USESOME SOIL ANIMALS AS BIOINDICATORS OF SOIL HEALTH IRRIGATED WITH AGRICULTURAL DRAINAGE WATER

Abstract

Shortage in Nile water resources resulted in using the unconventional sources of water such as drainage water. The current study was carried out to determine health of soil irrigated with agricultural drainage water using soil animals as bioindicators under different cultivation periods (0, 3, 8, 12 and 18 years), irrigated through dripping water systemsand cultivated with Olive trees located at Kom Oshim area compared with a site irrigated with Nile water (basin irrigation) for more than 50 years ago and cultivated with alfaalfa crop located at Al Alaam area. The age of the Kom Oshim sites are: not cultivated (0years), three years, eight years, thirteen years and eighteen years. Irrigation water was mixed in a ratio of 3:1 (irrigation drainage water: Nile water) at the mixing station located on Kobry El Bayomy (North of Kom Oshim). Application of the mixed water for irrigation purposes since about eighteen years ago case changes in many of soil properties specially those are more affected by increase of soil salinity and alkalinity levels. Also Soil bulk density which showed a gradual increase with EC levels, while the decrease in drainable pores and soil permeability plays an important role for modifying the other physical properties in soil which leads to the degradation of soil aggregates.Samples were collected during 2012. Since soil health is strongly influenced by microbe-mediated processes, and function can be related to diversity, it is likely that microbial community structure will have the potential to serve as an early indication of soil degradation or soil improvement.Biomass, community structure, and specific functions of soil microorganisms appear to be of major importance for general soil functions and if detectable could serve as sensitive soil quality indicators. Key Words: El Fayoum soil, Soil degradation, Agricultural drainage water, Soil fauna, Soil Health.