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Eastern Cape Province in South Africa has experienced extreme drought events during the last decade. In South Africa, different land management systems exist belonging to two different land tenure classes: commercial large scale farming and communal small-scale subsistence farming. Communal lands are often reported to be affected by land degradation and drought events among others considered as trigger for this process. Against this background, we analyzed vegetation response to drought in different land management and land tenure systems through assessing vegetation productivity trends and monitoring the intensity, frequency and distribution of the drought hazard in grasslands and communal and commercial croplands during drought and non-drought conditions.

Drought is one of the most severe natural disasters with a high risk for human livelihoods. Remote sensing based drought indices can identify dry periods using, e.g., precipitation or vegetation information. Besides frequency, duration, and intensity, the timing of a drought onset and duration are important variables to measure the drought impact and risk. This article classifies drought events based on the timing of the drought and with regard to their impact on vegetation production during different crop growing stages. Drought and nondrought seasons are analyzed in Eastern Cape Province, South Africa. Here, the impact of a drought on vegetation production highly depends on the starting point and the duration of rainfall during the growing season. Weighted linear combination was applied based on vulnerable vegetation growing stages in the phenology to classify drought severity per season. Particularly the extreme drought season in 2015/2016 as well as the normal nondrought season in 2011/2012 was emphasized. The developed approach serves as input to quantify drought impact per cropping season from local to regional scales. Integration of socioeconomic information can further complement this hazard information to support the quantification of the actual drought risk. Index Terms-Drought indices, phenology, risk analysis, time series analysis, weighted linear combination (WLC). I. INTRODUCTION D ROUGHT is one of the most severe disasters of the 21st century. It contributes to global food insecurity, environmental and economic problems, and ranks first with regard to the number of people affected due to natural hazards on a global scale [1], [2]. Droughts are naturally occurring but increased Manuscript