CONFINED ANIMAL PRODUCTION AND MANURE NUTRIENTS

Using data from the Census of Agriculture on animal inventory and sales, we estimate manure nutrient production on farms with confined livestock. Using reported on-farm production of crops on these same farms, we estimate the nutrient uptake for major field crops and pastureland. This enables us to examine the balance between manure nutrient production and nutrient need measured by crop uptake at a farm level. Examination at alternative spatial scales, shows that 75 percent of counties in the U.S. have farms that produce more manure nutrients than can be assimilated on the farm of production (excess nitrogen).The vast majority of the counties that produce excess nitrogen have adequate land in the county to spread the manure at agronomic rates. Thus, proposed policies that focus on land application have the potential to limit manure nutrient movement to waterways in most areas, if properly managed. However, moving manure to crop farms that formerly had not used manure will increase costs. There were about 5 percent of counties where the manure nitrogen production levels from confined animal production exceeded half the nitrogen assimilative capacity of all the cropland and pastureland in the county. These areas have the greatest need for mechanisms to encourage off-farm solutions to utilize manure as a feedstock for commercial enterprises or central processing.Livestock Production/Industries,

Unexpected phase locking of magnetic fluctuations in the multi-k magnet USb

The spin waves in the multi-k antiferromagnet USb soften and become quasielastic well below the antiferromagnetic ordering temperature TN. This occurs without a magnetic or structural transition. It has been suggested that this change is in fact due to dephasing of the different multi-k components: a switch from 3-k to 1-k behavior. In this work, we use inelastic neutron scattering with tridirectional polarization analysis to probe the quasielastic magnetic excitations and reveal that the 3-k structure does not dephase. More surprisingly, the paramagnetic correlations also maintain the same clear phase correlations well above TN (up to at least 1.4TN)

CONFINED ANIMAL PRODUCTION AND MANURE NUTRIENTS

Census of agriculture data were used to estimate manure nutrient production and the capacity of cropland and pastureland to assimilate nutrients. Most farms (78 percent for nitrogen and 69 percent for phosphorus) have adequate land on which it is physically feasible to apply the manure produced onfarm at agronomic rates. (The costs of applying manure at these rates have not been assessed). Even so, manure that is produced on operations that cannot fully apply it to their own land at agronomic rates accounts for 60 percent of the Nation's manure nitrogen and 70 percent of the manure phosphorus. In these cases, most counties with farms that produce "excess" nutrients have adequate crop acres not associated with animal operations, but within the county, on which it is feasible to spread the manure at agronomic rates. However, barriers to moving manure to other farms need to be studied. About 20 percent of the Nation's onfarm excess manure nitrogen is produced in counties that have insufficient cropland for its application at agronomic rates (23 percent for phosphorus). For areas without adequate land, alternatives to local land application-such as energy production-will need to be developed.Manure, nutrients, manure nutrients, animal waste, confined livestock, confined animal feeding operation, CAFO, feedlot beef, dairy cows, swine, poultry, animal unit, manure nitrogen, manure phosphorus, water quality, Livestock Production/Industries,

5d-5f Electric-multipole Transitions in Uranium Dioxide Probed by Non-resonant Inelastic X-ray Scattering

Non-resonant inelastic x ray scattering (NIXS) experiments have been performed to probe the 5d-5f electronic transitions at the uranium O(4,5) absorption edges in uranium dioxide. For small values of the scattering vector q, the spectra are dominated by dipole-allowed transitions encapsulated within the giant resonance, whereas for higher values of q the multipolar transitions of rank 3 and 5 give rise to strong and well-defined multiplet structure in the pre-edge region. The origin of the observed non-dipole multiplet structures is explained on the basis of many-electron atomic spectral calculations. The results obtained demonstrate the high potential of NIXS as a bulk-sensitive technique for the characterization of the electronic properties of actinide materials.Comment: Submitted to Physical Review Letters on 31 December 200

Study of meteoroid impact into ablative heat shield materials Final report

Meteoroid impact damage to Apollo and Gemini ablative heat shield

Evolution of age and length at maturation of Alaskan salmon under size-selective harvest

Spatial and temporal trends and variation in life-history traits, including age and length at maturation, can be influenced by environmental and anthropogenic processes, including size-selective exploitation. Spawning adults in many wild Alaskan sockeye salmon populations have become shorter at a given age over the past half-century, but their age composition has not changed. These fish have been exploited by a gillnet fishery since the late 1800s that has tended to remove the larger fish. Using a rare, long-term dataset, we estimated probabilistic maturation reaction norms (PMRNs) for males and females in nine populations in two basins and correlated these changes with fishery size selection and intensity to determine whether such selection contributed to microevolutionary changes in maturation length. PMRN midpoints decreased in six of nine populations for both sexes, consistent with the harvest. These results support the hypothesis that environmental changes in the ocean (likely from competition) combined with adaptive microevolution (decreased PMRNs) have produced the observed life-history patterns. PMRNs did not decrease in all populations, and we documented differences in magnitude and consistency of size selection and exploitation rates among populations. Incorporating evolutionary considerations and tracking further changes in life-history traits can support continued sustainable exploitation and productivity in these and other exploited natural resources