The dynamics of the phytoproduction process in the period from 1700 to 2020 AD was defined by means of dendrochronological analysis of fifty-five Siberian larch cores taken in a sparse cedar-larch herbaceous forest within the city of Nadym and on a sample plot twenty-six kilometers from Nadym in a sparse cedar-larch green moss-lichen forest. Comparison of generalized dendrochronologies allows us to conclude that before the active growth of the city in 1972, the increase in the control area was more variable and more by 1/3 than within the city. With the expansion of the city over the past 50 years, the increase in productivity within the city bounda-ries exceeded 2,4 times compared to the control area. Analysis of the statistical characteristics of the samples was carried out, showing the significance of the influence of the city on the growth of larches. The method of spatial air temperature differences between Nadym and Tarko-Sale, located 250 km to the southeast, was used. Warming in winter in Nadym was 2,8°C, which is 0,7°C more than in Tarko-Sale. The warming in the summer period is almost the same and amounted to 1,3-1,4°C with a standard deviation of the long-term series of 1,8°C. An increase in air temperature in Nadym could not but affect the growth of larch. The other factors for the growth of bioproductivity are the warming effect of the city (reduction of energy costs for evaporation and an increase in energy costs for heat exchange between the underlying surface and the atmosphere) and agro-forestry reclamation of natural forests.