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The exchange of carbon dioxide (CO2) between the atmosphere and a forest after disturbance by wind throw in the western Russian taiga was investigated between July and October 1998 using the eddy covariance technique. The research area was a regenerating forest (400 m × 1000 m), in which all trees of the preceding generation were uplifted during a storm in 1996. All deadwood had remained on site after the storm and had not been extracted for commercial purposes. Because of the heterogeneity of the terrain, several micrometeorological quality tests were applied. In addition to the eddy covariance measurements, carbon pools of decaying wood in a chronosequence of three different wind throw areas were analysed and the decay rate of coarse woody debris was derived. During daytime, the average CO2 uptake flux was −3 µmol m−2s−1, whereas during night‐time characterised by a well‐mixed atmosphere the rates of release were typically about 6 µmol m−2s−1. Suppression of turbulent fluxes was only observed under conditions with very low friction velocity (u* ≤ 0.08 ms−1). On average, 164 mmol CO2 m−2d−1 was released from the wind throw to the atmosphere, giving a total of 14.9 mol CO2 m−2 (180 g CO2 m−2) released during the 3‐month study period. The chronosequence of dead woody debris on three different wind throw areas suggested exponential decay with a decay coefficient of −0.04 yr−1. From the magnitude of the carbon pools and the decay rate, it is estimated that the decomposition of coarse woody debris accounted for about a third of the total ecosystem respiration at the measurement site. Hence, coarse woody debris had a long‐term influence on the net ecosystem exchange of this wind throw area. From the analysis performed in this work, a conclusion is drawn that it is necessary to include into flux networks the ecosystems that are subject to natural disturbances and that have been widely omitted into considerations of the global carbon budget. The half‐life time of about 17 years for deadwood in the wind throw suggests a fairly long storage of carbon in the ecosystem, and indicates a very different long‐term carbon budget for naturally disturbed vs. commercially managed forests.

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Zentral'no-Lesnoj Biosphere Nature Reserve is situated in the Russian plain, in the southern part of Valdaj Hills, 56°26'-56°36'N-32°42'-33°05'E, 240-300 m alt.; its territory is 230 sq. km. 150 species of mosses and 45 hepatics have been found in the reserve (not including doubtful literature records). An annotated list and dicussion on general bryophyte complexes of reserve are given. A collection of V. Medvedskaya-Romanenko, made in 1938 allows evaluation of changes in bryoflora since that time. The main changes: (1) epixylic hepatic flora has become poorer, and some rare species (Bazzania tricrenata, Di plophyllum taxifolium) are probably disappeared; (2) Hamatocaulis vernicosus, a moss of minerotrophic bogs, has not been recollected; (3) southern epi phytic mosses have probably become rarer (Anomodon viticulosus, Hypnum vaucheri haven't been found); Leucodon sciuroides and Anomodon longifolius were found on only one trunk each. Pylaisiella selwynii can be considered to have recently become established in the flora of this area. Ðåçþìå Центрально-Лесной биосферный заповедник расположен на Русской равнине, у южных отрогов Валдайской возвышенности, 56°26'-56°36'ñ. ø.-32°42'-33°05'â. ä., 240-300 ì íàä óð. ì.; åãî òåððèòîðèÿ ñîñòàâëÿåò 230 êâ. êì.  çàïîâåäíèêå âûÿâëåíî 150 âèäîâ ìõîâ è 45 ïå÷åíî÷íèêîâ (íå âêëþ÷àÿ ñîìíèòåëüíûå ëèòåðàòóðíûå äàííûå). Ïðèâîäèòñÿ àííîòèðîâàííûé ñïèñîê âèäîâ è î÷åðê îñíîâíûõ ìîõîâûõ êîìïëåêñîâ çàïîâåäíèêà. Êîëëåêöèÿ Â. Ìåäâåäñêîé-Ðîìàíåíêî, ñîáðàííàÿ â 1938 ã., ïîçâîëÿåò îöåíèòü èçìåíåíèÿ âî ôëîðå, ïðîèñøåäøèå ñ òîãî âðåìåíè. Îñíîâíûìè èç íèõ ìîaeíî ñ÷èòàòü ñëåäóþùèå: (1) ñòàëà áåäíåå ôëîðà ýïèêñèëüíûõ ïå÷åíî÷íèêîâ, íåêîòîðûå èç êîòîðûõ, î÷åâèäíî, èñ÷åçëè (Bazzania tricrenata, Di plophyllum taxifolium); (2) Hamatocaulis vernicosus, òèïè÷íûé ïðåäñòàâèòåëü ìèíåðîòðîôíûõ áîëîò, èñ÷åç; (3) òàêaeå ðåaeå ñòàëè ýïèôèòû ñ áîëåå þaeíûì ðàñïðîñòðàíåíèåì (Anomodon viticulosus è Hypnum vaucheri íå áûëè íàéäåíû, à Leucodon sciuroides è Anomodon longifolius áûëè íàéäåíû òîëüêî íà îäíîì äåðåâå êàaeäûé). Pylaisiella selwynii, ïî-âèäèìîìó, íåäàâíî ïðîíèêëà â äàííûé ðàéîí.

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