On Solar Powered Nitrogen Factories

Plants and soils in nature fix their own nitrogen by
interacting with microbes via complex food webs. 

    Recently, I was invited into a discussion on the potential for "solar powered nitrogen factories".  The dialog dealt with using legumes and grasses as cover crops to increase soil fertility.  This is of course, a great strategy which farmers are adopting at large scales.  As the cover crops grow, they release sugars that feed soil microbes, nitrogen rich amino acids, and a long list of other good biomolecules into the soil.  Often, interplanting carefully selected cover crops with the main crop results can not only eliminate the need for chemical fertilizers and increase yields of the main crop, but also supplement the grower with a second "crop," the cover crop, which might be used to feed livestock directly, or to make silage.  As I listen to the success growers are having with cover crops, I cannot help but wonder how we ever bought into the myth that feeding plants only Nitrogen (ammonium sulfates, ammonium nitrates, etc.) or even N, P, and K, was a good idea.  We've understood nitrogen fixation for decades.

    Throughout my career, I've heard many discussions about the potential to engineer grain crops, like wheat, to fix their own nitrogen.  In the 80's, we spoke as though nitrogen fixing grasses were just around the corner.  Later, it seemed the process was more complex than initially imagined.   I shudder to think of the millions that have been invested in related research since the 1980's.  But in the era of the microbiome, scientists and growers are awakening to the reality that the biggest barrier to self-fertilizing plants may be the now-dogmatic belief that crops grow better when we add manufactured forms of nitrogen.  We have sorely underestimated a number of factors that work into the nitrogen availability formula.  We have failed to reflect adequately on the number of species that fix nitrogen, the impact our agrochemicals and tillage practices have on nitrogen fixation dynamics, and our own inability to accurately measure nitrogen fluxes in a dynamic living system.   We have also been blind to the reality that far too often, the nitrogen we add is what is making our crops prone to disease and weed infestations.  No wonder we are now looking for microbial alternatives.

    In terms of seeking microbes that serve as  solar powered nitrogen factories, it is important to consider cyanobacteria along with rhizobia.  These single celled algae include many strains that can fix nitrogen.  Because they are photosynthetic, they will be most abundant on soil and plant surfaces where the sunlight can reach  them. Like free living chloroplasts,  the contributions of cyanobacteria to soil carbon and nitrogen cycling are too often ignored in agriculture, probably because conventional horizontal tillage and fertilization practices render soil microbes incapable of doing their job.
    In a healthy soil, when nitrogen levels are low, both cyanobacteria and rhizobia increase (assuming other nutrient levels are adequate), and the system is supplied with converted atmospheric nitrogen.  However, when you add nitrogen fertilizers, these "factories" shut down, and when you plow the soil, you bury the cyanobacteria, rendering them incapable of growing and fixing nitrogen.

     Another problem created by adding nitrogen, especially from simple sources like ammonium or nitrate salts, is that doing so feeds soil microbes that "denitrify" the system.  As the number of denitrifying bacteria increase, your nitrogen gets released back into the atmosphere where it has no value at all for the plant.  The grower is quite literally throwing his or her money away.

   Because nitrogen in its various forms is both critical and potentially toxic to all living cells, nature regulates it carefully, and has devised numerous mechanisms to insure that plants get enough, but not too much.  When we work with these systems, rather than override them, it is very possible to grow crops without added N.  Remember, the air around us is more than 78% N!   Build the plant and soil microbiology, and N fertilizer becomes obsolete.

    We did not always believe N fertilizer was essential.  It's use became widespread after WWII, largely because the industrial giants who made millions off weapons development (TNT, etc) needed new markets that would endure in times of peace.  Large investments were made in 1) plant genetics to develop hybrids that could tolerate large amounts of nitrogen 2) demonstration plantings around the globe designed to illustrate orders of magnitude difference when N is added.

     Today, we know that the only way these differences would have ever been observed would have been on if field trials were made on nutrient depleted, microbial imbalanced soils.  (Read papers by Norman Borlaug, father of the green revolution).  Universities followed the money, and began teaching the use of nitrogen as the "right" way to grow crops.   This allowed them access to enormous streams of grant money, because the imbalances created by adding N created new problems to solve. 

     Hiding the truth, that a healthy soil can feed itself, served not to benefit the farmer, (how many farms have we lost since WWII) but to ensure jobs for academia, government, and agrochemical companies. Today's successful farmers are awakening, not only to the value of soil microbes and soil health, but also to the fallacies of institutions that serve big money under the disguise of public service.

Health and Economic Disparities are Created by Specialized, Fragmented Food and Healthcare Systems

   The 20th Century Moved Us Into a Specialized, Fragmented, Industrialized World.

     In the conservative1980's, as a student in the college of agriculture at New Mexico State University, I was engaged in frequent class discussions and debates regarding the loss of family farms, trends towards larger and more technologically advanced corporate farms, and the the need to address rapidly growing global populations.  At the time, we could scarcely comprehend that 4.5 billion people lived on our planet! New Mexico's population density was still below one person per square mile, and most of us in the ag college grew up in rural areas.  We were all made aware of the potential for a Malthusian catastrophe, which would be characterized by increasing disparities, high rates of disease, and widespread global conflict.  College professors often used this potential to justify the need for agricultural research, and most of us marveled at the steps that had been taken to avert catastrophe using green revolution technologies of the 1950's and 60's.  The conventional wisdom we absorbed in the university was that our agrochemical industry had spared us from catastrophe, and that we would continue to thrive as long as we continued to invest in technology.  

     A few of the older professors challenged this.  They were not well liked by their peers.  Like my uncles and aunts, most of whom were old enough to be my grandparents, these seniors seemed to believe that rural life in days past was much simpler, and much more fulfilling.  My peers dismissed "seniors" as simply being unable to keep up with the times.  I listened to both sides with an open mind, and looked for the middle ground.  Years simply had to pass before I could come to terms with the wisdom the older generation had to offer. 

In a specialized economy, disparities are common because the goods and services necessary for healthy and prosperous living are scattered.  Experts in medicine know little about nutrition.  Experts in human nutrition understand little about the environmental and industrial factors that impact how food is grown.  Employees focused on earning paychecks have little awareness of how their work environment is eroding their long-term health. 

    For the most part, agriculture (like industry in general) had migrated to a highly specialized, assembly line business model.  Machinery and chemicals had replaced human labor and biological defenses.  Generalist farmers who raised twenty kinds of vegetables, beef, milk, eggs, and fruit on a small farm were being replaced with corporate agricultural specialists, often subsidized by the government to plant (or not to plant) one or a few commodities.  Consumers were forced to change their shopping habits, because farms that once sold produce at roadside stands were replaced with supermarkets, and because with mom and dad now both working 40 to 80 hours a week, there simply wasn't time to drive out to Sam's melon stand and Sally's dairy.  Shoppers now needed a one-stop shop where all their household, food, and medical needs could be met.  Enter Wal-Mart. 

    Fast forward to 2015.   Global hunger statistics this century have hovered around 1 billion.  Despite, and perhaps because of, modern technology, these numbers are the highest in human history. In recent years, these numbers have fallen slightly, perhaps only because fighting and sickness in developing countries have reduced demands on failing global food systems.  

      Although costs of computers and other technology have dropped steadily since the first time I bought a personal computer, the pound of fresh fruit I paid $0.29 for in 1985 now costs $2.45.  And like many of my peers, I suffer from an illness which appears to have been caused, at least in part, by nutritional imbalances stemming from years of consuming the products of the very technologies we were so proud of in the 80's. You see, when we were learning how to spray crops with pesticides, fertilize soil with ammonium nitrate, propagate thousands of clonal plants in vitro, engineer novel genes into crops, and package our clean, harvested corn into shrink wrap packages that could cross oceans and still look fresh in the supermarket, we were also altering the invisible, nutritionally complex microbiomes (microbial communities) that populated our soils, nurtured our crops, colonized our intestines, and worked with our immune systems to keep us healthy. 

The Task for Survivors in the 21st Century Will be to Foster Generalized, Holistic Living.

     In the end, life is nothing more than a school of hard knocks, and the degrees we earn through experience are far more meaningful than those we pay for with tuition.  As we watch the global news today, observe the trends in violence, stock markets, commodity price trends, disease trends, weather patterns, stagnant legislative processes, and widespread economic paralysis, we are all aware that business as usual is not cutting it, and changes promised by politicians only amplify problems. But many are looking to our seniors, our ancestors, our traditional spiritual leaders, and our indigenous cultures, recognizing that the old ways these people have clung to endure because they are sustainable.   We've long since forgotten the Sony Walkman, and Apple IIe, all the rage back in the 80's.  But we still eat, and local farmers markets are actually growing in popularity.  After decades of cutting funds for vocational programs, high schools are re-introducing agriculture and mechanical arts, as if administrators have suddenly figured out that eating is a relevant activity for future generations. 

     For perhaps the first time, college graduates are taking a keen interest in home food production.  Professionals are going home to feed the chickens or weed the gardens, and in doing so, they are finding the stress reducing mental health benefits that can only come from time spent outdoors.  Bloggers reporting recovery from devastating, even life threatening illnesses share stories of recovery based on alternative methods that involve everything from herbal remedies to visits with shaman and curanderas.  Specialized experts who stumble into these accounts are shocked, even horrified, to hear reports of success from such primitive approaches.  Why wouldn't they be shocked?  Many have invested their careers to proving that modern technologies make lives better. But the fact is, most technologies make our specialties better, and each time our life becomes more specialized, it also becomes more difficult to access those things we need to sustain ourselves and our families.

     Learning to live holistically is invaluable.  From an economic perspective, it reduces the cost of living.  When all we need is close to home, it is also easier to afford.  From a health perspective, it is less stressful, because we simply don't have to reach so far to find the products or the expertise we need to survive. This is why people in the 21st century will need to develop more holistic lifestyles.  Lifestyles, primary health care, and careers will be closer to our families, safer, and more transparent. We will work less for strangers, and more for those whose lives are entwined in our own:  our children, our spouses, and those we love.  Victory gardens will resurface as the key to good health, sustainable communities, and sound fiscal management. Schools will be centered within the community, and parents voices will be reflected in the curriculum.   Our children will not be surrendered to strangers to teach.  

     Of course, there will be many who reject these changes, and cling to the large industrial centers and government agencies that keep resources and people separated.  I wish them well as I move to a world where their efforts are less relevant.