72 research outputs found
Religious Folk-Songs of the Southern Negroes
Odum, Howard W. "Religious Folk-Songs of the Southern Negroes." PhD. diss., Clark University. *American Journal of Religious Psychology and Education,* vol.3, pp 265-365. July, 1909. http://hdl.handle.net/10428/2992.This is a reprint of Odum's 1909 dissertation for Clark University which first appeared in the American Journal of Religious Psychology and Education. This reprint seems to have been done in the same year and is thus one of Odum's earliest publications. This book has been more recently reprinted but this is the original. Odum was only 26 at the time he wrote this work based on his extensive field work for a number of years. He would later publish a number of important early works on African-American music
Estuaries
In the following an attempt is made to outline the specific problems of modelling of estuaries as characterized by the discharge of fresh water into a partially enclosed sea water body. The hydrodynamical regime and exchange mechanisms encountered in estuaries lead to specific chemical, biological and geological processes requiring
specially adapted models
A Net Energy Analysis of the Global Agriculture, Aquaculture, Fishing and Forestry System
The global agriculture, aquaculture, fishing and forestry (AAFF) energy system is subject to three unsustainable trends: (1) the approaching biophysical limits of AAFF; (2) the role of AAFF as a driver of environmental degradation; and (3) the long-term declining energy efficiency of AAFF due to growing dependence on fossil fuels. In response, we conduct a net energy analysis for the period 1971–2017 and review existing studies to investigate the global AAFF energy system and its vulnerability to the three unsustainable trends from an energetic perspective. We estimate the global AAFF system represents 27.9% of societies energy supply in 2017, with food energy representing 20.8% of societies total energy supply. We find that the net energy-return-on-investment (net EROI) of global AAFF increased from 2.87:1 in 1971 to 4.05:1 in 2017. We suggest that rising net EROI values are being fuelled in part by ‘depleting natures accumulated energy stocks’. We also find that the net energy balance of AAFF increased by 130% in this period, with at the same time a decrease in both the proportion of rural residents and also the proportion of the total population working in AAFF—which decreased from 19.8 to 10.3%. However, this comes at the cost of growing fossil fuel dependency which increased from 43.6 to 62.2%. Given the increasing probability of near-term fossil fuel scarcity, the growing impacts of climate change and environmental degradation, and the approaching biophysical limits of global AAFF, ‘Odum’s hoax’ is likely soon to be revealed
Estimates of new and total productivity in central Long Island Sound from in situ measurements of nitrate and dissolved oxygen
Author Posting. © The Author(s), 2013. This is the author's version of the work. It is posted here by permission of Springer for personal use, not for redistribution. The definitive version was published in Estuaries and Coasts 36 (2013): 74-97, doi:10.1007/s12237-012-9560-5.Biogeochemical cycles in estuaries are regulated by a diverse set of physical and
biological variables that operate over a variety of time scales. Using in situ optical sensors, we
conducted a high-frequency time-series study of several biogeochemical parameters at a mooring
in central Long Island Sound from May to August 2010. During this period, we documented
well-defined diel cycles in nitrate concentration that were correlated to dissolved oxygen, wind
stress, tidal mixing, and irradiance. By filtering the data to separate the nitrate time series into
various signal components, we estimated the amount of variation that could be ascribed to each
process. Primary production and surface wind stress explained 59% and 19%, respectively, of the
variation in nitrate concentrations. Less frequent physical forcings, including large-magnitude wind events and spring tides, served to decouple the relationship between oxygen, nitrate, and
sunlight on about one-quarter of study days. Daytime nitrate minima and dissolved oxygen
maxima occurred nearly simultaneously on the majority (> 80%) of days during the study period;
both were strongly correlated with the daily peak in irradiance. Nighttime nitrate maxima
reflected a pattern in which surface-layer stocks were depleted each afternoon and recharged the
following night. Changes in nitrate concentrations were used to generate daily estimates of new
primary production (182 ± 37 mg C m-2 d-1) and the f-ratio (0.25), i.e., the ratio of production
based on nitrate to total production. These estimates, the first of their kind in Long Island Sound,
were compared to values of community respiration, primary productivity, and net ecosystem
metabolism, which were derived from in situ measurements of oxygen concentration. Daily
averages of the three metabolic parameters were 1660 ± 431, 2080 ± 419, and 429 ± 203 mg C
m-2 d-1, respectively. While the system remained weakly autotrophic over the duration of the
study period, we observed very large day-to-day differences in the f-ratio and in the various
metabolic parameters.This work was supported by the Yale
Institute for Biospheric Studies, the Sounds Conservancy of the Quebec-Labrador Foundation,
and the Yale School of Forestry and Environmental Studies Carpenter-Sperry Fund.2014-01-0
Revisiting the Gaia Hypothesis: Maximum Entropy, Kauffman’s ‘Fourth Law’ and Physiosemeiosis
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