This book contains selected papers presented during the Symposium
“Sustainability of Dehesas, Montados and other Agrosilvopastoral
Systems”, held in Caceres, Spain, between September 21 and 24, 2003.
Agrosilvopastoral systems are widespread in the Mediterranean but are
also found in other areas of the world having similar climatic
conditions. In the southern and western part of the Iberian Peninsula
these land use systems have existed for many centuries, and are
commonly formed by open evergreen oak woodlands, covering
approximately 4 million hectares. These are areas referred to as the
montados and dehesas of Portugal and Spain, which traditionally are
exploited by multiple land use including livestock breeding, forestry
and cultivation. The importance of these areas rests on both
environmental as well as socio-economic values. They support an
outstanding diversity of wildlife, form unique landscapes, are the
source of high-quality food derived from animal production, sustain
rural population, and constitute an important basis for the growing
demand of rural leisure and tourism.
However, these areas have undergone rapid changes during the second
half of the 20th century, shifting from traditional farming systems
with very low external energy inputs to more simplified systems
causing decreasing diversity of land use and inadequate management
techniques. Land degradation is recognized as a significant problem in
many of the dehesas and montados, including the lack of tree
regeneration, which threatens the future of the woodlands as well as
soil erosion, soil degradation and increased runoff production.
A common feature is the coexistence of extensification and
intensification, causing different problems of degradation. For
example, headage payments led to an unchecked increase in animal
numbers, thus increasing the risk of soil and pasture degradation. On
the other hand, abandonment of livestock breeding produced vegetation
changes, leading to shrub encroachment, and an increased risk of
wildfires.
The book addresses both academics and practitioners interested in land
degradation and conservation of areas with agrosilvopastoral land use
in Mediterranean environments or other semi-arid areas with strong
seasonal contrasts. The editors hope that the volume will contribute
to the sustainable management of such landscapes.
The volume is organized in six sections. General aspects of
agrosilvopastoral systems in the Mediterranean basin are presented in
Section 1. The contribution by Papanastasis describes the variety of
land uses found in these systems, subject to recent changes and their
effect on vegetation degradation. The role of grazing is analyzed by
Enne et al. and Campos-Palacin presents reflections on the sustainable
economics of agroforestry systems. Two case studies on land use and
land cover changes in dehesas close this section.
Section two is dedicated to economic and social aspects of
agrosilvopastoral systems. In the third section studies on soil water
dynamics and soil degradation are presented, including a modeling
approach for analyzing stability in grazing systems. Chapter four
examines the linkages between livestock and vegetation, and chapter
five presents several studies on tree cover and forest use. The final
section is dedicated to the sustainability and management of
agrosilvopastoral systems, including studies from the Mediterranean
basin as well as from Mediterranean California.
Prolog
Chapter 1
Agrosilvopastoral Systems of the Mediterranean
Vasilios P. Papanastasis
Vegetation Degradation and Land Use Changes in Agrosilvopastoral Systems 1
Pablo Campos-Palacin
Towards a Sustainable Global Economics Approach for Mediterranean
Agroforestry Systems 13
Giuseppe Enne, Claudio Zucca, Anna Montoldi and Lorenzo Noè
The Role of Grazing in Agropastoral Systems in the Mediterranean Region
and their Environmental Sustainability 29
José M. Garcia del Barrio, Francisco Bolaños, Marta Ortega and Ramón
Elena-Rosselló
Dynamics of Land Use and Land Cover Change in Dehesa Landscapes
of the “REDPARES” Network between 1956 and 1998 47
Joaquin Francisco Lavado Contador, Susanne Schnabel and Rubén Trenado Ordóñez
Comparison of Recent Land Use and Land Cover Changes in Two
Dehesa Agrosilvopastoral Landuse Systems, SW Spain 55
Chapter 2
Social and Economic Aspects
Pablo Campos-Palacin and María Martinez-Jáuregui
Multiple Use of Pinus sylvestris and Quercus pyrenaica Forests in the
Spanish Central System 71
Yolanda Rodríguez-Luengo, Pablo Campos-Palacin and Paola Ovando-Pol
The Commercial Economics of a Public Dehesa in the Monfragüe Shire 85
Celeste Coelho, Teresa Carvalho, Abdellah Laouina, Miloud Chaker,
Rachida Naafa, Antonio Ferreira and Anne-Karine Boulet
Effects of Socio-Economic and Land Use Changes on Land Degradation:
Perception, Foreseen Impacts and Recommendations 97
Chapter 3
Hydrological and Degradational Processes
Elena Cubera, Maria Jesús Montero and Gerardo Moreno
Effect of Land Use on Soil Water Dynamics in Dehesas of Central-Westem
Spain 109
Maria Jesús Montero, José Jesús Obrador, Elena Cubera and Gerardo Moreno
The Role of Dehesa Land Use on Tree Water Status in
Central-Western Spain 125
Celeste Oliveira Alves Coelho, Antonio J.D. Ferreira, Abdallah Laouina,
Ali Hamza, Miloud Chaker, Rachida Naafa, Kamel Regaya,
Anne-Karine Boulet, Jan Jacob Keizer and Teresa M.M. Carvalho
Changes in Land Use and Land Management Practices Affecting Land
Degradation within Forest and Grazing Ecosystems in the Western
Mediterranean 137
José Rafael R. Marques da Silva and Alfredo Ferreira
Soil Texture Effects on Interrill Sediment Enrichment 155
Stergios Gakis
Accumulation of Organic Matter and Nutrients in the Surface Soil of a
Young Silvopastoral System in Greece 165
Jaime Martinez Valderrama and Javier Ibáñez Puerta
Foundations for a Dynamic Model to Analyze Stability in
Commercial Grazing Systems 173
Chapter 4
Livestock and Pastures
Nikos Beopoulos and George Vlahos
Exploitation of Pastures in a Sensitive Natural Environment:
The Case of Western Lesvos 183
Josefina Plaixats, Adriana Villareal, Jordi Bartolomé and Joaquim Espona
Productivity Characteristics of Grassland in a Dehesa System in
Catalonia, Spain 195
Jordi Bartolomé, Jesús Piedrafita and Josefina Plaixats
Preliminary Results on Diet Composition of the Alberes Semi-feral
Cattle Breed 203
Javier Montalvo, Paula Lorenzo and Adolfo Cano
Biomass Turnover as an Ecological Indicator of Vegetation Dynamics in
Agrosilvopastoral Systems of SW Galicia 209
Chapter 5
Trees and Forest Use
Marina Castro, José Castro and Antonio Gómez Sal
The Role of Black Oak Woodlands (Quercus pyrenaica Willd.)
in Small Ruminant Production in Northeast Portugal 221
Angel M. Felicísimo, Alicia Gómez and Jesús Muñoz
Potential Distribution of Forest Species in Dehesas of Extremadura
(Spain) 231
Ana Cristina Gonçalves, Susana Saraiva Dias, Alfredo Ferreira
and Nuno Almeida Ribeiro
Cork Oak (Quercus súber L.) Site Rating 247
Ana Cristina Gonçalves, Susana Saraiva Dias, Alfredo Ferreira and Nuno
Almeida Ribeiro
Landscape Diversity Patterns in Alentejo, Portugal 255
Maria José Leiva and Rocío Fernández-Aléz
Factors Limiting the Sexual Regeneration of Holm Oak (Quercus ilex
subsp. Ballota) in Dehesa Agroforestry Ecosystems of Sierra Morena
(Spain) 263
Nuno Almeida Ribeiro, Susana Saraiva Dias, Peter Surovy
Ana Cristina Gonçalves, Alfredo Ferreira and Angelo Carvalho Oliveira
The Importance of Crown Cover on the Sustainability of Cork Oak Stands:
A Simulation Approach 275
Peter Surovy, Nuno Almeida Ribeiro, Angelo Carvalho Oliveira and Lubomir Scheer
Automated Aerial Imagery Analysis System for Individual Tree Identification in Cork Oak Stands 287
Xavier Ubeda, Alfredo Ferreira and Maria Sala
The Nutritive Status of Quercus suber L.in the Province of Girona, Spain:
A Foliar Analysis 297
Chapter 6
Sustainability and Management of Agrosilvopastoral Systems
Lynn Huntsinger, Adriana Sulak, Lauren Gwin and Tobias Plieninger
Oak Woodland Ranchers in California and Spain Conservation and
Diversification 309
José Jesús Obrador Olán, Eustolia García López and Gerardo Moreno
Consequences of Dehesa Land Use on the Nutritional Status of
Vegetation in Central Western Spain 327
Juan Fernando Gallardo Lancho and Maria Isabel González Hernández
Sequestration of Carbon in Spanish Deciduous Oak Forests 341
Adriana Sulak, Lynn Huntsinger, Richard Standiford, Adina Merenlender
and Sally K. Fairfax
A Strategy for Oak Woodland Conservation: The Conservation Easement in
California 353
Rafael Blanco Sepúlveda
Land Evaluation for Extensive Grazing by Estimating Soil Vulnerability
to Degradation: A Case Study in a Goat Farm in Southern Spain 365
Monica Murillo, Susanne Schnabel and Francisco González
Effects of Different Pasture Improvement Techniques on Soil Erosion and
Herbaceous Vegetation in a Wooded Rangeland, South-West Spain 377
