The interaction between atmospheric deposition of mineral nitrogen and soil-vegetation indices in forests ecosystem of European Russia

Irina Averkieva1, Irina Grosovskaya2, Kristina Ivashenko3
1 Laboratory of Geochemistry and Mineralogy of soils, Institute of Physical-Chemical and Biological Problems in Soil Science Russian Academy of Sciences
2 Laborotory Ecological modeling
3 Laboratory soil carbon and nitrogen cycles

P 3.2 in Fluxes between the atmosphere and ecosystems

Poster Session 2 on Tuesday, 16:30-18:00

In the last three decades nitrogen compounds are priority pollutants of the atmosphere (industry, transport and agriculture intensification). It leads to increasing nitrogen in terrestrial ecosystems, changing biogeochemical nitrogen cycle and as a result is various ecological disturbances. The disturbance’s degree depends on the level of nitrogen deposition, plant, soil properties and climate. In forests ecosystem of temperate zone of Russia mineral soil nitrogen content is limiting factor for growth and plant nutrition. Our research is focused on the relationship between atmospheric deposition of mineral nitrogen content (Nmin) and soil chemical properties, as well as Nmin and plant composition. In deciduous and coniferous forests (40-60 yrs) in Kostroma and Moscow regions the soil (n=300) and snow (n=150) samples were taken, and plant types were described (n=150). Soddy-podzolic (Umbric Albeluvisols) soil is different texture, pHw is 4.3-5.8. It was found the atmospheric deposition of Nmin reached in average 13 and 4 kg N ha-1 yr-1 for Moscow and Kostroma regions, respectively. In soil of Moscow region the content of NH4, NO3 and C/N ratio were in average 4, 8 mg N kg-1, and 18, compared in Kostroma region it was 4, 2 mg N kg-1, and 28, respectively.

The significant relationship (p≤0.05) between the content of Nmin and soil Ntot, Nmin and soil C/N ratio was founded (R=0.58, 0.63, respectively).The relationship between Nmin and soil parameters (Ctot , pHw, Ca, Mg, K, Na, texture) was not revealed. Found that in areas with high Nmin (≥ 10 kg ha-1 yr-1) in soil dominated nitrate form of nitrogen and with low Nmin (≤5 kg ha-1 yr-1) was ammonium, with 5-10 kg Nmin ha-1 yr-1 the soil ratio NH4 / NO3 = 1. It was shown at high NO3 atmospheric deposition (≥ 60% of Nmin) among forest plant was dominated species preferring high soil NO3 (Rubus idaeus, Urtica dioica, Humulus lupulus). It was typical for Moscow region. At low NO3 atmospheric deposition (≤ 60%) it was dominated Vaccinium myrtillus, Luzula pilosa, Linnaea borealis (low soil nitrogen content), which is typical for Kostroma region.

Thus, ours study shows the following: 1) increasing atmospheric Nmin in European Russia leads to increasing soil NO3- and C/N ratio in forests ecosystem; 2) at high atmospheric NO3 deposition (≥60% Nmin) is dominat plants that prefer soil with a high nitrogen content.

This work was supported by RFBR grant № 14-04-00098.

Letzte Änderung 14.03.2014