Environmental Flow And Recommendations For Their Estimations

Abstract

689 the quantity of water, but also a condition of the river system, which can safely maintain all ecologic needs in the ecosystem. For quarantines the necessary conditions, there are a need in many physical, chemical and biological characteristics, mainly in sufficient quantity, quality, temperature and flow rate. In spite of the fact, that researchers are engaged in research of ecological flow since 1940s, up to this point there was not accepted the standardized term, for impression of the “ecological flow”. Therefore, instead of the term" ecological flow”, various terms are used by a variety of researchers, such as:“sanitary river flow”,“instream flow”,“stream flow”,“reserved flow”,“minimally residual runoff”,“minimally acceptable flow”,“minimally nessesary flow”,“environmental flow” etc.(Gatillo and Filipovich, 1971; Tenant, 1975; Shahov, 1980; Smatkhin et al., 2006 est.). In some cases researchers instead of ecological flow investigated the “base flow”, mainly supplied on ground-water discharge is considered as a base ecological maintenance of the river ecosystem (Jonathan and Mark, 2002). Although for investigation of “ecological flow” are used different approaches as well as different terms, in almost all cases “ecological flow” means some quantity of water which must be remained in riverbeds for satisfying some economic and environmental needs. However, in some cases, ecological flow is not only the minimum amount of water, but also maximum limit of river flow for satisfying fishery needs, and for that purpose used a term “ecological high flow”(Lin et al., 2006). Fashevskiy and Fashevskaya (2003) consider that the term should be used as an …