A sediment compartment approach is an appropriate framework within which to undertake planning and management of coastal environments, and a hierarchical scheme has been adopted by several state governments in Australia. This study applies a geospatial comparison of terrain modelling to estimate decadal-scale sediment transfer in a closed wave-dominated coastal compartment in southeastern Australia. The Shoalhaven River, one of the larger rivers in southern New South Wales, drains from a temperate catchment of 7151 km² into Shoalhaven Bight, a secondary compartment. The river has infilled the barrier estuary at its mouth in recent millennia, and delivers sediment that nourishes a well-developed strandplain to its north. We estimate sediment yield from the heterogeneous catchment based on deposition between 2003 and 2014 bathymetric surveys in a reservoir formed as a result of dam construction. Delivery of ~86,000 m³/y to the estuarine channel was calculated, adopting a known trap efficiency at the dam, augmented by sediment from a further unmodified tributary. Volumetric change of the estuary and adjacent nearshore was determined by comparison of surveys in 1981 and 2006. A complex pattern of estuarine surficial sediments reflects modification of the river's natural course, which is now artificially diverted to exit at Crookhaven Heads. During major flood events, the river intermittently discharges material to the shoreface at Shoalhaven Heads, its former mouth, which is impounded again by deposition of a sandy berm in the months following such storms. Between 1981 and 2006, at least 1,020,000 m³ was added to the estuary, and 1,065,000 m³ of sand was discharged to the shoreface. Sand sourced from the Shoalhaven River is retained within the northernmost of three tertiary compartments, Seven Mile Beach, as cliffed headlands and rocky reefs restrict along-shore sediment contributions from the south and inhibit leakage to the north. Balance of the budget based on shoreline accretion during 41 years is consistent with cross-shore transport and an ongoing shoreface supply rate of 1–2 m³/m/y. Although a number of uncertainties constrain the final sediment budget, with complex patterns of erosion or accretion in response to natural events or engineering interventions, this preliminary study indicates the potential for deriving decadal-scale estimates of sediment pathways and transfer rates using geospatial analysis of terrain changes, which can provide a basis for planning and management actions.

沉积物隔室方法是进行沿海环境规划和管理的适当框架，澳大利亚的几个州政府已采用分级方案。本研究应用地形模型的地理空间比较来估计澳大利亚东南部封闭的波浪主导的沿海隔间中的年代际沉积物转移。Shoalhaven 河是新南威尔士州南部较大的河流之一，从 7151 公里²的温带集水区流出进入Shoalhaven Bight，一个二级隔间。近千年来，这条河填满了河口的屏障河口，并输送了沉积物，滋养了其北部发育良好的滨海平原。我们根据 2003 年至 2014 年间因水坝建设而形成的水库中的水深调查的沉积物估算了异质流域的沉积物产量。~86,000 m ^{3 的}交付量计算到河口河道的 /y，在大坝采用已知的圈闭效率，并通过来自进一步未修改支流的沉积物增加。河口和邻近近岸的体积变化是通过比较 1981 年和 2006 年的调查确定的。河口表层沉积物的复杂模式反映了河流自然河道的改变，现在人为地将其改道到克鲁克海文角出口。在发生重大洪水事件时，河流间歇性地将物质排放到 Shoalhaven Heads 的岸面，即它的前河口，在此类风暴发生后的几个月里，该河口再次被沙质护堤淤积。1981 年至 2006 年间，至少 1,020,000 m ³被添加到河口，1,065,000 m ³的沙子被排放到岸面。源自 Shoalhaven 河的沙子保留在三个三级隔间的最北端，即七英里海滩，因为悬崖岬角和岩礁限制了来自南部的沿岸沉积物的贡献，并抑制了向北的泄漏。基于 41 年海岸线增生的预算余额与跨海岸运输和持续的 1–2 m ³岸面供应率一致/我的。尽管许多不确定因素限制了最终的沉积物收支，具有复杂的侵蚀或堆积模式以响应自然事件或工程干预，但这项初步研究表明使用地形地理空间分析得出沉积物路径和转移率的十年级估计的潜力变化，这可以为规划和管理行动提供基础。