برآورد پتانسیل‌های بیوفیزیکال در محدوده شبکه آبیاری و زهکشی دشت قزوین با استفاده از مدل‌های گیاهی DSSAT

نویسندگان

چکیده

در این پژوهش،‏ پتانسیل‌های بیوفیزیکال محصولات زراعی در محدوده اراضی شبکه آبیاری و زهکشی دشت قزوین ارزیابی شد. پس از ترسیم واحدهای اراضی،‏ شبیه‌سازی رشد و تولید محصولات زراعی مورد بررسی با مدل‌های گیاهی بسته نرم‌افزاری DSSAT انجام شد. در این شبیه‌سازی برای هر محصول،‏ دو رژیم آبیاری (معرف آبیاری سطحی و تحت‌فشار) به همراه 2 تا 3 تاریخ کشت مختلف در نظر گرفته شد. تحلیل نتایج نشان از تفاوت عملکرد محصولات در تیمارهای مختلف تاریخ کشت و رژیم‌های آبیاری بود. در بین محصولات عمده منطقه،‏ مقدار ضریب تغییرات مکانی گندم و جو در سطح متوسط قرار دارد،‏ در حالیکه محصول ذرت دانه‌ای دارای مقدار کوچک‌تر ضریب تغییرات است. در ارتباط با محصولاتی مانند گوجه‌فرنگی،‏ پنبه و سویا،‏ اختلاف زیادی بین عملکرد محصول در واحدهای مختلف اراضی وجود دارد و این مسأله باید در تعیین الگوی کشت این مناطق مورد توجه قرار گیرد. شاخص ضریب تغییرات زمانی محصولات نیز می‌تواند به عنوان شاخصی از ریسک موجود در ارتباط با کاشت این محصولات مورد توجه قرار گیرد. نتایج این بررسی،‏ اطلاعات ورودی لازم برای یک مدل پشتیبان برنامه‌ریزی مکانی را فراهم می‌کند.

کلیدواژه‌ها


عنوان مقاله [English]

Estimating biophysical potentials in Qazvin irrigation and drainage network using DSSAT crop models

نویسندگان [English]

  • Behnam Ababaei
  • Farhad Mirzaei
  • Teymour Sohrabi
چکیده [English]

In this research, the biophysical potentials of agricultural crops were analyzed in Qazvin irrigation and drainage network using DSSAT crop models. These models were calibrated and validated using field data or proper input coefficients were selected for the crops without such data. Land Units (LUs) were extracted by overlaying soil mapping units (SMUs) and weather grids using GIS. Weather grids were mapped using Thiessen method assuming each unit as a homogeneous area. Crop growth simulation was carried out using the DSSAT crop models. For each crop, two irrigation regimes (surface and pressurized) and 2-3 planting dates were considered. The results revealed the difference of crop production for each planting date and irrigation regime. Among the major crops in the study area, the values of spatial coefficient of variation were mediocre for Wheat and Barley, but lower for Corn. In relation to Tomato, Soybean and Cotton, significant differences were found between LUs and this issue must be taken in consideration when determining cropping pattern. The index of time coefficient of variation can also be used as a measure of risk in relation to the studied crops. The results of this research can be used as inputs of a spatial planning support system (PSS).In this research, the biophysical potentials of agricultural crops were analyzed in Qazvin irrigation and drainage network using DSSAT crop models. These models were calibrated and validated using field data or proper input coefficients were selected for the crops without such data. Land Units (LUs) were extracted by overlaying soil mapping units (SMUs) and weather grids using GIS. Weather grids were mapped using Thiessen method assuming each unit as a homogeneous area. Crop growth simulation was carried out using the DSSAT crop models. For each crop, two irrigation regimes (surface and pressurized) and 2-3 planting dates were considered. The results revealed the difference of crop production for each planting date and irrigation regime. Among the major crops in the study area, the values of spatial coefficient of variation were mediocre for Wheat and Barley, but lower for Corn. In relation to Tomato, Soybean and Cotton, significant differences were found between LUs and this issue must be taken in consideration when determining cropping pattern. The index of time coefficient of variation can also be used as a measure of risk in relation to the studied crops. The results of this research can be used as inputs of a spatial planning support system (PSS).In this research, the biophysical potentials of agricultural crops were analyzed in Qazvin irrigation and drainage network using DSSAT crop models. These models were calibrated and validated using field data or proper input coefficients were selected for the crops without such data. Land Units (LUs) were extracted by overlaying soil mapping units (SMUs) and weather grids using GIS. Weather grids were mapped using Thiessen method assuming each unit as a homogeneous area. Crop growth simulation was carried out using the DSSAT crop models. For each crop, two irrigation regimes (surface and pressurized) and 2-3 planting dates were considered. The results revealed the difference of crop production for each planting date and irrigation regime. Among the major crops in the study area, the values of spatial coefficient of variation were mediocre for Wheat and Barley, but lower for Corn. In relation to Tomato, Soybean and Cotton, significant differences were found between LUs and this issue must be taken in consideration when determining cropping pattern. The index of time coefficient of variation can also be used as a measure of risk in relation to the studied crops. The results of this research can be used as inputs of a spatial planning support system (PSS).In this research, the biophysical potentials of agricultural crops were analyzed in Qazvin irrigation and drainage network using DSSAT crop models. These models were calibrated and validated using field data or proper input coefficients were selected for the crops without such data. Land Units (LUs) were extracted by overlaying soil mapping units (SMUs) and weather grids using GIS. Weather grids were mapped using Thiessen method assuming each unit as a homogeneous area. Crop growth simulation was carried out using the DSSAT crop models. For each crop, two irrigation regimes (surface and pressurized) and 2-3 planting dates were considered. The results revealed the difference of crop production for each planting date and irrigation regime. Among the major crops in the study area, the values of spatial coefficient of variation were mediocre for Wheat and Barley, but lower for Corn. In relation to Tomato, Soybean and Cotton, significant differences were found between LUs and this issue must be taken in consideration when determining cropping pattern. The index of time coefficient of variation can also be used as a measure of risk in relation to the studied crops. The results of this research can be used as inputs of a spatial planning support system (PSS).

کلیدواژه‌ها [English]

  • Simulation.-Land units-Planning-Iran-risk-