Vol 16, No 2 (2025)
- Year: 2025
- Published: 10.07.2025
- Articles: 4
- URL: https://edgccjournal.org/EDGCC/issue/view/13648
Full Issue
Theoretical works
Comparison of two schemes of radiation transfer within the vegetation canopy based on measurements at the Mukhrino carbon polygon
Abstract
Models of radiation transfer within vegetation cover are an important component of the Earth system models, since solar radiation is the main source of energy on Earth and determines the thermal regime of the soil. It also significantly depends on the interception of the radiation by vegetation. The aim of this work is to evaluate the accuracy of a two-stream model of radiation transfer and a multiple reflection model that approximates radiation fluxes within vegetation cover using geometric series. Validation and comparison of the models were conducted using automatic observations recorded in a forest ecosystem at the Mukhrino carbon polygon. It is shown that the latter model is sensitive both to setting the proportion between atmospheric direct and diffuse radiation coming from the atmosphere and to refining the reflection and transmission parameters for leaves by dividing the spectrum into several parts. It is demonstrated that when setting the same optical parameters, the two-stream scheme has a higher degree of consistency with observations than the multiple reflection scheme.
58-68
Experimental works
Нydrochemical differentiation in bog ecosystems
Abstract
Oligotrophic bogs are presented by a combination of microlandscapes with varying water tables and vegetation. The variability of these features may influence the rate of plant residue decomposition and the efficiency of biogenic compounds accumulation. These processes affect the formation of the microlandscape hydrochemical system and the bog. This study examines the variability of hydrochemical features in the main microlandscapes of the Mukhrino oligotrophic bog, located in the middle taiga subzone of Western Siberia. The study aim was to identify the distinctive features of bog water composition. The measured properties included concentrations of cations (Na+, NH4+, K+, Mg2+, Ca2+) and anions (Cl–, SO42–, PO43–, NO3–) dissolved organic carbon (DOC) and its spectral characteristics (SUVA254) . The dominant ions in the water are Na+ и K+ and Cl⁻ and Cl– и SO42–. Relative to the total measured ion concentrations, the ecosystems form the following order of increasing compound concentration: ryam-hollow complex (RHC) – open bog – ridge-hollow-pool complex (RHPC) – ridge-hollow complex (RHC) – typical ryam. A hydrochemical feature of the RHK is high DOC concentrations with low ion content. The open bog ecosystems are characterized by a cation composition dominated by K+ and NH4+. The GHPC exhibit elevated SO42– in the anionic composition, whereas the RHC areas show higher Cl–. concentrations. However, the waters of both ecosystems demonstrate low dissolved organic carbon (DOC) concentrations (71.3 and 66.1 mg/L, respectively). The typical ryam stands out with the highest DOC (85,8 mg/L) and measured ion concentrations.
69-80
Dynamics of carbon stock in the stand of Pinetum andromedo-eriophoroso-sphagnum over 50 years under extensive drainage in the conditions of the subtaiga of European Russia (West Dvina Peatland-Forest Station)
Abstract
In 1972-1973, large-scale drainage of peat lands for the purposes of effective forestry was carried out on the territory of the West Dvina Peatland-Forest Station of the Institute of Forest Science of the Russian Academy of Sciences in the Tver Region [Biogeocenological ..., 1982]. Here, in the conditions of the subtaiga of European Russia, swamp forests, bog moss forest and swamps are common, formed on different types of peat − from eutrophic to oligotrophic.
In 1974, a permanent sample plot was laid in the Pinetum andromedo-eriophoroso-sphagnosum on the oligotrophic bog. Repeated surveys of this sample plot were conducted in 1983 and 2023. The sample plot (SP) has the number 5-74, has an area of 0.36 ha and a rectangular shape of 36×100 m2 (Fig. 1). The long side of the SP is located parallel to the drainage ditches 35 m from them. The distance between the ditches is 106 m. The depth of the peat is about 4 m. The drainage regime corresponding to the location of SP 5-74 in the middle of the 106-meter channel is considered extensive.
The peat soil was characterized by the constancy of the botanical composition of peat-forming agents up to 3.5 m and was represented by the upper magellanicum peat (Sphagnum magellanicum Brid.) with a degree of decomposition of 5-25%, deeper − sphagnum transition (Sph. girgensonii Russ.) with a decomposition rate of up to 30%. The carbon content in peat is 48-50%, the pH does not exceed 3.0, the ash content is 2-5%. High peat soil is characterized by a low volume mass (density): from 0.046 in the upper layers to 0.090 g/cm3 in the lower ones [Glukhova, 1990].
In 1974 SP 5-74 was laid in the Pinetum andromedo-eriophoroso-sphagnosum, which was characterized by Vb class of productivity and V class of age. In 1983, a more productive pine forest of the same V class of age was formed at this place, but still belonging to the Vb class of productivity: compare table 1 for 1983 M = 24.4 m3/ha, and for 1974 M =14.3 m3/ha. In 2023, the Pinetum ledoso-sphagnosum drained of the Va class of productivity and V class of age with M=50.0 m3/ha was already described at this site. The taxational characteristics of the stand by year and layer are given in table 1.
Extensive drainage of Pinetum andromedo-eriophoroso-sphagnosum with Vb productivity class showed that 10 years after drainage, a more productive pine forest was formed, and 50 years later – Pinetum ledoso-sphagnosum drained with Va productivity class. Based on the taxation data, the stock of stand was calculated for three years of observations (1974, 1983, 2023), which amounted to 14.3, 24.4 and 50.0 m3/ha, respectively. To convert stand stocks into carbon stocks in the phytomass of a stand (trunk, branches, foliage, roots), a conversion coefficient was used, which, in accordance with the methodological guidelines [On approval ..., 2022] turned out to be 0.314. The analysis of carbon stocks showed that it increased 1.7 times in 10 years, and 3.5 times in 50 years.
Regression analysis of these data showed a linear dependence of the carbon stock (C) on the age of extensive drainage (Adrain) over a 50-year period (Fig. 2):
C = 0.2322 × Adrain + 5.0116, t/ha,
where R2 = 0.99; p-value (F) = 0.064 for α = 0.05.
The coefficient of determination (R2) of the regression linear equation is high, but the equation is not reliable (p-value (F) > α). In the future, these data can be replenished by analyzing the increments of model trees or mathematical modeling.
Over the 50-year drainage period, the average annual increase in the stock of the stand was 0.71 m3/ha and the average annual increase in the carbon stock of the phytomass of the stand was 0.24 t/ha. An analysis of the literature on drained bog pine forests of the V-Vb bonitet showed that the stock of stands, depending on the age of drainage, may generally increase, less often decrease.
81-90
Chronicle
How can discussions and recommendations from the Blue Earth Project influence politicians and voters in democracies?
Abstract
The Blue Earth Project (BEP), an initiative led by the Network of Researchers on the Chemical Emergence of Life (NoRCEL) convenes global public forums to explore the guiding question: How can discussions and recommendations from the Blue Earth Project influence politicians and voters in democracies? As climate change, biodiversity loss, and ecological degradation intensify, the need for inclusive, ethically grounded scientific discourse has never been greater. This paper outlines the theoretical basis, public value, and democratic relevance of BEP, making the case for its role in supporting evidence-based, citizen-informed policymaking. By integrating perspectives from science, ethics, and public participation, BEP serves as a model for engaging democratic societies in shaping planetary futures.
91-94