The role of planted forests in improving the productive capacity and ecological potential of Scots pine boreal forests in the Middle Volga Region

New Zealand Journal of Forestry Science

Table 6 Estimates of model parameters and goodness of fit statistics for the relationship between growing stock and stand age for planted and natural Scots pine stands growing on different site types (data reproduced from Romanov, Nureeva & Eremin 2013)

Origin	Parameter	Actual stock				Standard stock
Origin	Parameter	А₁	А₂	В₂	С₂	А₁	А₂	В₂	С₂
Planted	Number of forest sites	2206	3892	1423	9927	2206	3892	1423	9927
	К	216	311	400	318	409	520	593	573
	a	4.94	4.32	3.5	5.55	3.11	3.08	2.9	3.59
	b	3.5	3.34	2.53	3.23	2.47	2.56	2.21	2.41
	М ₁₀₀ ^a, m³	211	297	370	315	365	461	524	535
	R ²	0.844	0.907	0.922	0.878	0.907	0.953	0.953	0.954
Natural	Number of forest sites	736	4701	2717	2088	736	4701	2717	2088
	К	215	248	270	304	419	426	462	518
	a	5.75	9.14	8.96	4.3	3.41	5.4	4.68	3.23
	b	5.59	15.97	11.51	2.87	2.8	5.2	3.51	2.35
	М ₁₀₀, m³	211	248	248	292	382	416	447	471
	R ²	0.835	0.715	0.663	0.688	0.929	0.905	0.862	0.829

The actual stock is the true mean stock volume with relative density from 0.5 to 0.9. The standard stock is the calculated stock for plantations with relative density 1.0. The timber lands were chosen from the seven forests listed in Tables 3, 4, 7 and 8
^a M ₁₀₀—the productivity for 100-year-old stands. M ₁₀₀ (years) is a calculated for the plantations in the age of 100-year stock