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61.
S. V. Mamikhin V. N. Golosov T. A. Paramonova E. N. Shamshurina M. M. Ivanov 《Eurasian Soil Science》2016,49(12):1432-1442
Profiles of vertical 137Cs distribution in alluvial meadow soils on the low and medium levels of the Lokna River floodplain (central part of the Plavsk radioactive spot in Tula oblast) 28 years after the Chernobyl fallout have been studied. A significant increase in the 137Cs pool is revealed on the low floodplain areas compared to the soils of interfluves due to the accumulation of alluvium, which hampers the reduction of the total radionuclide pool in alluvial soils because of radioactive decay. The rate of alluvium accumulation in the soil on the medium floodplain level is lower by three times on average. An imitation prognostic model has been developed, which considers the flooding and climatic conditions in the region under study. Numerical experiments have quantitatively confirmed the deciding role of low-mobile forms in the migration of maximum 137Cs content along the soil profile in the absence of manifested erosion–accumulation processes. 相似文献
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D. A. Ivanov V. A. Tyulin N. V. Grits I. V. Gromtseva 《Russian Agricultural Sciences》2010,36(3):180-183
The spatiotemporal dynamics of productivity and botanical composition of herbaceous grass-legume stands within an agrolandscape
of a moraine hill are studied. The characteristics of the change in the energy value of the fodder being produced are revealed.
Recommendations on adapting meadow fodder production to the landscape conditions are given. 相似文献
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Kholodov V. A. Yaroslavtseva N. V. Farkhodov Yu. R. Yashin M. A. Lazarev V. I. Iliyn B. S. Philippova O. I. Volikov A. B. Ivanov A. L. 《Eurasian Soil Science》2020,53(6):739-748
Eurasian Soil Science - The extractable fractions of organic matter (OM) differing in their mobility—water-extractable organic matter, labile humic substances, and humic substances—have... 相似文献
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Slendy Rodríguez-Alarcón Nelly Rodríguez-Eraso Ivanov Pineda-Rincón René López-Camacho 《Landscape Ecology》2018,33(11):1851-1864
Context
Forest fragmentation alters the composition, structure and function of ecosystems and affects ecological processes that are fundamental for the provision of ecosystem services where functional diversity is sensitive to its effects. Analyzing the functional responses of the plant community to fragmentation can provide new approaches to its conservation and management.Objectives
We analyzed whether the functional diversity of woody individuals associated with aboveground biomass (AGB) in a high Andean forest in Colombia is affected by fragmentation.Methods
Based on three fragmentation categories identified using landscape metrics, we selected ten forest fragments. Multitrait and monotrait functional diversity indexes (foliar and wood) weighted by aboveground biomass were calculated in plots of 0.1 ha in each fragment. Analysis of variance was performed, and simple linear regressions were quantified to identify the relationships between functional diversity and fragmentation.Results
The category of large fragments had a higher average AGB than did the medium and small fragments. Fragmentation had effects on the variance of some foliar and stem traits but not on functional dominance. For the multitraits indexes, the edge contrast was negatively related with functional dispersion.Conclusions
The categories analyzed have similar responses in terms of functionality associated with AGB. We highlight the importance of small fragments in the maintenance of plant functional diversity and as reservoirs of AGB. We underline that small fragments are important to consider in the development of conservation and connectivity strategies.70.
Based on a specially developed model and Russia’s national soil geographical database, the quality of soils for agricultural exploitation is evaluated. All the country’s soils are ranked according to their properties and response to economic activities. Quality categories of soil for use in the agricultural industry are proposed. According to this assessment, approximately 76% of soils in Russia (without considering their current use) are not favorable for agricultural exploitation. 相似文献