En las zonas áridas, la acción combinada del cambio climático y el aumento de la presión humana están causando una degradación acelerada de los ecosistemas. En este contexto, es necesario investigar nuevas estrategias de restauración que nos permitan mejorar las acciones de restauración en estas zonas. Para ello, en esta tesis se exploró el uso de biocostras, comunidades de organismos que colonizan los primeros centímetros del suelo y que viven en estrecha asociación con las partículas del suelo, para la recuperación de suelos degradados en ecosistemas áridos. De entre todos sus componentes, se investigó el potencial uso restaurador de la inoculación con especies de cianobacterias formadoras de biocostras, pues son los organismos que más potencial presentan para restaurar zonas áridas debido a sus condiciones fisiológicas adaptadas a ambientes extremos y su facilidad para ser aisladas y cultivadas ex situ. En concreto, se evaluó la viabilidad de diferentes especies nativas de cianobacterias para promover el desarrollo de una nueva biocostra que mejore las condiciones de los suelos degradados de zonas áridas, así como estrategias para la reducción del estrés ambiental en condiciones de campo. Los resultados de esta tesis constituyen un avance significativo en el uso de esta tecnología para recuperar suelos afectados por la degradación en ecosistemas áridos.

This volume summarizes our current understanding of biological soil crusts (biocrusts), which are omnipresent in dryland regions. Since they cover the soil surface, they influence, or even control, all surface exchange processes. Being one of the oldest terrestrial communities, biocrusts comprise a high diversity of cyanobacteria, algae, lichens and bryophytes together with uncounted bacteria, and fungi. The authors show that biocrusts are an integral part of dryland ecosystems, stabilizing soils, influencing plant germination and growth, and playing a key role in carbon, nitrogen and water cycling. Initial attempts have been made to use biocrusts as models in ecological theory. On the other hand, biocrusts are endangered by local disruptions and global change, highlighting the need for enhanced recovery methods. This book offers a comprehensive overview of the fascinating field of biocrust research, making it indispensable not only for scientists in this area, but also for land managers, policy makers, and anyone interested in the environment.

Half a century ago, soil ...

In arid lands, where vegetation is sparse or absent, the open ground is not bare but generally covered by a community of small, highly specialized organisms. Cyanobacteria, algae, microfungi, lichens, and bryophytes aggregate soil particles to form a coherent skin - the biological soil crust. It stabilizes and protects the soil surface from erosion by wind and water, influences water runoff and infiltration, and contributes nitrogen and carbon to desert soils. Soil surface disturbance, such as heavy livestock grazing, human trampling or off-road vehicles, breaks up the fragile soil crust, thus compromising its stability, structure, and productivity. This book is the first synthesis of the biology of soil crusts and their importance as an ecosystem component. Composition and functioning of different soil-crust types are discussed, and case studies are used to show the impact of crusts on landscape hydrology, soil stability, nutrient cycles, and land management.

Nearly one-third of the land area on our planet is classified as arid or desert. Therefore, an understanding of the dynamics of such arid ecosystems is essential to managing those systems in a way that sustains human populations. This second edition of Ecology of Desert Systems provides a clear, extensive guide to the complex interactions involved in these areas. This book details the relationships between abiotic and biotic environments of desert ecosystems, demonstrating to readers how these interactions drive ecological processes. These include plant growth and animal reproductive success, the spatial and temporal distribution of vegetation and animals, and the influence of invasive species and anthropogenic climate change specific to arid systems. Drawing on the extensive experience of its expert authors, Ecology of Desert Systems is an essential guide to arid ecosystems for students looking for an overview of the field, researchers keen to learn how their work fits in to the overall picture, and those involved with environmental management of desert areas. - Highlights the complexity of global desert systems in a clear, concise way - Reviews the most current issues facing researchers in the field, including the spread of invasive species due to globalized trade, the impact of industrial mining, and climate change - Updated and extended to include information on invasive species management, industrial mining impacts, and the current and future role of climate change in desert systems

Soils have been called the most complex microbial ecosystems on Earth. A single gram of soil can harbor millions of microbial cells and thousands of species. However, certain soil environments, such as those experiencing dramatic change exposing new initial soils or that are limited in precipitation, limit the number of species able to survive in these systems. In this respect, these environments offer unparalleled opportunities to uncover the factors that control the development and maintenance of complex microbial ecosystems. This book collects chapters that discuss the abiotic factors that structure arid and initial soil communities as well as the diversity and structure of the biological communities in these soils from viruses to plants.