Comparison of some soils physicochemical properties in mixed and monocultures to non – cultivation in Zagros forests (case study Zagros forest, Iran)

摘要

Forest dynamic is controlled by some factors and process such as habitat conditions, species composition, and regeneration and disturbance events. Given to role of Zagros forests in soil and water conservation, the present research was aimed to evaluate edaphicproperties of lands under mixed-and monoculture (cereals) system to non-cultivation in forest. Then, a short reconnaissance was conducted using global positioning system (GPS) to determine mixed and monoculture lands. In order to remove edge effects, a control site (non -cultivated in forest) was selected in a suitable distance taking physiographical factors (slope, aspect, sea level -above elevation)into account so that it was homogenized in respect to vegetation type, geology and so on compared to mixed and mono -cultured lands. Some statistical grids (12 50×800m2) were landed on study area digital maps using GIS (geographical information system). The number of fifteen rectangular 25×30 m plots was distributed in field by GPS. For every study site, soils samples were taken from depths 0-10, 10-20 cm and were transported to laboratory for analysis soil acidity by EC-meter, electrical conductivity by pH-meter, total calcium, organic carbon and matter according to titration method, soil texture by hydrometric method, phosphor by Olsen method, K by photometric film, soil moisture by weighting method, bulk density by coagulation and total nitrogen by Kejeldal one. Results showed that non-cultivated and mixed-cultured lands were superior to mono-cultured one in forest respectively. In respect to great contribution of Zagros forests in soil and water conservation, results obtained from the present research showed that any anthropological interference(such as planting native species) in this system, interrupts these forest natural balance. To conserve soil and water balance within such systems, mixed-culture of orchard species is more superior to mono-culturing (cereals).