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    • Geosciences, Vol. 8, Pages 382: Geographies and Scientometrics of Research on Natural Hazards

      This contribution aims to reveal patterns of research on natural hazards worldwide, based on the analysis of the Clarivate Analytics Web of Science database. A set of 588,424 research items published between 1900 and 2017 is analyzed, covering different types of natural hazards. Two categories of natural hazards are distinguished in this study: (i) geological/geomorphic (earthquakes, slope movements, erosion, volcanic activity, and others); and (ii) climatic/hydro-meteorological (floods, storms, drought, hurricane, and others). General trends, the geographical focus, and the involvement and cooperation between individual countries are revealed, pointing out certain patterns (e.g., hotspots of research) and trends (e.g., changing publishing paradigm). Further, a global overview of research on natural hazards is confronted with disastrous events, fatalities, and losses of MunichRE and SwissRE global databases of natural disasters.

    • Geosciences, Vol. 8, Pages 381: Residents’ Perception and Assessment of Geomorphosites of the Alvão—Chaves Region

      This work focuses on the paradigms of a multidimensional and interdisciplinary evaluation of geomorphological heritage and its valorisation within a geosystemic reading of relations between a geomorphological and cultural landscape. This research aims to (i) select geomorphosites at different scales, which represent the regional geodiversity, according to an interdisciplinary approach; and (ii) better understand the perception of the local population concerning the different values of geomorphosites by applying a questionnaire that addresses the scientific, preservation, use, cultural, and educational dimensions. First, the authors selected the geomorphosites at a regional level by respecting the following criteria: (i) representativeness of the landform as a morphogenetic process; (ii) the witnessed periods of morpho-dynamics with potential to contribute to the reconstruction of paleoenvironmental conditions; (iii) the current morpho-dynamic nature; (iv) the importance to the shaping of the cultural landscape; and (v) the use value. Results showed that the major landforms are perceived as those with greater value by the local populations.

    • Geosciences, Vol. 8, Pages 380: Acid Neutralization by Mining Waste Dissolution under Conditions Relevant for Agricultural Applications

      The acidification of agricultural soils in high rainfall regions is usually countered by the application of finely ground calcite or dolomite. As this carbonate dissolves, soil pH is raised, but CO2 is released. Mining activities often produce large quantities of very fine silicate rock-derived powders that are commonly deposited in stockpiles. However, the dissolution of such powders can also result in an increase in pH, without any direct release of CO2. Of particular interest are those silicate powders that have a high reactivity and higher capacity for raising pH. In this contribution, we report experimental work addressing the dissolution of various silicate rock-derived powders that were produced during mining activities in Norway under conditions that were representative of weathering in agricultural soils. Three different powders—derived from Åheim dunite, Stjernøya nepheline syenite, or Tellnes ilmenite norite—were exposed to different acids at pH 4 in unstirred flow cells, and dissolution or leaching kinetics were determined from the changes in the fluid composition. Based on these kinetics, pH neutralization rates were determined for the individual powders and compared to expected values for carbonates. Based on this comparison, it is concluded that the application of silicate rock-derived powder dissolution to replace carbonate-based liming may not be feasible due to slower reaction rates, unless larger quantities of a finer particle size than normal are used. The application of larger volumes of slower-reacting silicates may have the additional benefit of reducing the required frequency of liming.

    • Geosciences, Vol. 8, Pages 379: Where, What, When, and Why Is Bottom Mapping Needed? An On-Line Application to Set Priorities Using Expert Opinion

      Globally, there is a lack of resources to survey the vast seafloor areas in need of basic mapping data. Consequently, smaller areas must be prioritized to address the most urgent needs. We developed a systematic, quantitative approach and on-line application to gather mapping suggestions from diverse stakeholders. Participants are each provided with 100 virtual coins to place throughout a region of interest to convey their mapping priorities. Inputs are standardized into a spatial framework using a grid and pull-down menus. These enabled participants to convey the types of mapping products that they need, the rationale used to justify their needs, and the locations that they prioritize for mapping. This system was implemented in a proposed National Marine Sanctuary encompassing 2784 km2 of Lake Michigan, Wisconsin. We demonstrate key analyses of the outputs, including coin counts, cell ranking, and multivariate cluster analysis for isolating high priority topics and locations. These techniques partition the priorities among the disciplines of the respondents, their selected justifications, and types of desired map products. The results enable respondents to identify potential collaborations to achieve common goals and more effectively invest limited mapping funds. The approach can be scaled to accommodate larger geographic areas and numbers of participants and is not limited to seafloor mapping.

    • Geosciences, Vol. 8, Pages 378: Simulations of Moisture Gradients in Wood Subjected to Changes in Relative Humidity and Temperature Due to Climate Change

      Climate change is a growing threat to cultural heritage buildings and objects. Objects housed in historic buildings are at risk because the indoor environments in these buildings are difficult to control and often influenced by the outdoor climate. Hygroscopic materials, such as wood, will gain and release moisture during changes in relative humidity and temperature. These changes cause swelling and shrinkage, which may result in permanent damage. To increase the knowledge of climate-induced damage to heritage objects, it is essential to monitor moisture transport in wood. Simulation models need to be developed and improved to predict the influence of climate change. In a previous work, relative humidity and temperature was monitored at different depths inside wooden samples subjected to fluctuating climate over time. In this article, two methods, the hygrothermal building simulation software WUFI® Pro and the Simplified model, were compared in relation to the measured data. The conclusion was that both methods can simulate moisture diffusion and transport in wooden object with a sufficient accuracy. Using the two methods for predicted climate change data show that the mean RH inside wood is rather constant, but the RH minimum and maximum vary with the predicted scenario and the type of building used for the simulation.

    • A review on the global soil datasets for earth system modeling

      A review on the global soil datasets for earth system modeling Yongjiu Dai, Wei Shangguan, Dagang Wang, Nan Wei, Qinchuan Xin, Hua Yuan, Shupeng Zhang, Shaofeng Liu, and Fapeng Yan SOIL Discuss., https//doi.org/10.5194/soil-2018-32,2018 Manuscript under review for SOIL (discussion: open, 0 comments) Global soil dataset is one of the most important uncertainty sources for Earth System Models (ESMs). Soil datasets are used for model calibration, validation and comparison. The popular soil datasets used in ESMs are often with limited accuracy. Updated and comprehensive soil information needs to be incorporated in ESMs. New generation soil datasets with abundant soil observations and environmental covariates are preferred. Uncertainty of soil data needs to be incorporated in ESMs.

    • Organic carbon content in arable soil – aeration matters

      Organic carbon content in arable soil – aeration matters Tino Colombi, Florian Walder, Lucie Büchi, Marlies Sommer, Kexing Liu, Johan Six, Marcel G. A. van der Heijden, Raphaël Charles, and Thomas Keller SOIL Discuss., https//doi.org/10.5194/soil-2018-35,2018 Manuscript under review for SOIL (discussion: open, 0 comments) The role of soil aeration for carbon sequestration in arable soils is only little explored, especially at the farm level. In the current study, which was conducted on 30 fields that belong to individual farms, we show that well aerated soil contains higher soil organic carbon content than soil that is poorly aerated. We therefore conclude that soil aeration needs to be accounted for when developing strategies for carbon sequestration in arable soils.

    • Challenges of soil carbon sequestration in the NENA region

      Challenges of soil carbon sequestration in the NENA region Talal Darwish, Thérèse Atallah, and Ali Fadel SOIL, 4, 225-235, https://doi.org/10.5194/soil-4-225-2018, 2018 This paper is part of the GSP-ITPS effort to produce a global SOC map and update information on C stocks using old and new soil information to assess the potential for enhanced C sequestration in dry land areas of the NENA region. We used the DSMW from FAO-UNESCO (2007), focusing on organic and inorganic content in 0.3 m of topsoil and 0.7 m of subsoil, to discuss the human factors affecting the accumulation of organic C and the fate of inorganic C.

    • Continental soil drivers of ammonium and nitrate in Australia

      Continental soil drivers of ammonium and nitrate in Australia Juhwan Lee, Gina M. Garland, and Raphael A. Viscarra Rossel SOIL, 4, 213-224, https://doi.org/10.5194/soil-4-213-2018, 2018 Soil nitrogen (N) is an essential element for plant growth, but its plant-available forms are subject to loss from the environment by leaching and gaseous emissions. Still, factors controlling soil mineral N concentrations at large spatial scales are not well understood. We determined and discussed primary soil controls over the concentrations of NH4+ and NO3− at the continental scale of Australia while considering specific dominant land use patterns on a regional basis.

    • Refining physical aspects of soil quality and soil health when exploring the effects of soil degradation and climate change on biomass production: an Italian case study

      Refining physical aspects of soil quality and soil health when exploring the effects of soil degradation and climate change on biomass production: an Italian case study Antonello Bonfante, Fabio Terribile, and Johan Bouma SOIL Discuss., https//doi.org/10.5194/soil-2018-30,2018 Manuscript under review for SOIL (discussion: open, 2 comments) This study is restriced to soil physical aspects of soil quality and – health with the objective to define procedures with worldwide rather than only regional applicability, reflecting modern developments in soil physical research and focusing on important questions regarding possible effects of soil degradation and climate change.