Table 3. Decomposition of true gamma diversity (total species diversity in a site) into true alpha diversity (mean species density per quadrat) and true beta diversity (effective number of compositionally distinct quadrats) in 11 old-growth beech forest stands in southern Europe.

	alpha	beta	gamma	alpha	beta	gamma
Abeti Soprani	19.04	3.26	62	9.17	2.63	24.13
Biogradska Gora	15.76	3.24	51	4.93	2.32	11.43
Valle Cervara	11.24	4.09	46	4.68	1.97	9.23
Monte Cimino	13.08	2.98	39	4.41	2.88	12.68
Collemeluccio	12.92	4.26	55	2.86	1.74	4.98
Fonte Novello	9.08	3.19	29	3.15	1.54	4.87
Gargano-Pavari	5.48	4.01	22	2.85	2.36	6.73
Monte di Mezzo	7.16	4.47	32	3.49	2.56	8.96
Muniellos	5.24	4.77	25	1.46	1.27	1.84
Perucica	15.96	2.32	37	3.45	1.24	4.28
Sassofratino	14.60	3.63	53	8.04	3.05	24.50

Diversities were quantified at q = 0 (which gives more weight to rare species) and q = 2 (which gives more weight to abundant species).