Agricultural headwaters are positioned at the interface between terrestrial and aquatic ecosystems and, therefore, at the margins of scientific disciplines. They are deemed devoid of biodiversity and too polluted by ecologists, overlooked by hydrologists, and are perceived as a nuisance by landowners and water authorities. While agricultural streams are widespread and represent a major habitat in terms of stream length, they remain understudied and thereby undervalued. Agricultural headwater streams are significantly modified and polluted but at the same time are the critical linkages among land, air, and water ecosystems. They exhibit the largest variation in streamflow, water quality, and greenhouse gas emission with cascading effects on the entire stream networks, yet they are underrepresented in monitoring, remediation, and restoration. Therefore, we call for more intense efforts to characterize and understand the inherent variability and sensitivity of these ecosystems to global change drivers through scientific and regulatory monitoring and to improve their ecosystem conditions and functions through purposeful and evidence-based remediation.

中文翻译：

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认识到农业源头是重要的生态系统

农业源头位于陆地和水生生态系统的交界处，因此处于科学学科的边缘。生态学家认为它们缺乏生物多样性，污染严重，水文学家忽视它们，土地所有者和水务部门认为它们是一种滋扰。虽然农业溪流分布广泛，并且就溪流长度而言代表了主要栖息地，但它们仍然未被充分研究，因此被低估。农业源头河流受到显着改变和污染，但同时也是土地、空气和水生态系统之间的关键联系。它们在水流、水质和温室气体排放方面表现出最大的变化，对整个河流网络产生连锁效应，但它们在监测、修复和恢复方面的代表性不足。因此，我们呼吁加大力度，通过科学和监管监测来描述和了解这些生态系统对全球变化驱动因素的固有变异性和敏感性，并通过有目的和基于证据的修复来改善其生态系统条件和功能。