Proceedings of the Symposium on Dynamics and Management Of
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Regional Management of Mediterranean Abstract: Management of the fragile and greatly modified ecosystems in the Spanish Mediterranean Ecosystems in Spain1 climate is complex. Rainfall occurs in a few intensive storms on rough topography. Climax vegetation is sparse forest dominated by evergreen xerophilic species. The emphases of the National Jose A. Carrera, Estanislao de Simon, and Manuel Fisac2 Institute for Nature Conservation (ICONA) are forest hydrology restoration, restoration of forest potential, attainment of forest structure, and protection of natural spaces with singular ecological characteristics. This paper discusses the goals of management, evolution of forest management, management problems, scientific infor- mation in forest management and restoration, and national level studies on reforestation, hydrol- ogy, and desert control. Most of Spain has a typical Mediterranean among which the holly-oaks (Quercus ilex), kermes climate. Because of its geographic situation and oaks (Quercus faginea), and isolated pine trees topography, many different climate varieties are stand out. represented, from the arid in southeastern Spain to the Mediterranean high mountain in the Sierra The scarcity of tree species compatible with Nevada. This variety of climates gives rise to a our climate, and the differentiation between the series of ecosystems, normally much altered by existing ones, have caused numerous "endemismos." human activity, and very difficult to restore Professor Luis Ceballos considers that this is due because of their fragility and climatic character- to the isolation of Spain between the Pyrenean istics. Cordillera and the Mediterranean Sea. Among these species are the Spanish fir tree (Abies pinsapo) The European Mediterranean climate is charac- in the Penibetica Mountains. In North America, terized by a very dry summer. Rainfall normally north of the 36th parallel, more than 450 species takes place in a few days but is very intensive. of autochthonous forest trees can be cited, while Together with a rough topography, this causes in the south of Europe there are hardly more than torrential watercourses. This is an aspect which 70. From fossils, it is known that many species conditions the management and control of large now living far from the Mediterranean zone were areas of our country. present during the Tertiary in the European Merid- ian. This data should be useful for the restora- The vegetation climax is the sparse forest or tion of degraded ecosystems, in which selection is woodlot with evergreen xerophilic species, of difficult due to the scarcity of autochthonous which the holly-oak (Quercus ilex) is the most species. Thus we could try to restore some trees representative, occupying the greatest area. The lost by accident in the Mediterranean zones. On most characteristic coniferous species in this the other hand, the diversity of our Mediterranean region are Pinus halepensis, the Mediterranean climates allows us to try some species which were subtype of Pinus nigra, Pinus pinaster, and Pinus earlier represented in the habitat but later were sylvestris. replaced by other species of minor rank. Profes- sor Ceballos considers that there are three coni- In the temperate and dry zones, the holly-oak fers in a progressive stage to be borne in mind overstory leaves room for the wild olive tree for the restoration of Mediterranean ecosystems: (Olea europea), represented in the transition cypress (Cupressus sempervirens), cedar (Cedrus zones by the "coscoja" (Quercus coccifera). In atlantica), and spruce fir (Abies pinsapo). the driest zones, and where erosion has degraded the soil, the Mediterranean "garriga" appears on calcareous soils, representing the tropophyla GOALS OF MANAGEMENT vegetation and forming a clear and discontinuous bush. On siliceous soils the "maquis" appears, a Forest management is a dynamic concept as a closed underbush of rockrose (Cistus) with "len- consequence of social, economic, and political tiscos" (Pistacia) and strawberry trees (Arbutus) conditions. The human being has always tried to make full use of the resources available to him. While the resources were abundant and the popula- tion's necessities were met, there was no clear 1Presented at the Symposium on Dynamics and commitment to management. The forest was consid- Management of Mediterranean-type Ecosystems, June ered only as a timber producer and a supplier of 22-26, 1981, San Diego, California. fuel, which meant intense deforestation in Spain. When the resources became scarce and the needs for 2Dr. Engineers, ICONA (Instituto National para forest products increased, there was concern about la Conservacion de la Naturaleza), Madrid, Spain. the precarious situation of our forest, and a Gen. Tech. Rep. PSW-58. Berkeley, CA: Pacific Southwest Forest and Range 26 Experiment Station, Forest Service, U.S. Department of Agriculture; 1982. period of forest conservation began in the middle Almost half of the management work was con- of the last century, coinciding with the creation cluded during the decade 1951-61. of the Forest Corps. Among the intact or little degraded ecosystems Every ecological system has an optimum level of is the holly-oak forest of Quercus ilex, the most stable and permanent vegetation representing the representative for the Mediterranean zone. It is biological maximum permitted by environmental the most typical tree in Spain and there are conditions. In the Spanish forests the vegetation approximately 550,000 ha high forest, 850,000 ha climax is represented by more or less closed woodlot forest, and 856,000 ha of coppice forest. forests of coniferous trees in the high mountain During historic periods, this forest covered the zones and of hardwoods in the middle and low majority of our land area. Its perfect adaptation mountains, and only in the dry zones of the litto- makes it take advantage of all the Mediterranean ral and on the tops does the bush represent the climate characteristics, first of all keeping the climax. The resulting ecosystems are briefly soil moisture, thanks to the density of its crowns described according to land use; the limitations and the thickness of the organic horizon formed of this work do not allow us to particularize each under it. These permit it to vegetate perfectly one of the existing ecosystems and their precise during the long dry periods, having strong resis- relations. tance to drought, hot weather, and the dry air of the Mediterranean summer. It extends from sea The Spanish School of Management was born as an level to 2000 m elevation, where it can be found offshoot of the German School of Tharand, and its in the Sierra Nevada, although its optimum is focus was basically economic, addressing maximum between 200 and 1200 m. timber production. However, it was early adapted to the characteristics and problems of the Medi- In a more humid environment, the climatic terranean forests, first taking into consideration vegetation consists of gall oaks (Quercus faginea) other products, such as cork and resins, and from and cork-trees (Quercus suber). The first can be the beginning giving preponderance to soil protec- found in almost all the provinces in Spain. It is tion. Already in 1930 it was taking into consid- perfectly adapted to the humid Mediterranean soil eration such indirect benefits as esthetic, scien- and is a half-light tolerant species. It can tific, health, and recreational values. reclaim the habitat from where it was displaced and usually does at the expense of holly-oak, Thus, we reached the present consideration of which acts as a subclimax species in the humid the forest as providing for multiple use, and the Mediterranean soil. The second oak species can be concept that forest management should direct and found on siliceous soils in the southeast and guide it to the optimum indicated of its natural, northeast of the country. In the mountains, Pinus social, and economic functions, through convenient sylvestris is extensively represented, and occu- planning in time and space for its exploitation, pies this habitat from the Pyrenean Mountains to utilization, substructure, and improvement within the Sierra Nevada, where in Cerro del Trevenque it the limits imposed by the biological requirements. reaches its most meridional spontaneous form. This direction towards the optimum implies the The climax ecosystems of mountain peaks gener- following master lines of activity: ally form a dwarf bush of savins, integrated by Juniperus sabina humilis and Juniperus communis − Forest hydrologic restoration of watersheds. nana, accompanied by cushioned bush of brooms mixed with fescue grass, which is graminaceous − Forestation of areas with forest potential. grass with stiff leaves. − Attainment of a suitable structure of forest On sandy ground and littoral marshes, the stands. vegetation climax is integrated by Juniperus phoenicea, Retama monosperma, Lotus creticus, − Protection of natural spaces with singular Corema album, etc., adapted to resist the action ecological characteristics. of dominant winds, which are very common in these zones. As a result of past actions, there are at present nearly 2 million ha under management, the Of great ecological value is the interesting first dating from 1895, most of them softwood ecosystem in the National Protected Space of "El species (1,450,000 ha) mainly Pinus sylvestris and Sabinar," on the coast of Almeria in the south- P. pinaster (each 466,000 ha) P. larico and P. east of Spain. Its basic association of Juniperus halepensis (each 200,000 ha) P. uncinata (100,000 and Pistacea is sporadically joined by Tamarix, ha) and smaller surfaces with P. pinea, P. and composes, with its fauna, a sabulous bioceno- radiata, P. canariensis, and Abies pectinata. For sis, the only one on the Andalusian coast. It is hardwoods, there is a total area of 380,000 ha, a relic ecosystem, which once, in historic times, most of these being Fagus sylvatica and Quercus occupied all this coast. robur (200,000 ha). Eucalyptus (125,000 ha), Q. suber (50,000 ha), and small areas of other As an example of transformed ecosystems, which Quercus spp.