Five permanent sample plots (SPs; 200–250 trees per plot) were established in middle-aged high-grade suburban pine stands near the industrial city of Krasnoyarsk, Siberia, Russia. Needle damage, inventory parameters of the stands, and the defense response of the stem phloem were evaluated annually for the years 2002–2019 and attributed to acute or chronic toxic exposures (creeping fire or industrial pollutants, respectively). The results form a basis for using trees as bioindicators. A newly elaborated stem lesion test was formed from a hypothesis on the upward sugar transport for the regeneration of an injured crown, based on Eschrich’s model of bidirectional sugar transport in the phloem. The formation of a phloem lesion was induced by inoculation of the stem with a mycelial extract of the ophiostomatoid fungus Ceratocystis laricicola. The lesion length and its shift relative to the inoculation hole were measured. An increase in the length of needles at early stages of stand weakening by pollutants was found to correspond to the hormesis model (Selye’s adaptation syndrome). A possibility of assessing the chronology of pollutant toxicity and the duration of the recovery period after creeping fire was shown.
Abstract. Needle cast caused by fungi of the genus Lophodermium Chevall. is a common disease in pine trees in Siberia. Regression analyses relating needle cast events to climatic variables in [1997][1998][1999][2000][2001][2002][2003][2004][2005][2006][2007][2008][2009][2010] showed that the disease depended most on precipitation of two successive years. Temperature conditions were important to trigger the disease in wetter years. We used our regional bioclimatic envelope model and IPCC scenarios to model the needle cast distribution and its outbreaks in the 21st century. In a warming climate, the needle cast range would shift northwards. By 2020, needle cast outbreaks would already have damaged the largest forest areas. But outbreak areas would decrease by 2080 because the ranges of modeled pathogen and Scots pine, the disease host, would separate: the host tree progression would be halted by the slower permafrost retreat, which would in turn halt the potential pathogen progression.
This article is part of the special series "Environmental Monitoring on Global and Local Scales." The series documents cases of the current state of environmental assessment and tracking using different approaches: in situ monitoring, geoinformation modeling, and risk-based assessment. The work was originally presented at the conference "Ecological Monitoring: Methods and Approaches," held September 2021 in Krasnoyarsk, Russia, and co-organized with the European and Russian-Language Branches of Society of Environmental Toxicology and Chemistry.
By the method of exhaustive hydroparodistillation, essential oil was obtained from Siberian pine (Pinus sibirica Du Tour) and Siberian fir (Abies sibirica Ledeb.), growing on the territory of the Krasnoyarsk territory. Separate fractions of oil were obtained: the first one after 45 min from the beginning of distillation, the second – after 2 hours, the third – after 5 hours, the fourth-after 10 hours, the fifth fraction was collected after the end of hydrodistillation. The antimicrobial activity of separate fractions of essential oil of P. sibirica and A. sibirica was studied against strains of opportunistic microorganisms: Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae, Staphylococcus aureus 209p, Micrococcus luteus, Acinetobacter baumanii, Candida albicans. The performed studies showed that all the studied samples of essential oils showed either bactericidal or bacteriostatic activity against the strains of microorganisms taken in the experiment, except Pseudomonas aeruginosa. The type of activity displayed depended on the type of strain and sample of essential oil. It is noted that the sensitivity of the experimental strains to the components of the essential oils of P. sibirica and A. sibirica decreases during the transition from the first to the last fraction. We assume that, apparently, this is due to a decrease in the number of monoterpenes in the composition of oils.To study the antiradical activity, the reaction of essential oil components with a stable free 2,2-diphenyl-1-picrylhydrazyl radical was used. Antiradical activity of both whole essential oils of P. sibirica and A. sibirica and their separate fractions was established. There was an increase in antiradical activity with a decrease in the content of monoterpenes in the composition of essential oil.
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