К 125-летию Иовеля Григорьевича Кутателадзе (1887–1963)

Статья посвящена жизни и деятельности И. Г. Кутателадзе — основателя высшего фармацевтического образования и научной фармации в Грузии, выдающегося фармакохимика, основателя и директора Тбилисского научно-исследовательского института фармакохимии, который с 1964 г. носит его имя, председателя научного общества фармацевтов Грузии и академика АН Грузинской ССР. Впервые подробно исследуется одесский период его деятельности.The article is devoted to life and activity of I. G. Kutateladze, founder of higher pharmaceutical education and scientific pharmacy in Georgia, prominent pharmacochemist, founder and director of the Tbilisi Research Institute of Pharmacochemistry, which has had his name since 1964, chairman of scientific society of pharmacists of Georgia and academician of AS of Georgian SSR. The Odessa period of his activity has been studied in details for the first time

Differential effects of elevated <scp> <i>p</i> CO ₂ </scp> and warming on marine phytoplankton stoichiometry

Phytoplankton stand at the base of the marine food-web, and play a major role in global carbon cycling. Rising CO2 levels and temperatures are expected to enhance growth and alter carbon:nutrient stoichiometry of marine phytoplankton, with possible consequences for the functioning of marine food-webs and the oceanic carbon pump. To date, however, the consistency of phytoplankton stoichiometric responses remains unclear. We therefore performed a meta-analysis on data from experimental studies on stoichiometric responses of marine phytoplankton to elevated pCO2 and 3–5° warming under nutrient replete and limited conditions. Our results demonstrate that elevated pCO2 increased overall phytoplankton C:N (by 4%) and C:P (by 9%) molar ratios under nutrient replete conditions, as well as phytoplankton growth rates (by 6%). Nutrient limitation amplified the CO2 effect on C:N and C:P ratios, with increases to 27% and 17%, respectively. In contrast to elevated pCO2, warming did not consistently alter phytoplankton elemental composition. This could be attributed to species- and study-specific increases and decreases in stoichiometry in response to warming. While our observed moderate CO2-driven changes in stoichiometry are not likely to drive marked changes in food web functioning, they are in the same order of magnitude as current and projected estimations of oceanic carbon export. Therefore, our results may indicate a stoichiometric compensation mechanism for reduced oceanic carbon export due to declining primary production in the near future

Differential effects of elevated pCO2 and warming on marine phytoplankton stoichiometry

Phytoplankton stand at the base of the marine food-web, and play a major role in global carbon cycling. Rising CO2 levels and temperatures are expected to enhance growth and alter carbon:nutrient stoichiometry of marine phytoplankton, with possible consequences for the functioning of marine food-webs and the oceanic carbon pump. To date, however, the consistency of phytoplankton stoichiometric responses remains unclear. We therefore performed a meta-analysis on data from experimental studies on stoichiometric responses of marine phytoplankton to elevated pCO2 and 3–5° warming under nutrient replete and limited conditions. Our results demonstrate that elevated pCO2 increased overall phytoplankton C:N (by 4%) and C:P (by 9%) molar ratios under nutrient replete conditions, as well as phytoplankton growth rates (by 6%). Nutrient limitation amplified the CO2 effect on C:N and C:P ratios, with increases to 27% and 17%, respectively. In contrast to elevated pCO2, warming did not consistently alter phytoplankton elemental composition. This could be attributed to species- and study-specific increases and decreases in stoichiometry in response to warming. While our observed moderate CO2-driven changes in stoichiometry are not likely to drive marked changes in food web functioning, they are in the same order of magnitude as current and projected estimations of oceanic carbon export. Therefore, our results may indicate a stoichiometric compensation mechanism for reduced oceanic carbon export due to declining primary production in the near future

Microclimatological consequences for plant and microbial composition in Sphagnum-dominated peatlands

In three Scandinavian peatlands we studied to what extent plant and microbial community compositions are governed by local-scale microhabitat, with a special interest in the effect of aspect (i.e. exposition of slopes). Despite differences in solar irradiance between the south- and north-facing slopes, maximum temperature was elevated in the south-facing slopes at the most northern site only. Pore-water nutrient concentrations were not affected by aspect, yet dissolved organic carbon concentrations were higher in the south-facing microhabitats. This was likely caused by higher vascular plant biomass. Plant and microbial community composition clearly differed among sites. In all three sites, microhabitat (i.e. prevailing water-table depth) affected the plant and microbial community compositions. Aspect, however, did not affect community composition, even though microclimate significantly differed between the south- and the north-facing aspects at the northernmost site. Our results highlight the complex link between plant community composition, microbial community and environmental conditions, which deserves much more attention than currently in order to fully understand the effects of climate change on peatland ecosystem function.I

Termite sensitivity to temperature affects global wood decay rates.

Deadwood is a large global carbon store with its store size partially determined by biotic decay. Microbial wood decay rates are known to respond to changing temperature and precipitation. Termites are also important decomposers in the tropics but are less well studied. An understanding of their climate sensitivities is needed to estimate climate change effects on wood carbon pools. Using data from 133 sites spanning six continents, we found that termite wood discovery and consumption were highly sensitive to temperature (with decay increasing >6.8 times per 10°C increase in temperature)-even more so than microbes. Termite decay effects were greatest in tropical seasonal forests, tropical savannas, and subtropical deserts. With tropicalization (i.e., warming shifts to tropical climates), termite wood decay will likely increase as termites access more of Earth's surface

Reading tea leaves worldwide: decoupled drivers of initial litter decomposition mass‐loss rate and stabilization

The breakdown of plant material fuels soil functioning and biodiversity. Currently, process understanding of global decomposition patterns and the drivers of such patterns are hampered by the lack of coherent large‐scale datasets. We buried 36,000 individual litterbags (tea bags) worldwide and found an overall negative correlation between initial mass‐loss rates and stabilization factors of plant‐derived carbon, using the Tea Bag Index (TBI). The stabilization factor quantifies the degree to which easy‐to‐degrade components accumulate during early‐stage decomposition (e.g. by environmental limitations). However, agriculture and an interaction between moisture and temperature led to a decoupling between initial mass‐loss rates and stabilization, notably in colder locations. Using TBI improved mass‐loss estimates of natural litter compared to models that ignored stabilization. Ignoring the transformation of dead plant material to more recalcitrant substances during early‐stage decomposition, and the environmental control of this transformation, could overestimate carbon losses during early decomposition in carbon cycle models

The contrasting effects of nutrient enrichment on growth, biomass allocation and decomposition of plant tissue in coastal wetlands

Aims: Eutrophication of coastal waters can have consequences for the growth, function and soil processes of coastal wetlands. Our aims were to assess how nutrient enrichment affects growth, biomass allocation and decomposition of plant tissues of a common and widespread mangrove, Avicennia marina, and how eutrophication drives changes in below-ground carbon sequestration. Methods: We assessed this through the measurement of above- and belowground growth and decomposition rates of plants and plant tissue in unenriched or nutrient enriched treatments. Results: Nutrient enrichment increased biomass allocation above-ground compared to below-ground in seedlings but not in fully developed, mature trees where we observed the opposite pattern. Experiments to assess root decomposition found that 40–50% of biomass was lost within six months with little change between 12 and 18\ua0months, indicating a high potential for accumulation of organic matter over time. We estimate root-derived carbon sequestration rates of 53, 250 and 94\ua0g C m\ua0year for unenriched control, N and P enriched treatments, respectively. Conclusions: These results show coastal eutrophication can be beneficial and detrimental to ecosystem function of coastal plants. Eutrophication stimulates root growth in fully developed trees, increasing organic matter input to soils. Our data suggests that organic matter accumulation will increase in areas with high nutrient availability where root growth is increased and rates of decomposition are low

Stabilization versus decomposition in alpine ecosystems of the Northwestern Caucasus: The results of a tea bag burial experiment

Mountainous areas exhibit highly variable decomposition rates as a result of strong local differences in climate and vegetation type. This paper describes the effect of these factors on two major determinants of the local carbon cycle: litter decomposition and carbon stabilization. In order to adequately reflect local heterogeneity, we have sampled 12 typical plant communities of the Russian Caucasus. In order to minimize confounding effects and encourage comparative studies, we have adapted the widely used tea bag index (TBI) that is typically used in areas with low decomposition. By incubating standardized tea litter for a year, we investigated whether (1) initial litter decomposition rate (k) is negatively correlated with litter stabilization (S) and (2) whether k or S exhibit correlations with altitude and other environmental conditions. Our results show that S and k are not correlated. Altitude, pH, and water content significantly influenced the stabilization factor S, while soil-freezing had no influence. In contrast, none of these factors predicted the decomposition rate k. Based on our data, we argue that collection of decomposition rates alone, as is now common practice, is not sufficient to understand carbon input to soils and can potentially lead to misleading results. Our data on community-specific decomposition and stabilization rates further constrain estimates of litter accumulation in subalpine communities and the potential effects of climate change

Stabilization versus decomposition in alpine ecosystems of the Northwestern Caucasus : The results of a tea bag burial experiment

Mountainous areas exhibit highly variable decomposition rates as a result of strong local differences in climate and vegetation type. This paper describes the effect of these factors on two major determinants of the local carbon cycle: litter decomposition and carbon stabilization. In order to adequately reflect local heterogeneity, we have sampled 12 typical plant communities of the Russian Caucasus. In order to minimize confounding effects and encourage comparative studies, we have adapted the widely used tea bag index (TBI) that is typically used in areas with low decomposition. By incubating standardized tea litter for a year, we investigated whether (1) initial litter decomposition rate (k) is negatively correlated with litter stabilization (S) and (2) whether k or S exhibit correlations with altitude and other environmental conditions. Our results show that S and k are not correlated. Altitude, pH, and water content significantly influenced the stabilization factor S, while soil-freezing had no influence. In contrast, none of these factors predicted the decomposition rate k. Based on our data, we argue that collection of decomposition rates alone, as is now common practice, is not sufficient to understand carbon input to soils and can potentially lead to misleading results. Our data on community-specific decomposition and stabilization rates further constrain estimates of litter accumulation in subalpine communities and the potential effects of climate change