method was found to remove 99% of bacteria and 96% of zinc found within rainwater collected from rooftops. It was also found that no leaching was observed in using this method (de Kwaadsteniet et al.). This method is also highly cost effective, as sand is often very inexpensive. This paired with the accessibility of sand is what makes this method so attainable, especially in developing communities.
Another method within the separation approach that is arguably even more accessible is that of utilizing solar irradiation, which is commonly known as solar disinfection (SODIS) and is not at all a new concept. There have been numerous studies that demonstrate the effectiveness of this method in treating microbial contamination within water. This method is simple and even less expensive than BSF. A study conducted in India of a SODIS system in which rainwater that was harvested from roof tops was exposed to the sun with a solar intensity of more than 500 W/m2 for 6 hours effectively inactivated all the coliforms present, however it was not very effective at treating heterotrophic bacteria as they were still present within the rainwater. A slightly higher-tech version of this technique is known as solar collector disinfection (SOCO-DIS) systems in which the collector has a rectangular base and open wings that are reflective. Disinfection using this collection system was shown to be 20–30% more effective comparatively to SODIS systems, even under moderate weather conditions. This is a result of the sunlight radiation, thermal properties, and optical inactivation that is allowed for by this type of collection method. SOCO-DIS systems were able to completely disinfect rainwater as well as obtain low turbidity even under strong weather conditions. This method increases in effectiveness when the pH of the rainwater can be lowered to about 5. In a laboratory setting, the pH is buffered down through the use of HCl. HCl is rarely accessibly to the average consumer, therefore for individual use rainwater can be buffered down using vinegar and lemon juice. Both acidic solutions resulted in an increase of effectiveness of both SOCO-DIS and SODIS systems by 40%, however using vinegar as the catalyst was able to eradicate heterotrophic bacteria more effectively than the lemon juice (de Kwaadsteniet et al.). It should also be noted that regrowth of microorganisms was significantly lowered within SOCO-DIS systems when comparted to SODIS systems (Amin and Han). A drawback to a SOCO-DIS system is that it is higher in cost and not as accessible to more rural, developing areas. Therefore, it would be recommended for a lower cost alternative to utilize BSF alongside SODIS systems for the lowest cost, and more effective treatment.
Approach 3: Hydroponic Green Roof Systems
The third approach of rainwater harvesting also combines the recycling of greywater. This method is that of using hydroponic green roof systems (HGRS). Hydroponics is the practice of growing plants using only water without any soil mediums. This method when compared to traditional green roof systems would be able to reduce the bulk density while simultaneously improving the storage capacity for rainwater as well as greywater. This is a result of the lack of soil, which traditionally takes up the most amount of space in this kind of system, while also being the heaviest substance within the traditional green roof system. Given that this system implements onsite recycling of greywater, strain placed of sewage treatment plants can be reduced which in turn lowers infrastructure costs. Currently, this method is only being considered for use in urban areas within the current infrastructure in place (Xu et al).
Traditional green roof systems rarely ever include the recycling of greywater in their designs, which causes plants to have to be irrigated with tap water when there is a lack of rainfall. This drives up the maintenance costs of traditional green roof systems, that do not occur within the hydroponic counterpart. The cost of this type of set up was calculated to be roughly 540$/m2 (Xu et al.). This is a very costly type system which is why it is currently only being implemented within urban and commercial settings.
When the HGRS was observed over the course of 8 days, DOC levels as well as turbidity, and anionic surfactant levels were greatly reduced. The removal rates of COD, anionic surfactants and turbidity were on average, 81%, 88%, and 75% respectively. Initially, the bacteria that was found within these systems was mainly that of anaerobic bacteria, while as time passed the bacteria that was mainly present became aerobic bacteria. As time passed, the system became even more efficient at removing COD and turbidity reaching 84% and 86% respectively (Xu et al.).
HGRS are effective at treating collected rainwater as well as greywater, as well as providing many other benefits such as lower operating costs, smaller volume density, as well as providing pleasing landscaping effects as well as ecological benefits. Due to these advantages, this method is expected to be widely applied within green buildings. Further investigation needs to be carried out in areas such as microbial hazards, optimal plant selection, changes in plant physiology and ecology, as well as the degradation of pollutants within the system (Xu et al.).
Greywater Treatment and Irrigation
In this section, the use of plants in order to treat and use grey water will be examined in three areas. These areas will include, the way in which using both raw and pretreated greywater affects the plant growth and physiology, the way in which both raw and pretreated greywater affects soil, and the effectiveness of using plants as a greywater treatment.
Example of potential bio-filtration cell
Effects of Greywater on Plant Growth and Physiology
Firstly, a study was conducted in which three different crops: lettuce, carrots, and peppers were all irrigated using three different water sources: tap water, raw greywater, and pretreated water for a total of 9 experiments. In this study it was found that the untreated and treated greywater samples did not produce a significant difference for all measured parameters. These parameters were crop yield by dry weight, crop height prior to harvest, as well as the quality of the appearance of the crop. The researchers concluded from their results that the treatment method was not effective (Gorgich et al.).
However, the conclusion reached at this point in the results fails to consider is the possibility that the differing effects between pretreated greywater, and raw greywater affected the quality of the soil rather than the quality of the plant itself.
Effects of Greywater on Soil Quality
A different team of researchers wanted to study the differing effects that pretreated and raw greywater had on the quality of the soil. This team of researchers concluded that raw greywater caused a major decline in the quality of the soil, which indicates that pretreatment of greywater before the use of irrigation when grown in soil is very much necessary. The negative effects that raw greywater had on soil was an increased level of surfactants, oils, gasses, coliform bacteria as well as an increased level of water repellency when compared to pretreated greywater or tapwater (Travis et al.).
Comparing Studies from different Research Teams on Both Plant Growth and Soil Quality
While the Gorgich et al. research team concluded that there was no significant difference in the crop yield, several other research teams (Xu et al., Travis et al., Laafat et al.) all had observed a significant increase in yield, growth rate, and appearance when crops were irrigated with both pretreated and raw greywater. Utilizing raw greywater still has negative affects on the soil, but overall has positive effects on the plants. It was concluded that the contamination within the greywater was actually provided useful nutrients to the plants that allowed them to grow at a more rapid rate as well as increasing crop yields. Given that raw greywater has negative effects on soil, but over all positive effects on plant growth as a whole, further studies in growing plants hydroponically in greywater should be explored further as done by the Xu et al. research group.
It was also concluded by the Gorgich et al. research team that different crops do better with this irrigation method than others. Leafy greens were found to have some coliform bacteria within the vegetation and it was more negatively affected by the greywater. It was inconclusive as to the effects that the greywater had on bulbous and root crops such as onions and carrots, which indicates further studies need to be done regarding those types of crops. The peppers faired the best out of all of the studied crops. This is likely due to several factors, such as the different nutrient requirements of each crop, as well as how long the plant life from seed to harvest takes. Peppers take the longest amount of time which means they have the most amount of time to build up a level of immunity to the harsher contaminants of grey water, as well as the edible part of the plant does not come into direct contact with the soil and the water. This provides the pepper plant with a sizeable buffer that allowed for them to fair better when irrigated with grey water.
It is also important to note that all greywater is not created equal, and that different products used by the people producing the greywater can have a significant effect on the outcome of the plants that are grown using greywater irrigation. This is likely what accounts for the varying results between the research groups regarding the growth rate and crop yields. The different products and therefore substances that are found within the different greywater provides different levels of nutrients to the plants. This suggests that further studies need to be conducted regarding which products are beneficial to the greywater system for maximizing plant growth and crop yield as well as which products have the most harmful effects towards the plants.
The Effectiveness of Plants as a Greywater Treatment
The average biochemical oxygen demand (BOD), COD and total suspended solids (TSS) of raw and pretreated greywater were measured after the water had been treated via botanicals. In pretreated greywater, BOD, COD, and TSS conctrations were fount to be 709mg/L, 1868 mg/L and 559mg/L respectively. COD values varied greatly for raw greywater from site to site from 92 to 2263 mg/L. This was due to the changes in quantity and type of products that are used by the people creating the greywater. Soil properties, for plants grown in soil, are of great importance. These qualities include the salinity (sodium absorption ratio, SAR) and organic content for use of nutrients are important factors for plants to grow well and healthily. On average, the SAR value of treated greywater was 3.62 times lower than the proposed methods that are in place that describe a suitable framework for irrigation. It should be noted that long-term reuse of grey water may have dramatic effects on soil over time in terms of the salt and metal accumulation. Once these things acculate in the soil, it may cause the plants to start up taking these contaminants, thus having a negative effect on the plants (Gorgich et al.). This further supports the need for exploration in hydroponic use of greywater in order to avoid the problems that may accumulate in the soil.
Further Studies
It was already clearly observed that in a limited scope, different plants do better under the conditions of being irrigated with greywater. It should also be of no surprise that different plants are more effective in cleaning up the greywater. This is an area that should be further studied in order to determine which plants are the most efficient in treating the greywater as well as which plants grow better under these conditions. Studies should also be conducted regarding the ways in which greywater needs to be treated in order to optimize the water for hydroponic use. The greywater alone lacks crucial nutrients that plants need, and therefore if the plants were to be irrigated hydroponically, these nutrients would need to be added to the grey water. Given that plants are also in direct contact with contaminants that may be found in greywater, and they do not have the added protection of a soil buffer, the effects on these plants should be studied in order to verify that this would be a suitable method for growing crops.
Addressing The Industry of Agriculture
Damages Caused by the Industry
The agricultural industry is both the culprit for using the most amount of water, as well as the single most polluting industry there is by use of herbicides and pesticides. Many sources have stated that roughly 70% of the world’s water consumption is used for agriculture, and about 60% of water pollution comes from harmful chemicals used in the industry. If the way in which water is consumed is to be changed, the agricultural industry must also radically change. There are many ways in which agriculture production can be increased, the use of extremely harmful pesticides and herbicides can be eradicated, while simultaneously conserving up to 98% of water when compared to the current ways of doing things. The most effective way to revolutionize the agricultural industry is to start widespread implementation of the practices of hydroponics and aeroponics.
An Explanation of Hydro and Aeroponics
Derived from the Greek roots, hydro meaning water and ponos meaning labor, hydroponics is the act of growing plants without soil. This is done by enriching water with all the nutrients a plant needs and delivering water to the plants in different ways. There are many different types of hydroponic systems, the most effective of which is that of aeroponics. Aeroponic growing is an extension of hydroponics, with the root aero meaning air. In this system, the nutrient rich solution is atomized ultrasonically that delivers a fine mist to the roots of the plants. Both of these systems conserve upwards of 98% of water (NASA).
The Benefits of Aeroponic Growing
Aeroponics is a wildly successful method of agriculture for a number of reasons. For one, the particle size of the created mist is roughly 5–10 microns. This range falls perfectly within the pore size of most roots, which is about 7–10 microns. (NASA) Therefore roots can directly intake the water and nutrients that they need in order to grow as well as intaking more nutrients. This allows for plants to grow at a much faster rate, which is about three times faster compared to traditional farming. This dramatically increases the crop yield, which would be able to make feeding the growing population a much easier task. Also, given that through this method, plants are taking in an increased amount of nutrients, this suggests that the food produced through this method may even be more nutritional than the food being produced at farms that do not use this method. As mentioned in the introduction to this paper, the practice of monocropping depletes the levels of nutrients within the soil. The food that is grown in nutrient deficient soil is subsequently lacking nutrients as well. This is another serious disadvantage for the farming practices that are currently the industry standard.
Both hydroponic and aeroponic systems eliminate the need for harmful pesticides and herbicides because they are grown in a completely controlled environment, and are not exposed to pests and weeds that can come from growing within soil. Given that the environment is completely controlled, this also allows for crops to be grown all year round, which in turn increases the amount of food that can be grown from a single farm. Another major advantage to growing crops this way is that vertical space can be utilized to dramatically increase the amount of crops that can be grown, as well as utilizing the space that is created by the absence of soil. The act of growing plants solely in water also causes plants to have a lower potentiality of being introduced to diseases that have regularly been responsible for wiping out entire farms worth of crops throughout history. This is due to the fact that waterborne diseases have a much harder time surviving without the presence of soil that would provide these diseases with a suitable host (Xu et al.). The only way in which diseases could be introduced to the plants is if the plants were to be given contaminated water in the first place. This would be an illogical thing to do, and only water that has been pre-treated to the same standards that are applied to potable water should be used in these systems.
How Aeroponic Growing can Revolutionize the Industry of Agriculture
If aeroponic growing became the agricultural industry standard, and 98% less water would be consumed by this industry, water consumption would fall form 70% to 1.4%. This would have the potential to completely erase all water scarcity throughout the world. It would also decrease pollution levels by 60%. This would make treating water for potable use a much easier task, as there would be far less contaminating factors within the waters collected. The increased amount of space for growing crops paired with rapid growth of such crops astronomically increases crop yields while also lowering the cost it takes to grow these crops. This would allow for the cost of fresh food to be much lower, making fresh, nutrient food accessible for everyone. This would effectively eliminate food insecurity while having major health benefits for consumers.
Conclusion
The world as we know is approaching its tipping point, as the climate continues to rapidly change. If things continue to progress in this manner, there will come a point of no return. That being said, it is not too late to reverse a lot of the damage that has been done, but the point of no return is quickly approaching. Implementing the practices laid out in this paper would be a massive step in the right direction towards healing the wounds of the earth that have been left by humanity. While these practices are immensely helpful, they are only a starting point to the change that needs to occur within the human way of life. Changing the way in which we consume our water will also likely bring change to other intersecting systems such as agriculture and other industries. Every system, industry, country, community and induvial needs to start implementing sustainable practices into their way of life if life on earth is to continue. Everything is interconnected, with water being the most important resource on this planet, for every living lifeform. As mentioned in an earlier section, areas that are highly polluted can cause polluted rainwater to be deposited to far off places, this further reinforces the fact that the damage done in one area does not solely affect that single area. This damage has ripple effects throughout the entire world. However, this goes both ways and positive change is also capable of having this kind of ripple effect.
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