Hydroponics Basics and Principles

Environmental Studies & Life Sciences

• This presentation covers various topics related to environmental studies and life sciences.
• Specific subtopics are discussed including bio-sustainability, organic farming, vermicomposting, hydroponics, rain water harvesting, biofuels, and bioremediation.
• The slides incorporate diagrams and images to illustrate the concepts discussed.

Bio-sustainability - Organic Farming

• Organic farming is a method of crop and livestock production that specifically does not use pesticides, fertilizers, genetically modified organisms (GMOs), antibiotics, and growth hormones.
• It aims to optimize the productivity and health of diverse agricultural ecosystem communities, including soil organisms, plants, and livestock.
• A crucial goal of organic farming is to maintain long-term soil fertility.
• The International Federation of Organic Agriculture Movements (IFOAM) defines organic agriculture as a system of production that sustains the health of the soil, ecosystems, and people reliant on ecological processes and biodiversity.
• General principles of organic production include environmental protection, optimization of biological productivity, recycling of materials, and using locally organized, renewable resources.
• Key methods for organic farming include crop rotation, green manures, compost, biological pest control, and the use of nitrogen fixing organisms and natural insect predators.
• The science of agroecology helps understand the benefits of polyculture.
• Polyculture (multiple crops in the same space) is often employed in organic farming.
• Planting a variety of vegetable crops promotes biodiversity and overall farm health.
• Organic farming promotes biological processes through microorganisms such as mycorrhiza and earthworms to enhance production of soil nutrients, and thus supporting healthy soil throughout the growing season.
• Organic farmers often use tools to minimize reliance on fossil fuels.
• India (in 2016) achieved the goal of 100% organic farming in Sikkim.
• Kerala, Mizoram, Goa, Rajasthan, and Meghalaya have also aimed to shift to fully organic cultivation.
• Andhra Pradesh promotes organic farming.
• India has the largest number of organic farmers globally (as of 2018).
• The number of organic farmers globally is significant, representing more than 30% organically certified producers.
• India (in 2018) reported 835,000 certified organic producers.
• Advantages of organic farming include lower production costs due to the avoidance of costly chemical fertilizers and pesticides.
• Organic farms often result in cleaner/healthier food and also save/protect long-term energy, help slow down global warming, protect biodiversity and reduce groundwater pollution.
• Organic farming creates new and beneficial living areas for livestock and other small animals and also maintains soil health through beneficial methods like crop rotation.
• The government of India launched two programs to boost natural/organic farming practices in 2015.
• The schemes include the Mission Organic Value Chain Development for the North East Region (MOVCD) and the Paramparagat Krishi Vikas Yojana (PKVY).
• These programs enhance farmer's ability to adopt organic farming and improve farming revenue due to premium prices.

Bio-sustainability - Vermicomposting

• Vermicomposting is a composting method enhanced by using certain earthworm species to convert organic waste into a superior end-product.
• It's a mesophilic biological process utilizing microorganisms and earthworms.
• Vermicomposting uses a mixture of decomposing vegetable waste or food waste, bedding materials, etc. to generate high quality organic fertilizer known as vermicompost.
• Red wigglers are commonly recommended as they are efficient and fast breeding species.
• Vermicompost is rich in nutrients and beneficial microorganisms needed to create healthy soil.
• Vermicomposting optimizes the process of treating organic waste and creating high quality compost quickly and efficiently.
• Vermicomposting is used in large scale.
• Vermicompost can be used as a soil conditioner by direct mixing in the soil.
• It can also be mixed into water to create worm tea (a liquid fertilizer).
• Vermiculture units are employed to process garden or kitchen waste in large-scale facilities.
• Vermicomposting offers many benefits regarding improved soil aeration, water holding capacity, and plant growth; enhanced germination, root growth, and crop yield.
• It also increases soil enrichment in microorganisms (with auxins and gibberellic acid).
• Bioremediation provides environmental benefits by facilitating waste conversion, reducing landfill waste, lowering greenhouse emissions like methane and nitric oxide.

Bio-sustainability - Hydroponics

• This is a growing method that does not need soil to cultivate plants.
• It is a Greek term that combines "hydro" (meaning water) and "ponos" (meaning labor).
• The concept of soil-less growing has existed for thousands of years.
• Examples of early hydroponic systems include the Hanging Gardens of Babylon and The Floating Gardens of China.
• Scientific experimentation started around 1950 to develop soil-less gardening, and the method is much more efficient than traditional soil gardening.
• The rate of growth is significantly higher - approximately 30-50 percent faster - when using hydroponics in comparison to conventional soil gardening methods.
• Hydroponically grown plants often yield a greater yield/harvest.
• Benefits of hydroponic gardening include the potential to stimulate root growth due to the high oxygen content in the hydroponic growing medium.
• The nutrients are directly delivered to the root system thus eliminating the need to find nutrients in the soil.
• This also leads to using less energy and water resources.
• The frequent delivery of the nutrient mixture to the plant, and the reduced need to search for nutrients from within the soil, allows plants to produce more quickly.
• Hydroponic systems are either active or passive.
• Active systems employ a pump to move the solution to the plants.
• Passive systems involve capillary action in the growing medium to pass the nutrient solution to the plant roots.
• Hydroponic systems can be categorized as non-recovery (not reusing the nutrient solution) or recovery (reusing the enriched nutrient solution).
• The wick system (passive), the ebb and flow system, and continuous drip systems (all active) are common examples of hydroponic systems.
• Various growing mediums commonly used in hydroponics include Rockwool (a relatively popular medium), perlite, vermiculite, and various grades of sand.
• Hydroponic systems can also be fertilized like soil-grown plants, using organic or chemical substances.
• The use of nutrient solutions ensures there is sufficient amounts of elements that the plants would normally obtain from soil to aid successful growth and maintaining a stable pH throughout the plant's growth cycle.

Bio-sustainability - Rain Water Harvesting

• Rainwater harvesting is the collection and storage of rainwater, primarily to prevent it running off.
• The method of rainwater collection can be in tanks, cisterns, deep pits, wells, boreholes or reservoirs that can enhance percolation.
• This is a significant method of water self-supply that often is used across households and residential buildings.
• Larger projects to provide water for schools, hospitals and other facilities rely on funding from companies, organizations and governmental units.
• Rainwater harvesting in urban water systems reduces the need for clean water, reduces generated storm-water runoff into sewer systems and reduces runoff pollution, preventing contamination of freshwater bodies.
• The state of Tamil Nadu, India, initiated the compulsory use of rainwater harvesting for all new buildings to avoid groundwater depletion.
• In Bangalore, Karnataka, rainwater harvesting is mandatory for newly constructed buildings with a minimum site area.
• The Bangalore Water Supply and Sewerage Board has implemented a Rainwater Harvesting Theme Park (named after Sir M. Visvesvaraya) on 1.2 acres of land in Jayanagar.

Bio-sustainability - Biofuels

• Biofuels are renewable energy sources derived from organic matter or waste.
• They contribute by reducing carbon dioxide emissions.
• The use of biofuels is significant in transportation, often blended with existing fuels like gasoline or biodiesel.
• Biofuels have been promoted globally to mitigate dependence on fossil fuels to reduce greenhouse gas emissions and thus reduce climate change.
• Rapid increases of energy consumption and human dependence on fossil fuels have consequently led to the accumulation of greenhouse gases.
• Several types of biofuels have been developed.
• First-generation biofuels are derived from crops such as sugarcane, corn, wheat, barley, and canola, thus impacting the food source.
• Concerns arising from this method include potential negative impacts on competing food resources, considerable consumption of fossil resources, and huge land requirements needed for cultivation.
• The concept of second-generation biofuels is based on using lignocellulosic materials from various types of biomass as a rapid renewal carbon cycling (e.g. agricultural residues and woodchips) to convert into alcohol to generate bioenergy.
• The third generation biofuel, or algae fuel, or oilage method utilizes the algae to produce the different types of biofuels (e.g., biodiesel, gasoline, and different types of alcohols) with high yields. This method is considered a significant step towards producing a high yield of biofuel.
• The fourth generation biofuels approach involves combining genetically engineered and genomically prepared microorganisms (cyanobacteria) to enhance their oil yield and efficiently produce bioenergy.
• Biofuels like biogas, syngas, bioethanol, biodiesel, green diesel and bio-ethers are common biofuels currently developed and used globally.
• Bio-diesel produced from Jatropha curcas seeds can be used as a substitute for petroleum-based diesel fuel.
• Bioenergy comprises of harvesting biomass and using various processes to produce fuel from this.
  • One common process for making biofuels from biomass or cellulose is to use microorganisms, such as bacteria and yeast to produce ethanol from the sugars.

Bio-sustainability - Bioremediation

• Bioremediation is a process where microorganisms are used to remove/neutralize pollutants in the environment without the use of harsh or harmful chemical products.
• It utilizes living organisms to reduce, detoxify, degrade, mineralize or transform more toxic or harmful pollutants to less harmful or harmless substance.
• The method has various types/techniques that can be categorized into ex situ and in situ.
• Ex situ methods involve removal of contaminated substances from one place to another for treatment, e.g., soil treated in bioreactors, land farming or composting methods.
• In situ methods involve treatment in place, for example, methods like biosparging, bioventing, composting, land-farming etc.
• Bioremediation techniques can involve:
  • Bioaugmentation: Addition of bacterial cultures to contaminated mediums to expedite the breakdown of pollutants into less harmful or non-toxic substances.
  • Biostimulation: Stimulation of populations of microbial species through nutrient addition to existing microbes.
  • Bioreactors: Biodegradation within a container or reactor to effectively treat several liquid wastes or slurry substances.
• Bioremediation can be used in various instances such as oil spill clean-up, cleanup of blood/bodily fluids, and contaminated soil cleanup.
  • Various examples of oil spills have been effectively remediated via bioremediation.
• There are species of marine bacteria that can directly consume petroleum compounds.
  • Research regarding genetically modified microorganisms has resulted in patents for bacteria that are designed to "eat up" oil spills and other toxins or contaminants.
• Phytoremediation involves the use of plants to remove, degrade, stabilize and destroy pollutants in the soil/groundwater.
  • Phytoremediation uses various plant technologies such as:
    • Phytoextraction
    • Phytostabilization
    • Phytodegradation
    • Phytovolatilization
    • Rhizofiltration
  • Each mechanism works to manage the different types of pollutants.
• The method is beneficial as it results in reduced or no harmful byproducts to the environment.
• Advantages and Disadvantages are related to the process.

Bio-sustainability - IoT/Smart Farming

• This presents the use of the Internet of Things (IoT) in smart farming practices.
• Farmers can use various devices/sensors to collect data from the field and implement advanced agricultural practices. The methods can be implemented on mobile phones/simple processes.
• Real-time monitoring of environmental factors using sensors like humidity, temperature, etc allows for optimized control of growing processes, including better decisions related to production management and thus maximizing efficiency.
• This collection and analysis can predict failures in machinery, enabling proactive maintenance and avoiding costly equipment downtime.
• Technologies like drones and robotics can optimize agricultural processes through automation of tasks such as planting seeds, watering plants, harvesting, spraying pesticides, milking cattle, picking fruits, and irrigating, processes that can be done more efficiently/with less labor effort.
• Increased use of solar-powered refrigerators helps in the preservation of fresh produce during harvest, storage, and distribution.
• The technology can potentially reduce pesticide use, water use, energy use, enhance efficiency of processes, increase profitability and provide a more precise approach toward agricultural practices.
• It's important to note that there are also limitations related to the risks of potential damages due to weather and maintenance costs associated with this type of technology that further impact the success of the process.