How Fertilizers have Shaped Trade

In our blog posts we have discussed different technologies which have shaped the way food travels around the world.  Many of these advances have resulted directly from the industrial revolution and our understanding of fossil fuels.  Fertilizers are no different.  For this post I want to focus on fertilizer’s part in food production and how it relates to traveling food.
Fertilizer has always been an important aspect of farming.  For any plant to grow, they need sunshine, air, water and nutrients.  In farming, one thing which can be lacking are nutrients in the soil.  For crops, the essential nutrients needed are mainly Nitrogen, phosphate, and potash.  In more naturally occurring vegetation, soil is rejuvenated with these nutrients mainly by the death of plants and other wildlife.  The organic material decomposes and returns the nutrients back to the earth. Unfortunately, the soil on farms does not go though this same cycle (farmers rarely let their crops die).  This means the soil must be rejuvenated through other means.  This is where fertilizer comes in. 
Fertilizer is added to soil, providing crops with more nutrients to grow.  Traditionally, farmers have worked natural fertilizers and mined minerals (minerals with Nitrogen, phosphate, and potash) into their soil to provide their crops with more nutrients.  However, these methods have always been limiting.  Organic material takes time to decompose to a point which is useful, natural fertilizers have limited amounts of the needed nutrients, and before the industrial revolution mining had always been a hard and slow process compared to current standards.
When the industrial revolution hit, scientists discovered they could create nutrients used by plants in a lab.  This changed farming completely.  Now using synthetic fertilizers, farmers only need to sprinkle it on the ground, add water, and the soil is rejuvenated.  Not only did this make farming much easier, but it also increased a farms productivity.  Since these breakthroughs in fertilizers, people have enjoyed an amazing surplus of food.  Around 30 to 50%, of the food now grown can be attributed to these new types of fertilizers.
Fertilizers and Trade:
On the surface, this sounds great.  More food means less people go hungry around the world.  However, history has shown once certain problems are remedied, other's are created.  After World War II synthetic fertilizers started to become widely used.  This increase in synthetic fertilizer usage has also grown in parallel with world population. With more people on the planet, there is more demand for food.  
In my opinion, the increase in demand and supply of food has helped create the environment of trade we are looking at today.  With more people on the planet in combination with globalization, the amount of items changing hands (including food) is greater than it has ever been.  Any system of trade through history has never been perfect.  But, when trade happens at such a large scale, the problems which come with it are larger as well.