Monday, August 16, 2010
Saturday, March 21, 2009
Its True. I'll be putting my soil science blogging energy elsewhere for the forseeable future: http://nscss.org/blog/207. Admittedly, not a pretty name, not like Transect Points: views from the underground. Might have to make an url alias.
Tuesday, December 16, 2008
The International Center for Soil Fertility (IFDC) reports that, with the exception of potash, world fertilizer prices have dropped dramatically.
Gregory explains why fertilizer prices fell so rapidly in late 2008. "The high fertilizer prices caused 'demand destruction.' Farmers were unable or unwilling to pay two or three times the prices of early 2007." Collapse of the global credit market, a trade recession, and slowdown in world economic growth worsened the situation. Demand for fertilizers fell and stocks accumulated. Fertilizer manufacturers cut back on production.
"But potash prices have stayed high due to its shortage and difficulties in transporting Russian potash because of an enormous and expanding sinkhole near the Silvinit mines," Gregory says. "Demand for potash increased from 2006 through 2008, and potash inventories are now 37% lower than over the past 5 years."
A couple of thoughts I will be researching.
First, if lower demand has translated to lower utilization, this should show up as reduced inventories of 2008 commodity crops, like rice, soybeans, and wheat, and reduced supply of perishable fruit crops like bananas.
Second, with fertilizer prices now low, this would be a excellent time to replenish African soil fertility, currently in crisis. Especially in consideration of a possible reduction in 2009 food inventories world wide.
(recycled from nscss.org)
Calling all experimental hydropedologists. A vast room of poster presentations greeted thousands of scientists at the American Geophysical Union’s annual autumn meeting on Dec. 15 in San Francisco – including one announcing an “experimental hydrology Wiki” website. The wiki was created last year by Llja Tromp-van Meerveld of Simon Fraser University in Burnaby, British Columbia and Theresa Blume of the University of Potsdam in Germany. Originally designed to meet the needs of doctoral students, the wiki is now open to assist a range of environmental researchers, from hydrology to related fields in science and engineering. And hydropedology. The website is: www.experimental-hydrology.net. Soil moisture is used as a prominent, and encouraging, example.
(recycled from nscss.org)
Saturday, December 13, 2008
In a previous post I provided an oblique link to a news release: Climate Change Alters Ocean Chemistry. It makes reference to conditions resonating with the theory of biorhexistacy:
- The research team, which included Caldeira, Elizabeth M. Griffith and Adina Paytan of the University of California, Santa Cruz, plus two other colleagues, studied core samples of deep oceanic sediment recovered from the Pacific Ocean Basin. By analyzing the calcium isotopes in grains of the mineral barite in different layers, they determined that between 13 and 8 million years ago the ocean’s calcium levels shifted dramatically. The shift corresponds to the growth of the Antarctic ice sheets during the same time interval. Because of the huge volume of water that became locked up in the ice cap, sea level also dropped.
“The climate got colder, ice sheets expanded, sea level dropped, and the intensity, type, and extent of weathering on land changed,” explains Griffith.
“This caused changes in ocean circulation and in the amount and composition of what rivers delivered to the ocean,” adds Paytan. “This in turn impacted the biology and chemistry of the ocean.”
These folks are saying that momentous changes in oceanic chemistry recorded in the sediment record must have been predicated by equally momentous changes in soil chemistry, changes tied to both atmospheric carbon dioxide content and climatic conditions.
From a pedologist's view, it is clear that under the expanded humid, warm, stable conditions envisioned by H. Erhart for biostasis, we would see deeper residual soils and more rapid formation of argillic horizons. In terms of soil taxonomic orders (USDA), more intense chemical weathering would cause the expansion of inceptisols at the expense of mollisols, ultisols at the expense of alfisols, and oxisols at the expense of ultisols.
Caldeira and company tie warm climate to higher river calcium content, but strongly implicate higher atmospheric carbon dioxide as the primary driver of increased chemical weathering. Atmospheric carbon dioxide levels do not appear to be part of Erhart's construct, but could certainly enhance these pedogenetic trends.
Acid rain alarm bells are ringing faintly in the distance at this point. But it is a false alarm. Rain water pH is due mostly to equilibrium with atmospheric carbon dioxide. The carbonic acid formed buffers rain drop pH to 5.6, and higher atmospheric carbon dioxide increases the carbonic acid content, but it doesn't lower pH below 5.6. Other constituents accomplish that. Thus increased atmospheric carbon dioxide isn't being implicated in some futuristic acid rain scenario.
Oxisols, ultisols and spodosols would increase in extent with increased soil weathering. But could it also mean lower plant disease, and more nutritious crops? Increased carbonic acid would drive faster pedogenesis, as would increased the biological activity stimulated by higher carbon dioxide. For soil, that would mean a richer solute content in the soil water, more rapid formation of secondary minerals, more eluviation or translocation of minerals with percolation. To the list of pedological shifts at the soil order level, we can add the expansion of spodosols at the expense of inceptisols.
Something very positive can be expected for soil that is not captured in the shifting soil order paradigm. For plants and soil microbes, richer solute content would mean greater availability of mineral nutrients. In soil husbandry and slow food circles, higher mineral availability translates to healthier soil, lower plant disease, and more nutritious harvests. What the shifting soil order paradigm does signal is that soils will be at greater risk of losing their fertility to leaching. Having the soil chockablock full of biochar will be essential to mitigate this last effect. Let's start now.
(Recycled from nscss.org)