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The effects of different irrigation regime on survival and growth of holm oak (Quercus ilex L.) plantation was studied in a semi-arid Mediterranean climate condition located in Marzanabad region (Mazindaran province). This study was done as Randomized Complete Block design with three replicates and four treatments, including no-irrigation and irrigation with 10, 20 and 30 day periods during dry months in growing seasons (spring and summer). Climate data analysis showed that a severe frost and three to six dry months annually occurred in growing season during study years (2006-2010). Height growth and survival of saplings were measured every year and at the end of 5th year. Analysis of data showed that irrigation treatment with 10-day intervals with a 65% survival is preferred and differences are significant (p

The alkali-basalt and basaltic trachy-andesites volcanic rocks of south Marzanabad were erupted during Cretaceous in central Alborz, which is regarded as the northern part of the Alpine-Himalayan orogenic belt. Based on petrography and geochemistry, en route fractional crystallization of ascending magma was an important process in the evolution of the volcanic rocks. Geochemical characteristics imply that the south Marzanabad alkaline basaltic magma was originated from the asthenospheric mantle source, whereas the high ratios of (La/Yb) N and (Dy/Yb) N are related to the low degree of partial melting from the garnet bearing mantle source. Enrichment pattern of Nb and depletion of Rb, K and Y, are similar to the OIB pattern and intraplate alkaline magmatic rocks. The K/Nb and Zr/Nb ratios of volcanic rocks range from 62 to 588 and from 4.27 to 9 respectively, that are some higher in more evolved samples which may reflect minor crustal contamination. The isotopic ratios of Sr and Nd respectively vary from 0.70370 to 0.704387 and from 0.51266 to 0.51281 that suggest the depleted mantle as a magma source. The development of south Marzanabad volcanic rocks could be related to the presence of extensional phase, upwelling and decompressional melting of asthenospheric mantle in the rift basin which made the alkaline magmatism in Cretaceous, in northern central Alborz of Iran. [ABSTRACT FROM AUTHOR]