The impact of saltwater intrusion on coastal forests and farmland is typically understood as sea-level-driven inundation of a static terrestrial landscape, where ecosystems neither adapt to nor influence saltwater intrusion. Yet recent observations of tree mortality and reduced crop yields have inspired new process-based research into the hydrologic, geomorphic, biotic, and anthropogenic mechanisms involved. We review several negative feedbacks that help stabilize ecosystems in the early stages of salinity stress (e.g., reduced water use and resource competition in surviving trees, soil accretion, and farmland management). However, processes that reduce salinity are often accompanied by increases in hypoxia and other changes that may amplify saltwater intrusion and vegetation shifts after a threshold is exceeded (e.g., subsidence following tree root mortality). This conceptual framework helps explain observed rates of vegetation change that are less than predicted for a static landscape while recognizing the inevitability of large-scale change.

中文翻译：

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调节沿海景观盐碱化的反馈


咸水入侵对沿海森林和农田的影响通常被理解为海平面驱动的静态陆地景观的淹没，其中的生态系统既不适应也不影响咸水入侵。然而，最近对树木死亡率和作物产量下降的观察激发了对所涉及的水文、地貌、生物和人为机制进行新的基于过程的研究。我们回顾了几种有助于在盐胁迫早期阶段稳定生态系统的负面反馈（例如，减少幸存树木的用水量和资源竞争、土壤堆积和农田管理）。然而，降低盐度的过程通常伴随着缺氧的增加和其他变化，这些变化可能会在超过阈值后放大盐水入侵和植被移动（例如，树根死亡后的沉降）。该概念框架有助于解释观察到的植被变化率，这些变化率低于静态景观的预测值，同时认识到大规模变化的必然性。