الفهرس | Only 14 pages are availabe for public view |
Abstract Eicllltornia crassipes, a dominant cosmopolitan floating hydrophyte has been studied in six aquatic surfaces, two open channels; Bahr Shebien (BSN) and Kafr El-Zyat (KFZ), two streams; Kafr Essam (KFE) and Talla (TAL) at Tanta; two drains, Omar Bick El-Kebier (OBK) and Seberbey (SRB) at Sa~nrnanoud and Tanta respectively, representing the major irrigation and drain water courses in the Nile Delta region. Air temperature, relative humidity and wind speed, besides water transparency are the most important factors governing the growth of E. crassrjles. Differences have been found between the irrigation and drain water systems regarding electrical conductivity (EC), pH value, biological oxygen demand (BOD), chemical oxygen demand (COD) and mineral ion content reflecting also the growth of E. crussipes . Irrigation water being the most suitable source for collecting E. crussipes as it accu~nulates lower levels of heavy metals and trace elements and can be used for the reclamation of sandy soil with limited fertility. Mixing sandy soil wit11 E. crussipes alone or in combination with animal manure have improved its properties, including structure, texture, pore size, organic matter and nutrient contents as well as its water status. Upon the addition of E. crussrjles alone or in combination with animal manure, nutrients accumulated in the plant material have been released gradually and concurrently with the increase in soil water retention depending on the level applied. Ca2+, Kt, Mg2+, P and organic matter contents have been increased gradually with the level of soil additive, reaching their maximum with the highest level of the combined mixture. Soil water content of the improved sandy soil has been increased also where the highest percentage was reached with the combined mixture. Addition of E. crassipes has decreased evaporation from sandy soil exposed to 50•‹C. Soil treated with either fresh crushed, dry-powdered E. crussipes, animal manure or the combined mixture has been used for testing the growth parameters and the major metabolic products of barley (Horderrnz vulgu~eL. cv. Giza 124). |