نتایج جستجو برای: anthropogenic factor
تعداد نتایج: 867506 فیلتر نتایج به سال:
Objective: Metal concentrations in 53 soil samples of Shahr-e-Babak were determined. Methods: Assessment of enrichment factor and geo-accumulation index revealed higher degree of contamination of Cd, Pb, and Cu in soil samples. Moreover, results of metal fractionation study revealed high amount of Cd and Pb are associated in weakly bounds may lead to environmental risk of these metals. Result...
In contrast with Mobility Factor (MF) and Risk Assessment Code (RAC) indices, IR attributes a risk share to metal species bound to reducible and oxidizable phases which are totally neglected in both of the two above-mentioned indices. In other words, besides the absolutely mobile fractions, the potentially mobile ones are also regarded in risk evaluation process elaborated by IR. The different ...
A statistical synthesis of marine aerosol measurements from experiments in four different oceans is used to evaluate a global aerosol microphysics model (GLOMAP). We compare the model against observed size resolved particle concentrations, probability distributions, and the temporal persistence of different size particles. We attempt to explain the observed sub-micrometre size distributions in ...
The purpose of this study is to analyze the chemical composition of wet precipitation in samples collected at three stations in the Candiota region in the Brazilian state of Rio Grande do Sul (RS). Samples were collected in 2004. Variables analyzed in wet precipitation were pH, conductivity, and concentration of Cl-, NO3-, SO4(2-) F-, Na+, Ca2+, Mg2+, K+, NH4+, Cu, Zn, Fe, Mn, Pb, Ni, Cd, Co, a...
We document causes of death in free-ranging California Condors (Gymnogyps californianus) from the inception of the reintroduction program in 1992 through December 2009 to identify current and historic mortality factors that might interfere with establishment of self-sustaining populations in the wild. A total of 135 deaths occurred from October 1992 (the first post-release death) through Decemb...
Models of species' distributions are commonly used to inform landscape and conservation planning. In urban and semiurban landscapes, the distributions of species are determined by a combination of natural habitat and anthropogenic impacts. Understanding the spatial influence of these two processes is crucial for making spatially explicit decisions about conservation actions. We present a logist...
The conservation value of natural vegetation is degraded by proximity to anthropogenic land uses. Previous global assessments focused primarily on the amount of land protected or converted to anthropogenic uses, and on forest vegetation. Comparative assessments of extant vegetation in terms of proximity to anthropogenic land uses are needed to better inform conservation planning. We conducted a...
An approach is presented to study the functioning of a karstic massif and assess the adverse effects of the anthropogenic pressure by monitoring some water chemical and physical parameters of its main springs. The approach has been applied to the Sette Comuni Plateau (Veneto Region, Italy) hosting a well developed karstic system, whose aquifer presents high vulnerability and undergoes a relevan...
Efforts to understand the influence of historical global warming on individual extreme climate events have increased over the past decade. However, despite substantial progress, events that are unprecedented in the local observational record remain a persistent challenge. Leveraging observations and a large climate model ensemble, we quantify uncertainty in the influence of global warming on th...
Soil inventories of anthropogenic radionuclides were investigated in altitudinal transects in 2 French regions, Savoie and Montagne Noire. Rain was negligible in these 2 areas the days after the Chernobyl accident. Thus anthropogenic radionuclides are coming hypothetically only from Global Fallout following Atmospheric Nuclear Weapon Tests. This is confirmed by the isotopic signatures ((238)Pu/...
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