Soil organic carbon studies in semi-arid tropical India: Sources and stabilization
As organic material decays, it stabilizes in soil and then plays a critical role in holding water and nutrients available for plant growth and in supporting soil structure. Management of soil organic matter (SOM) is essential in the semi-arid tropics (SATs) characterized by savannah vegetation and soils with low SOM and low nutrient reserves. Properly managing SOM may increase soil organic carbon (SOC) sequestration, nutrient availability, soil moisture retention, and increased crop productivity.
This dissertation research (1) investigated the effects of diverse sorghum (Sorghum biocolor L. Moench)-based cropping systems and of conservation agriculture practices on SOC accumulation and its vertical distribution (Study 1); (2) assessed the short-term (16-months) soil C, and C fraction responses to conservation agricultural management practices in semi-arid tropical Vertisols (Study 2); (3) applied and evaluated selected aspects of geostatistics (Study 3); and (4) investigated and quantified the uncertainty presented by both measured and modeled SOC pools (Study 4).
In general, the key findings of the studies showed that diversified sorghum-based cropping system with minimum tillage and farm yard manure (FYM) treatment contributed to increased C storage within the soil profile. The addition of FYM had the most positive effect on C storage as a result of several factors as indicated by stable C and N isotopes and C values. Within the 16 month study, a slow increase of soil C was evident in increased C associated with the 2000-212µm size class.
Utilizing geostatistics, information about the pattern of spatial autocorrelation can be used to determine the sampling density required for achieving a given accuracy of the estimation of the mean concentration of SOC. The effect of the sampling density was quantified using power functions computed for different detection limits. Finally, the investigation of measured and modeled SOC pools showed that the measured SOC pools did not have the properties in the tested soils and land use combinations assumed by any of the models.
These findings demonstrate the importance of biogeochemical C cycling at various depths within the soil profile in semi-arid tropical Vertisols using conservation agricultural management practices; and management options that enhance soil C accumulation in nutrient limited soils. Further, this research increases our understanding of applications of geostatistics to soil properties for purposes of increased efficacy of sampling protocols for C in semi-arid tropical Vertisols. The research also showed that there were real differences regarding assumptions in the models compared to the measurement methods in SOC pools. No decisions could be made using the models, but the measurements confirmed likely SOM, conservation agricultural management strategies for semi-arid tropical Vertisols.
Anything new about stirling engines in Cal?
Looking for an update. Everything I find from google news is almost a year old. This is from the stirling engine deal with Southern Edison to build a 500MW plant outside of LA.
What geographical areas are best suited for a solar dish farm?
The southwest region of the United States is ideally suited for this. In fact, a solar farm 100 miles by 100 miles could satisfy 100% of the Americaâs annual electrical needs. Solar technology primarily addresses the peak power demands facing utility companies in the Southwest U.S. and other solar-rich areas.
The cost of living and job markets are better than the national average, but the best job strategy is not to go for averages, but look at your specific skills and experiences, figure out which careers that relates to, and then go to that geographical area:
technology - Silicon Valley
finance - New York
There are other factors to consider. How important are mountains? the ocean? good weather? I have met many midwesterners in Acapulco during the winter, and none ever told me
"I got to get back to Omaha. I just miss those snow covered plains."
4,000 Year Old Greenlander
WASHINGTON (Reuters) â Scientists have sequenced the DNA from four frozen hairs of a Greenlander who died 4,000 years ago in a study they say takes genetic technology into several new realms.
Surprisingly, the long-dead man appears to have originated in Siberia and is unrelated to modern Greenlanders, Morten Rasmussen of the University of Copenhagen and colleagues found.
"This provides evidence for a migration from Siberia into the New World some 5,500 years ago, independent of that giving rise to the modern Native Americans and Inuit," the researchers wrote in Thursday's issue of the journal Nature