title: Spatiotemporal variation of watershed health propensity through reliability-resilience-vulnerability based drought index (case study: Shazand Watershed in Iran).
abstract: Quantitative response of the watershed health to climate variability is of critical importance for watershed managers. However, existing studies seldom considered the impact of climate variability on watershed health. The present study therefore aimed to analyze the temporal and spatial variability of reliability (Rel), resilience (Res) and vulnerability (Vul) indicators in node years of 1986, 1998, 2008 and 2014 in connection with Standardized Precipitation Index (SPI) for 24 sub-watersheds in the Shazand Watershed of Markazi Province in Iran. The analysis was based on rainfall variability as one of the main climatic drivers. To achieve the study purposes, the monthly rainfall time series of eight rain gauge stations distributed across the watershed or neighboring areas were analyzed and corresponding SPIs and RelResVulindicators were calculated. Ultimately, the spatial variation of SPI oriented RelResVulwas mapped for the study watershed using Geographic Information System (GIS). The average and standard deviation of SPI-RelResVulindex for the study years of 1986, 1998, 2008 and 2014 was obtained 0.240±0.025, 0.290±0.036, 0.077±0.0280 and 0.241±0.081, respectively. In overall, the results of the study proved the spatiotemporal variations of SPI-RelResVulwatershed health index in the study area. Accordingly, all the sub-watersheds of the Shazand Watershed were grouped in unhealthy and very unhealthy conditions in all the study years. For 1986 and 1998 all the sub-watersheds were assessed in unhealthy status. Whilst, it declined to very unhealthy condition in 2008 and then some 75% of the watershed ultimately referred again to unhealthy and the rest still remained under very unhealthy conditions in 2014.
authors.affiliation: Department of Watershed Management Engineering, Faculty of Natural Resources, Tarbiat Modares University, Iran. Electronic address: sadeghi@modares.ac.ir.
authors.forename: Seyed Hamidreza
authors.initials: SH
authors.lastname: Sadeghi
authors.affiliation: Watershed Management Engineering, Faculty of Natural Resources, Tarbiat Modares University, Iran. Electronic address: z.hazbavi@modares.ac.ir.
authors.forename: Zeinab
authors.initials: Z
authors.lastname: Hazbavi
mesh_terms: D003247:Conservation of Natural Resources; D055864:Droughts; D017753:Ecosystem; D004784:Environmental Monitoring; D040362:Geographic Information Systems; D007492:Iran; D011891:Rain; D045483:Rivers; D012987:Soil; D014872:Water Movements
chemical_list: D012987:Soil
keywords: Adaptation strategy; Climate variability; Ecosystem health assessment; Environmental monitoring; Land degradation; Sustainable health