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Showing posts from June 30, 2013

The last chapter: Industrial agriculture

As I have argued in the previous three blogs, industrial agriculture is the largest human project that impacts the Earth more broadly than any other human activity.  One needs to keep in mind that compared with the global environmental impacts of industrial agriculture, a Macondo well-like blowout is a child's play.  I know it, because I co-wrote a book on this subject with the famous historian and archeologist, Joe Tainter.  For example, in the Amazon forest the underbrush fires set by humans affect 3 million square kilometers, an area of India.  See NASA for a summary of this global catastrophe . Researchers for the first time mapped the extent and frequency of understory fires across a study area (green) spanning 1.2 million square miles (3 million square kilometers) in the southern Amazon forest. Fires were widespread across the forest frontier during the study period from 1999-2010. Recurrent fires, however, are concentrated in areas favored by the con...

Satellites confirm: Industrial-scale agrofuels are not viable

The proper mass balance of carbon fluxes in terrestrial ecosystems, described in Appendix B of my OECD paper (2007), confirms the compelling thermodynamic argument that sustainability of any ecosystem requires all mass to be conserved on the average. The larger the spatial scale of an ecosystem and the longer the time-averaging scale are, the stricter adherence to this rule must be. Such are the laws of nature. Physics, chemistry and biology say clearly that there can be no sustained net mass removal from any large ecosystem for more than a few decades. A young forest in a temperate climate, shown in the previous blog , grows fast in a clear-cut area and transfers nutrients from soil to the young trees. The young trees grow very fast (there is a positive net primary productivity or NPP ), but the amount of mass accumulated in the forest is small. When a tree burns or dies some or most of its nutrients go back to the soil. When this tree is logged and hauled away, almost no nutr...

Net Ecosystem Productivity is Zero on Planet Earth

In the last bog , I told you how the law of mass conservation governs the large-scale behavior of Earth's households - ecosystems - that must recycle all mass on average and export only low quality heat into the cold universe.  Now, I will give you a few useful definitions of cyclic processes, sustainability, and ecosystem productivity. Let me start from stating the obvious:  We live in a spaceship we cannot leave, a gorgeous blue, white and green planet Earth that takes us for a spin around her star, the Sun, each year. But this statement is imprecise. We really live on a vanishingly thin skin of the Earth, her ecosphere .   Think of this skin as of a thin delicate membrane, teaming with life and beauty, but incredibly fragile. We trample on this membrane and poison it.  Then we act surprised when it brakes and shrivels. Practically all life on the Earth exists between two concentric spheres defined by the mean Earth surface at the radial distance ...