A study of vegetation in Sistan region through satellite data
Subject Areas : Journal of Plant Ecophysiology
H.
Shafei
1
(کارشناس ارشد بیابان زدایی، دانشکده منابع طبیعی، دانشگاه زابل)
S. M.
Hosseini
2
(کارشناس ارشد بیابان زدایی و عضو باشگاه پژوهشگران جوان دانشگاه آزاد اسلامی واحد ارسنجان)
Keywords:
Abstract :
Desertification means land degradation in arid, semi-arid, and semi-humid areas, which happens due to changes in climatic conditions and human activities. Sistan plain is a dry area in the eastern part of Iranthat is suffering from desertification as the main problem. The main purpose of this two-year study is to assess changes in the vegetation of the region within the time period from1990 to 2006. Field sampling, satellite images, and related software were used to conduct the present study. First of all, field sampling method was randomly and systematically performed in 26 well-known sites. For each site, nine 10×10 m plots were recorded. In the next stage, the required processes were conducted on the satellite images and vegetation indices were generated. Correlation analysis was performed between data related to land coverings and spectral values of corresponding pixels. The highest correlations obtained among 83 estimated indicators were related to indices of WDVI, NDVIab, TSAVI2 and MSAVI1, respectively. The obtained images were classified into two coverage and non-coverage groups. Then the precision of plots were evaluated and the highest precision of 83.27% was related to the plot taken for WDVI which had the highest correlation coefficient (p<0.01 and R2 =0.89) as well. Based on these plots, vegetation rate was determined as 101247 acre for 1990 which decreased to 26475 acres for 2006. ایج این آزمایش نشان داد در شرایط شور استفاه از رقم اکبری و بذرمالی+محلولپاشی اسید سالیسیلیک مناسبترین تیمار جهت حصول عملکرد مطلوب بود. م در هکتار بیشترین وزن تر را داشت. در بین الگوهای کاشت مورد مطالعه، الگوی کاشت یک طرفه بیشترین وزن تر را با 13519 کیلوگرم در هکتار و بیشترین میزان بیوماس را با 7200 کیلوگرم در هکتار به خود اختصاص داد. در بین تراکم های آزمایش شده، بیشترین وزن تر با 13084 کیلوگرم در هکتار، بیشترین میزان بیوماس با 44/2467 کیلوگرم در هکتار و بیشترین تعداد میوه با 4/13450 میوه از تراکم 80000 بوته در هکتار بدست آمد.
