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Understanding the canopy cover relationship with canopy water content and canopy temperature in the Miombo ecosystem is important for studying the consequences of climate change. To better understand these relationships, we studied the satellite data-based land surface temperature (LST) as proxy for canopy temperature, leaf area index (LAI), and the normalized difference vegetation index (NDVI) as proxies for canopy cover. Meanwhile, the normalized difference infrared index (NDII) was used as a proxy for canopy water content. We used several statistical approaches including the correlated component regression linear model (CCR.LM) to understand the relationships. Our results showed that the most determinant factor of variations in the canopy cover was the interaction between canopy water content (i.e., NDII) and canopy temperature (i.e., LST) with coefficients of determination (R2) ranging between 0.67 and 0.96. However, the coefficients of estimates showed the canopy water content (i.e., NDII) to have had the largest percentage of the interactive effect on the variations in canopy cover regardless of the proxy used i.e., LAI or NDVI. From 2009–2018, the NDII (proxy for canopy water content) showed no significant (at alpha level 0.05) trend. However, there was a-n significant upward trend in LST (proxy for canopy temperature) with a magnitude of 0.17 °C/year. Yet, the upward trend in LST did not result in significant (at alpha level 0.05) downward changes in canopy cover (i.e., proxied by LAI and NDVI). This result augments the observed least determinant factor characterization of temperature (i.e., LST) on the variations in canopy cover as compared to the vegetation water content (i.e., NDII).

Semi-arid catchments under change: Adapted hydrological models to simulate the influence of climate change and human activities on rainfall-runoff processes in southern Africa. In: Climate change and adaptive land management in southern Africa -assessments, changes, challenges, and solutions (ed. by Water resources 114C A Abstract: A comprehensive river basin assessment is key to integrated land and water resources management (ILWRM), which is based on an integrated system analysis to identify interacting hydrological processes that are driven by landscape features and socioeconomic development. Software toolsets like RBIS (River Basin Information System), GRASS-HRU, and the hydrological modelling system JAMS/J2000 were used and further developed for basin assessments and modelling of hydrological process dynamics and other environmental processes in selected catchments in southern Africa. These are the Gaborone Dam catchment (Botswana, South Africa), the Verlorenvlei catchment (South Africa), and the Luanginga catchment (Angola, Zambia). All of these catchments respond very sensitively to changes in climate and land management, revealing additional issues like a strong decline of infl ow (Gaborone Dam) or a decline of usable groundwater resources (Verlorenvlei). Further, extensive wetland areas in the Upper Zambezi (Luanginga) respond strongly to changes in hydroclimatic conditions and land management. In this study, newly developed and improved simulation components for representing processes with a strong local impact on the hydrological conditions such as fl oodplain inundation, irrigation, small farm dams, and contour bank farming were used to more precisely simulate the hydrology of the respective basins. After successful model validation and an improved understanding of catchment dynamics, the models were used as a platform for diff erent land or climate change analysis. Taking the RCP 8.5 scenario based on EC-Earth and ECHAM, downscaled by REMO, into account, the Luanginga catchment showed a strong decrease in runoff generation, inundation extent, and groundwater recharge. For the Kruismannsrivier, a sub-catchment of the Verlorenvlei, the relation between contour farming and related eff ects on surface/subsurface runoff processes and related parameters were revealed through modelling. These fi ndings could also be projected to the Gaborone Dam catchment, in which the infl uence of small farm dams spread over the catchment could be shown by modelling.Resumo: Uma avaliação abrangente da bacia hidrográfi ca é essencial para a gestão integrada dos recursos terrestres e hí-dricos (ILWRM), a qual é baseada numa análise integrada do sistema para identifi car processos hidrológicos em interacção que são impulsionados pelas características da paisagem e o desenvolvimento socioeconómico. Ferramentas de software, tais como RBIS (River Basin Information System), GRASS-HRU e o sistema de modelação hidrológica JAMS/J2000,foram utilizadas e desenvolvidas para avaliações de bacias e modelação de dinâmicas de processo...

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