Changes in c : n : р ratios in plant biomass, soil and soil microbial biomass due to the warming and dessication effect of flaring

Climate warming results in significant changes in the structure and functioning of terrestrial ecosystems. The ecosystems situated near oil-well gas flares may be used as model ones for studying warming effect on soil and vegetation. By contrast to regular manipulation experiments where ecopysiological factors are modified or controlled artificially, we used anthropogenically affected conditions caused by the gas flaring. Our research was aimed to assess the warming and desiccation effect on the stoichiometric ratios of the principle nutrients (C : N : P) in pine phytomass, soil and soil microbial biomass. Soil organic matter (SOM) and dying microbial biomass were found to be exposed to the increased rate of mineralization under conditions of the abiotic stress. In addition, the decrease of relative С content in sustainable SOM pools occured along with the increase of C content in the most labile water-soluble pools. The significant decrease in C : N : P ratio in pine needles nearby the flare served as an additional factor for the increasing rate of SOM mineralization detected by lower C : N : P ratio in soil and soil microbial biomass. Thus, studying changes in stoichiometric ratios of biophylic elements as affected by abiotic factors seems to be prospective and promising methodological approach for predicting terrestrial ecosystem transformations under global climate changes.