Rivers Orinoco

Curare is a generic term for various South American arrow poisons. Curare has been used for centuries by the Indians along the Amazon and Orinoco rivers for immobilizing and paralyzing wild animals used for food. Preparations of curare are derived from Strychnos species, which contain quaternary neuromuscular alkaloids like tubocurarine. Tubocurarine is a potent antagonist at the nicotinic acetylcholine receptor. 

Johnsson, M. J., Stallard, R. F., and Lundberg, N. (1991). Controls on the composition of fluvial sands from a tropical weathering environment Sands of the Orinoco River drainage basin, Venezuela and Colombia. Geol. Soc. Am. Bull. 103,1622-1647. 

Barrios E, Herrera R, Valles JL (1994) Tropical floodplain agroforestry systems in mid-Orinoco River basin, Venezuela. Agroforest Syst 28 143-157... 

Figure 18. Orinoco River tributary Li isotope data (Huh et al. 2001). Tie lines connect samples pairs of dissolved (open symbol) and suspended load (filled symbol) for tributaries draining the Andes (circle) and those draining cratonic area (triangle). Isotopic compositions of suspended loads were similar in both cases, but the dissolved loads of Andes drainages were uniformly isotopically heavier. This difference was attributed not to lithology in the headwaters, but to transport- versus reaction-limited weathering conditions.

Hoefs J, Sywall M (1997) Lithium isotope compositions of Quaternary and Tertiary biogene carbonates and a global lithium isotope balance. Geochim Cosmochim Acta 61 2679-2690 Hogan JF, Blum JD (2003) Boron and lithium isotopes as groundwater tracers a study at the Fresh Kills Landfill, Staten Island, New York, USA. Applied Geochem 18 615-627 Huh Y, Chan LH, Edmond JM (2001) Lithium isotopes as a probe of weathering processes Orinoco River. Earth Planet Sci Lett 194 189-199... 

The Venezuelan tar sands are located in a 50— 100-km belt extending east to west for >700 km, immediately north of the Orinoco River. The precise limits of the deposit are not well defined because exploration efforts in the past concentrated on light and medium cmde accumulations. 

Variation among Sampling Sites. Dissolved humic substance samples from seven end-member environments were isolated for study. Autochthonous inputs to DOM were expected to dominate in Big Soda Lake and in Island Lake, which is a groundwater-sustained eutrophic lake in the sandhills of western Nebraska. Allochthonous inputs to DOM from a swamp environment predominate in the Suwannee River. They also dominate in the Calcasieu River in western Louisiana, but the proportion of swampland is much lower there. The Temi River is a tropical blackwater tributary of the Orinoco River in Venezuela, where allochthonous inputs dominate. The entire Sagavanirktok River basin is located north of the tree line on the North Slope of Alaska a mixture of allochthonous and autochthonous inputs was expected for the various rivers and lakes in this basin. Lastly, Hidden Lake Creek, which is the outlet of Hidden Lake on the Kenai Peninsula of Alaska, was sampled to determine if nutrient inputs from decaying salmon were contributing to primary production and autochthonous inputs to DOM. 

Fulvic and humic acid from Temi River, blackwater tributary of Orinoco River, Venezuela 0.820 HOD—solvent peak interferes 0.250 0.250 1.00 47.7... 

Lewis, W. M., Jr. 1988. Primary production in the Orinoco River. Ecology 69 679-692. 

One kind of surface emulsion that is desirable is the Orinoco bitumen emulsion produced from in situ steam stimulation and recovery in the Orinoco River deposit in Venezuela. This emulsion is reformulated into Orimulsion , an O/W emulsion, containing about 30% fresh water and a stabilizing surfactant (typically about 0.1 percent each of monoethanolamine and an alcohol ethoxylate) [588,759,760], The O/W emulsion has a viscosity of about 450 mPa-s (30 °C, 100 s-1) compared with the original bitumen viscosity of about 10000 mPa-s [760,761], This emulsion can be used as an alternative fuel for power-generating plants. Being water-continuous the emulsion is easily handled and transported, but otherwise behaves similarly to fuel oil. 

Figure 8.12 Absorption spectra for DOM with increasing wavelength in CDOM samples collected from the Suromoni (SU) and Orinoco Rivers (Venezuela) in the Amazonian plains. (Modified from Battin, 1998.)...

Battin, T.J. (1998) Dissolved organic matter and its optical properties in blackwater tributary of the upper Orinoco River, Venezuela. Qrg. Geochem. 28, 561-569. 

Jones, R.D., and Amador, J.A. (1993) Methane and carbon monoxide production, oxidation and turnover times in the Caribbean Sea as influenced by the Orinoco river. J. Geophys. Res. 98, 2353-2359. 

In 1801, the German explorer and naturalist Baron Alexander von Humboldt (after whom the Pacific current is named), identified the yopo tree botanically. While collecting flora near the Orinoco River, he watched the Maypure Indians prepare cohoba snuff by breaking the pods, moistening them and allowing them to ferment. When the pods turned black, they were kneaded with cassava meal and lime from snails into small cakes, which were eventually powdered. Humboldt noted, "it is not to be believed that the... 

MoreU, J. M., and Corredor, J. E. (2001). Photomineralisation of fluorescent dissolved organic matter in the Orinoco River plume Estimation of ammonia release. J. Geophys. Res. 106(C8), 16807-16813. 

South America. Due to its importance in terms of water discharge and to generally high trace-element levels, the Amazon river system has been well documented for a number of elements, including their seasonal variations. In Table 1, we have reported different analyses of the Amazon River and its major tributaries to show their temporal variability at a given location. Results of ultrafiltration experiments for the Amazon and Orinoco rivers demonstrate that the concentration of a number of elements in waters depends on filtration pore size. Finally, data for... 

The dissolved concentrations of zinc in the Yangtze, Amazon, and Orinoco rivers have been shown to strongly decrease with pH, between 5 and 8.5 (Shiller and Boyle, 1985). This decrease is similar to that obtained in an experiment in which the pH of unfiltered Mississippi River water was adjusted to various pH values, and to isotherms of zinc adsorption on various natural and synthetic metal oxides surfaces (Figure 23). According to Shiller and Boyle (1985), alkaline rivers have less dissolved zinc because they are more suspended sediment-rich that acidic rivers. values between adsorbed (acid-leachable) zinc and dissolved zinc approach 10 for the Mississippi, which indicates that the Mississippi transports 10 times more adsorbed zinc than dissolved zinc. 

J.W. Moffett, O.C. Zafiriou (1993). The photochemical decomposition of hydrogen peroxide in surface waters of the Eastern Caribbean and Orinoco River. J. Geophys. Res., 98,2307-2313. 

C.A. Moore, C.T. Farmer, R.G. Zika (1993). Influence of the Orinoco River on hydrogen peroxide distribution and production in the Eastern Caribbean. J. Geo-phys. Res., 98,2289-2298. 

GUARANA SEEDS, Guaranae semen The plant Paullinia cupana Kunth, family Sapindaceae, grows along the Orinoco River in Venezuela and in the Amazonas region in Brazil, where cultivation is also found. 

Fig. 6-9 Ternary diagram showing proportions of dissolved Si(OH)4, carbonate alkalinity (HCOj + CO3"), and (Q + S04 ) in the Orinoco River and Amazon River basins. Charged species are in equivalents Si(OH)4 is in mole units. The curves in the larger figure are numbered in total cation concentration (mEq/L). Unlike previous figures, symbols represent the total cation concentration interval that includes the sample s concentration. The predominant symbol within each interval corresponds to samples whose concentrations plot within that interval. In the smaller figure, the patterned areas correspond to the predominant source of samples whose concentrations plot within the areas (A) streams that drain cratonic areas (B) streams that originate in mountain belts, but that drain large areas of cratons (C) streams that drain mountain belts with extensive black shales (D) streams that drain mountain belts with extensive carbonate rocks and evaporite deposits. Adapted from Stallard (1988) with the permission of Kluwer Academic Publishers.

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