Large-scale fluvial landforms emerge from iterative processes that sculpt Earth's surface. Tectonics, climate variability and erosion are major recurrent processes reshaping fluvial landforms ending up in self-affine patterns. In the case of the Pantanal, the largest wetland in South America, its depositional tract can be subdivided as fluvial megafans, interfans and the main trunk system. Here we provide an outlook of their origins by means of self-affine landforms and on the feedback of climate changes over landform functionalities. Climate variability modulates the magnitude of interannual fluvial discharge and sediment load from highlands to plains, affects groundwater recharge, as well as the subsidence and generation of accommodation in the depositional tract through river avulsion. Scenarios are envisaged by analyzing long-term summer rainfall intensity and the number of dry days in autumn/winter over the Upper Paraguay River Basin, and annual flood peaks measured at fluvial gauge stations in the Paraguay River at Ladário (Brazil) and Asunción (Paraguay). The frequency distributions of the annual flood peaks are found unimodal for Asunción and bimodal for Ladário, which suggests an unknown water supply at Asunción, likely from Pilcomayo River and Pantanal's groundwater. The latter might play a delayed role on Pantanal's hydrologic functioning at 20–40 years timescales. Besides the Paraguay River flood peaks, summer rainfall intensity and the number of dry days in autumn/winter are quasi-periodic at interannual and decadal scales. Cross-correlations analyses indicate a long-range memory between river floods and rainfall intensity, and 15–20 years lag between river floods and the number of dry days in drought seasons. Trends analysis suggests that summer rainfall intensity and the number of dry days in autumn/winter have been consistently increasing by about 0.6 mm/day/decade and 1 day/decade, respectively. Therefore, magnifications of fluvial discharge and sediment load at wet seasons and water deficits at drought seasons are anticipated. Such a scenario indicates extreme dry cycles over all self-affine functional landforms, particularly on abandoned lobes relying exclusively on rainwater, whereas extremes of rainfall intensity at rivers headwaters may amplify the risks of large-scale avulsions at active lobes of the fluvial megafans. In contrast, active lobes of megafans, interfans and the main trunk river system emerge as hotpots for wildlife refuge and ecosystem services.

大规模的河流地貌来自于塑造地球表面的迭代过程。构造、气候变化和侵蚀是重塑河流地貌的主要反复过程，最终形成自仿射模式。以南美洲最大湿地潘塔纳尔湿地为例，其沉积域可细分为河流巨扇、间扇和主干系统。在这里，我们通过自仿射地貌和气候变化对地貌功能的反馈来提供对其起源的展望。气候变率调节年际河流排放量和从高原到平原的沉积物负荷，影响地下水补给，以及通过河流撕脱在沉积域中沉降和产生住宿。通过分析长期夏季降雨强度来设想情景以及巴拉圭河流域上游秋季/冬季的干旱天数，以及在拉达里奥（巴西）和亚松森（巴拉圭）巴拉圭河的河流测量站测量的年度洪水高峰。亚松森的年度洪水高峰频率分布是单峰的，而拉达里奥的则是双峰的，这表明亚松森的供水未知，可能来自皮尔科马约河和潘塔纳尔的地下水。后者可能在 20-40 年的时间尺度上对潘塔纳尔的水文功能起到延迟作用。除巴拉圭河洪峰外，夏季降雨强度和秋冬季干旱日数在年际和年代际尺度上呈准周期性。互相关分析表明河流洪水和降雨强度之间存在长期记忆，河流洪水与干旱季节的干旱天数之间存在 15-20 年的滞后。趋势分析表明，夏季降雨强度和秋季/冬季干旱天数分别持续增加约 0.6 毫米/天/十年和 1 天/十年。因此，预计雨季河流流量和沉积物负荷以及旱季缺水会放大。这种情况表明所有自仿射功能地貌的极端干旱循环，特别是在完全依赖雨水的废弃裂片上，而河流源头的极端降雨强度可能会放大河流巨扇活动裂片大规模撕脱的风险。相比之下，巨型风扇的活动叶，