using the attraction model in remote sensing to evaluation of topographic wetness index (twi)

نویسندگان

مرضیه مکرم

عضو هیئت علمی، دانشکدۀ کشاورزی و منابع طبیعی داراب، دانشگاه شیراز مجید حجتی

کارشناسی ارشد سنجش از دور و سیستم اطلاعات جغرافیایی، دانشگاه تهران عبدالرسول زارعی

عضو هیئت علمی، گروه مهندسی منابع طبیعی (مرتع و آبخیزداری)، دانشکدۀ کشاورزی، دانشگاه فسا

چکیده

the objective of this study is evaluation of topographic wetness index (twi) using attraction model in northern of fars province. the first attraction model was used to enhance the spatial resolution of digital elevation model (dem). in this research to estimate of value of sub-pixels neighboring pixels, touching and quadrant neighboring models were used. after manufacturing output images for sub pixels in the 2, 3 and 4 scales with different neighborhoods, the best scale with most appropriate type of neighborhood was determined using ground control points then the values of rmse was calculated for them. the total number of ground control points extracted from the mapping maintenance was 2118 points. the results showed that between scales with different neighborhoods, 3 scale and quadrant neighboring model have the most accuracy by the lowest value of rmse for dem 90 meter. then using produced dem from 3 scale and quadrant neighboring model, topographic wetness index for the study area was determined. the results showed that topographic wetness index (twi) in the study area is variable between -4.45 to 6.06. central zones of the study area have the highest values ​​of wetness. compare of wetness index produced from attraction model (with more spatial resolution) with dem 90 meter (with lower spatial resolution) showed that with using attraction model, more details of the amount of moisture in the study area, is visible.

برای دانلود باید عضویت طلایی داشته باشید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

On the calculation of the topographic wetness index: evaluation of different methods based on field observations

The topographic wetness index (TWI, ln(a/tanβ)), which combines local upslope contributing area and slope, is commonly used to quantify topographic control on hydrological processes. Methods of computing this index differ primarily in the way the upslope contributing area is calculated. In this study we compared a number of calculation methods for TWI and evaluated them in terms of their correl...

متن کامل

the use of appropriate madm model for ranking the vendors of mci equipments using fuzzy approach

abstract nowadays, the science of decision making has been paid to more attention due to the complexity of the problems of suppliers selection. as known, one of the efficient tools in economic and human resources development is the extension of communication networks in developing countries. so, the proper selection of suppliers of tc equipments is of concern very much. in this study, a ...

15 صفحه اول

the effect of using model essays on the develpment of writing proficiency of iranina pre-intermediate efl learners

abstract the present study was conducted to investigate the effect of using model essays on the development of writing proficiency of iranian pre-intermediate efl learners. to fulfill the purpose of the study, 55 pre- intermediate learners of parsa language institute were chosen by means of administering proficiency test. based on the results of the pretest, two matched groups, one as the expe...

Evaluation of Land Use Changes order to Desertification Monitoring Using Remote Sensing Techniques

Introduction Trend of increasing natural resource degradation in many parts of the world, is a serious threat to humanity. Desertification is one of the manifestations of the damage that has already suffered as a scourge of many countries, including developing countries are. At present, remote sensing is one of technologies with timeliness data and accuracy suitable for monitoring land use c...

متن کامل

Topographic Wetness Index Computed Using Multiple Flow Direction Algorithm and Local Maximum Downslope Gradient

Topographic wetness index (TWI) can quantify the control of local topography on hydrological processes and indicate the spatial distribution of soil moisture and surface saturation. The formulation is TWI=ln(a/tanβ), where a is the upslope contributing area per unit contour length and β is the local gradient. Many of the existing flow-direction algorithms for computing a use global partition ex...

متن کامل

Evaluation of remote sensing indicators in drought monitoring using machine learning algorithms (Case study: Marivan city)

Remote sensing indices are used to analyze the Spatio-temporal distribution of drought conditions and to identify the severity of drought. This study, using various drought indices generated from Madis and TRMM satellite data extracted from Google Earth Engine (GEE) platform. Drought conditions in Marivan city from February to November for the years 2001 to 2017 were analyzed based on spatial a...

متن کامل

منابع من

با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید


عنوان ژورنال:
اکو هیدرولوژی

جلد ۴، شماره ۱، صفحات ۲۳۷-۲۴۵

میزبانی شده توسط پلتفرم ابری doprax.com

copyright © 2015-2023