The Systems of Grassland Management in Spain
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Reprinted from: Managed Grasslonds, cd. by A. Breymeyer © Eisevier Scicnce Publishers B.V., Amslerdal11- Printed in The Nelherlands Chapter 3 THE SYSTEMS OF GRASSLAND MANAGEMENT IN SPAIN 1 PEDRO MONTSERRAT and FEDERICO FILLAT I !j: INTRODUCTlON data we use recompilations: Climatology (Instituto Nacional de Meteorologia, 1983), Agriculture Spain is a very old country, with diversilied (Ministerio de Agricultura, Pesca y Alimentación, landscape and rich history. The present features of 1980), History (Vicens Vives, 1954; Ubieto, 1970). its counties and lields 'are the result of a very long Knowledge of historical development and pre evolution, with Ínteractions of climate, animals sent-day diversilication make itpossible to predict and human cultures. how to utilize the existing ecological diversity of As a normal country of the temperate zone, the country in order to exploit the geographical, Spain was largely forested,. mainly with evergreen phytosociological and cultural possibilities. Spain oaks; also the mountains and the western side were is mountainous, with many poor soils well adapted covered by deciduous oaks, beech, pine and mixed to extensive husbandry. forests. Only at the top ofthe mountains and in the endorheic basins were there natural grasslands. The wild animals and natural lires extended the GENERAL ASPECTS grassland into forests and, latel', the farmers and shepherds produced a big expansion of open land. In a map taken from the work of Hernández The Iberian Peninsula is the biggest and the Pacheco (1932) (Fig.3.1), we have outlined the most mountainous region in southwestern Europe main features of the ''Three Spains": the siliceous and'is eharacterized by a continental c1imate and area on the west, the calcareous lands on the east, strong contrasts from Atlantic to Mediterranean and the c1ay areas making up the main river valleys or sub-desertic environments. Cultural infiuences of Spain (Duero, Ebro, Guadalquivir), with the from the Near East arrived quickly by maritime limestone mountain ranges in the east (the Le routes and more slowly through North Africa or vante), the Cordillera Iberica and the Cantabrian Europe. Thus, diversilied influences in space and Pyrenean Mountains. The evaporites' of La time are at the origin of the present mosaic in Mancha and those of the Duero and Ebro Rivers grasslands, flocks and human uses. are also shown in the map. In this paper we intend to introduce the main The dotted areas indicate mountains and moun grazing systems of Spain now; they are c1assilied tain chains over 1000 m above sea-Ievel; on the and named by Spanish words taken from names of islands only the Sierra de Mallorca rises above plants (zulla), landscapes (boo/al', dehesa, borreguil, 1000 m, while the Sierras of the other islands majada), types of herds (manchega, segul'eña) or hardly reach a height of 300 to 400 m. cultural traditions (minifundus, pasiego, borda, The complex orography, with an average height Mesta). Of course, geographic or ecological de of c. 800 m, gives rise to a great variety of scriptions are used in each case. Basic )nformation is drawn mainly from our own experience; the specialized literature has been lEvaporites: Rocks formed by the evaporation of brackish cited and listed synthetically, and for the statistical water. 37 38 PEDRO MONTSERRAT and FEDERICO FILLAT OYER 1000 M SI LI CEOUS LAND CALCAREOUS LAND CLAYEY LAIID 1°0°0°01 EVAPORITES Fig. 3.L Thc lithology of Spain andBalcaric Isles (based on HcrnándezPachcco, 1932). environments ",ith valleys and eroded slopes, and Cantábrica with isolated points in central and to lithosoils in which geological features predomi southern Spain (Sierras de Gredos, Guadarrama nate. The rainfall is moderate, while vegetation is and Grazalema, and the Serrania de Ronda). sparse, and dense woodland is rareo Soils are (b) Humid with dry periods and 800 to 1400 mm inappropriate for sustained agricultural exploita of precipitation in mountains of northern and tion, and advantage can be taken ofrough pasture central Spain, with isolated areas in the Sierra de land only by a specialized and diversified animal Guadalupe, Montes de Toledo, Sierra Aracena, hnsbandry. [See also Aguilar (1961) and Selec Sierra Madrona, La Sagra, Sierra -Nevada, Sierra ciones (1962) with maps on these topics.] Mariola in Alicante and the Sierra de Montseny and Guillerias near Barcelona. General charaeteristies of bioelimate (c) Dry clima tes in the Duero and Ebro Valleys, La Alcarria and the valleys ofthe Jalón and Jiloca; A description of the bioclimatic conditions of the drought is extreme in the southeastern sub Spain is based on 30 years' measurements desertic climate of the Almeria Region. (1931-1960) by the Servicio Meteorológico Na Temperatures are related to altitude and lati cional. In the plnviometric map (Fig. 3.2A) it is tude. In Fig. 3.2B we have shown the general possible to see the main ranges of rainfall c1imate; meteorological features with the distribution of the (a) Very humid in Galicia and the Cordillera minimum temperatures of a typical anticycIone THE SYSTEMS üF GRASSLAND MANAGEMENT IN SPAIN 39 - .(.,. (A) • [2J > 2000 mm 0400-600 mm ·· 0300-400 mm O.-.'::'. ] 500-2000 mm r:cl 1000-1500 mm 0200-300 mm ~ ~ ~ 800-1000 mm 1:.;:·.:·1 <ZOO mm ".-.;¡ ~ 600-800 mm (E) ~ COLD AND DRY WINDS --- HOT AND TOO DRY WINDS (_~~~ THERMAL INVERSION 7 3, -2 MINIMUM TEMPERATU RES IN oC Fig. 3.2. Pluviometry, lemperaturcs and winds in Spain. A. AllIlUUl prccipitation (Servicio Meteorológico NaciOllal, 1965). B. Winds <'lud tcmpcratures. Minimum tempcratures on 4 Februury 1983 (from Servicio Meteorológico Nacional, 1972 and Instituto Nacional de Meteorología, 1983). Small squares are lhe main tO\VIlS. 40 PEDRO MONTSERRAT and FEDERICO FILLAT day' when the areas of important thermal inver The dotted areas on the map indicate the c10sed sion are localized in the Duero and Ebro Valleys interior valleys of the Peninsula where Iittle rain and in La Mancha. In areas c10se to the ocean falls, and it is irregularly dispersed tending to fall in (Galicia and Cantabrian coasts), the high atmo the hotter months as a result of convectional spheric humidity tempers extreme changes of storms. In these valleys there is a predominance of temperatllre, so the summers are reasonably coal, spring rains ("sprin'g-autumn-winter-summer"). favouring the growth ofmeadow without necessity Only in a few places such as the basins of the Jiloca of irrigation. In thc northeast, especially around and Alfambra (Teruel), La Cerdaña, the eastem Gerona, humidity from the Mediterranean Sea Pirinéos and Cadí, thcrc are frequent summer acts as a thcrmal regulator preventing extreme storms and this season is the rainiest ("summer desiccation. In the south and the Balearic Islands, spring-autumn-winter"). summer droughts are more extreme, due to the The areas which have been left blank are thosc excessive 1085 of llloisture caused by.long hours of whel'e c1imate is very changeable, oscillating strong sunshine heating the soi!. Andalucia is between the types aIready mentioned. under a joint influence of the Atlantic and the Logically, the regions with autumn and winter Mediterranean Sea with a maritime climate in the rains are those affected by the above-mentioned Strait of Gibraltar, cool and wet except at the maritime air-masses during the colder months and height of summer. where, therefore, the humidity is acting as a Wind plays an important part in mountain thennic regulator. The summers are usually dry areas, such as the leeward foehn typical ofthe great and, since vegetation is scarce, this general charac mountain ranges. Moist maritime air is drawn up teristic of Spain has contributed to the traditional over the crest and mists are frequen!. The importance of sheep, which must be moved to the descending currents of air are hot and dry. We weUer and cooler mountain areas. The autumn have endeavoured to show (Fig. 3.2B) those winds and spring rains characteristic of the Mediterra that are best known and intense in action such as nean c1imate facilitate the growth of trees such as the aptly-named Tramontana (the Mistral of the evergreen oak and the pine, especially Pin"s Ampurdán) the Cierzo and MeS/l'a/ of the Ebro ha/epensis. As one moves further inland the Valley and Tarragona, and the Abrego, a hot dry weather becomes variable with sudden changes of wind which blows down from the Meseta towards temperature, and the vegetation becomes steppe the Cantábrico. The Regañon blows from. Galicia like, dry, with scrubbier grazings and very rough towards the Duero Valley. grasses. Finally, to give an idea of the seasonal fluctua The c1imatological studies of Spain are numer tions of rainfall in different parts of Spain we have ous and we select only some papers like: Filia t drawn a map (Fig. 3.3) showing the predominance (1983) for seasonality ofrains, and a simplifica tion of rainfall in any given season. The typical winter by leona and González Rebollar (1974). Maps are rains of the Atlantic zone do not penetrate very far based also on those of the Servicio Meteorológico inland due to the action of the Iberian anticyclone; Nacional (1965, 1972) and the Instituto Nacional located in the centre ofthe Peninsula in this season. de Meteorologia (1983). Regional studies include However, these heavy winter and autumn rains do those on Galicia by Diaz Fierros (1971); on prevail in some valleys, Iike that of the Guadalqui Cataluña, by Febrer(l930); on Aragón by Liso vir and especial1y the Tajo. and Ascaso (1969); and central Spain by Sánchez Moving inland from the Atlantic-Cantabrian Egea (1975). Region and because of the altitude it can be seen that the maximum amount of rain falls in winter and spring ("winter-spring-autumn-summer" on the map). In the east, the rains are characterized by MediterranerlO infiucnce and the autumn is the typical season (Balearic Islands, Valencia); in the 1Priday 4 February 1983, mininlllm temperatures.