Anthropogenic character

The backtrajectories highlight the basic sources of the aerosol pollution of the air masses, which can be assigned to two categories one of natural and the other of anthropogenic character. 

California is the most populated and the most extensively anthropogenically modified area of the USA. Moreover, this is a very complicated natural biogeochemical structure with numerous biogeochemical provinces charactered by different organization of food webs. A typical example is the selenium biogeochemical province in the Joaquin River valley where the exposure pathways have changed dramatically during the last century. 

The condition or state of a natural water body can be characterized by a set of measurable physical, chemical, and biological parameters and a description of observed phenomena. The condition results from the various inputs of diffuse and point sources from natural and anthropogenic origins. These inputs may be transformed from the place of input to the place of measurement depending on the character of the catchment and parameter. Water quality always reflects... 

The chemical data presented clearly show the special character of alpine running waters compared to those in the midland and lowlands. The high water flow in these systems and the low anthropogenic activities produce only a small impact from pollution of nutrients and results mostly in their good chemical status. This... 

The isotopic compositions of the industrial sulfur sources are generally so variable, that the assessment of anthropogenic contributions to the atmosphere is extremely difficult. Krouse and Case (1983) were able to give semiquantitative estimates for a unique situation in Alberta where the industrial SO2 had a constant value near 20%c. Generally, situations are much more complicated which limits the fingerprint character of the sulfur isotope composition of atmospheric sulfur to such rare cases. 

Volcanic eruptions cause changes in RF from 0.2 Wm 2 to 0.5 W m 2 (these values, however, are very conditional). To analyze the possible anthropogenic impacts on global climate, estimates of the sensitivity of the climate system to external forcings are very important. Hansen et al. (1998) assumed that a change in global mean SAT with a doubled C02 concentration should constitute 3 1°C. The unreliable character of RF estimates makes it worthwhile to use different scenarios of RF changes. Developments in this field can be exemplified by the work of Tett et al. (1999). 

The positive effect of the interaction between these factors was enhanced owing to the shallow-water character of the sea and its geographical position. Since the middle of the last century the environmental state of the Sea of Azov has been under great anthropogenic pressure, resulting in negative changes in the sea biota. 

The composition and concentration of the atmospheric aerosol for each localization in space and time can be represented as a superposition of some background and disturbing aerosols. The parameters of the latter depend on the character, power, and distance of one source or several sources of disturbance , and on the effectiveness of the mechanisms of sink. The regions of aerosol-generating mechanisms, both natural and anthropogenic, can serve as sources of disturbance. 

Many anthropogenic organic compounds are highly hydrophobic in character, that is, they possess high values of the 1-octanol/water partitioning coefficient (generally expressed as the log P). They can be present in different types of wastewaters. In such context, the two-phase partitioning bioreactors can be used for the elimination of these compounds from wastewater. They... 

Anthropogenic soils are formed by the recultivation of exploited earth minerals or devastated soils. Their characteristics depend on properties and characters of substrates and on the recultivation method [1-3]. 

In order to show the. .natural" character of the anthropogenic influence on the biosphere, Vernadsky examines technological activity as a black box . He takes in account only the chemical compounds and the velocity of the biogenic migration of chemical elements. 

Thus, natural sources often have a distinctly different character than anthropogenic sources, which are comparably constant with respect to seasonality. In addition, the source strength as well as the spatial distribution of natural sources may differ substantially from year to year. An extreme example is voleanic emission. 

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