Characteristic trends in landuse and climate highlight critical challenges in future resource management along the tropical topoclimosequence (TCS) of the Rungwe Volcanic Province (RVP), a major headwater biodiversity and food reservoir of Tanzania. TheRVPorography supports a coherent distribution of agroecosystems and livelihoods, from hot irrigated lowlands to endangered afromontane forests above 1500 m.a.s.l. Recent increases in deforestation, land fragmentation and soil denudation/compaction in the densely populated TCS were combinedwith a strengthenedneedandconsumption ofwaterin the lower, warmer and drier end-member. Consistent with a regional decline of the long rains, a considerable (up to 30%) decrease in annual rainfall and a pervasive decline of the Lake Masoko (LM) aquifer testifies to a strong aridification trend. We suggest here that current landuse and demographic trends likely amplified the hydrological response of the TCS to regional and global warming. Testing such a hypothesis, however, requires improved local monitoring, to allow scaling and quantification of local hydrological budgets associated with landuse impacts, and evaluationofthecontributionoftreesandagroforestrysystemsto mitigating the aridification trend.