طراحي، ساخت و ارزيابي خاك ورز نواري جهت كشت محصولات رديفي

چكيده انگليسي :

Design Development and Evaluation of Strip Tillage Implements for Row Crop Production Javad Mohammadi JM33073@gmail com February 13 2012 Department of Agriculture Machinery Engineering College of Agriculture Isfahan University of Technology 84156 83111 IranDegree M Sc Language FarsiSupervisors Prof A Hemmat ahemmat@cc iut ac ir A Esehaghbeygi Esehaghbeygi@cc iut ac ir Abstract Protection of the soil against wind and water erosion is inevitable Conservation tillage is definedas any tillage and seeding system that maintains a minimum of 30 percent surface residue cover on thesoil surface after planting to reduce soil erosion by water or wind In addition to economic benefits of theconservation tillage systems increase in soil organic matter and fertility and moisture conservation canbe mentioned The disadvantages of this system are related to the cost of tillage equipment fightingweeds and emerging plants from the seeds of the previous crop Recently no tillage has been introducedas a conservation tillage system in central Iran with mixed results The main problem reported with no tillin the soils with low structural stability is poor crop establishment in high residue condition Strip tillageis an alternate way to improve crop establishment in such conditions In the strip tillage system a narrowwidth of soil where the seeds are planted is shallowly tilled while the residues between the crop rows areleft undisturbed The main objective of the research was to design develop and evaluate combined striptillage implements that make a loosened soil layer with a width and depth of 150 and 100 mm respectively in one pass The strip tillage implement was consisted of four units a a row cleaner b two side cutting disks c a strip tillage tool and d a roll packer Four types of strip tillage implementbased on the geometrical shape of its strip tillage tool were developed These implements were striptillage implement with i rigid shank equipped with triangular share ii bi level rigid shank equippedwith triangular share iii double bent blade subsurface tillage tool and iv two rippled disks In thisstudy the effect of these strip tillage implements working in three residue levels no residue standingresidue and high residue conditions and at two water contents 0 7 and 0 9 plastic limit on row cleaningperformance soil strength cross sectional area of the disturbed soil clod mean weight diameter MWD percentage of seed emergence plant establishment and dry matter accumulation in plants were studied The experiment was conducted in a clay loam soil at the Isfahan University Technology Research Farm Strip tillage machine with bi level rigid shank equipped with triangular share has the lowest soil strengthand the smallest clod mean weight diameter MWD and created the most appropriate tilled strip shape The benefit of strip tillage machine with bi level rigid shank equipped with triangular share was that itdoes not need to use side cutting disks for limiting the width of disturbed soil and so the number of unitsused in this type of strip tillage machine was lower There was no significant difference in percentage ofemergence and plant establishment among the three levels of residue and indicates that strip tillageimplements worked well in all residue conditions The results showed that in addition to having benefitof conservation tillage the stripe tillage system can have acceptable plant establishment in arid and semi arid areas of central Iran The advantages of the strip tillage machine with bi level rigid shank equippedwith triangular share can be recommended as a conservation tillage system for these areas Keywords Conservation tillage Strip tillage Surface tillage clod mean weightdiameter Plant establishment

محمدي، جواد

طراحي، ساخت و ارزيابي خاك ورز نواري جهت كشت محصولات رديفي

خاك ورزي حفاظتي , نوار خاك ورز , قطر متوسط وزني كلوخه