“SODIUM POLYACRYLATE IN DIAPER GEL AS STAND-IN ORGANIC FERTILIZER”

Antipolo Immaculate Conception School

“SODIUM POLYACRYLATE IN DIAPER GEL AS STAND-IN ORGANIC FERTILIZER”

An Investigatory Project Proposal Presented to Mr. Rene s. Ferrer

In Partial Fulfilment Of the Requirements for the Fourth Grading Period in Science X Academic Year 2015-2016

STEPHEN JUSTINE S. DELIMA CRISTINA M. LEGASPINA CLAIRE F. PEREZ JAMES EDWARD E. ZERRUDO 2016

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ACKNOWLEDEGEMENT The researchers were indebted to and would like to extend their warmest and heart-felt gratitude and appreciation to the following individuals who helped them in making this study successful: Classmates, for sharing their expertise, invaluable support, and generosity in helping the researchers pursue this investigative paper. Mr. Rene Ferrer, for his guidance, encouragement, and for unselfishly sharing her professional expertise, patience and dedication in giving inputs in turning this paper into a worthwhile one and to pursue this study. Family & Friends, for their generous guide to the researchers in creating a very significant study and patience in the culmination of genuine values and discipline in making this paper. Among all, to the Almighty Heavenly God, for providing the researchers the knowledge, strength, wisdom and clarity which made this study successful.

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DEDICATION To our loving parents, for their patience when we became “impossible” as we write this paper, and inspiring us when things seem to reach the point of being “impossible”. Above all, to the Almighty God, for giving us Strength of Mind, Courage and Perseverance.

To you we give all what we are, and what we will be!

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TABLE OF CONTENTS

Fly leaf.............................................................................................................................1 Acknowldegement..........................................................................................................2 Dedication.......................................................................................................................3 Table of Contents...........................................................................................................4 Abstract...........................................................................................................................5 Chapter I Introduction..........................................................................................................6 Background of the study.....................................................................................9 Conceptual Framework of the Study...............................................................10 Research Paradigm...........................................................................................11 Significance of the Study..................................................................................13 Hypotheses of the Study...................................................................................14 Chapter II Conceptual Literature........................................................................................15 Related Study.....................................................................................................18 Chapter III Methodology.......................................................................................................23 Chapter IV Documentation...................................................................................................29 Chapter V Conclusion and Recommendation...................................................................36 Chapter VI Bibliography.......................................................................................................38

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ABSTRACT The increasing impacts on the environment due to agricultural practices in the country have gradually affected the quality of the soil in terms of structure and biological equilibrium, which has required the development of alternative practices to minimize and mitigate those impacts, parallel to the improvement on the yield per cultivated area and economical benefits for producers and farmers. In addition, the amount of food that society of today require for processing and supply of the industry has encouraged the creation of new options for agricultural practices, tending to be: i) less invasive to the environment ii) cheaper than conventional techniques iii) able to increase efficiency at low costs iv) able to obtain better characteristics on harvests and v) ease of use and implementation with no excessive technical requirements. As a result, technologies such as bio fertilization have emerged in order to minimize environmental impacts and take advantage of the resources available in the field. The main scope of this paper is to assess researches performed with the use of bio fertilization, mentioning their advantages and limitations, reviewing some results on efficiency and benefits acquired in recent years and highlighting their potential for better agricultural practices community-wide.

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CHAPTER I THE PROBLEM AND ITS BACKGROUND

Introduction The growing need for supply of agronomic products for food and consumer goods processing by the modern society has caused substantial increases in agrarian activities in recent decades. As a result, the need for implementation of methods that allow, among other things, to improve the efficiency of crops, mitigate adverse impacts on the soil, reduce the use of chemical fertilizers, and increase revenues per cultivated area, have been addressed. For this reason, the implementation of conservative agriculture (CA) models has been a cornerstone of farming practices globally (Benitez et al 2002; Morte et al 2003). The CA focuses on reducing adverse impacts on the environment, increasing crop yields and inputs, and implementing sustainable techniques for development of agriculture. Biological fertilization is based on the use of natural inputs including fertilizers, decaying remains of organic matter, crops excess, domestic sewage, animal manure, and microorganisms such as fungi and bacteria (Chirinos et al 2006). They are used to improve fixation of nutrients in the rhizosphere, produce growth stimulants for plants, improve soil stability, provide biological control, biodegrade substances, recycle nutrients, promote mycorrhiza symbiosis, and develop bioremediation processes in soils

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contaminated with toxic, xenobiotic and recalcitrant substances (Morte et al 2003; Corpoica 2007; Rivera-Cruz et al 2008; Alvarez et al 2007). Additionally, the use of bio-fertilizers can improve productivity per area in a relatively short time, consume smaller amounts of energy, mitigate contamination of soil and water, increase soil fertility, and promote antagonism and biological control of phytopathogenic organisms (Chirinos et al 2006; Corpoica 2007; Porcuna et al 2002). The aforementioned aspects are translated into profitable benefits for farmers as a result of lower costs associated with the process of fertilization and higher crop yields (Fundases 2005; Gonzalez et al 2002). In this sense, biologic fertilizers application can bring benefits from an economic, social, and environmental point of view. However, the implementation of fertilization techniques requires feasibility studies, monitoring of environment variables involved in metabolic processes, acquisition of biological inputs, capital investment, time, and trained personnel (Plaster 2000; Vanegas 2003; Alegre 2000; Fresco 2003). In order to achieve a sustainable agriculture is necessary the implementation of plans, programs, projects and initiatives directed toward the minimization of environmental impacts and consequent benefits for farmers and producers. As a result of recent investigations performed to effectively assess the implementation of biological fertilizers under varying conditions, a review on their benefits and limitations is required to provide a valid background for academics, farmers and producers to perform future research complementing current work that deeply assess economical, environmental and social aspects related to the agricultural expansion worldwide. This paper focuses on the review of current research resulting 7

from the use of biological fertilizers in different regions of the world to obtain a framework that facilitates the development of future investigations in the agricultural sector and, consequently, promote the reduction of environmental impacts associated to the permanent use of chemical fertilization. Firstly in this article, an introduction to bio fertilization techniques is addressed to understand the fundamentals that explain their functioning. Next in the paper, benefits and limitations of bio fertilizers are mentioned followed by current researches’ results from the use of the techniques in various geographical backgrounds. Finally, conclusions and recommendations complete the paper.

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Background of the Study Many are of sure cognizance that fertilizers are used for proper and healthy growth of plants, but are they really healthy? What exactly are fertilizers? Well, a fertilizer is a substance, be it synthetic or organic, which is added to the soil in order to increase the supply of essential nutrients that boost the growth of plants and vegetation in that soil. With the rapid increase in population globally, the demand of food and agricultural yield has been rising tremendously. This is the reason why statistics show that almost 40-60% of agricultural crops mainly from lowlands and highly urbanized areas such as Metro Manila are grown with the use of different types of fertilizers. Not only this, more than 50% people feed on crops that are grown as a result of using synthetic fertilizers. On the other hand, there are organic fertilizers that consist of manures and animal wastes.

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Conceptual Framework of the Study

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Research Paradigm The study intends to get the level of satisfaction while using the diaper gel polymer as a substitute organic fertilizer purposive for crops and certain fruit-bearing plants standing mostly on household backyards. Specifically, it tries to seek answers the following sub-problems: 1. What are the components present in diaper gels being responsible for massive absorption of nutrients in soil? 2. What is the level of satisfaction of using the diaper gel as stand-in organic fertilizer in the following variables: 1.1 speedy growth 1.2 plant potency 1.3 yielded crops or fruit 1.4 congeniality to other soil types 1.5 affordability 1.6 hypo-allergenic 1.7 environment-friendly 1.8 economical

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3. What is the Antipolo City Sanitation and Health Services Officer’s level of satisfaction on the use of diaper gel polymer as a substitute organic fertilizer. 4. Is there a significant difference between the level of satisfaction of the consumers, as to City Sanitation and Health Services Office in utilizing stand-in polymer based organic fertilizer?

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Significance of the Study The use of organic fertilizer in sustainable gardens and farms will quickly gain its popularity which is evident in the number of increased acres of organic agriculture, chiefly in Cordillera Administrative Region and urban Manila as well, having 59 million in 2015 to nearly 81 million in 2016, especially as their mitigating effects on the environment are demonstrated through more and more studies. While the use of synthetics amendments is both dangerous and expensive and might as well be not considered sustainable.

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Hypotheses of the Study

NULL HYPOTHESIS There is no significant difference on the level of satisfaction of the consumers, as to Antipolo City Sanitation and Health Services Office in utilizing standin polymer based organic fertilizer.

ALTERNATIVE HYPOTHESIS There is a significant difference on the level of satisfaction of the consumers, as to Antipolo City Sanitation and Health Services Office in utilizing stand-in polymer based organic fertilizer.

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CHAPTER II REVIEW OF CONCEPTUAL LITERATURE AND RELATED STUDY

Conceptual Literature Mother nature has always taught us to balance out everything, and still continues to do so. If you eat a lot, your body naturally bloats up and tells you to exercise and come back to shape. When you exercise too much, your body tells you to slow down and relax. If there is rain, you also get the Sun, each and everything works fine till a balance is maintained. And we all know the consequences of imbalance. A classic example for the same would be the rise in global warming due to various reasons, including deforestation. Same is the case with fertilizers. The problem is that humans tend to use too much of fertilizers in the soil because they have to cater to the global demand of food. As mentioned already, more than half of the total yield production is out of synthetic or inorganic fertilizers which contains components like nitrogen, potassium, sulfur, calcium, magnesium, and so on. These chemicals and minerals, although help in boosting the growth of plants, they also have their drastic side effects in the long run.

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Mentioned below are some key points defining the effects of using fertilizers on the environment.

Depletes the Quality of the Soil Though this may sound ironic to you, the fact is that using too much of fertilizers in the soil can alter the fertility of the soil by increasing the acid levels in the soil. Which is why it is recommended to get a soil test done at least once in every 3 years so that you can keep a track whether or not you are using the right amount of fertilizers. The levels of soil pH varies from 0-14, wherein 0 is considered to be the most acidic and 14 being the most basic. 7 is considered to be neutral. The ideal soil pH varies from plant to plant and can be altered by bringing in some changes. Bottom line for using too much of fertilizers in the soil is that, though it may seem to work currently, there are high chances that you may not use it for plant yielding in the long run. Alters the Biology of Water Bodies When you use too much of fertilizers in the soil, it leads to eutrophication. Fertilizers contain substances like nitrates and phosphates that are flooded into lakes and oceans through rains and sewage. These substances prove to become toxic for the aquatic life, thereby, increasing the excessive growth of algae in the water bodies and decreasing the levels of oxygen. This leads to a toxic environment and leads to death of fish and other aquatic fauna and flora. Indirectly, it contributes to an imbalance in the food chain as the different kinds of fishes in the water bodies tend to be the main food

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source of various birds and animals in the environment. You would be surprised to know that more than 50% of the lakes in the United States are eutrophic!

Effects on Human Health The nitrogen and other chemicals present in the fertilizers can also affect the ground waters and waters that are used for the purpose of drinking. One of the most common result for this can be the development of blue baby syndrome which occurs in infants whose incapable enough of standing through sensitive air conditions.

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Related study With the advent of the so-called Green Revolution in the second half of the 20th century—when farmers began to use technological advances to boost yields—synthetic fertilizers, pesticides and herbicides became commonplace around the world not only on farms, but in backyard gardens and on front lawns as well. These chemicals, many of which were developed in the lab and are petroleumbased, have allowed farmers and gardeners of every stripe to exercise greater control over the plants they want to grow by enriching the immediate environment and warding off pests. But such benefits haven’t come without environmental costs—namely the wholesale pollution of most of our streams, rivers, ponds, lakes and even coastal areas, as these synthetic chemicals run-off into the nearby waterways. When the excess nutrients from all the fertilizer we use runs off into our waterways, they cause algae blooms sometimes big enough to make waterways impassable. When the algae die, they sink to the bottom and decompose in a process that removes oxygen from the water. Fish and other aquatic species can’t survive in these so-called “dead zones” and so they die or move on to greener underwater pastures.

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A related issue is the poisoning of aquatic life. According to the U.S. Centers for Disease Control (CDC), Americans alone churn through 75 million pounds of pesticides each year to keep the bugs off their peapods and petunias. When those chemicals get into waterways, fish ingest them and become diseased. Humans who eat diseased fish can themselves become ill, completing the circle wrought by pollution. A 2007 study of pollution in rivers around Portland, Oregon found that wild salmon there are swimming around with dozens of synthetic chemicals in their systems. Another recent study from Indiana found that a variety of corn genetically engineered to produce the insecticide Bt is having toxic effects on non-target aquatic insects, including caddis flies, a major food source for fish and frogs. The solution, of course, is to go organic, both at home and on the farm. According to the Organic Trade Association, organic farmers and gardeners use composted manure and other natural materials, as well as crop rotation, to help improve soil fertility, rather than synthetic fertilizers that can result in an overabundance of nutrients. As a result, these practices protect ground water supplies and avoid runoff of chemicals that can cause dead zones and poisoned aquatic life. There is now a large variety of organic fertilizer available commercially, as well as many ways to keep pests at bay without resorting to harsh synthetic chemicals. A wealth of information on growing greener can be found online: Check out OrganicGardeningGuru.com and the U.S. Department of Agriculture’s Alternative Farming System Information Center, for starters. Those interested in face-to-face advice should consult with a master gardener at a local nursery that specializes in organic gardening. 19

Chemical Fertilizer vs Organic Fertilizer Nitrogen fertilizers break down into nitrates upon application. Nitrates are necessary for the plants growth but an excess will leach into groundwater supplies and can contaminate sources miles away. Because nitrogen leaches through the soil more quickly, over-application is abundant. These chemical fertilizers have a hugely negative effect on plant and aquatic life, as well as human health. Numerous studies have shown the negative effects chemical fertilizers have on our environment and health. One study from Stanford University is a great example of the difference between the use of chemical and organic fertilizers. According to its findings, soil fertilized with organic fertilizer contained naturally occurring microbes that turned any excess nitrogen into a benign gas, dinitrogen. These microbes are found less frequently and were less active in soil fertilized with chemicals. The more leaching of nitrogen, the greater application is applied, the fewer microbes and the more poisoning of land and water. And when comparing chemical fertilizers vs organic fertilizers it's important to mention one study from the University of California, Berkeley that states sustainable farming can indeed "feed the world", despite what proponents and manufacturers of

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chemical fertilizers would have us believe. It produces as high harvest rates, using less inputs and virtually eliminates the pollution or contamination that leads to health and environmental issues.

Most Sustainable Organic Fertilizer There are many kinds of organic fertilizer and the options can be overwhelming. But as mentioned before, organic doesn't always mean sustainable. The best tip to keep in mind for home gardening is to avoid purchasing your amendments from the store. Purchasing a garden amendment still contributes to waste, instead of eliminating it. Alternatively, creating a closed-cycle within your home or community accomplishes two tasks at once.

Compost: You really can't get enough of this. Made from your own yard and kitchen scraps, compost creates a fully closed-cycled system within your home. Little is wasted and its benefits are unsurpassed as both a soil amendment and mulch. Compost in greater amounts can also be acquired from local farmers or for free from communities with a composting program. It contains a lower nitrogen level, so use it in conjunction with the techniques below. It can be applied as frequently and as thickly as you'd like or feel you need, but twice a year (spring and fall) and one inch thick is generally preferred. Read more about home composting here. 21

Grass clippings: They decompose quickly and provide the soil with nitrogen and other nutrients (between 2-5% depending on the season). They also diminish weeds and act as mulch, conserving water. They can be acquired for free from neighbor's lawns but avoid clippings from weedless lawns, as they likely contain herbicides that can damage your soil's microbial activity. Add approximately a two inch layer of grass clippings in the spring, when the nitrogen levels are at their highest and slightly more in the fall when levels are lower. For fertilizing lawns, simply remove the bag from your mower (or use a push mower) to leave the clippings on the ground.

Manures: High in nitrogen, animal waste from cows, horses, chickens, or pigs are a great amendment to the soil and give sustainable use to an otherwise smelly byproduct. Trust me when I say many animal owners will be more than happy to have you shovel out their pens or corrals, making manures readily available and practically free. Horse manures are used less frequently as they are more likely to contain seeds from alfalfa or hay, which may sprout and take over your yard. However, I've used them without issue and since alfalfa can act as a cover crop, it can be beneficial in small amounts.

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CHAPTER III METHODDOLOGY

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Procedure

DIAPER GEL 1. For this project you’ll need one of these disposable diapers. New or gently used, it doesn't really matter. 2. Now most people know that a diaper can hold quite a bit of liquid, but you might be surprised to see how much. 3. We tried putting over 4 cups of water in this thing, and you can see that in just a few seconds, all the fluid is completely absorbed, without a drop left in the bowl. 4. To see what's inside, let's go ahead and rip it open, and dump the contents into a bowl. 5. We can see that if we add a bit more water and mix it together, we've got ourselves an amazing, fiber rich hydrogel. 6. We tried packing some of this stuff into an airtight bag and freezing it overnight, to make an improvised ice pack that won't leak.

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HYDRO SOIL 1. Now, we used food coloring to change the color of the gels, but when working with plants it's best to leave it clear. This way, the plants won't turn funny colors as they grow. 2. One adult sized diaper makes over 12 cups of hydrogel, and the small pieces of cotton wadding break apart and mix right in. 3. Now we're going to need some all purpose potting soil that you can get at any home improvement store, and a large mixing bowl to dump it in. 4. Add equal parts of dirt and gel, then begin working the two together until they're thoroughly mixed. 5. Now we’ve got a super absorbent, super soil that's light and fluffy, and perfect for your potted plants.

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POTTED PLANTS 1. In the event of an extreme overwatering like this, you might expect that the plants would drown, or begin to rot. 2. But with the hydrogels infused in the soil, we can see how the excess water is quickly absorbed, keeping the soil damp and fluffy, and possibly saving the plants as a result. 3. Now the reason this mixture will hold so much liquid is because of these superabsorbent water crystals. 4. They'll hold over 500 times their weight in water, and if you want to separate them out, try ripping apart the wadding in the diaper, and shaking it upside down over a piece of paper. The cotton fluff should blow away, and you'll be left with just the crystals. 5. Go ahead and throw a little soil into the pot first, then help the plant get comfortable. 6. To hold it firm in place, just keep packing more soil until everything sits tight. 7. We can finish up by giving the plant a bit more water, and now with the super crystals in your soil, your plant can go twice as long between waterings, saving you time, and resources. 8. This diaper gel can work on your existing plants as well. As the gel expands and contracts, it will naturally aerate the soil as it does. 9. Just grab a knife and a spoon, and gently nestle them down between the roots, and spread them apart to form a gap.

10. Now we dropped some gel down to the roots, work the soil back together, and continue around the pot until all your water-gel is used up.

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SEED STARTERS 1. If you're looking for a lazy way to get your seeds started, just dump them into a batch of the grow dough, and give it all a good mix, or you could even just sprinkle the seeds on top. 2. Fill a container of your choice, add a bit of water, and find a place that you can set it and forget it. 3. Over the course of a week, the seeds will automatically sprout and begin to grow, without any extra effort, or any extra water. 4. For one final idea, you can help preserve your fresh cut flowers, by adding sugar, vinegar, and a bit of bleach to some warm water. 5. This will create a homemade flower food, and when you add your slush powder, you'll see it absorbs the solution and slowly grows up to 60 times its size. 6. By agitating the gel you can create an awesome effect that looks like crushed ice. 7. Not only does it look cool, but it's slowly releasing water as the flowers need it, and feeding them at the same time. The gel is completely non-toxic.

GARDENING It's biodegradable, and environmentally friendly, so it's a great option for working into your garden. Not only will this save you on watering costs, but it will also last quite a few seasons before it needs to be replaced.

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Well now you know how to take an ordinary diaper, and convert it into an extraordinary super soil, that will help keep your plants happy, and hopefully keep you happy as well.

CHAPTER IV DOCUMENTATION

DIAPER GEL

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HYDRO SOIL

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POTTED PLANTS

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SEED STARTERS

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GARDENING

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CHAPTER V CONCLUSION AND RECOMMENDATION

A. Biological fertilization techniques are pertinent strategies for an efficient and rational use of agricultural resources with minimal generation of adverse

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environmental impacts that may affect water resources, ecosystems or the quality of human life. In addition, biological fertilizers provide a wide range of possibilities for the development of conservative agriculture in different geographic, economic, and cultural backgrounds. B. Current researches clearly show that bio fertilization techniques require less chemical inputs on the soil and facilitate the incorporation of residues that would otherwise go to dumping sites and landfills, which represents relevant reductions on the environmental impacts associated to agriculture activities nationally. C. Limitations of biological fertilization require future research focused on identifying the options available to tackle the issues and offer valid frameworks for development of environmentally friendly practices around the world that allows improvements on the efficiency and consequent supply of product for the industry in the global economies. D. Although several options for application of bio fertilizers are available, feasibility studies should be carried out by producers and farmers to effectively select the best option that offers better results and allows minimizing environmental impacts. E. Bio solids, animal manures, green manures, composting, microbial inoculants and seaweeds extracts are techniques widely used in today’s agriculture, however, their implementation still requires research, investment, and technological development to fully understand their impacts on the soil, flora, fauna and, ultimately, on human health.

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CHAPTER VI BIBLIOGRAPHY

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Alfonso E, Leyva A y Hernández A 2005 Microorganismos benéficos como biofertilizantes eficientes para el cultivo de tomate (Lycopersicon esculentum,

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Mill).Revista Colombiana de Biotecnologia 2(2): 47-54. Available online at http://www.revistas.unal.edu.co/index.php/biotecnologia/article/view/498/891

Álvarez C, Scianca C, Barraco M y Klappenbach J 2007 Impacto de fertilizantes biológicos sobre la productividad del cultivo de girasol. Córdoba, Argentina: Instituto Nacional de Tecnología Agropecuaria. 6 p. Available online at http://www.crinigan.com/ensayos/girasol/INTA%20Villegas%200607.pdf

Aranda E, Sampedro I, Martín J, Delgado M A, Arriagada C, García-Romera I y Ocampo J A 2005 Disminución por hongos saprobios de la fitotoxicidad del alpeorujo seco y extractado. Optimización de su uso como fertilizante biológico y para control de hongos fitopatógenos. CAO01-008. Granada, España. Available online at http://www.expoliva.com/expoliva2005/simposium/comunicaciones/OLI-57.pdf

AraujoY, Luizao F and Barros E 2004 Effect of earthworm addition on soil nitrogen availability, microbial biomass and litter decomposition in mesocosms. Biology and Fertility of Soils 39(3): 146-152. Available online at http://www.springerlink.com/content/efuh7rcdgvtg07am/

Aseri G K, Jain N, Panwar J, Rao AV, Meghwal P R 2008 Bio-fertilizer s improve plant growth, fruit yield, nutrition, metabolism and rhizosphere enzyme activities of

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Pomegranate (Punica granatum L.) in Indian Thar Desert. Scientia Horticulturae 117(2): 130-135.

Benitez J, Vaneph S y Bot A 2002 Plantando conceptos y cosechando buenos resultados. Leisa Revista de Agroecología 18(3): 6-9.

Berc J, Muñiz O and Calero B 2004 Vermiculture offers a new agricultural paradigm. Biocycle 45(6): 56-57.

Bocchi S and Malgioglio A 2010 Azolla-Anabaena as a bio-fertilizer for rice paddy fields in the Po valley, a temperate rice area in northern Italy. International Journal of Agronomy. Volume 2010. 1-5. Available online at http://www.hindawi.com/journals/ija/2010/152158/

Bunch R 1994 El uso de abonos verdes por agricultores campesinos: lo que hemos aprendido hasta la fecha. Informe técnico N°3. 2ª ed. Honduras: Fundación Interamericana. Available online at http://www.cidicco.hn/archivospdf/Inftecnico3.pdf

Canales-López B 1999 Enzimas-algas: posibilidades de su uso para estimular la producción agrícola y mejorar los suelos. Terra Latinoamericana 17(3): 271-276. Available online at www.chapingo.mx/terra/contenido/17/3/art271-276.pdf 40

Canales-López B 2001 Uso de los derivados de algas marinas en la producción de papa. Tomate, chile y tomatillo: Resultados de investigación. Ponencia. Buenavista, Saltillo, Coahuila, 29 de octubre del 2001. Available online at http://www.uaaan.mx/academic/Horticultura/Memhort01/Ponencia_03.pdf

Celis J, Sandoval M, Zagal E y Briones M 2006 Effect of sewage sludge and salmon wastes applied to a Patagonian soil on lettuce (Lactuca Sativa L.) germination. Journal of Soil Science and Plant Nutrition 6(3): 13-25. Available online at http://www.scielo.cl/scielo.php?pid=S0718-27912006000300002&script=sci_arttext

Chen J H 2008 The combined use of chemical and organic fertilizers and/or biofertilizer for crop growth and soil fertility. International workshop on sustained management of the soil-rhizosphere system for efficient crop production and fertilizer use. Taiwan: National Chung Hsing University. Available online at http://www.agnet.org/library/tb/174/

Chhotu J and Fulekar M 2008 Vermicomposting of vegetal waste: a biophysicochemical process based on hydro-operating reactor. African Journal of Biotechnology 7(20): 41

3723-3730. Available online at http://www.ajol.info/index.php/ajb/article/viewFile/59420/47714

Chirinos J, Leal A y Montilla J 2006 Uso de insumos biológicos como alternativa para la agricultura sostenible en la zona sur del Estado Anzoátegui. Revi

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We kiss the soil as if we placed a kiss on the hands of a mother, for the homeland is our earthly mother. We consider it our duty to be with our compatriots in this sublime and difficult moment. Delima, SJ. Legaspina, C. Perez, MC. Zerrudo, JE. 20!6 researchers

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