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Eurasian Soil Science - Soil-biogeochemical aspects of the current state of arable land in the Russian Federation are discussed. Considerable transformation of Russian agriculture has led to... 相似文献
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Sushko Sofia Ananyeva Nadezhda Ivashchenko Kristina Vasenev Vyacheslav Kudeyarov Valeriy 《Journal of Soils and Sediments》2019,19(8):3217-3225
Journal of Soils and Sediments - Urbanization significantly changes the carbon balance of the terrestrial ecosystem, an important component of which is soil CO2 emission. One of the main sources of... 相似文献
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Determination of the C balance is of considerable importance when forecasting climate and environmental changes. Soil respiration
and biological productivity of ecosystems (net primary production; NPP) are the basic components of the terrestrial C cycle.
In this study, a previously made assessment of the annual CO2 flux from Russian soils was improved upon. CO2 emissions from Russian soils during the growing period were shown to represent, on average, 53–82% of the annual CO2 flux from Russian soils. The total annual CO2 flux from Russian soils was estimated at 4.50 Gt C (C source). The NPP of Russian ecosystems was estimated at 4.81 Gt C year–1 (C sink). Our calculations showed values of CO2 emissions and the C sink to be very close. This shows that, in general, terrestrial ecosystems are under steady state.
Received: 1 December 1997 相似文献
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The losses of nitrogen (NH4, NO3, Norg), phosphorus (Portho, Ppoly, Porg) and potassium (K+) from watershed areas of minor rivers, draining regions of different agricultural land use in the Oka Valley, U.S.S.R., were investigated. No N, P, and K pollution was shown in these watersheds, even though the rate of losses was found to be highly correlated with the amounts of mineral fertilizers and FYM applied. The losses were also determined by the natural soil fertility, erosion processes and soil texture under the similar level of fertilization. 相似文献
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M. KROSSH A VN J. O. BJORGUM J. KRANE E. STEINNES 《European Journal of Soil Science》1990,41(3):371-377
Eleven samples of terrestrial humus from different vegetational backgrounds were examined with solid-state 13C NMR using cross-polarization and magic-angle spinning (CP-MAS). In addition, all the samples were run with a dipolar dephasing pulse sequence for non-quarternary carbon suppression (NQS). The humus samples all appeared to contain small amounts of aromatic substances and larger amounts of aliphatic compounds. Most of the samples contained considerable amounts of hydroxyl groups and acetals, which originate mainly from carbohydrates. No correlations were found between vegetational background and chemical structure. 相似文献
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On the basis of the analysis of lands cape-agrogeochemical balance of N carried out in watersheds of four small rivers the input values were shown to be considerably higher than output values during the 10-yr period. This was due to an increase in mineral fertilizer application with no commensurate rise in the export of agricultural production from the regions. 相似文献
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Used in high concentration as a soil fumigant, CS2 was broadly similar to CHCl3 in its effects on metabolism in soil; the amount of N mineralised in 10 days increased roughly 10-fold. the O2 consumption almost tripled and the evolution of CO2 more than doubled. However, the effects of CS2 were consistently slightly less than those of CHCl3.Used at low concentration (10 μg.g?1 soil) on a soil rich in organic matter (2.93% organic C), CS2 stopped nitrification completely, almost without other effect on soil respiration and mineralisation of N. In contrast, when used on a poorer soil (1.07% organic C) even 10 μgCS2.g?1 soil was sufficient to cause a detectable increase in both respiration and mineralisation of N, in addition to stopping nitrification. 相似文献
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Nadezhda D. Ananyeva Simona Castaldi Ekaterina V. Stolnikova Valery N. Kudeyarov Riccardo Valentini 《Archives of Agronomy and Soil Science》2013,59(4):427-446
The selective inhibition technique by specific antibiotics (streptomycin, cycloheximide) applied to substrate-induced respiration (SIR) measurement was used to test the relative contribution of fungi to bacteria (F/B ratio) to the overall microflora-induced activity in soils of European Russia. Investigated soils covered a wide climatic transect and different ecosystem types including managed vs. natural ecosystems. Before direct comparison among sites, the antibiotic inhibition technique was optimized for soil characteristics. Once the optimal concentration was set, the combined effect of the two antibiotics resulted in average 60% inhibition of SIR. The analyzed sites (in total 47) including various biomes (tundra, middle taiga, southern taiga, subtaiga, dark coniferous forests outside the boreal region, steppe, mountain forests and arable sites), were characterized by a wide range of soil pHw (3.95–7.95), soil organic carbon (0.69–24.08%), soil microbial biomass carbon (149–5028 µg C g?1 soil) and soil basal respiration (0.24–8.28 µg CO2-C g?1 soil h?1). In all the analyzed sites, a predominance of fungal over bacteria activity was observed with F/B ratios always higher than one (4.9 on average). Natural sites were characterized by higher F/B ratios (on average 5.6) compared to agricultural ones (on average 3.5). 相似文献
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V. N. Kudeyarov 《Eurasian Soil Science》2018,51(6):599-612
Studies on the assessment of soil respiration and ecosystem CO2 sink in the territory of Russia are reviewed over the period since the adoption of the United Nations Framework Convention on Climate Change (Rio de Janeiro, 1992). The first estimates of total soil respiration in the entire territory of Russia, made in 1995 to 1998, amount to 3.1 and 4.3 Gt C per growing season and per year, respectively. On average, soil CO2 efflux over the cold season (November–March) accounts for 20–30% of annual efflux. The contribution of heterotrophic respiration (R H ) to the total soil respiration (R S ) may reach 30–70%, depending on ecosystem type. Despite differences in methods used to measure R H , the results obtained by different authors vary within a relatively narrow range, from 2.9 to 3.5 Gt C/year at an uncertainty level of about 20%. The soil cover of Russia (11.7% of the global land area) accounts for 6.3% of global soil CO2 efflux. The data on ecosystem CO2 sink are widely scattered among publications. Estimates of carbon balance differ depending on approaches and methods used to determine its individual components and the level of uncertainty in the results. However, most of them confirm the main conclusion: the territory of Russia with its forests is an absolute CO2 sink with a potential of 200 Mt C/year. This conclusion has been corroborated in the absolute majority of studies performed by Russian and international research teams. 相似文献