Evaluation of the Nutrient Status of Some Hydrophytes in the Water Courses of Nile Delta, Egypt

[摘要] The nutritive values of three dominant hydrophytes along the water courses in Nile Delta, Egypt (Echinochloa stagnina,Eichhornia crassipes, andCeratophyllum demersum) were evaluated in terms of estimating their phytomass, organic, and inorganic chemical compositions. Shoots were collected seasonally from 25 permanent stands representing the distribution of the three species along 15 canals and 10 drains distributed in 5 localities within the Nile Delta. Living and dead parts and total phytomass were estimated. Their inorganic (Na, K, Ca, Mg, P, Cu, Mn, and Pb) and organic (carbohydrates, total nitrogen, total protein, ether extract, digestible nutrient, digestible energy, metabolized energy, and net energy) contents were estimated. The vegetative phase ofE. stagninaextended during winter, spring, and summer, while it is flowering and fruiting during autumn. On the other hand,E. crassipesandC. demersumattained their maximum flowering during spring and maximum fruiting during summer, while maximum vegetative phase during autumn and winter.E. stagninahad the highest mean annual phytomass, whileC. demersumhad the lowest. The living parts ofC. demersumhad the highest concentrations of Na, Ca, and Mg, while the living parts ofE. crassipeshad the highest of K and N.C. demersumhad the ability to accumulate more concentrations of heavy metals than the other studied species.E. crassipeshad the highest values of total carbohydrate and total proteins, whileE. stagninahad the highest of crude fibers, andC. demersumhad the highest of ether extract and ash contents. The living parts ofE. crassipesandC. demersumwere considered as excellent forages, while the dead parts of all species and the living parts ofE. stagninawere evaluated as poor forage.

[学科分类] 植物学