تعيين مهم ترين ويژگي هاي خاكي مؤثر بر عملكرد برنج در شاليزار‌هاي شمال‌ غرب استان گيلان

Determining the Most Important Soil Properties Affecting Rice Yield in Paddy Fields of the Northwestern Guilan Province

برنج ﻧﻘﺶ ﻣﻬﻤﻲ ﺩﺭ ﺗﻐﺬﻳﻪ نيمي ﺍﺯ ﻣﺮﺩﻡ ﺟﻬﺎﻥ، ﺑـﻪﻭﻳﮋﻩ ﺳﺎﮐﻨﺎﻥ ﮐﺸﻮﺭﻫﺎﻱ ﺩﺭ ﺣﺎﻝ توسعه دارد. ﻣﻴﺰان ﻋﻨﺎﺻﺮ ﻣﻮﺟـﻮد در ﺧـﺎك و ويژگي­هاي ﻓﻴﺰﻳﻜـﻲ آن ﻧﻘـﺶ ﺗﻌﻴـﻴﻦ ﻛﻨﻨﺪه­اي در ﻋﻤﻠﻜﺮد برنج دارند. اﻳـﻦ ﭘـﮋوﻫﺶ در بخشي از شاليزارهاي استان گيلان ﺑﻪ ﻣﻨﻈﻮر ﺑﺮرﺳﻲ رواﺑﻂ ﺑﻴﻦ ﻋﻤﻠﻜـﺮد برنج ﺑﺎ ﺑﺮﺧﻲ از وﻳﮋﮔﻲﻫﺎي ﻓﻴﺰﻳﻜﻲ، ﺷﻴﻤﻴﺎﻳﻲ و زيستي ﺧﺎك و ﺗﻌﻴﻴﻦ ﺳﻬﻢ آن دﺳﺘﻪ از وﻳﮋﮔﻲﻫﺎ ﻛﻪ ﺑﻴﺸﺘﺮﻳﻦ ﺗأﺛﻴﺮ را ﺑﺮ ﻋﻤﻠﻜـﺮد دارﻧـﺪ، اجرا گرديد. در اﻳﻦ راستا ﺑﻪ ﻣﻨﻈﻮر ﺗﺨﻤﻴﻦ ﻋﻤﻠﻜﺮد از رﮔﺮﺳﻴﻮن ﮔﺎم ﺑﻪ ﮔﺎم استفاده شد. در اين روش ﻋﻤﻠﻜﺮد برنج ﺑﻪ ﻋﻨﻮان ﻣﺘﻐﻴﺮ واﺑﺴﺘﻪ و وﻳﮋﮔﻲﻫﺎي ﻓﻴﺰﻳﻜﻲ، ﺷﻴﻤﻴﺎﻳﻲ و زيستي ﺧﺎك ﺑـﻪ ﻋﻨـﻮان ﻣﺘﻐﻴـﺮ ﻣﺴـﺘﻘﻞ در ﻧﻈـﺮ ﮔﺮﻓﺘﻪ ﺷﺪﻧﺪ. ﻣﻘﺪار نيتروژن كل، رسانايي الكتريكي، فسفر قابل دسترس، ﻣﻴﺎﻧﮕﻴﻦ وزﻧـﻲ ﻗﻄـﺮ ﺧﺎﻛﺪاﻧـﻪﻫـﺎ و درصد سيلت ﺧﺎك ﺑﻪ ﻋﻨﻮان ﻣﻬﻢ‌ترين وﻳﮋﮔﻲﻫـﺎي ﺧـﺎﻛﻲ ﻣؤﺛﺮ ﺑﺮ ﻋﻤﻠﻜﺮد برنج معرفي شدند.

Rice plays an important role in feeding half of the world, especially those living in developing countries. The amount of minerals in soil and soil physical properties have determinative role in rice yield. This study was conducted to investigate the relationship between rice yield and some of the physical, chemical and biological soil properties in paddy fields of Guilan province and to determine the contribution of those which have the greatest impact on rice yield through stepwise regression procedure. The measured rice yield values set up as dependent variable and the physical, chemical and biological soil properties were considered as independent variables. The of soil total nitrogen, EC, available phosphorus, mean weight diameter (MWD) and the percentage of silt had the greatest impact on rice yield.