Труды сотрудников ИЛ им. В.Н. Сукачева СО РАН

[Text] / P. . Dijkstra [et al.] // Eur. J. Soil Sci. - 2006. - Vol. 57, Is. 4. - P468-475, DOI 10.1111/j.1365-2389.2006.00793.x. - Cited References: 36 . - 8. - ISSN 1351-0754РУБ Soil Science

Аннотация: The availability of C and N to the soil microbial biomass is an important determinant of the rates of soil N transformations. Here, we present evidence that changes in C and N availability affect the N-15 natural abundance of the microbial biomass relative to other soil N pools. We analysed the N-15 natural abundance signature of the chloroform-labile, extractable, NO3-, NH4+ and soil total N pools across a cattle manure gradient associated with a water reservoir in semiarid, high-desert grassland. High levels of C and N in soil total, extractable, NO3-, NH4+ and chloroform-labile fractions were found close to the reservoir. The delta N-15 value of chloroform-labile N was similar to that of extractable (organic + inorganic) N and NO3- at greater C availability close to the reservoir, but was N-15-enriched relative to these N-pools at lesser C availability farther away. Possible mechanisms for this variable N-15-enrichment include isotope fractionation during N assimilation and dissimilation, and changes in substrate use from a less to a more N-15-enriched substrate with decreasing C availability.

Полный текст,
WOS,
Scopus

Держатели документа:
No Arizona Univ, Dept Biol Sci, Flagstaff, AZ 86011 USA
RAS, Inst Forest SB, Krasnoyarsk 660036, Russia
No Arizona Univ, Colorado Plateau Stable Isotope Lab, Flagstaff, AZ 86011 USA
No Arizona Univ, Sch Forestry, Flagstaff, AZ 86011 USA
No Arizona Univ, Merriam Powell Ctr Environm Res, Flagstaff, AZ 86011 USA

Доп.точки доступа:
Dijkstra, P...; Menyailo, O.V.; Doucett, R.R.; Hart, S.C.; Schwartz, E...; Hungate, B.A.

/ V. I. Kharuk [et al.] // Reg. Envir. Chang. - 2017. - Vol. 17, Is. 3. - P803-812, DOI 10.1007/s10113-016-1073-5. - Cited References:44. - This study was supported by Russian Science Fund (RNF) (Grant No. 14-24-00112). K. J. Ranson's contribution was supported in part by the NASA's Terrestrial Ecology Program. . - ISSN 1436-3798. - ISSN 1436-378XРУБ Environmental Sciences + Environmental Studies

Аннотация: Increased dieback and mortality of ``dark needle conifer'' (DNC) stands (composed of fir (Abies sibirica), Siberian pine (Pinus sibirica) and spruce (Picea obovata)) were documented in Russia during recent decades. Here we analyzed spatial and temporal patterns of fir decline and mortality in the southern Siberian Mountains based on satellite, in situ and dendrochronological data. The studied stands are located within the boundary between DNC taiga to the north and forest-steppe to the south. Fir decline and mortality were observed to originate where topographic features contributed to maximal water-stress risk, i.e., steep (18 degrees - 25 degrees), convex, south-facing slopes with a shallow well-drained root zone. Fir regeneration survived droughts and increased stem radial growth, while upper canopy trees died. Tree ring width (TRW) growth negatively correlated with vapor pressure deficit (VPD), drought index and occurrence of late frosts, and positively with soil water content. Previous year growth conditions (i.e., drought index, VPD, soil water anomalies) have a high impact on current TRW (r = 0.60-0.74). Fir mortality was induced by increased water stress and severe droughts (as a primary factor) in synergy with bark-beetles and fungi attacks (as secondary factors). Dendrochronology data indicated that fir mortality is a periodic process. In a future climate with increased aridity and drought frequency, fir (and Siberian pine) may disappear from portions of its current range (primarily within the boundary with the foreststeppe) and is likely to be replaced by drought-tolerant species such as Pinus sylvestris and Larix sibirica.

WOS,
Смотреть статью

Держатели документа:
Sukachev Inst Forest, Krasnoyarsk, Russia.
Siberian Fed Univ, Krasnoyarsk, Russia.
Siberian State Aerosp Univ, Krasnoyarsk, Russia.
NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA.

Доп.точки доступа:
Kharuk, Viacheslav I.; Im, Sergei T.; Petrov, Ilya A.; Dvinskaya, Mariya L.; Fedotova, Elena V.; Ranson, Kenneth J.; Russian Science Fund (RNF) [14-24-00112]; NASA's Terrestrial Ecology Program