Acidification of Forest Soils: A Model for Analyzing Impacts of Acidic Deposition in Europe - Version II

Acidification is an unfavorable process in forest soils. Timber logging, natural accumulation of biomass in the ecosystem, and acidic deposition are sources of acidification. Acidification causes a risk of damage to plant roots and a subsequent risk of a decline in ecosystem productivity. A dynamic model is introduced for describing the acidification of forest soils. In one-year time steps the model calculates the soil pH as function of acid stress and the buffer mechanisms of the soil. Acid stress is defined as the hydrogen ion input into the top soil. The buffer mechanisms counteract acidification by providing a sink for hydrogen ions. The concepts buffer rate and buffer capacity are used to quantify the buffer mechanisms. The model compares (i) the rate of the acid stress (annual amount) to the buffer rate, and (ii) the accumulated acid stress (over several years) to the buffer capacity. The comparisons produce an estimate of the soil acidity as the output. Since the first version in May 1984 several changes have been implemented following the advice of the experts. For aluminum and iron buffer ranges an equilibrium approach has been introduced. The pH of the silicate, cation exchange and upper aluminum buffer ranges is now a function of base saturation. In the current version of the model forests are assumed to absorb sulfur compounds more effectively than agricultural lands and, moreover, forests are assumed to grow on poor soil types rather than on the average soil type of a grid. The model system as a whole is now available for analyzing the impact of different emission scenarios. The soil acidification model assumes sulfur deposition estimates from the other submodels as input, and as output it computes the total area of forests in Europe with the estimated soil pH lower than any selected threshold value. Additionally it produces estimates of the acidity of European forest soils in a map format

Acidification of Forest Soils: Model Development and Application for Analyzing Impacts of Acidic Deposition in Europe

Acidification is considered as an unfavorable process in forest soils. Timber logging, natural accumulation of biomass in the ecosystem, and acidic deposition are known as sources of acidification. Acidification causes the risk of damage to plant roots and subsequent risk of a decline in ecosystem productivity. A dynamic model is introduced for describing the acidification of forest soils. In one-year time steps the model calculates the soil pH as function of the acid stress and the buffer mechanisms of the soil. Acid stress is defined as the hydrogen ion input into the top soil. The buffer mechanisms counteract acidification by providing a sink for hydrogen ions. The concepts 'buffer rate' and 'buffer capacity' are used to quantify the buffer mechanisms. The model compares (i) the rate of the acid stress (annual amount) to the buffer rate, and (ii) the accumulated acid stress (over several years) to the buffer capacity. These two types of comparisons produce an estimate of the soil pH as the output. The model was incorporated into a model system for analyzing the acidic deposition problem in Europe. The data on acid stress, entering the soils, was obtained from other submodels which link information on energy production, pollutant emission, pollutant transport, and pollutant deposition. Data on buffer rate and buffer capacity were collected from soil maps and geological maps. The model system as a whole is now available for analyzing different emission scenarios. The soil acidification model assumes sulfur deposition estimates from the other submodels as the input, and as the output it produces estimates of the pH of European forest soils in a map format. Additionally it computes the total area of forests in Europe with the estimated soil pH lower than any selected threshold value. Sources of uncertainty of the soil acidification model are listed and briefly evaluated

Acidification of Forest Soils

Acidification is considered to be an unfavourable process in forest soil. Timber logging, natural accumulation of biomass in the ecosystem, and acidic deposition are known sources of acidification. Acidification causes a risk of damage to plant roots and subsequent risk of a decline in ecosystem productivity. A dynamic model is introduced for describing the acidification of forest soils. In 1-year time steps the model calculates the soil pH as a function of the acid stress and the buffer mechanisms of the soil. Acid stress is defined as the hydrogen ion input into the top soil. The buffer mechanisms counteract acidification by providing a sink for hydrogen ions. The concepts "buffer rate" and "buffer capacity" are used to quantify the buffer mechanisms. The model compares (a) the rate of acid stress (annual amount) with the buffer rate, and (b) the accumulated acid stress (over several years) with the buffer capacity. These two comparisons give an estimate of the oil acidity. The model was incorporated into the Regional Acidification INformation and Simulation (RAINS) model system of IIASA for analyzing the acidic deposition problem in Europe. This system links information on energy production, pollutant emission, pollutant transport, and pollution deposition. The data on acid stress entering the soils was obtained from other submodels. Data on buffer rate and buffer capacity were collected from soil maps and geological maps. The model system as a whole is now available for analyzing the impact of different emission scenarios. The soil acidification model assumes sulfur deposition estimates from the other submodels as input, and as output it produces estimates of the acidity of European forest soils in a map format. Additionally it computes the total area of forests in Europe with the estimated soil pH lower than any selected threshold value. Sources of uncertainty in the soil acidification are listed and briefly evaluated

Comparison of phosphor screen autoradiography and micro-pattern gas detector based autoradiography for the porosity of altered rocks

This study aims to further develop the C-14-PMMA porosity calculation method with a novel autoradiography technique, the Micro-pattern gas detector autoradiography (MPGDA). In this study, the MPGDA is compared with phosphor screen autoradiography (SPA). A set of rock samples from Martinique Island exhibiting a large range of connected porosities was used to validate the MPGDA method. Calculated porosities were found to be in agreement with ones from the SPA and the triple-weight method (TW). The filmless nature of MPGDA as well as straightforward determination of C-14 radioactivity from the source rock makes the porosity calculation less uncertain. The real-time visualization of radioactivity from C-14 beta emissions by MPGDA is a noticeable improvement in comparison to SPA.Peer reviewe

Systemic inflammatory responses following welding inhalation challenge test

Peer reviewe

Integrated Analysis of Acidification in Europe.

This paper presents the interim status of the RAINS model developed at IIASA. The principle purpose of the model is to provide a tool to assist decision-makers in their evaluation of strategies to control acidification of Europe's environment. Model design emphasizes user comprehension and ease of use. The overall framework of RAINS consists of three linked compartments: "Pollutant Generation," "Atmospheric Processes" and "Environmental Impact." Each of these compartments can be filled by different substitutable submodels. The four submodels currently available are "Sulfur Emissions," EMEP Sulfur Transport," Forest Soil Acidity" and "Lake Acidity." Submodels which deal with NOx emissions and deposition and other environmental impacts will be added to the model. To operate the model, a user must select (1) an energy pathway, (2) a pollution control strategy and (3) an environmental impact indicator. This information is inputed to RAINS and yields a "scenario" which is a consistent set of energy pathway, sulfur emissions, forest soil acidity and lake acidity. In an iterative fashion, a model user can quickly evaluate the consequences of many different alternatives to control acidification in Europe

Effects of land management on large trees and carbon stocks

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Petrophysics of Chicxulub Impact Crater's Peak Ring

A new set of physical property measurements was undertaken on 29 peak-ring samples from the IODP-ICDP Expedition 364. Among the studied lithologies, the dominant one recovered in the peak ring consists of shocked granitoid rocks (19 samples). Porosity measurements with two independent methods (triple weight and C-14-PMMA porosity mapping) concur and bring new observations on the intensity and distribution of fracturing and porosity in these shocked target rocks. Characterization of the porous network is taken a step further with two other independent methods (electrical and permeability measurements). Electrical properties such as the cementation exponent (1.59 m < 1.87) and the formation factor (21 F < 103) do not compare with other granites from the published literature; they point at a type of porosity closer to clastic sedimentary rocks than to crystalline rocks. Permeabilities of the granitoid rocks range from 0.1 to 7.1 mD under an effective pressure of similar to 10 MPa. Unlike other fresh to deformed and altered granitoid rocks from the literature compared in this study, this permeability appears to be relatively insensitive to increasing stress (up to similar to 40 MPa), with implications for the nature of the porous network, again, behaving more like cemented clastic rocks than fractured crystalline rocks. Other analyzed lithologies include suevite and impact melt rocks. Relatively low permeability (10(-3) mD) measured in melt-rich facies suggest that, at the matrix scale, these lithologies cutting through more permeable peak-ring granitoid rocks may have been a barrier to fluid flow, with implications for hydrothermal systems.Peer reviewe

Somatic STAT3 mutations in Felty syndrome: an implication for a common pathogenesis with large granular lymphocyte leukemia

Felty syndrome is a rare disease defined by neutropenia, splenomegaly, and rheumatoid arthritis. Sometimes the differential diagnosis between Felty syndrome and large granular lymphocyte leukemia is problematic. Recently, somatic STAT3 and STAT5B mutations were discovered in 30-40% of patients with large granular lymphocyte leukemia. Herein, we aimed to study whether these mutations can also be detected in Felty syndrome, which would imply the existence of a common pathogenic mechanism between these two disease entities. We collected samples and clinical information from 14 Felty syndrome patients who were monitored at the rheumatology outpatient clinic for Felty syndrome. Somatic STAT3 mutations were discovered in 43% (6/14) of Felty syndrome patients with deep amplicon sequencing targeting all STAT3 exons. Mutations were located in the SH2 domain of STAT3, which is a known mutational hotspot. No STAT5B mutations were found. In blood smears, overrepresentation of large granular lymphocytes was observed, and in the majority of cases the CD8(+) T-cell receptor repertoire was skewed when analyzed by flow cytometry. In bone marrow biopsies, an increased amount of phospho-STAT3 positive cells was discovered. Plasma cytokine profiling showed that ten of the 92 assayed cytokines were elevated both in Felty syndrome and large granular lymphocyte leukemia, and three of these cytokines were also increased in patients with uncomplicated rheumatoid arthritis. In conclusion, somatic STAT3 mutations and STAT3 activation are as frequent in Felty syndrome as they are in large granular lymphocyte leukemia. Considering that the symptoms and treatment modalities are also similar, a unified reclassification of these two syndromes is warranted.Peer reviewe