14,719 research outputs found
Hydrographic observations in Elkhorn Slough and Moss Landing Harbor, California, October 1970 to November 1971. Annual report, Part 3, July 1972
In October 1970, Moss Landing Marine Laboratories began an observational program to determine/the seasonal changes in the water chemistry of Elkhorn Slough and Moss Landing Harbor. This data report contains the first year of data (October 1970 - November 1971). These data are of immediate interest in determining the flushing and mixing mechanisms of
the slough and in establishing the effect that local domestic and industrial effluents have on the distribution of these chemical parameters. (Document contains 78 Pages
Increased Productivity of a Cover Crop Mixture Is Not Associated with Enhanced Agroecosystem Services
Cover crops provide a variety of important agroecological services within cropping systems. Typically these crops are grown as monocultures or simple graminoid-legume bicultures; however, ecological theory and empirical evidence suggest that agroecosystem services could be enhanced by growing cover crops in species-rich mixtures. We examined cover crop productivity, weed suppression, stability, and carryover effects to a subsequent cash crop in an experiment involving a five-species annual cover crop mixture and the component species grown as monocultures in SE New Hampshire, USA in 2011 and 2012. The mean land equivalent ratio (LER) for the mixture exceeded 1.0 in both years, indicating that the mixture over-yielded relative to the monocultures. Despite the apparent over-yielding in the mixture, we observed no enhancement in weed suppression, biomass stability, or productivity of a subsequent oat (Avena sativa L.) cash crop when compared to the best monoculture component crop. These data are some of the first to include application of the LER to an analysis of a cover crop mixture and contribute to the growing literature on the agroecological effects of cover crop diversity in cropping systems
The Potential Impact of the Great Recession on Future Retirement Incomes
Estimates the effects of job loss, slower wage growth, and withdrawals from retirement savings during the 2007-09 recession on retirement incomes at age 70, including decline in income by age group and number of those likely to live in poverty at 70
Cultivar diversity as a means of ecologically intensifying dry matter production in a perennial forage stand
The relationship between genotypic diversity and productivity has not been adequately explored in perennial forage production systems despite strong theoretical and empirical evidence supporting diversity\u27s role in ecosystem functioning in other managed and unmanaged systems. We conducted a two-year field experiment with six cultivars of an agriculturally important forage grass, Lolium perenne L. (perennial ryegrass). Dry matter production of L. perenne and the weed community that emerged from the soil seed bank were measured each year in treatments that ranged from cultivar monocultures to three- and six-way cultivar mixtures, all sown at a constant seeding rate. Mean L. perenne dry matter production increased with increasing cultivar diversity and was highest in mixtures that contained cultivars representing the greatest additive trait range (calculated on rankings of three traits: winter hardiness, heading date, and tolerance to grazing). Mixtures had greater yields than those predicted by the mean of their component monoculture yields, but there was evidence that highly productive cultivars may have dampened over-yielding in mixtures. Weed abundance was correlated with L. perenne dry matter, but not L. perenne cultivar diversity. These results suggest that multi-cultivar mixtures may have utility as an approach to ecologically intensifying perennial forage production. Additional research will be necessary to determine the mechanisms responsible for the over-yielding observed in this study and the generality of these findings
Interpreting the Constitution from Inside the Jury Box: Affecting Interstate Commerce as an Element of the Crime
Review of Harry Franqui-Rivera, Soldiers of the Nation: Military Service and Modern Puerto Rico, 1868β1952
Multicultural Commemoration and West Indian Military Service in the First World War
West Indian military service in the First World War is recalled in many settings. During the war race and class boundaries of colonial society was temporarily eroded by visions of imperial unity, but quickly by post-war assertions of imperial authority. However, recollections of wartime sacrifices were kept alive by Pan-African, ex-service and emerging nationalist groups before being incorporated into independent Caribbean national identity and migrant West Indian communities.
During the centenary commemorations, West Indian participation has increasingly been mediated through literature, theatre and broadcasting. Spheres of conflict which provided more heroic visions, such as the Middle East or the Taranto mutiny, have acquired particular symbolic importance, contrasting with the more tragic representations of the war as a whole
Boomers' Retirement Income Prospects
Examines how changing demographics and patterns in lifetime earnings, pension participation, and wealth accumulation among Americans born between 1946 and 1964 will shape baby boomers' economic well-being at age 70
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