Geographical Institute

The El Niño-Southern Oscillation (ENSO) exhibits its weakest predictability during boreal spring, a phenomenon known as the Spring Predictability Barrier (SPB). The SPB arises from weak air-sea coupling that limits the growth and persistence of the ENSO signal. Improving springtime prediction therefore requires identifying oceanic regions most relevant for convection variability. Here, we introduce a Sea Surface Temperature Range Index (SRI), which quantifies the spatial extent of Sea surface temperatures favorable for convection. Using SRI, we show that regions exceeding 26 °C in the east-central Pacific and 28.5 °C in the eastern Atlantic during spring are critical for initiating persistent intense convection. The expansion of these convection-sensitive areas strengthens the Bjerknes feedback by modulating the Walker circulation, providing an effective predictor of ENSO evolution. We further develop a Long Short-Term Memory deep learning model incorporating SRI, which achieves higher predictive skill than the average of dynamical and statistical models, especially for multiyear La Niña events. These results underscore the central role of convection-sensitive oceanic regions in alleviating the SPB.

Recently, many literature reviews have focused on soil inorganic carbon (SIC) and concluded that SIC should be studied as much as soil organic carbon (SOC) to complete the soil C balance at global scale. However, as SIC has been rarely studied lately, analytical methods for measuring its carbon content and 13C in calcareous soils have not been refined. Similarly, the quantification of different SIC pools remained poorly assessed. This study aimed to illustrate the diversity of SOC and SIC pools in calcareous soils. A soil collection of 160 soil samples were selected from mostly agricultural lands in Canada, Hungary, France, Germany, Italy, and Tunisia to cover a large range of SOC and SIC contents. The carbonate composition was mainly in the form of calcite and, to a lesser extent, dolomite. The natural abundance in 13C of SOC and SIC showed a small range of values for SOC (-35 to -20 ‰, median: -27‰) signalling a predominance of C3-plants, and a large range of values for the SIC (-31 to +3 ‰; median -5 ‰), indicating a possible mixture of inorganic carbon from different sources (Hazera et al. 2025). Standard procedures to quantify SOC and SIC involving pretreatments to remove one of the C forms and/or calculations could lead to both analytical errors and substantial measurement errors (Jakab et al. submitted). Thermal analysis (i.e. Rock-Eval®, RE) has been adapted to estimate SOC and SIC contents on a non-pretreated soil sample without needing statistical post-hoc corrections (Hazera et al., 2023, in press). This RE method was applied to characterize more than 400 particle-size fractions of 65 calcareous soils i.e., particulate organic matters (POM, > 50 µm) and mineral associated organic matters (MaOM, 20-50, 0-20 and 0-2 µm). The variability of C distribution in the different fractions was more pronounced for SIC than SOC: the SOC was mainly contained in the

Glacial isostatic adjustment (GIA) profoundly influences postglacial tectonics, sea-level change, and geothermal systems; however, its role during the deglaciation of the Neoproterozoic Snowball Earth remains poorly constrained. Sheet-crack is one of the diagnostic structures in Marinoan (635 Ma) cap carbonates that overlie glacial tillites. Available geochemical evidence indicates that sheet-crack cements precipitated immediately following crack formation, potentially preserving GIA-driven fluid signatures. This study presents fluid inclusion microthermometric data from sheet-crack quartz and barite cements along shelf-to-slope transects on the Yangtze Block, South China. Fluid inclusion homogenization temperatures (Th) reveal the occurrence of a ubiquitous low-temperature hydrothermal event, with most Th values clustering at ∼145 °C–190 °C and ∼120 °C–180 °C in platform facies and slope facies, respectively. Fluid salinities in platform facies exhibit unimodal distributions and low to moderate (∼2–8 wt % NaCl eq.), while those in slope facies show broadly continuous distributions, with most values concentrated at intermediate-to-high salinities (∼6–15 wt % NaCl eq.) and a subordinate low-salinity tail. These patterns are consistent with varying contributions from recirculated, geothermally heated seawater and basinal brines. We propose a refined model in which GIA-related geothermal anomalies promoted a widespread low-temperature hydrothermal circulation event, responsible for sheet-crack cementation shortly after the Marinoan deglaciation, South China.

Constructing ecological networks (ENs) is an effective measure to mitigate the conflict between urban development and ecological conservation. However, existing simulating methods lack adequate consideration of human ecological demands and the spatial scale differences between these demands and natural ecological processes. This might lead to issues such as incomplete ecological process cycles or structural mismatches being overlooked during ENs simulations. To address these gaps, this study proposed an urban multi-scale nested ENs simulating framework that integrates human ecological demands with natural ecological processes. The framework first simulated an ENs focused on natural ecological process cycles at a global scale (GS). Then, it simulated an ENs centered on human ecological needs within the core urban areas at local scale (LS). Finally, it nested these multi-scale ENs by using cross-scale ecological supply sources as connecting points. This framework was applied to simulate spatio-temporal pattern changes in ENs of Jinan City, a core city in downstream of the Yellow River in China, aiming to mitigate cross-scale ecological conflicts between human–nature interactions under the background of urbanization. The study’s findings revealed that the area of demand sources increased by 8.56 times over 20 years. the area of cross-scale supply sources decreased by 15 km2 relative to 2000, and the deterioration in connectivity was more pronounced in GS compared to LS, with a decline of approximately 13.8%. These changes indicate the presence of incomplete ecological process cycles and structural mismatches across the multi-scale boundaries within the study area, which have been worsening annually. We recommend optimizing Jinan City’s multi-scale ecological network through three key strategies: rectifying internal structural mismatches, protecting core ecological areas, and aligning regional ecological demands. Implementing these strategies could significantly improve the network structure, reduce cross-scale mismatches, and enhance ecological connectivity by about 9%. This study highlights the importance of addressing structural mismatches and promoting complete ecological cycles in urban multi-scale ENs simulating, providing valuable insights for formulating urban multi-scale ecological conservation and restoration policies.

The pedodiversity concept integrates diversity indices and GIS techniques to assess the spatial heterogeneity of soils. This study proposes using pedodiversity indices for Romania’s geographic regions and relief units to evaluate their connectivity. Keeping the map scale, the soil type-subtypes vector was simplified to soil types. Aggregation reduced the number of polygons from two taxonomic categories only for certain taxa (variable taxa), while constant taxa remained unchanged. Low connectivity in parts of the Southern and Eastern Carpathians and the Western Plain suggests the presence of numerous subtypes within soil assemblages, whereas arid regions (e.g., Dobrogea Plateau), characterized by lower taxonomic variability, display strong connectivity. The connectivity index ranks landform units as follows: plains < plateaus < Carpathians < Subcarpathians, differing from the geographic regions hierarchy. Among the indicators tested, the connectivity index exerts the strongest influence on spatial ranking, while the diversity index proves less decisive.

Geographical names are an important part of the cultural heritage of every nation. They are a fundamental building block of all civilisations or cultures, filling space with meaning and developing spatial identities. Geographical names in languages with few speakers, such as Slovenian, are often endangered, but this is even truer of the geographical names of ethnic minorities, including the Slovenians of Hungary, the smallest cross-border Slovenian minority. The far western edge of Hungary, which lies between Slovenia and Austria, is called the Rába Valley. It includes seven settlements in which bilingualism is officially present. An outward sign of this bilingualism is bilingual road signs with the names of settlements. The main subject of this research was microtoponyms. One of the results of the research is a map with a glossary based on extensive fieldwork and a review of archival sources. It is primarily intended for the general public. It is hoped that it will help preserve these microtoponyms in people’s memories and at the same time promote their everyday use in communication.