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dc.contributor.authorZewdie W.
dc.contributor.authorCsaplovics E.
dc.contributor.authorInostroza L.
dc.date.accessioned2020-09-02T22:31:08Z
dc.date.available2020-09-02T22:31:08Z
dc.date.issued2017
dc.identifier10.1016/j.apgeog.2016.12.019
dc.identifier.citation79, , 167-178
dc.identifier.issn01436228
dc.identifier.urihttps://hdl.handle.net/20.500.12728/6733
dc.descriptionDryland ecosystems are highly vulnerable to environmental changes. Monitoring is vital in order to evaluate their response to fluctuating rainfall and temperature patterns for long-term ecosystem safeguarding. Monitoring of long term changes of normalized difference vegetation index (NDVI) and climate variables are fundamental for better understanding of change trajectories in dryland ecosystem, and to ascertain their potential interaction with anthropogenic drivers. In this study, we identify determinant factors of dryland changes by using MODIS NDVI, precipitation and temperature data for Breaks for Additive Seasonal and Trend (BFAST) and Mann Kendall test statistic. BFAST predicts iteratively time and number of changes within a time series data to depict the size and direction of changes. Analysis of NDVI, precipitation and temperature time series data showed substantial changes during the study period of 2000–2014. There is a reduction trend in vegetation showed by the decline in NDVI, with significant breakpoints till 2009 and recovery afterwards, without a significant change in annual trends of precipitation (α < 0.05) for the same study period. Furthermore 2 positive climate trends were founded: a) a significant positive trend on long term annual rainfall during the main rainy seasons and; 2) a significant (α < 0.05) annual increment of the long term mean minimum and mean maximum temperature of 0.03 °C/year and 0.04 °C/year, respectively. This assessment showed that climate variables cannot be considered as the main factors in explaining the observed patterns of vegetation dynamics. Seasonal and interannual precipitation changes have a lower weight as driving factors for the reduction in vegetation trends. Hence, the decline in vegetation productivity of the region can be attributed to the increasing pressure of human activities. © 2017 Elsevier Ltd
dc.language.isoen
dc.publisherElsevier Ltd
dc.subjectBFAST
dc.subjectDryland
dc.subjectMann-Kendall
dc.subjectNDVI
dc.subjectPrecipitation
dc.subjectTemperature
dc.subjectair temperature
dc.subjectclimate variation
dc.subjectecosystem dynamics
dc.subjectmonitoring
dc.subjectNDVI
dc.subjectprecipitation (climatology)
dc.subjecttime series
dc.subjectvegetation
dc.subjectEthiopia
dc.titleMonitoring ecosystem dynamics in northwestern Ethiopia using NDVI and climate variables to assess long term trends in dryland vegetation variability
dc.typeArticle


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