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I. V. Yevdokimov A. A. Larionova M. Schmitt V. O. Lopes de Gerenyu M. Bahn 《Eurasian Soil Science》2010,43(12):1373-1381
The contributions of root and microbial respiration to the total emission of CO2 from the surface of gray forest and soddy-podzolic soils were compared under laboratory and field conditions for the purpose
of optimizing the field version of the substrate-induced respiration method. The magnification coefficients of respiration
upon the addition of saccharose (k
mic) were first determined under conditions maximally similar to the natural conditions. For this purpose, soil cleared from
roots was put into nylon nets with a mesh size of 40 μm to prevent the penetration of roots into the nets. The nets with soil
were left in the field for 7–10 days for the compaction of soil and the stabilization of microbial activity under natural
conditions. Then, the values of k
mic were determined in the root-free soil under field conditions or in the laboratory at the same temperature and water content.
The contribution of root respiration as determined by the laboratory version of the substrate-induced respiration method (7–36%)
was lower compared to two field versions of the method (27–60%). Root respiration varied in the range of 24–60% of the total
CO2 emission from the soil surface in meadow ecosystems and in the range of 7–56% in forest ecosystems depending on the method
and soil type. 相似文献
3.
A. A. Larionova A. K. Kvitkina I. V. Yevdokimov S. S. Bykhovets A. F. Stulin 《Eurasian Soil Science》2014,47(5):416-424
An hypothesis about the different temperature dependences of the decomposition of the labile and stable organic carbon pools has been tested using an agrochernozem sampled from an experimental plot of 42-year-old continuous corn in Voronezh oblast. The partitioning of the CO2 loss during the decomposition of the labile and stable soil organic matter (SOM) at 2, 12, and 22°C in a long-term incubation experiment was performed using the method of 13C natural abundance by C3–C4 transition. On the basis of the determined decomposition constants, the SOM pools have been arranged in an order according to their increasing stability: plant residues < new (C4) SOM < old (C3) SOM. The tested hypothesis has been found valid only for a limited temperature interval. The temperature coefficient Q 10 increases in the stability order from 1.2 to 4.3 in the interval of 12–22°C. At low temperatures (2–12°C), the values of Q 10 insignificantly vary among the SOM pools and lie in the range of 2.2–2.8. Along with the decomposition constants of the SOM, the new-to-old carbon ratio in the CO2 efflux from the soil and the magnitude of the negative priming effect for the old SOM caused by the input of new organic matter depend on the temperature. In the soil under continuous corn fertilized with NPK, the increased decomposition of C3 SOM is observed compared to the unfertilized control; the temperature dependences of the SOM decomposition are similar in both agrochernozem treatments. 相似文献
4.
A. A. Larionova B. N. Zolotareva I. V. Yevdokimov S. S. Bykhovets Ya. V. Kuzyakov F. Buegger 《Eurasian Soil Science》2011,44(6):628-640
The intensity of decomposition of the organic matter in the particle-size fractions from a agrogray soil sampled in a 5-year-long
field experiment on the decomposition of corn residues was determined in the course of incubation for a year. The corn residues
were placed into the soil in amounts equivalent to the amounts of plant litter in the agrocenosis and in the meadow ecosystem.
A combination of three methods—the particle-size fractionation, the method of 13C natural abundance by C3–C4 transition, and the method of incubation—made it possible to subdivide the soil organic matter
into the labile and stable pools. The labile pool reached 32% in the soil of the agrocenosis and 42% in the meadow soil. Owing
to the negative priming effect, the addition of C4 (young) carbon favored the stabilization of the C3 (old) carbon in the
soil. When the young carbon was absent, destabilization or intense decomposition of the old organic matter was observed. This
process was found even in the most stable fine silt and clay fractions. 相似文献
5.
A. A. Larionova A. M. Ermolaev V. I. Nikitishen V. O. Lopes de Gerenyu I. V. Evdokimov 《Eurasian Soil Science》2009,42(12):1364-1373
The effect of different land-use practices on the carbon budget in old arable gray forest soils of Russia was studied in field
experiments. A short-term (for 6–7 years) cessation of mineral fertilization had no negative effects on the carbon budget
in the agrocenoses studied. Only the combination of zero fertilization with the return to monoculture and the introduction
of black fallows created a negative budget of humus in the soil. The regrassing of the eroded arable soil for 24 years increased
the humus reserve in the 0- to 60-cm layer by a factor of 1.6–1.7. The average annual accumulation of carbon and nitrogen
after the restoration of the perennial vegetation was 106–128 g C/m2 and 11–16 g N/m2, respectively. 相似文献
6.
Separate determination of root respiration and rhizomicrobial respiration is one of the most interesting, important, and methodologically complicated problems in the study of the carbon budget in soils and the subdivision of the CO2 emission from soils into separate fluxes. In this review, we compare the main principles, the advantages and disadvantages, and the results obtained by the methods of component integration, substrate-induced respiration, respiratory capacity, girdling, isotope dilution, model rhizodeposition, modeling of the 14CO2 efflux dynamics, exudates elution, and the δ13C measurements of the microbial biomass and CO2. Summarizing the results of the determinations performed by these methods, we argue that about 40% of the rhizosphere CO2 efflux is due to root respiration and about 60% of this efflux is due to the respiration of microorganisms decomposing root exudates. 相似文献
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A. A. Larionova A. N. Maltseva V. O. Lopes de Gerenyu A. K. Kvitkina S. S. Bykhovets B. N. Zolotareva V. N. Kudeyarov 《Eurasian Soil Science》2017,50(4):422-431
The mineralization and humification of leaf litter collected in a mixed forest of the Prioksko-Terrasny Reserve depending on temperature (2, 12, and 22°C) and moisture (15, 30, 70, 100, and 150% of water holding capacity ( WHC)) has been studied in long-term incubation experiments. Mineralization is the most sensitive to temperature changes at the early stage of decomposition; the Q 10 value at the beginning of the experiment (1.5–2.7) is higher than at the later decomposition stages (0.3–1.3). Carbon losses usually exceed nitrogen losses during decomposition. Intensive nitrogen losses are observed only at the high temperature and moisture of litter (22°C and 100% WHC). Humification determined from the accumulation of humic substances in the end of incubation decreases from 34 to 9% with increasing moisture and temperature. The degree of humification CHA/CFA is maximum (1.14) at 12°C and 15% WHC; therefore, these temperature and moisture conditions are considered optimal for humification. Humification calculated from the limit value of litter mineralization is almost independent of temperature, but it significantly decreases from 70 to 3% with increasing moisture. A possible reason for the difference between the humification values measured by two methods is the conservation of a significant part of hemicelluloses, cellulose, and lignin during the transformation of litter and the formation of a complex of humic substances with plant residues, where HSs fulfill a protectoral role and decrease the decomposition rate of plant biopolymers. 相似文献
8.
A. M. Larionova 《Russian Agricultural Sciences》2010,36(2):148-150
It has been established that under conditions of the Astrakhan oblast, on brown semidesert soils with sprinkler irrigation,
an irrigation intensity of 1.2 mm/min and irrigation dose of 250—300 m(su3)/ha should not be exceeded. If irrigation exceeds
this dose it is necessary to take measures to increase the infiltration capacity of the soil and reduce the volume of surface
runoff. 相似文献
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A. A. Larionova D. V. Sapronov V. O. Lopez de Gerenyu L. G. Kuznetsova V. N. Kudeyarov 《Eurasian Soil Science》2006,39(10):1127-1135
The respiration activity of roots was studied in field experiments on gray forest and soddy-podzolic soils and under cropland and natural vegetation. It was shown that the contribution of roots to the CO2 emission from the soil surface depends significantly on the method of determination. The contributions of fine and coarse roots to the total root respiration were approximately similar in forest ecosystems. The use of the method of substrate-induced respiration made it possible to obtain the best estimates of the contributions of root respiration and respiration of microorganisms. The application of glucose in the form of a dry mixture with sand or talc instead of in the water-soluble form appeared to be the optimal procedure for determining the root respiration under field moisture conditions. 相似文献