Forests play a crucial role in global carbon cycling by absorbing and storing significant amounts of atmospheric carbon dioxide. Although boreal forests contribute to approximately 45% of the total forest carbon sink, tree growth and soil carbon sequestration are constrained by nutrient availability. Here, we examine if long-term nutrient input enhances tree productivity and whether this leads to carbon storage or whether stimulated microbial decomposition of organic matter limits soil carbon accumulation. Over six decades, nitrogen, phosphorus, and calcium were supplied to a Pinus sylvestris-dominated boreal forest. We found that nitrogen fertilization alone or together with calcium and/or phosphorus increased tree biomass production by 50% and soil carbon sequestration by 65% compared to unfertilized plots. However, the nonlinear relationship observed between tree productivity and soil carbon stock across treatments suggests microbial regulation. When phosphorus was co-applied with nitrogen, it acidified the soil, increased fungal biomass, altered microbial community composition, and enhanced biopolymer degradation capabilities. While no evidence of competition between ectomycorrhizal and saprotrophic fungi has been observed, key functional groups with the potential to reduce carbon stocks were identified. In contrast, when nitrogen was added without phosphorus, it increased soil carbon sequestration because microbial activity was likely limited by phosphorus availability. In conclusion, the addition of nitrogen to boreal forests may contribute to global warming mitigation, but this effect is context dependent.

• Klíčová slova
• boreal forest ecosystem, fertilization, microbial community composition, microbial degradation, nutrient limitation, soil carbon storage, structural equation modeling, tree woody biomass,
• MeSH
• biomasa MeSH
• borovice lesní růst a vývoj   metabolismus   mikrobiologie   MeSH
• dusík * metabolismus   MeSH
• fosfor * metabolismus   MeSH
• lesy MeSH
• průmyslová hnojiva * analýza   MeSH
• půda * chemie   MeSH
• půdní mikrobiologie * MeSH
• sekvestrace uhlíku MeSH
• stromy růst a vývoj   metabolismus   MeSH
• tajga MeSH
• uhlík * metabolismus   MeSH
• vápník metabolismus   analýza   MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• dusík * MeSH
• fosfor * MeSH
• průmyslová hnojiva * MeSH
• půda * MeSH
• uhlík * MeSH
• vápník MeSH

Urban expansion is one of the main factors driving terrestrial carbon storage (TCS) changes. Accurate accounting of TCS and rigorous quantification of its changes caused by historical urban expansion may help us to better predict its changes in the future. This study focuses on the carbon impacts of urbanization in China where the share of the urban population has increased from 18% in 1978 to 59% in 2017 and the growing will continue in the coming decades. Our results show that China's TCS decreased at an accelerating pace over the past three decades with an average reduction of 0.72TgC/y in 1980-1990 and 8.72TgC/y in 2000-2010, mostly due to conversion from cropland and woodland to urban land. Through simulating urban expansion under four scenarios from 2010 to 2050, we found a potential increasing trend in land conversion from woodland to urban land. This conversion trend would result in carbon storage loss at an average rate of 9.31TgC/y ∼ 12.94TgC/y in 2010-2050. The increasing trend in both land conversion and carbon storage loss is especially visible in the population centers of the Yangtze River Delta and the Pearl River Delta. Considering that the indirect emission effects of urbanization, such as farmland displacement, population migration, and land degradation, may be much larger, the overall emission impact of forthcoming urban expansion in China would increase the uncertainty of the nation's carbon emissions and potentially undermine China's targets as committed in the Paris Climate Agreement.

• MeSH
• lidé MeSH
• podnebí MeSH
• řeky MeSH
• uhlík * MeSH
• urbanizace * MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Geografické názvy
• Čína MeSH
• Názvy látek
• uhlík * MeSH

The concept of rewilding, which focuses on managing ecosystem functions through self-regulation by restoring trophic interactions through introduced animal species with little human intervention, has gained increasing attention as a proactive and efficient approach to restoring ecosystems quickly and on a large scale. However, the science of rewilding has been criticized for being largely theory-based rather than evidence-based, with available data being geographically biased towards the Netherlands and Scandinavian countries, and a lack of objective data on rewilding effects on soil processes and C sequestration. In response to a call for data-driven experimental rewilding projects focused on national contexts, we collected unique data on the effects of large herbivore rewilding on soil properties from eight sites in the Czech Republic. These include sites with a wide range of edaphic characteristics that were grazed by Exmoor ponies, European bison, and back-bred Bos primigenius cattle (singly or in combination) for 2-6 years on areas ranging from ≈30 to ≈250 ha. Despite the relatively short duration of rewilding actions and considerable variability in the response rate of soil properties to grazing, our results indicate improved nutrient availability (evidenced by higher nitrification rate or higher soluble nitrogen concentration) and accelerated ecosystem metabolism (higher soil microbial biomass and dissolved carbon content). On longer-grazed pastures, rewilding contributed to soil carbon sequestration associated with increased water holding capacity and improved soil structure. However, other soil properties (reduced dissolved P concentration or total P content) showed signs of low P availability in the soils of the rewilding sites. Therefore, carcass retention should be considered where possible. Our data, although limited in number and geographic coverage, allow us to conclude that large ungulate rewilding has the potential to enhance soil carbon sequestration and related ecosystem services in rewilding areas. At the same time, we urge similar monitoring as an essential part of other rewilding projects, which will ultimately allow much more robust conclusions about the effects of this management on soils.

• Klíčová slova
• Ecosystem services, Large herbivores, Rewilding, Soil C sequestration, Soil fertility, Water retention capacity,
• MeSH
• biomasa MeSH
• býložravci MeSH
• ekosystém * MeSH
• koně MeSH
• lidé MeSH
• půda * chemie   MeSH
• skot MeSH
• uhlík MeSH
• zavlečené druhy MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• skot MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• půda * MeSH
• uhlík MeSH

Soils and forest soil in particular represent important pools of carbon (C). The amount of C stored in soil depends on the input of organic matter into the soil, but also on quality of the organic matter, which determines the proportion of organic matter that remains in the soil or that is released from the soil as CO2. Here, we present a quantitative review of common garden experiments in which various tree species were planted alongside each other. The main goals of the study were to determine whether: 1) the amount of sequestered C under broadleaf and coniferous trees could be affected by soil age and previous land use; 2) the C:N ratio of leaf litter is correlated with the amount of sequestered C; 3) the amount of sequestered C under broadleaf and coniferous trees could be affected by pH and clay content. We found that the effects of broadleaf and coniferous trees on soil organic carbon (SOC) sequestration differed with the stage of soil development. We used soils with different previous land uses as a representative of different stages of soil development. Forest soils and agricultural soils represent soils in later stages of soil development and post-mining soils represent soils in early stages of development. In forest soils, more SOC was stored under coniferous trees than under broadleaf trees. In post-mining soils the opposite trend was found, i.e., more SOC was stored under broadleaf than coniferous trees. In afforested agricultural soils, SOC sequestration did not differ between broadleaf and coniferous trees. SOC sequestration under broadleaf trees was highest in soils with high pH. SOC sequestration was negatively correlated with the litter C:N ratio in post-mining soils but not in other more mature soils. Similarly, SOC sequestration was negatively correlated with the litter C:N in alkaline soils and in soils with high clay content. These results suggest that dominant SOC sequestration mechanisms change with stage of soil development such that SOC storage is greater under broadleaf trees in immature soils but is greater under coniferous trees in mature soils.

• Klíčová slova
• Carbon sequestration, Common garden, Soil organic carbon, Tree species,
• MeSH
• cévnaté rostliny * MeSH
• lesy MeSH
• půda MeSH
• sekvestrace uhlíku MeSH
• stromy * MeSH
• uhlík MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH
• Názvy látek
• půda MeSH
• uhlík MeSH

With accelerating environmental change, understanding forest disturbance impacts on trade-offs between biodiversity and carbon dynamics is of high socio-economic importance. Most studies, however, have assessed immediate or short-term effects of disturbance, while long-term impacts remain poorly understood. Using a tree-ring-based approach, we analysed the effect of 250 years of disturbances on present-day biodiversity indicators and carbon dynamics in primary forests. Disturbance legacies spanning centuries shaped contemporary forest co-benefits and trade-offs, with contrasting, local-scale effects. Disturbances enhanced carbon sequestration, reaching maximum rates within a comparatively narrow post-disturbance window (up to 50 years). Concurrently, disturbance diminished aboveground carbon storage, which gradually returned to peak levels over centuries. Temporal patterns in biodiversity potential were bimodal; the first maximum coincided with the short-term post-disturbance carbon sequestration peak, and the second occurred during periods of maximum carbon storage in complex old-growth forest. Despite fluctuating local-scale trade-offs, forest biodiversity and carbon storage remained stable across the broader study region, and our data support a positive relationship between carbon stocks and biodiversity potential. These findings underscore the interdependencies of forest processes, and highlight the necessity of large-scale conservation programmes to effectively promote both biodiversity and long-term carbon storage, particularly given the accelerating global biodiversity and climate crises.

• Klíčová slova
• biodiversity conservation, carbon sequestration, carbon storage, climate change, historical disturbance, primary forest,
• MeSH
• biodiverzita MeSH
• klimatické změny * MeSH
• lesy MeSH
• sekvestrace uhlíku MeSH
• stromy MeSH
• uhlík * analýza   MeSH
• zachování přírodních zdrojů MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• uhlík * MeSH

Plant growth is affected by light availability, light capture, and the efficiency of light energy utilisation within the photosynthetic uptake processes. The radiation use efficiency (RUE) of four even-aged, fully stocked mature Norway spruce stands along a temperature, precipitation, and altitudinal gradient of the Czech Republic was investigated. A new straightforward, methodological approach involving an analysis of digital hemispherical photographs for RUE estimation was applied. The highest annual RUE value (0.72 g MJ-1) was observed in the stand characterised by the lowest mean annual air temperature, the highest annual amount of precipitation, located at the highest altitude, and with the lowest site index reflecting site fertility. From the viewpoint of global climate change mitigation, this stand fixed 4.14 Mg ha-1 and 13.93 Mg ha-1 of carbon units and CO2 molecules into above-ground biomass, respectively. The lowest RUE value (0.21 g MJ-1) within the studied growing season was found in the stand located at the lowest altitude representing the site with the highest mean air temperature and the lowest amount of precipitation where 1.27 Mg ha-1 and 4.28 Mg ha-1 of carbon units and CO2 molecules, respectively, were fixed. From the tested meteorological variables (mean air temperature, the monthly sums of temperature, precipitation, and air humidity), RUE was only significantly dependent on air temperature. Therefore, global warming can lead to diminishing RUE and carbon sequestration in Norway spruce stands, especially at low altitudes.

• Klíčová slova
• Above-ground biomass, Carbon sequestration, Hemispherical photography, Picea abies, Solar radiation,
• MeSH
• klimatické změny * MeSH
• smrk * MeSH
• stromy MeSH
• teplota MeSH
• transpirace rostlin MeSH
• uhlík MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Česká republika MeSH
• Norsko MeSH
• Názvy látek
• uhlík MeSH

Tin dioxides (SnO2) inserted into carbons to serve as anodes for rechargeable lithium-ion batteries are known to improve their cycling stability. However, studies on diverse-shaped SnO2 nanoparticles within a porous carbon matrix for super stable lithium-ion storage are rare. Herein, a hollow carbon sphere/porous carbon flake (HCS/PCF) framework is fabricated through template carbonization of plastic waste. By changing the doping mechanism and tuning the loading content, nano SnO2 spheres and cubes as well as bulk SnO2 flakes and blocks are in-situ grown within the HCS/PCF. Then, the as-prepared hybrids with built-in various morphological SnO2 nanoparticles serve as anodes towards advanced lithium-ion batteries. Notably, HCS/PCF embedded with nano SnO2 spheres and cubes anodes possess superb long-term cycling stability (~0.048% and ~0.05% average capacitance decay per cycle at 1 A/g over 400 cycles) with high reversible specific capacities of 0.45 and 0.498 Ah/g after 1000 cycles at 5 A/g. The ultra-stabilized Li+ storage is attributed to the effective mitigation of nano SnO2 spheres/cubes volume expansion, originating from the compact SnO2 yolk-HCS/PCF shell construction. This study paves a general strategy for disposing of polymeric waste to produce SnO2 core-carbon shell anodes for super stable lithium-ion storage.

• Klíčová slova
• Hollow carbon sphere, Plastic waste, Porous carbon flake, Tin oxide, lithium-ion battery,
• Publikační typ
• časopisecké články MeSH

The design of advanced high-energy-density supercapacitors requires the design of unique materials that combine hierarchical nanoporous structures with high surface area to facilitate ion transport and excellent electrolyte permeability. Here, shape-controlled 2D nanoporous carbon sheets (NPSs) with graphitic wall structure through the pyrolysis of metal-organic frameworks (MOFs) are developed. As a proof-of-concept application, the obtained NPSs are used as the electrode material for a supercapacitor. The carbon-sheet-based symmetric cell shows an ultrahigh Brunauer-Emmett-Teller (BET)-area-normalized capacitance of 21.4 µF cm-2 (233 F g-1 ), exceeding other carbon-based supercapacitors. The addition of potassium iodide as redox-active species in a sulfuric acid (supporting electrolyte) leads to the ground-breaking enhancement in the energy density up to 90 Wh kg-1 , which is higher than commercial aqueous rechargeable batteries, maintaining its superior power density. Thus, the new material provides a double profits strategy such as battery-level energy and capacitor-level power density.

• Klíčová slova
• 2D materials, graphitic nanoporous carbon sheets, metal-organic frameworks (MOFs), morphology control, supercapacitors,
• Publikační typ
• časopisecké články MeSH

Plants store nonstructural carbohydrates (NSCs) like starch, fructans and soluble sugars to support metabolism, stress tolerance and defence during low photosynthesis, ultimately influencing their growth and longevity. However, the relationship between NSC composition and growth or persistence in wild plants remains unclear. This study explores trade-offs between growth, longevity and NSCs in 201 plant species across diverse climates in the Western USA, spanning 500-4300 m in elevation and 80-1000 mm in precipitation. Annual growth rates and plant ages were derived from the ring widths of semidesert, steppe and alpine herbs and shrubs, along with NSC profiles in their roots and rhizomes. Results showed an inverse relationship between growth and age, with total NSC, starch and fructan levels negatively correlated with growth, supporting the growth-longevity and growth-storage trade-off hypotheses. Conversely, higher growth rates were linked to soluble sugars, suggesting that climate-driven growth limitations alone do not explain increased NSCs. Fructans were positively associated with longevity, especially in long-lived desert shrubs and alpine herbs, underscoring NSCs' active role in survival strategies. These findings challenge the carbon surplus hypothesis, suggesting that plants actively use specific NSCs to balance growth and persistence, with energy-rich sugars promoting growth and osmoprotective fructans enhancing longevity.

• Klíčová slova
• active accumulation, carbon allocation strategies, carbon allocation trade‐offs, longevity, nonstructural carbohydrates, plant growth,
• Publikační typ
• časopisecké články MeSH

In this article, some new approaches to characterize the carbon paste mixtures and the respective carbon paste electrodes (CPEs) are presented, discussed, and critically evaluated. Particular attention has been paid to the changes of the ohmic resistance, relative to the dependence on composition of the CPE, the materials used, the time, and the position of storage. Four types of carbon pastes were examined, and for the interpretation of experimental data, a new simple model of "close-packing of spheres" has been applied. This model resembles the percolation theory for solid matter. In our case, however, it is possible to explain not only the "bent" or "broken" shape of the dependence of the electrode resistance upon the binder:carbon ratio and the corresponding electrochemical current response, but also differences caused by various material used and three various effects observed during the electrode aging. Furthermore, the report presents the significance of practical utilization of the recently introduced carbon paste index (denoted as chi(CPE)), which is a qualitative hitherto unused factor based on the evaluation of cyclic voltammograms for standard redox systems (e.g., [Fe(CN)(6)](3-/4-)) and specifying the electrochemical properties of a CPE. Some problems connected with homogeneity and stability of carbon pastes, their handling, storage, or eventual aging effects are also discussed.

• MeSH
• elektrická impedance MeSH
• elektrochemie * MeSH
• elektrody * MeSH
• uhlík chemie   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• uhlík MeSH