Effects of soil compaction on growth variables in Cappadocian maple(Acer cappadocicum) seedlings

This study investigates the effects of increasing soil penetration resistance(SPR) on seedling morphology and seedling architecture. When seedlings of deciduous Cappadocian maple(Acer cappadocicum Gled.) were grown in a greenhouse in a loamy soil under a wide range of soil compactions, all morphological variables studied changed significantly with increasing SPR. The relationships between increasing SPR and all morphological responses except lateral root length followed a negative quadratic curve. All biomass variables except lateral root biomass showed a bell-shaped response with respect to SPR, with a maximum biomass variable between 0.6 and1.2 MPa, decreasing at higher soil compaction values. All allocation ratios were significantly affected by soil penetration resistance. Biomass allocation to roots was also affected by soil compaction. There was not a significant relationship between the specific stem length and increasing soil penetration resistance. The specific root length showed two trends to increasing SPR; it first decreased in response to the moderate compaction treatment(up to about 1.2 MPa), then increased significantly. We concluded that increasing soil compaction caused morphological changes to root and shoot sections of A.cappadocicum seedlings.

Dynamics of fine root N,Pand K in high elevation forests of central Himalaya

Fine root nutrient dynamics were calculated for one year in three high elevation forests of Indian central Himalaya. In all sites, fine root nutrient concentrations varied with respect to forests and seasons. N concentration in fine roots was highest followed by K and P. In general, fine roots showed their highest nutrient concentrations during the rainy season and lowest in winter. Higher nutrient concentrations during the rainy season may be related to favorable moisture and temperature regimes which in turn results in increased plant growth activities. Present fine root nutrient amounts and nutrient uptake values decreased towards high elevations. In general, the highest amounts of nutrients in both live and dead fine roots were observed in September and the lowest in the month of June. Turnover rates of the nutrients in the fine roots also decreased with an increase in elevation.