СОВРЕМЕННАЯ АККУМУЛЯЦИЯ ТОРФА В РЯМАХ ОЛИГОТРОФНЫХ БОЛОТ ЮГА ЛЕСНОЙ ЗОНЫ ЗАПАДНОЙ СИБИРИ КАК ОТКЛИК НА ИЗМЕНЕНИЯ КЛИМАТА

• Main Authors: Прейс, Юлия, Сороковенко, Ольга, Бобров, Владислав
• Format: Text
• Language: unknown
• Published: Федеральное государственное бюджетное образовательное учреждение высшего профессионального образования "Национальный исследовательский Томский государственный университет" 2010
• Subjects: ТОРФ; АККУМУЛЯЦИЯ; РЯМ; ЗАПАДНАЯ СИБИРЬ; КЛИМАТ; taiga; Siberia
• Online Access: http://cyberleninka.ru/article/n/sovremennaya-akkumulyatsiya-torfa-v-ryamah-oligotrofnyh-bolot-yuga-lesnoy-zony-zapadnoy-sibiri-kak-otklik-na-izmeneniya-klimata; http://cyberleninka.ru/article_covers/13979482.png

Проведена оценка средней скорости прироста и аккумуляции торфа и углерода в рямах олиготрофных болот юга лесной зоны Западной Сибири за последний 40-45-летний период по данным детальных исследований и датирования по 137Cs и экстремумам зольности 23 монолитов торфа. Выявлено значительное варьирование этих показателей в зависимости от исходных водных режимов и механизмов отклика на климатические изменения. Net ecosystem productivity (NEP) was studied in 20 oligotrophic low-pine ericaceous dwarf shrub Sphagnum fuscum biocoenoses (riams) and their succession variants of 6 bogs located in the southern taiga and sub-taiga of Western Siberia. Peat samples were taken from 23 peat monoliths with a 1-3 cm step. Analysis of macrofossils plant remains, degree of peat decomposition (R), ash contents (A) and dry bulk density (P) have been made in each peat sample. Six peat cores have been 137Cs-dated. Depths of maxima of the 137Cs content and peat ash coincide. The age of the layer with ash content extremum, but without coal content, was dated to 1963 in other peat sections. NEP was estimated for the last 40-45 years. Significant variation of average rate of peat growth (Vgr), peat accumulation (Vac peat) and carbon accumulation (Vac С) has been revealed. It was determined that it is caused by the distinction in both initial water regimes and mechanisms of the response to water level recessions or its increase during last years. As their response to climatic changes, five groups of riams have been distinguished in view of the changes of vegetation, NEP and peat properties. Group I includes endodynamic riams with minimal response. Diagnostic characteristics (DA) of this group are: decrease of R and P towards bog surface, high parameters of NEP (Vgr 6,0-11,0 mm yr-1, Vac peat199-223 g m-2 yr-1 and Vac С 87-99 g m-2 yr-1). Group II includes riams with positive response. DA are: constant P and decrease R towards bog surface; maximal parameters of NEP (6,5-9,0 mm yr-1; 190-267 and 83-119 g m-2 yr-1), group III includes riams with double antidromic response, as a result of drying and the subsequent flooding. DA are the presence of hydrophilic plant species; lower parameters of NEP (6,0-8,3 mm yr-1; 144-166 and 64-73 g m-2 yr-1). Group IV includes riams with strong negative response. DA are the domination of Sphagnum fuscum and Lichens; high parameters of P and R and their increase towards bog surface; low parameters of NEP (2,4-4,9 mm yr-1; 78-140 and 33-60 g m-2 yr-1). Group V includes riams with maximal negative response. DA are the domination of Pleurozium schreberi; sharp, narrow extrema of A, R and P; minimal parameters of NEP (1,4-3,4 mm yr-1, 72-144 and 27-58 g m-2 yr-1). Thus, riam responses to climatic changes have both positive and negative trends. The absence of synchronism and different degree of change of the functional condition of riams are caused, first of all, by the distinctions of their initial water regimes, determining the beginning, duration and response value to climatic changes. The data show that such bogs have fast response and may be used as indicators for reconstruction of climate even on interdecadal scale.