Chapter 1 The Biosphere Chapter 2 The Anthroposphere Introduction Air Pollution Water Pollution Soil Plants Chapter 3 Soils and Soil Processes Introduction Weathering Processes Pedogenic Processes Chapter 4 Soil Constituents Introduction Trace Elements Minerals Organic Matter Organisms in Soils Chapter 5 Trace Elements in Plants Introduction Absorption Translocation Availability Essentiality and Deficiency Toxicity and Tolerance Speciation Interaction Chapter 6 Elements of Group 1 (Previously Group Ia) Introduction Lithium Rubidium Cesium Chapter 7 Elements of Group 2 (Previously Group IIa) Beryllium Strontium Barium Radium Chapter 8 Elements of Group 3 (Previously Group IIIb) Scandium Yttrium Lanthanides Actinides Chapter 9 Elements of Group 4 (Previously Group IVb) Titanium Zirconium Hafnium Chapter 10 Elements of Group 5 (Previously Group Vb) Vanadium Niobium Tantalum Chapter 11 Elements of Group 6 (Previously Group VIb) Chromium Molybdenum Tungsten Chapter 12 Elements of Group 7 (Previously Group VIIb) Manganese Technetium Rhenium Chapter 13 Elements of Group 8 (Previously Part of Group VIII) Iron Ruthenium Osmium Chapter 14 Elements of Group 9 (Previously Part of Group VIII) Cobalt Rhodium Iridium Chapter 15 Elements of Group 10 (Previously Part of Group VIII) Nickel Palladium Platinum Chapter 16 Elements of Group 11 (Previously Group Ib) Copper Silver Gold Chapter 17 Trace Elements of Group 12 (Previously of Group IIb) Zinc Cadmium Mercury Chapter 18 Elements of Group 13 (Previously Group IIIa) Boron Aluminum Gallium Indium Thallium Chapter 19 Elements of Group I4 (Previously Group IVa) Silicon Germanium Tin Lead Chapter 20 Elements of Group 15 (Previously Group Va) Arsenic Antimony Bismuth Chapter 21 Elements of Group 16 (Previously Group VIa) Selenium Tellurium Polonium Chapter 22 Elements of Group 17 (Previously Group VIIa) Fluorine Chlorine Bromine Iodine

Trace elements in soils and plants

A model for the photochemistry of the global troposphere constrained by observed concentrations of H2O, O3, CO, CH4, NO, NO2, and HNO3 is presented. Data for NO and NO2 are insufficient to define the global distribution of these gases but are nonetheless useful in limiting several of the more uncertain parameters of the model. Concentrations of OH, HO2, H2O2, NO, NO2, NO3, N2O5, HNO2, HO2NO2, CH3O2, CH3OOH, CH2O, and CH3CCl3 are calculated as functions of altitude, latitude, and season. Results imply that the source for nitrogen oxides in the remote troposphere is geographically dispersed and surprisingly small, less than 107 tons N yr−1. Global sources for CO and CH4 are 1.5 × 109 tons C yr−1 and 4.5 × 108 tons C yr−1, respectively. Carbon monoxide is derived from combustion of fossil fuel (15%) and oxidation of atmospheric CH4 (25%), with the balance from burning of vegetation and oxidation of biospheric hydrocarbons. Production of CO in the northern hemisphere exceeds that in the southern hemisphere by about a factor of 2. Industrial and agricultural activities provide approximately half the global source of CO. Oxidation of CO and CH4 provides sources of tropospheric O3 similar in magnitude to loss by in situ photochemistry. Observations of CH3CCl3 could offer an important check of the tropospheric model and results shown here suggest that computed concentrations of OH should be reliable within a factor of 2. A more definitive test requires better definition of release rates for CH3CCl3 and improved measurements for its distribution in the atmosphere.

/pdf/tropospheric-chemistry-a-global-perspective-29u7u1il4s.pdf

Tropospheric chemistry: A global perspective

Sources, Effects and Risks of Ionizing Radiation

https://notendur.hi.is/oi/PDF%20reprints/Svendsen%20et%20al%20-%20Late%20Quaternary%20ice%20sheet%20history%20of%20northern%20Eurasia.pdf

Late quaternary ice sheet history of northern Eurasia

(1983). Ionizing Radiation: Sources and Biological Effects. International Journal of Radiation Biology and Related Studies in Physics, Chemistry and Medicine: Vol. 43, No. 5, pp. 585-586.

Ionizing Radiation: Sources and Biological Effects

Procedures developed for the sequential chemical separation and radiochemical analysis of 210Pb, 210Bi, 210Po, and 90Sr are described. Results from the measurements of these radioisotopes in surface air and precipitation are presented and discussed in relation to their sources and their application as tracers for the estimation of the residence times of particles in the lower atmosphere. It is concluded that the simple steady-state model does not apply to these long-lived radon daughters and that published residence time estimates based on 210Po/210Pb ratios are incorrect and too long. On the basis of 210Bi/210Pb activity ratios, correcting for the presence of an assumed secular equilibrium component of 210Pb, 210Bi, and 210Po, we estimate a mean atmospheric residence time of about 4 days for particles in the lower troposphere and about 1 week for particles in precipitation. Further tests of the steady-state assumption and other factors affecting such estimates are in progress.

Lead 210, bismuth 210, and polonium 210 in the atmosphere: Accurate ratio measurement and application to aerosol residence time determination

Results of measurements of 222Rn, 210Pb, 210Bi, 210Po, and 90Sr concentrations in air at various altitudes up to 16 km over the continental United States are presented and discussed in relation to their sources and application as tracers for the estimation of the residence time of particles in the troposphere and lower stratosphere. It is concluded from the ratios of these isotopes that the simple steady state model does not apply to the long-lived radon daughters. Comparison of mean radioisotope concentration profiles with a theoretical model indicates that the mean aerosol residence time in the troposphere is less than 7 days and that most of the 210Po in the troposphere is of continental surface origin. The magnitude of the increase in mean aerosol residence time with altitude within the troposphere appears to be less than a factor of 3. The mean aerosol residence time in the lower stratosphere is calculated to be about 1–2 months, approximately 10 times that of tropospheric aerosols.

222Rn, 210Pb, 210Bi, and 210Po profiles and aerosol residence times versus altitude

Mean tropospheric aerosol residence times determined from cosmic ray-produced isotope activity ratios, fallout, and /sup 210/Po//sup 210/Pb ratios are concluded to be in error. Thus, complementary sources of /sup 210/Po in the atmosphere must exist. Results presented substantiate dust storms, coal-burning power plants, forest fires, and plant exudates as sources of atmospheric /sup 210/Po. Preliminary estimates of the magnitude of these and other possible complementary sources of atmospheric /sup 210/Po are made. The most important sources appear to be soil particles and plant exudates, both of which are natural sources. The largest anthropogenic source is associated with phosphate fertilizer production. Together, the complementary sources account for most of the /sup 210/Po in the troposphere. Thus, a shorter residence time of 4-6 days appears reasonable.

Sources of polonium-210 in atmosphere

210Pb and 226Ra concentrations versus soil depth profiles are used to determine the 210Pb flux from the atmosphere to the earth's surface. A value of 1.6 dpm cm−2yr−1 is obtained. Other methods of obtaining the 210Pb flux are discussed. Values range from 0.53 to 2. 0 dpm Cm−2yr−1 for the north temperate zone. Estimates of continental values range from 0.8 to 2.0 dpm cm−2 yr−1 and oceanic values from 0.53 to 1.0 dpm cm−2 yr−1.

210Pb fluxes determined from 210Pb and 226Ra soil profiles

Concentrations Of 222Rn, 210Pb, 210Bi, 210Po, and 90Sr were determined in surface air on the windward side of Hawaii. About three fourths of the 222Rn on the lower slopes of the island is due to emanation from the island surface, whereas the remainder of the 222Rn and most of its long-lived radioactive daughters, 210Pb, 210Bi, and 210Po, are advected from distant continental sources. The transient time of air masses over the island, the transit time from distant continental regions, and the mean aerosol residence times above and below the trade wind inversion are estimated to be about 13 hours, 15–20 days, and 5 and 2 days, respectively.

H. E. Moore

Papers

Lead 210, bismuth 210, and polonium 210 in the atmosphere: Accurate ratio measurement and application to aerosol residence time determination

222Rn, 210Pb, 210Bi, and 210Po profiles and aerosol residence times versus altitude

Sources of polonium-210 in atmosphere

210Pb fluxes determined from 210Pb and 226Ra soil profiles

Origin of 222Rn and its long-lived daughters in air over Hawaii