Archive Article: November, 2009
One of the most impassioned topics currently discussed in the mainstream media is that of sustainability. It would appear that this concept is new and novel due to the intense interest it has garnered by all engaged in the dialogue. However, it may be surprising to some that the fundamental practices are centuries old. I have lectured on this topic for nearly 10 years and have distilled down a definition that I feel is broad enough to encompass the concepts covered in this article while allowing the reader to interpret and subsequently tailor the message to his or her life. Sustainability as I have come to understand it is the act of producing all of the necessities for life in a manner that does not degrade the quantity or quality of resources for future generations. This is not to say the aforementioned resources cannot be amended or modified but their quality and quantity must not be degraded. This may appear to be a tall order for many of us who have been raised in a “single use” society. The notion of “no net loss” requires a dramatic change in our behavior as well as a nearly wholesale replacement of the traditional agriculture model.
Pisac, Peruvian terraces in the Sacred Valley.
For us to truly understand and ultimately discuss sustainability with a level of competence it is important to understand its genesis and its consequent evolution throughout history. What makes the concept of sustainability unique is that it is actually a myriad of symbiotic, yet often disparate, applied concepts, anchored to a very specific set of beliefs. Therefore, it is not a singular idea but a complex paradigm that many previous civilizations employed; and through its implementation they enjoyed great wealth and prosperity. By using sustainable practices the Incas and the Aztecs were able to support populations that many estimate were in the millions. Imagine the food security burden associated with a population of that magnitude and then factor into the equation that these civilizations lived at altitudes with very little precipitation, long before the industrial revolution. Accomplishing these feats of agricultural sustainability was nothing short of miraculous. How were these civilizations able to conquer this apparently insurmountable task? The answer is relatively simple; through sustainable agriculture. Mesoamerican inhabitants developed more than half the agricultural products that the world eats today. Among these are more than 200+ varieties of potato; 20+ varieties of corn; as well as varieties of beans, peppers, squash, quinoa and amaranth.
The Incan culture is responsible for developing agricultural techniques and methods so effective that many of them are still in use today. Arguably the most recognizable Incan method used in their sustainable model was the construction of andene terracing. These terraces were often constructed in a circular fashion and employed regional topography to their advantage as they were built on natural slopes. This design allowed the passive force of gravity to irrigate their crops without the use of mechanical pumps. The faces of the slopes were waterproofed by tiling the surface with a mosaic of flat impervious rocks. Upon this stone foundation, walls and terraces were constructed with multiple water inlets along the top and several drainage channels at the bottoms. These voids were filled with mineral rich soils and amended with nitrogen rich seabird and bat guano as well as coarse aggregate and sand at the bottom to aid in drainage. Sound familiar? The overall design combines many of the fundamental elements currently employed in contemporary hydroponic systems: The use of automated irrigation, the circular design to maximize space, upper terraces feeding lower terraces and the use of organic fertilizers and drainage amendment to maximize yield.
A second lesser known Incan design was the Waru Waru; this system was constructed on high flat plateaus, where terrace construction was not possible or where direct precipitation was the only available irrigation method. Deep water ditches were excavated around the agricultural plots and were subsequently filled with rain water. These channels served as reservoirs for irrigation but they also created a humid rich microclimate due to evaporation. This is of paramount importance for one of the greatest challenges of cultivation at elevation is the lack of humidity. Many of us involved in this industry design our products to excel in controlled environments and as a result humidity is one of the most critical factors that we address. Amazingly enough, the Incans were able to accomplish this task 500 years ago, at 14,000 feet of elevation, without humidifiers or fuzzy logic controllers.
The Incans were also dedicated to research and development as it applied to plant morphology and genetic resistance. To this end they constructed an exceptionally large circular terrace in the Peruvian city of Cusco. Experts believe that this location is where most of the hybridizing experiments took place and as result of the massive scale of this operation, hundreds of Incan farmers were employed year round to ensure that the desired outcome was achieved. By constructing this massive terrace system the Incas were able to replicate the conditions found at various elevations and consequently develop elevation specific hybrids. By using this technique the Incas were able to develop varieties of maize and potato that grew at 14,000 feet amsl (average mean sea level) that were previously only cultivated successfully at 3,000 feet amsl.
On a related note, it is evident from archaeological investigation that the Aztecs constructed massive aquaponic farms by raising fish alongside crops. They built artificial islands known as chinampas in regionally low lying areas (marshes or lakes) and planted them with a variety of regional crops. Canals were then constructed throughout this network of islands and afforded the farmers the ability to tend their crops from a canoe. Waste from the fish fell to the bottom of the canals and was collected to fertilize plants. Plants also benefited from the microclimate created by the evaporating water.
It should be obvious by now from this crash course in Mesoamerican agriculture that the solution to our sustainability problem with regards to agriculture has already been defined over 500 hundred years ago. Our charge now, as members of the hydroponic community, is to take these concepts and extrapolate them into forms and techniques that are applicable to modern controlled environment agriculture. Detractors to this cause cite that the current sustainable practices are not viable when expanded to the magnitude necessary to provide the quantity and quality of food needed to sustain the global population. Ironically, I agree with this assessment, however, I am not deterred but inspired. As a global community we have been given a once in a lifetime opportunity to mold the future through environmentally conscious food production. The models currently employed are broken and do not incorporate technological advancements available in other industries. The hydroponic industry has a tendency to be a bit incestuous with regards to solutions to our internal problems. This is not only reasonable but expected for many of the suppliers to our industry have a vested interest in their proprietary technologies. Unfortunately, it is this short sighted, margin-based approach to technological development that has placed us at the precipice. Many experts believe that without a means of sustainable agriculture we will exceed our planet’s carrying capacity by 2050. These are dire times and we must adopt a sense of urgency. We have an opportunity to make a difference and we must embrace it. Instead of accepting the broken and inefficient technologies we are given with a willing look and open hands, we must demand that the industry designs future products with sustainability in mind. It all starts with the growers; we are the inventors, we are the solution and we can drive this agenda, but we must remain steadfast in our resolve. We must commit to products that can be recycled or used as fuel for another process. We must abandon technologies that are inefficient to ship and manufactured thousands of miles away. We must train a critical eye on those who supply our nutrients. Are they mining these constituents in an environmentally sound fashion or are they buying low and selling high with no regard to impact they cause? We must be judicious in our approach to irrigation; drain-to-waste must be reevaluated and new re-circulating designs must be developed. Finally, our current lighting options must be reexamined and revamped with not just lumen intensity and wattage in mind but with energy efficiency (watt to usable lumen ratio), functional life span and recyclability calculated into the equation. In the end this is our responsibility and our planet; we can accept what the talking heads tell us or we can prove them wrong. This is the event horizon!
