Procena hidroloških osobina suše: studija u oblasti basena Tamil Nadu u Indiji

Assessment of hydrological drought and evaluation of drought characteristics provide useful information for sustainable water resources planning and management in a river basin. In the present study, streamflow drought index (SDI) was used to assess the hydrological drought characteristics in the Parambikulam-Aliyar basin of Tamil Nadu, India by considering streamflow volume as an indicator of drought severity. The temporal behavior of hydrological droughts were analyzed initially and then, frequency of annual drought severity and recurrence patterns of severe drought events was assessed. The temporal analysis of the SDI values indicated that moderate, severe and extreme droughts are common in the Aliyar sub basin and suggested that the basin suffered severe drought during the 1970s, 1980s and 2000s especially in 1972-74, 1982-85, 1987-88 and 2002-04. January followed by June are the months during which hydrological drought occurs most frequently. Frequency analysis of drought severity indicated that the drought that occurred in the 1970s, 1980s and 2000s has an associated return period of about 80 to 100 years. The results of this study can be used as guide to develop drought preparedness plans and formulate mitigation measures within the basin.Procenom hidroloških osobina suše dolazi se do korisnih informacija koje su od značaja prilikom upravljanja vodnim resursima u rečnom basenu. U ovoj studiji su karakteristike suše u basenu Parambikulam-Aliyar u oblasti Tamil Nadu u Indiji, opisane indeksom strujanja (SDI - streamflow index) kao indikatorom intenziteta sušnog perioda. Analizirane su pojedinačne promene hodroloških karakteristika, njihova učestanost ponavljanja i mogućnost za predviđanje njihovih budućih vrednosti. Na osnovu dobijenih SDI vrednosti, napravljena je klasifikacija intenziteta suše i to kao: umerena, ozbiljna i ekstremna suša. Utvrđeno je da je analizirani basen u oblasti Tamil Nadu bio izložen ozbiljnim sušnim periodima tokom 1970-ih, 1980-ih i 2000-ih naročito u periodu 1972-74, 1982-85, 1987-88 i 2002-04. Hidrološke karakteristike suše su najnepovoljnije u mesecu Januaru i mesecu Junu. Utvrđena je učestanost ponavljanja ozbiljnih sušnih perioda na svakih 80 do 100 godina. Rezultati uve studije se mogu iskoristiti prilikom planiranja mera zaštite od suša u basenu