Chapters authored
Changes in Land Management of Iberian Rangelands and Grasslands in the Last 60 Years and their Effect on Vegetation
Rangelands and grasslands occupy now more than 3 million ha in the Iberian Peninsula representing one of the most valuable ecosystems. They are particularly interesting due to their great geographical spread and heterogeneity in land management. Significant changes have been undergone in the last 60 years affecting vegetation. The main goal in this study was to compile existing information about the changes in the Iberian rangelands and grasslands, their geographical distribution, typologies, main characteristics as well as past and recent land management based on a thorough bibliographical review and serious research. This has been subdivided into five large groups according to climate and human drivers: (1) Mediterranean rangelands and steppes, (2) oceanic grasslands, (3) mountainous meadows, (4) semi-arid steppes and (5) Portuguese rangelands and grasslands. Two milestones over the past 60 years were remarkable as main driving forces: rural exodus in the 1960s and 1970s and Spain and Portugal joining the European Union in 1986. They have provoked both processes of intensification and extensification at the same time on different scales. Many farms have been progressively fragmented using wire fences, and the numbers of livestock have been significantly increased. Land abandonment and grazing exclusion have provoked a large shrub encroachment of species such as Retama sphaerocarpa or Cistus ladanifer.
Part of the book: Vegetation
The Availability of Water in Chile: A Regional View from a Geographical Perspective
Chile is famous for being the longest country in the world from north to south. It means it ranges from polar to desert conditions, water being one of the main limiting factors. In fact, Chile stores a high amount of water (695 mm y−1), but people are not located in the regions where water is more abundant (e.g. in the south). This territorial imbalance is accompanied both by a global context of climate change in which water will be presumably scarcer and by the effects of the current economic activities that are progressively more demanding in water consumption. In this work, we have compared both the current and future availabilities of water for the different regions of Chile in order to provide relevant and useful information on the water balance for land planners. The Metropolitan and Valparaíso regions (Mediterranean climate) along Antofagasta, Atacama, and Tarapacá regions (desert climate) showed the lowest mean values of water availability from 1970 to 2000 (<125 m3 person y−1). In addition, both the optimistic and pessimistic projections for 2050 forecast a significant increase in the aridity of these two central regions, where the crucial axis between the two most important cities (Santiago and Valparaíso) is located.
Part of the book: Resources of Water