What was done
Working in the Komi Republic in the northeast European sector of Russia (59°12'-68°25'N, 45°25'-66°10'E), the authors (1) collected discs and cores from 151 Siberian spruce trees and 110 Scots pines from which they developed ring-width chronologies that revealed yearly changes in forest productivity, (2) developed satellite-based time series of Normalized Difference Vegetation Index (NDVI) for the months of June, July, August over the period 1982-2001, (3) correlated their site-specific ring-width-derived productivity histories with same-site NDVI time series, (4) used the resulting relationship to establish six regional forest productivity histories for the period 1982-2001, and (5) compared the six regional productivity trends over this period with corresponding-region temperature and precipitation trends.

What was learned
For all six vegetation zones of the Komi Republic, Lopatin et al. report that the 1982-2001 trends of integrated NDVI values from June to August were positive, and that the "increase in productivity reflected in [the] NDVI data [was] maximal on the sites with increased temperature and decreased precipitation."

What it means
The three scientists note that "several studies (Riebsame et al., 1994; Myneni et al., 1998; Vicente-Serrano et al., 2004) have shown a recent increase in vegetation cover in different world ecosystems." Many similar reports are also discussed under the general heading Greening of the Earth in our Subject Index. What is special about the study of Lopatin et al., as they describe it, is that "in Europe, most forests are managed, except for those in northwestern Russia [the location of their work], where old-growth natural forests are dominant (Aksenov et al., 2002)." Consequently, and because of their positive findings, they say we can now conclude that "productivity during recent decades also increased in relatively untouched forests," where non-management-related "climate change with lengthening growing season, increasing CO2 and nitrogen deposition" are the primary determinants of changes in forest productivity.

References
Aksenov, D., Dobrynin, D., Dubinin, M., Egorov, A., Isaev, A., Karpachevskiy, M., Laestadius, L., Potapov, P., Purekhovskiy, P., Turubanova, S. and Yaroshenko, A. 2002. Atlas of Russia's Intact Forest Landscapes. Global Forest Watch Russia, Moscow.

Myneni, R.B., Tucker, C.J., Asrar, G. and Keeling, C.D. 1998. Interannual variations in satellite-sensed vegetation index data from 1981 to 1991. Journal of Geophysical Research 103: 6145-6160.

Riebsame, W.E., Meyer, W.B. and Turner, B.L. 1994. Modeling land-use and cover as part of global environmental-change. Climatic Change 28: 45-64.

Vicente-Serrano, S.M., Lasanta, T. and Romo, A. 2004. Analysis of spatial and temporal evolution of vegetation cover in the Spanish central Pyrenees: Role of human management. Environmental Management 34: 802-818.