Connectivity has become an important indicator of the sediment transfer potential through sediment sources to catchment sinks. Connectivity plays a vital role in investigating the rate of soil erosion caused by runoff and sediment output across the watershed landscape. However, there have been few quantitative studies on the spatial variations in sediment connectivity in the black soil region of Northeast China. Seven classic watersheds in the northeast black soil region were selected to discover spatial variations in sediment connectivity and their influencing factors. The connectivity index (IC) was used to study the spatial variation of sediment connectivity, and the weight of IC was calculated using the vegetation cover management factor (), which reflected the influence of human activities on the soil erosion process caused by cultivated land expansion and encroachment of forest grassland. The redundancy analysis method (RDA) was used to determine the main factors affecting the spatial variation of IC. The results showed that IC decreased from north (0.45) to south (0.12). The spatial variations of watersheds in sediment connectivity showed significant spatial heterogeneity. IC was correlated with topographic, climatic, and artificial management characteristics at 0.01 or 0.05 levels except soil structural index; RDA results showed that topography and human activities were the main factors affecting sediment connectivity. Topographic and climatic factors explained more sediment connectivity changes in the southern watersheds than in the northern watersheds, while the human activities factor explanation was the opposite of topographic factors. Human activities refer to changes in vegetation cover and soil structure and properties resulting from human logging and farming that affect sediment connectivity.

中文翻译：

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东北黑土区沉积物连通性空间变化特征及影响因素


连通性已成为沉积物从沉积物源到流域汇的转移潜力的重要指标。连通性在调查流域景观径流和沉积物输出引起的土壤侵蚀率方面发挥着至关重要的作用。然而，目前对东北黑土区沉积物连通性空间变化的定量研究还很少。选择东北黑土区7个经典流域，揭示沉积物连通性的空间变化及其影响因素。连通性指数（IC）用于研究沉积物连通性的空间变化，并利用植被覆盖管理因子（）计算IC的权重，反映人类活动对耕地扩张引起的水土流失过程的影响以及森林草地的侵占。采用冗余分析法（RDA）确定影响IC空间​​变异的主要因素。结果表明，IC从北（0.45）到南（0.12）逐渐减小。流域沉积物连通性的空间变化表现出显着的空间异质性。除土壤结构指数外，IC与地形、气候和人工管理特征在0.01或0.05水平上相关； RDA结果表明，地形和人类活动是影响沉积物连通性的主要因素。地形和气候因素对南部流域沉积物连通性变化的解释多于北部流域，而人类活动因素的解释则与地形因素相反。 人类活动是指人类伐木和耕作造成的植被覆盖、土壤结构和特性的变化，影响沉积物的连通性。