Several peaks have been determined in the seasonal dynamics of the aboveground biomass of the yellow water lily. The aboveground biomass reaches its maximal values during the period of mass floweringearly fruiting. The accumulation of plant litter during the growing season occurs unevenly; its maximal values are reached when one type of leaves is replaced by the other. The net aboveground annual production of yellow water lily exceeds on average two times the maximum values of aboveground biomass. It is estimated that 1 m2 of overgrowths yields on average 349 g of organic carbon.

Представлены результаты многолетних исследований полужесткокрылых надсемейства Pentatomoidea (Heteroptera) на Северо-Востоке европейской части России. Выявлено 32 вида клопов из 24 родов, восьми подсемейств и пяти семейств: Pentatomidae (21 вид), Acanthosomatidae (6), Cydnidae (2), Scutelleridae (2), Thyreocoridae (1). При продвижении на север разнообразие щитников снижается: в южной тайге отмечен 21 вид, в средней – 28, в северной – 9 и крайнесеверной тайге – 5 видов. Выявлен лесной и луговой комплекс видов с соответствующим ярусным распределением. Региональная фауна щитников характерна для бореального пояса умеренной зоны и образована, в большинстве своем, транспалеарктическими (28 %), западно-центральнопалеарктическими (25 %), трансевразиатскими (22 %) видами, в широтном отношении превалируют виды с температно-субтропическим распространением (75 %). Составлен аннотированный список, обобщающий сведения о нахождении видов в регионе, их зонально-ландшафтном распределении, экологии и общем распространении.

Freshwater macrophytes shape not only the morphological “architecture” of shallow-water ecosystems but also their chemical milieu via low-molecular-weight organic compounds (LMWOCs) that may regulate phytoplankton, periphyton, and the microbiome within the leaf/shoot diffusive boundary layer and the surrounding water column. In this study, GC–MS (gas chromatography–mass spectrometry) was used to identify major LMWOCs of the low-molecular-weight metabolome (LMWM) in 11 widely distributed macrophyte species (Myriophyllum spicatum L., Sparganium emersum Rehm., Sparganium gramineum Georgi, the hybrid Sparganium × foliosum A. A. Bobrov, Volkova, Mochalova et Chemeris, Persicaria amphibia (L.) Delarbre, Potamogeton perfoliatus L., Nuphar lutea (L.) Sibth. & Sm., Potamogeton pectinatus L., Potamogeton natans L., Lobelia dortmanna L., and Ceratophyllum demersum L.). Compounds contributing more than 1% to the total LMWOCs pool were considered major, increasing the ecological realism of interpretations by focusing on metabolites more likely to reach effective concentrations in the plant microenvironment. For interspecific comparisons, the maximum recorded values of relative abundance and concentrations were used to estimate species “potential”. In total, 137 major LMWOCs were detected (four remained unidentified), and their numbers varied markedly among taxa (from 11 in N. lutea to 71 in P. perfoliatus). Similarity analyses (Jaccard, Sørensen–Czekanowski, Morisita–Horn) indicated that similarity based on compound lists and similarity based on dominance structure may diverge, reflecting differences between the “LMWOCs set” and the quantitative architecture of LMWOCs within the LMWM. Fatty acids formed the core of the major fraction in all species: they were among the top three compounds in all 11 macrophytes and ranked first or second in 10 of 11, highlighting the lipid module as a universal “structure–signaling–defense/allelopathy” hub in aquatic plants. Also, an analysis of the ecological-biochemical role of the main major LMWOCs in the studied aquatic macrophytes is presented. Overall, the data offer a comparable, ecologically oriented framework for interpreting chemical regulation of communities in macrophyte-dominated habitats and for selecting target compounds/species for subsequent bioassay and field studies.

The low molecular weight metabolome (LMWM) of Lobelia dortmanna L. (Campanulaceae, Magnoliophyta)—a relic aquatic macrophyte listed in the Red Data Books of the Russian Federation and the Republic of Belarus—has been studied for the first time using the GC/MS technique. This macrophyte grows in oligotrophic lakes in the northwest of Vologda oblast, Russia. We have discovered 127 volatile low molecular weight organic compounds (VOCs), and 13 of the main ones accounted for 77.23% of the overall VOC content (198.75 µg/g of dry plant mass). The main components of the LMWM are represented by carboxylic acids and hydrocarbons. The presence of a large number of biologically active metabolites with a high concentration in L. dortmanna LMWM may indicate a significant effect of this plant on the hydrobiocenoses of the littoral zone of oligotrophic lakes. Further research into the LMWM of aquatic macrophytes in oligotrophic lakes, a valuable renewable resource, is needed to assess the background characteristics of the natural environment for the more effective monitoring of the ecological status of water bodies in northwestern Russia and rational use of their biological resources.

Freshwater macrophytes shape not only the morphological “architecture” of shallow-water ecosystems but also their chemical milieu via low-molecular-weight organic compounds (LMWOCs) that may regulate phytoplankton, periphyton, and the microbiome within the leaf/shoot diffusive boundary layer and the surrounding water column. In this study, GC–MS (gas chromatography–mass spectrometry) was used to identify major LMWOCs of the low-molecular-weight metabolome (LMWM) in 11 widely distributed macrophyte species (Myriophyllum spicatum L., Sparganium emersum Rehm., Sparganium gramineum Georgi, the hybrid Sparganium × foliosum A. A. Bobrov, Volkova, Mochalova et Chemeris, Persicaria amphibia (L.) Delarbre, Potamogeton perfoliatus L., Nuphar lutea (L.) Sibth. & Sm., Potamogeton pectinatus L., Potamogeton natans L., Lobelia dortmanna L., and Ceratophyllum demersum L.). Compounds contributing more than 1% to the total LMWOCs pool were considered major, increasing the ecological realism of interpretations by focusing on metabolites more likely to reach effective concentrations in the plant microenvironment. For interspecific comparisons, the maximum recorded values of relative abundance and concentrations were used to estimate species “potential”. In total, 137 major LMWOCs were detected (four remained unidentified), and their numbers varied markedly among taxa (from 11 in Nuphar lutea to 71 in P. perfoliatus). Similarity analyses (Jaccard, Sørensen–Czekanowski, Morisita–Horn) indicated that similarity based on compound lists and similarity based on dominance structure may diverge, reflecting differences between the “LMWOCs set” and the quantitative architecture of LMWOCs within the LMWM. Fatty acids formed the core of the major fraction in all species: they were among the top three compounds in all 11 macrophytes and ranked first or second in 10 of 11, highlighting the lipid module as a universal “structure–signaling–defense/allelopathy” hub in aquatic plants. Also, an analysis of the ecological-biochemical role of the main major LMWOCs in the studied aquatic macrophytes is presented. Overall, the data offer a comparable, ecologically oriented framework for interpreting chemical regulation of communities in macrophyte-dominated habitats and for selecting target compounds/species for subsequent bioassay and field studies.