Agroecology Experience
El Salvador
June-July 2007

by Antonio Escandon

     The educational experience I encountered while in the country of El Salvador was an interesting one. One project I visited seemed to be promising. This project works in conjunction with the environment to reclaim used water to irrigate crops that can feed livestock. The water comes from the El Regimineto de Caballeria of San Juan Opico which houses approximately 600 men and 80 horses. This is a branch of El Salvador's Army.

     The project aims also at assessing the storage of water that can be utilized during the dry season. The country's decrease in precipitation during the months of November through April makes El Salvador a perfect candidate. Florida International University's (FIU) Applied Research Center (ARC) has designed a "constructed wetland" which can treat used water. Through a filtration process, used water is treated; subsequently, it is suitable for re-use.

     I learned that a wetland can occur naturally and it is an environment that consists of a terrestrial ecosystem and an aquatic system which are co-dependent on one-another.
     The constructed wetland designed by the School of Engineers at FIU fulfilled this definition. It also supported the concept of sustainability at the ecological level. This is accomplished as water passes through a network combination of gravel and diverse plant's roots without the deployment of any environment disruptive agents.
     The wetland utilizes a 1- acre area which provides a home and biome for plants, birds, frogs and microorganisms. In addition, plants in the constructed wetland make use of human wastes such as nitrogen, phosphorus (contained in urine and feces). As these elements pass through the plant roots they become available to plants as food. Plant roots uptake the necessary elements and nutrients. Some plants had better ratios of uptake for which data was collected. The rational employed here was to evaluate the most efficient plant(s).

     The project is very promising to El Salvador because the country has a period of dry season. This has the potential to permit the country to irrigate crops during this time which has the potential to empower the economy of El Salvador with a comparative advantage which it does not possess at the present time.

     I learned that water is kept in constructed pools. These storage devices are lined-up with a plastic which avoids the water from percolating to underground water (see picture 1). Percolation of water is a potential problem with a system of such big proportions. Concerns of contaminating the manto freatico thus are reduced in almost its entirety. A potential problem that was not assessed is the accumulation of sediments over time. The life-time of the project must be assessed also to calculate the cost to clean the sediments. This was of great importance to me because I could see how the benefit (storage of water) outweighs potential problems (sediment building). This is data to design perhaps a dismountable sediment collector which has the potential to be used as natural fertilizer (natural carbon) which can increase the profitability of the project.

Picture 1. Basin one receives all reclaimed water from
Cavalry while avoiding percolation of water.

     The water travels its way from the cavalry through a series of pipes that end in the basin depicted above. It is in here where this untreated water is sent to the Artificial Wetland for cleaning (filtration) purposes. The water goes through a process of filtration made of plant's roots and gravel (see Figure 1).

Figure 1. Artificial Wetland uses the roots of plants
anchored in gravel as a filter.

     The Constructed Wetland (CW) is eco-friendly. It uses engineering design, Global Water instruments, specific plants and human monitoring to accomplish the goal, "the reclamation of water."
The selection of plants was conducted by the Agronomers at the Centro Nacional de Tecnologia Agropecuaria y Forestal (CENTA) of El Salvador. Different plants were used as their diverse foliages allow for different indexes of evapo-transpiration due to surface area (picture 2).

Picture 2. Differences in surface area due to foliage area.

     In summary, the CW serves a triple purpose. First, it provides a biome for wild life. Second, it acts as a buffer zone between pathogen-rich water, human wastes (feces, etc) and a surrounding human settlement (Cavalry). And third, it treats reclaimed water making it suitable for irrigation purposes.

     El Salvador reminded me of my own country, Chile, back in the 1980s. That is, the country has a potential for growth with its fertile lands but poverty and crime reign. There is a systemic fear of gangs which was evident in all people who I came in contact with. During my visit to the City of San Salvador I came in contact with city contamination, smog, dirty streets but common people who still can manage to smile and be hospitable under such circumstances. Their spirit of fight against such adversities and their human-capital are remarkable. During my visit and stay at the Centro Nacional de Tecnologia Agropecuaria y Forestal (CENTA) I came in contact with Agronomers who introduce me to the world of agriculture. All their teachings reinforce my beginnings in plant biology back in elementary school. I learned for instance of the crucial role that honey bees play in agriculture as well as how to avoid erosion utilizing grass planted at the end of planting areas, just to name two. The overall experience was a positive one. Although I am familiar with Latin America, this trip reinforced my own roots as I saw El Salvador in reflection to the land where I was born and where I am today. In other words, it made me uncomfortable to realize that still today in 2007 people still survive under such bad human conditions.

This project has been made possible by a funding support under the USDA CSREES ISE Grant Program.
USDA-CSREES Grant Number 2006-51160-03409.