The soil supports plants, is the physical determinant of root growth and extent, and is the main reservoir for plant-available water and nutrients. Therefore, the soil controls the availability of most essential plant nutrients. It regulates availability by means of biophysiochemical processes, which are functions of soil and plant properties. This chapter introduces the concept of soil nutrien...

the relationship between topography, soil factors, and distribution of ecological vegetation groups in the nodoushan arid rangelands of yazd province (iran) was investigated. the present species were recorded in each vegetation group using a randomized-systematic sampling method. plant cover and density were estimated quantitatively using the transect and quadrate methods, and the two-way indic...

in temperate forests canopy gaps play an important role in driving stand dynamics. the purpose of this research was to compare soil characteristics in forest gaps with several size and its relation to beech regeneration density in lalis forest, chalous. in order to investigate factors, three gap sizes as small gap (200 m2), medium gap (400 m2), and large gap (600 m2) with three replicate were s...

introduction saffron is one of the most economically important plants across iran and all over the world. the most important cultivated areas of saffron are in khorasan-e razavi and southern khorasan provinces (jihad keshavarzi khorasan razavi, 2013). the corm is the reservoir of photosynthetic materials and plays an important role in the saffron life cycle. corm size and physicochemical charac...

Long-term investigations of soil moisture at different precipitation patterns in the black soil in Hailun county, Northeast China were made. This area is an important base for marketable grains production due to a short cultivation history, high soil organic matter content, and high yield potential. In this region, precipitation is the principal water source during the cropping season, hence so...

In this study we characterized spatial heterogeneity of soil carbon and nitrogen pools, soil moisture, and soil pH of the first 15 cm of the soil profile; depth of the organic horizon; forest floor covers; and understory vegetation abundances in three sites (1999, 1987 and 1920 wildfires) of a boreal forest chronosequence of interior Alaska. We also investigated the cross-dependence between und...

the effects of range management plans (rmp) on soil and vegetationcharacteristics were studied in eshtehard rangelands at alborz province. the parameters ofyield, canopy cover, range condition and trend, bulk density, organic matter (om%),nitrogen (n), phosphorous (p) and potassium (k) were estimated on soil samples in sitesof ghenzel cheshmeh as rmp and sanctum of rahmanyeh village. the data w...