Ecohydrology of Water-Controlled Ecosystems

Abstract

Ecohydrology of Water-controlled Ecosystems addresses the connections between the hydrologic cycle and plant ecosystems, with special emphasis on arid and semi-arid climates. This important topic is treated by building suitable mathematical models of the physics involved and then applying them to study the ecosystem structure and its response to rainfall and climate forcing in different parts of the world, including savannas, grasslands and forests. It investigates the vegetation response to water stress (drought), the hydrologic control on cycles of soil nutrients, and the dynamics of plant competition for water. The book also offers insights into processes closely related to soil moisture dynamics, such as soil-atmosphere interaction and soil gas emissions. This book will appeal to advanced students and researchers from a large range of disciplines, including environmental science, hydrology, ecology, earth science, civil and environmental engineering, agriculture and atmospheric science.

Noise-induced stability in dryland plant ecosystems

“…To investigate the effect of the feedback between soil moisture and vegetation dynamics, we model the soil water balance for a shallow soil layer of thickness, Z, as (19) …”

Stochastic soil water balance under seasonal climates

“…Thus, x is simply a standardized version of relative soil moisture s, defined by x = (s − s w )/(s 1 − s w ). With the above assumptions, the effective soil moisture balance, vertically averaged over the rooting zone, is [17,22,25] …”

Background

“…Such processes provoke thermal changes on the Earth's surface by increasing the planetary albedo as SO 2 currently does or reinforcing the ▶ greenhouse effect as occurs with some N-bearing gases. Moreover, the manner in which the structure, composition, and substrate of extensive woodlands control the water and thermal balance, which is essential for hydrological cycles at regional and global scales, has been repeatedly described (Rodríguez-Iturbe and Porporato 2004). Interestingly, the great oxygenation event driven by microbial activity during the Late Archean-Early Proterozoic can be considered, on a greater scale, as a similar process of environmental control leading to the emergence of ▶ homeostasis as observed in the ecological succession of areas, which are initially devoid of living forms.…”