Environ Monit Assess (2011) 180:313–324 DOI 10.1007/s10661-010-1790-z An integrated approach for spatio-temporal variability analysis of wetlands: a case study of Abaya and Chamo lakes, Ethiopia N. Tibebu Kassawmar · K. Ram Mohan Rao · G. Lemlem Abraha Received: 6 February 2010 / Accepted: 9 November 2010 / Published online: 26 November 2010 © Springer Science+Business Media B.V. 2010 Abstract Starting with the intensification of ir- rigation activities in the beginning of 1980s in Abaya and Chamo lakes area, the decreasing water inflow to the lakes caused denudation of the wetlands. The ecological situation in the lake region changed significantly during last four decades. The lakes and associated wetlands change have been studied using Landsat MSS (1973), Landsat TM (1986), and Ladsat ETM (2000) satellite imagery. Along with satellite im- agery, other hydro-meteorological data were col- lected and hydro-meteorological data analyses were done to assess the variability of wetlands. This research work has succeeded in estimating spatio-temporal changes of wetlands for the reason these changes should be estimated and associated factors affecting the changes should be determined for the sustainable management of wetlands. N. Tibebu Kassawmar Institute of Technology, Ambo University, Ambo, Ethiopia K. Ram Mohan Rao (B ) Indian Institute of Remote Sensing (NRSC), Dehradun, 248001, India e-mail: rammohan@iirs.gov.in G. Lemlem Abraha Department of Earth Sciences, Addis Ababa University, Addis Ababa, Ethiopia From these data, lakes morphometric property es- timation at different time series and water balance analysis for both lakes were done. Wetlands are mapped from the TCT image and these maps are subject to change detection to see the temporal and spatial variability of the wetlands. Moreover, the lake-morphometric area and volume varia- tion have been studied. The result showed that between 1986 and 2000, a significant reduction has been observed but lesser than the previous decades (6.4 km 2 ). The identified reason behind this change is that the free settlement and shore- line cultivation of the wetlands causing the soil erosion and eventually adds the sediment to the wetlands. Keywords Wetlands · Spatial and temporal variability · Lake-morphometric change Introduction Wetland degradation can be considered as dev- astating since degraded wetlands could lose their ability to perform their valuable functions (Mitsch and Gosselink 2000). Loss of even small wetlands would have great environmental impacts and it is critical that the few remaining wetland resources shall be protected and conserved. However, the impacts of environmental changes on wetland