تاثير غلظت هاي متفاوت اسيد استيك بر قابليت رها سازي پتاسيم ميكاهاي دي و تري اكتاهدرال در محيط ريشه ي چمن

چكيده انگليسي :

Effect of Different Concentrations of Acetic Acid on K Release from Di and Tri octahedral Micas in Turf Grass Poa pratensis Root Zone Ensiyeh Mazaheri Mehr e mazaherimehr@ag iut ac ir Date of Submission January 22 2013 Department of Soil Science College of Agriculture Isfahan University of Technology Isfahan 84156 83111 Iran Degree M Sc Language Farsi Supervisor Hossein Khademi hkhademi@cc iut ac ir Abstract Low molecular weight organic acids which are produced during various chemical and biological processes in soil play key roles in many soil processes such as mobility and availability of nutrients and mineral weathering The rate of non exchangeable potassium release from minerals can profoundly affect the soil fertility Considering the relatively high concentration of acetic acid in root exudates the objective of this study was to evaluate the effects of added different concentrations of acetic acid to the rhizosphere on the likely increase of the amount and rate of K release from phlogopite and muscovite A pot experiment was carried out under green house conditions for a period of 322 days using a completely randomized design with factorial arrangement and 3 replications Treatments consisted of 4 concentrations of acetic acid 0 0 001 0 01 and 0 05 M 3 types of growth media phlogopite quartz sand cocopeat muscovite quartz sand cocopeat and quartz sand cocopeat as control and 2 types of nutrient solutions complete and K free During the experiment plants grass were irrigated with distilled water as well as nutrient and acetic acid solutions as necessary During the growth period plant shoot was harvested a few times and at the end of the experiment both shoot and root were harvested The K content of the plant samples was measured by a flame photometer Also the mineralogy of the silt fraction of the growth media was determined using an X ray diffractometer The results indicated the statistically significant influence of growth medium and nutrient solution on dry biomass and the K concentration and uptake The addition of 0 001 M acetic acid solution to the growth medium of plants treated with phlogopite and the K free nutrient solution could significantly increase the total K uptake of plant shoots In contrast both shoots and roots of the plants treated with 0 05 M acetic acid solution were damaged Dry shoot and root biomass of plants grown in phlogopite media treated with the K free nutrient solution were almost the same as those which received complete nutrient solution Under the K free nutrient solution plant biomass and K concentration and uptake in pots containing phlogopite were significantly higher than those having muscovite Phlogopite as a tri octahedral mica could sufficiently provide K for plants Under the K free nutrient solution and in all the acetic acid treatments the K concentrations of both shoot and roots of plants grown in muscovite containing media were not significantly higher than those in quartz sand media Whereas the shoot and root dry weights of plants treated with muscovite were significantly higher than those of control The mineralogical investigation indicated that silt sized phlogopite was transformed into vermiculite and mica vermiculite mineral as a result of interaction with both plants and added acetic acid The mineralogical changes in phlogopite was highest under 0 01 M acetic acid followed by 0 001 0 05 and 0 M concentrations The rate of mineralogical changes increased as the cetic acid concentration increase up to 0 001 M and then decreased due to damages caused to plants In conclusion in greenhouse conditions and for controlled and small plots such as the soccer fields and parks it is recommended to use phlogopite as a K bearing mineral along with a very diluted acetic acid solution instead of chemical fertilizers Keywords Organic acids acetic acid phlogopite muscovite mineralogy

مظاهري مهر، انسيه

تاثير غلظت هاي متفاوت اسيد استيك بر قابليت رها سازي پتاسيم ميكاهاي دي و تري اكتاهدرال در محيط ريشه ي چمن

اسيدهاي آلي , فلوگپيت , مسكويت , كاني شناسي