Responses of Continental Aquatic Systems at the Global Scale: New Paradigms, New Methods

Abstract

Water figures prominently in the science of the Earth System and in the international agenda on global change. As a key component of the Earth’s climate and biogeochemistry the global hydrological cycle has received significant attention with respect to its role in land-atmosphere exchanges of water, energy and CO₂. This subject has, for this reason, constituted a major portion of this book. Water is also a key vehicle in the global mobilisation and transport of carbon, nutrients and suspended sediment, and it is these horizontal fluxes that Orient major interconnections between the Continental land mass and the world’s oceans. We shall focus in this chapter on the terrestrial water cycle and its role in the horizontal transport of land-derived materials which has been voiced as an Earth System and global change issue several times within the IGBP (Pernetta and Milliman 1995; Vörösmarty et al. 1997a). We refer here to “terrestrial aquatic Systems” for rivers, lakes, reservoirs, wetlands and groundwaters while using“continental aquatic Systems” to indude the former as well as deltas, coastal lagoons, estuaries, fjords, etc.