Publications

Darwish, DH; Basiony, AI; El-Alfy, MA (2021). Modeling and mapping trophic factors at deltaic Mediterranean Sea coast in Egypt using satellite imageries and statistical analyses. ARABIAN JOURNAL OF GEOSCIENCES, 14(21), 2205.

Abstract
This study is for estimation of the trophic levels based on laboratory data and integration of both Landsat OLI8 and Sentinel-2B imageries. Geo-referenced twelve water samples were collected along the deltaic Mediterranean coast. The analysis of nutrients (NH4, PO4, and NO2), DO, and chlorophyll a was done. Two important indices, namely, Carlson trophic state index CTSI and TRIX index, were used for estimation of trophic levels from analyzed lab data. According to CTSI, the area was categorized into oligotrophic and mesotrophic levels. While it was categorized into oligotrophic conditions according to the TRIX index based on the lab data. The study indicated that integration of Sentinel-2B (S2B) is more efficient than those of Landsat OLI8 (LS8) and MODIS/Aqua, which may be attributed to the high resolution of S2B. This was indicated from the statistical regression equations which give high significance between S2B followed by LS8 (P = 0.0008 for S2B and P = 0.015, respectively). Also, these equations give convergent values of P value in the case of estimation of phosphate from imageries (P varied between 0.026 and 0.036 for LS8 and S2B, respectively). The other two important used indices (floating algal index FAI and phytoplankton turbidity index PTI) were used to indicate the presence of macroalgae and phytoplankton turbidity in the study area. Finally, in addition to in situ and lab observations, using satellite images' data add much information in the interpretation of environmental problems of coastal areas like trophic conditions appear in different seasons.

DOI:
10.1007/s12517-021-08650-7

ISSN:
1866-7511