GIS-based spatial analysis: basic sanitation services in Parana State, Southern Brazil.

The objective of this study is to provide a view of the geographic distribution of basic sanitation services offered in Parana, Brazil. Temporal distributions, spatial patterns, and clusters were determined using 2000, 2010, and 2016 data. Tabular data of the percentages of households receiving water supply, waste collection, and sanitary sewage treatments were used as the basic inputs of the study. Time series maps were created using geographic information systems (GIS) for the visualization of the temporal changes in basic sanitation rates. The spatial variation in sanitation services was measured using Moran's Global Index (Moran's I), while the Local Indicators of Spatial Association (LISA) and Getis-Ord Gi*(d) were used to identify the presence of possible clusters and hot spots in the percentage of households with sanitation services. The study showed strong evidence that the service rates for sanitary sewage were significantly lower than those for water supply and waste collection. Waste collection proved to have the highest service rate in the study area. Waste collection was also the service that increased the most in the study period, followed by the water supply service. Identification of the most vulnerable municipalities was performed using LISA and the local Getis-Ord Gi*(d) statistic. Most of the low value clusters and cold spots were detected in the southern and west-central regions, while the high value hot spots and clusters were detected in the northern and northeastern regions of the state of Parana.