摘要：Forest ecosystems cover about 30% of the Earth's surface and provide important ecosystem goods and services. Forest traits: specific leaf area (SLA), leaf weight ratio (LWR) and growth index (It) are among the key indicators of forest ecosystems functioning. The investigation deals with meta-analysis (including ANOVA and RDA analysis) for 20 Bulgarian locations of Quercus cerris L. and Q. frainetto Ten. forests. The results are verified with the data from TRY database. For all analysis as a response, variables are chosen selected indexes - SLA, LWR and It and as explanatory variables - listed characteristics of locations: latitude, longitude, altitude, precipitation and temperature. The positive correlation of growth index and SLA and negative - with altitude for all locations are obtained. The growth index correlated negatively with LWR and positively with longitude only for Bulgarian locations. The established dependences are indispensable for higher precision of the ongoing analyzes, filling the gaps of data and creating a new generation of vegetation models.
