scholarly journals MONITORING OF ATMOSPHERIC AND SOIL WATER COMPOSITION IN FOREST ECOSYSTEMS: MILESTONES AND OUTLOOK

2021 ◽  
Vol 1 (4) ◽  
pp. 1-25
Author(s):  
V.V. Ershov ◽  
Keyword(s):  
Chemical Composition ◽  
Species Composition ◽  
Forest Ecosystems ◽  
Atmospheric Fallout ◽  
Water Composition ◽  
Long Term Trends ◽  
Industrial Regions ◽  
Composition Changes ◽  
Lysimetric Waters

The article provides an overview of Russian and foreign studies on assessment of the composition of atmospheric fallout and soil waters in forest ecosystems. The conclusion was made that little attention is given to the transformation of precipitation chemical composition by forest ecosystems, taking into account the influence of the species composition of the stand and the mosaic structure of the biogeocenosis (areas below the crowns, between the crowns, and open sites). European studies usually look at long-term development of the composition of atmospheric fallout and lysimetric waters, detecting long-term trends in composition changes of atmospheric and soil waters and identifying the factors driving these changes. In Russia, no such long-term (lasting for more than 10 years) continuous observations on the effect of man-made pollution on the composition and properties of atmospheric and soil waters were carried out. This task is very relevant for Russia and, especially, for its industrial regions.

scholarly journals The sensitivity of PM<sub>2.5</sub> acidity to meteorological parameters and chemical composition changes: 10-year records from six Canadian monitoring sites

2019 ◽  
Author(s):  
Ye Tao ◽  
Jennifer G. Murphy
Keyword(s):  
Chemical Composition ◽  
Meteorological Parameters ◽  
Inorganic Ions ◽  
Water Soluble ◽  
Seasonal Cycles ◽  
Accuracy And Precision ◽  
Different Seasons ◽  
Water Soluble Inorganic Ions ◽  
Composition Changes

Abstract. Aerosol pH is difficult to measure directly but can be calculated if the chemical composition is known with sufficient accuracy and precision to calculate the aerosol water content and the H+ concentration through ion balance. In practical terms, simultaneous measurements of at least one semi-volatile constitute, e.g. NH3 or HNO3, are required to provide a constraint on the calculation of pH. Long-term records of aerosol pH are scarce due to the limited monitoring of NH3 in conjunction with PM2.5. In this study, 10-year (2007–2016) records of pH of PM2.5 at six eastern Canadian sites were calculated using the E-AIM II model with the input of gaseous NH3, gaseous HNO3 and major water-soluble inorganic ions in PM2.5 provided by Canada's National Air Pollution Surveillance (NAPS) Program. Clear seasonal cycles of aerosol pH were found with lower pH (~2) in summer and higher pH (~3) in winter consistently across all six sites, while the day-to-day variations of aerosol pH were higher in winter compared to summer. Tests of the sensitivity of aerosol pH to meteorological parameters demonstrate that the changes in ambient temperature largely drive the seasonal cycle of aerosol pH. The sensitivity of pH to chemical composition shows that pH has different responses to the changes in chemical composition in different seasons. During summertime, aerosol pH was mainly determined by temperature with limited impact from changes in NHx or sulfate concentrations. However, in wintertime, both meteorological parameters and chemical composition contribute to the variations in aerosol pH, resulting in the larger variation during wintertime. This study reveals that the sensitivity of aerosol pH to chemical composition is distinctly different under different meteorological conditions and needs to be carefully examined for any particular region.

Long-term trends in species composition and diurnal migration of dinoflagellates in Lake Tovel (Trentino, Italy)

Hydrobiologia ◽  
2003 ◽  
Vol 502 (1-3) ◽  
pp. 357-366 ◽  
Author(s):  
Giovanna Flaim ◽  
Eugen Rott ◽  
Flavio Corradini ◽  
Giambattista Toller ◽  
Basilio Borghi
Keyword(s):  
Species Composition ◽  
Lake Tovel ◽  
Long Term Trends ◽  
Diurnal Migration

scholarly journals The Vasyugan Bog North-Eastern Part Hydro/chemical Regime Specific Features between the Bakchar and Iksa Rivers (Western Siberia)

2018 ◽  
Author(s):  
Keyword(s):  
Chemical Composition ◽  
Vegetation Period ◽  
Water Composition ◽  
North Eastern ◽  
Bog Waters ◽  
Bog Water ◽  
Ph Increase ◽  
Seasonal Indices ◽  
Composition Changes ◽  
North Eastern Part

Analysis of the hydro/chemical regime and spatial regularities of the water composition changes in the Vasyugan Bog North-Eastern part between the Bakchar and Iksa rivers is presented. It has been noted that the chemical composition transformation with water class, group and type during the year is a special feature of the high bog hydro/chemical regime. Within the bog limits three clusters have been identified by bog waters chemical composition characteristics on the basis of the cluster analysis. Reliable differences between the tree clusters have been determined by the mineralization amount, Са2+, Mg2+, Feобщ, NH4 +, NO3 - ions, humic and fulvene acids, Сорг and СО2 content. Analysis of the seasonal indices has demonstrated that during the vegetation period two significant maximal peaks of the bog water seasonal wave of chemical composition occur, namely in March and September. It has been noted that that the near-ground air temperature sum increase more than 10 ºС is accompanied by the pH increase in the high bog water, increase of СО2, ammonia, sulphate, iron ions, and organic matter (humic and fulvene acids, Сорг).

scholarly journals Pests of flower-decorative plants in the collections of Polar-Aalpine Botanical garden

2020 ◽  
pp. 125-134
Author(s):  
N. S. Rak ◽  
S. V. Litvinova
Keyword(s):  
Species Composition ◽  
Ornamental Plants ◽  
Food Preferences ◽  
Botanical Garden ◽  
Trophic Relationships ◽  
Heliothrips Haemorrhoidalis ◽  
The Status ◽  
Macrosiphum Rosae ◽  
Composition Changes

The results of long-term entomological observations at nurseries and in the collection greenhouse of PABSI are presented. The species composition of pests in the collections of open and closed ground of flower and ornamental plants in thePolar-AlpineBotanical gardenwas determined. The dominant invertebrates in nurseries are: Deroceras reticulatum Mtill., Eriophyes padi (Nal), Macrosiphum rosae L., Philaenus spumarius L., Gonioctena quinquepunctata F., Gonioctena pallida L., in greenhouses - Brevipalpus obovatus Donn., Neomyzus circumflexus Buckt., Myzodes persicae Sulz., Heliothrips haemorrhoidalis Bouche. Long-term observations of the state of flower and ornamental plants in greenhouses have shown that not only the species composition changes, but also the status of pests. An important role in the formation of the artificial biocenosis of the greenhouse is played by the food preferences of phytophages. Regular surveys revealed the presence of pests on plants of 41 families. The distribution of plants by the degree of pest population depending on the life form is presented. The most actively populated by the species of tree and shrub groups. The presented species composition of pests of flower and ornamental plants of open and closed ground can not be considered definitively studied, since changes in the trophic relationships of pests were noted during the study period.

scholarly journals Trends of particulate matter (PM<sub>2.5</sub>) and chemical composition at a regional background site in the Western Mediterranean over the last nine years (2002–2010)

2012 ◽  
Vol 12 (4) ◽  
pp. 10995-11033 ◽  
Author(s):  
M. Cusack ◽  
A. Alastuey ◽  
N. Pérez ◽  
J. Pey ◽  
X. Querol
Keyword(s):  
Particulate Matter ◽  
Chemical Composition ◽  
Saharan Dust ◽  
Sea Spray ◽  
Crustal Material ◽  
North East ◽  
Regional Background ◽  
Long Term Trends ◽  
The Mean

Abstract. The time variability and long term trends of PM2.5 (particulate matter of diameter <2.5 μm) at various regional background (RB) sites across Europe are studied and interpreted in this work. Long-term trends of PM2.5 concentrations are relatively scarce across Europe, with few studies outlining the changes measured in PM2.5 concentrations over a significant period of time. To this end, data on mean annual levels of PM2.5 measured at Montseny (MSY, North East Spain) and various RB sites in Spain and Europe are evaluated and compared, and subsequently analysed for statistically significant trends. The MSY site registered higher average PM2.5 levels than those measured at a selection of other RB sites across Spain, Portugal, Germany and Scandinavia, but lower than those measured in Switzerland, Italy and Austria. Reductions in PM2.5 were observed across all stations in Spain and Europe to varying degrees. MSY underwent a statistically significant reduction since measurements began, indicating a year-on-year gradual decrease (−3.7 μg m−3, calculated from the final year of data compared to the mean). Similar trends were observed in other RB sites across Spain (−1.9 μg m−3). Reductions recorded in PM2.5 across Europe were varied, with many experiencing gradual, year-on-year decreases (−1.8 μg m−3). These reductions have been attributed to various causes: the introduction and implementation of pollution abatement strategies in EU member states, the effect of the current economic crisis on emissions of PM2.5 and the influence of anomalous meteorology observed during the winters of 2009 and 2010. The North Atlantic Oscillation (NAO), a large scale meteorological phenomenon most prevalent during winter, was observed to influence the frequency of Saharan dust intrusions across the Iberian Peninsula. Chemical composition of PM2.5 at MSY is characterised by high levels of organic matter (OM) and sulphate, followed by crustal material, nitrate and ammonia. Sea Spray and finally elemental carbon (EC) comprised a minor part of the total PM2.5 mass. Statistical trend analysis was performed on the various chemical components of PM2.5 recorded at MSY to determine which components were accountable for the decrease in PM2.5 concentration. It is shown that OM underwent the largest decrease over the time period with a statistically significant trend (−1.3 μg m−3 of the mean), followed by sulphate (−0.8 μg m−3), ammonium (−0.5 μg m−3) and nitrate (−0.4 μg m−3). Conversely, sea spray, EC and crustal material reductions were found to be negligible.

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